Thorne Ferrasorb Review
Advanced Iron Complex is presented on this Thorne page as a capsule that supplies iron, essential B vitamins and vitamin C for comprehensive nutritional support for iron-deficiency anemia. The page states that the product provides iron in chelated form for optimal absorption, with vitamin C included to enhance iron's absorption, plus the active forms of folate and vitamins B6 and B12. Each capsule provides 36 mg of elemental iron as Ferrochel chelate. The page explains that iron is essential to the formation and function of healthy red blood cells, and that an adequate amount of iron in the diet is required for blood cells to efficiently transport oxygen throughout the body. It cites the U.S. Centers for Disease Control, noting that up to 16 percent of individuals in certain populations are deficient in iron. Listed features include reduced GI side effects such as nausea and constipation, and active forms of vitamins B12, B6 and folate with vitamin C for an enhanced approach to red blood cell health. The page lists who may benefit, including individuals looking for nutritional support for anemia, women of menstruating age, individuals who follow a vegan or vegetarian diet, older individuals who tend to have less stomach acid, individuals who have undergone gastric bypass surgery, those with intestinal conditions that affect nutrient absorption, and individuals with an autoimmune disorder. Signs of iron deficiency named on the page include fatigue or weakness, shortness of breath, pale skin, cold hands and feet, feeling lightheaded or dizzy, changes in menstrual cycles and decreased athletic performance. The page notes that iron is difficult for the body to absorb and that conventional forms such as ferrous sulfate can cause gastrointestinal side effects including nausea, vomiting, constipation, diarrhea and dark-colored stools. Thorne states that this product contains iron reacted with glycine to enhance absorption and help decrease those typical side effects. The page also explains the reason for the B vitamins: a deficiency in them can lead to adverse issues with red blood cell formation, and signs named include fatigue or muscle weakness, decreased mood quality, sores in the mouth or on the tongue, problems with memory or cognition, and a feeling of being on pins and needles. The product is described as combining the active forms of vitamin B6 as pyridoxal 5'-phosphate, vitamin B12 as methylcobalamin and folate as L-5-methyltetrahydrofolate, along with vitamin C and a well-absorbed form of iron. Thorne describes the formula as made with the scientific rigor the brand is known for, with ingredients selected, clinically studied and tested through multiple rounds of quality control. The page states the product has been third-party tested and certified to verify that what is in the package matches the label and that it contains no unsafe levels of contaminants such as heavy metals, pesticides and microorganisms. The warnings section adds that the product is contraindicated in anyone with a history of hypersensitivity to its ingredients, that pregnant people should consult a health-care practitioner before use, and that 5-MTHF is not recommended concurrent with a med cancer therapy. It also warns that accidental iron overdose is a leading cause of fatal poisoning in children under six and that the product should be kept out of reach of children.
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Study, Trial or Testing Result Summary
Members Only132 human studies · 62 improved
34 of these 132 human studies gave the ingredient by drip or injection, not by mouth.
Iron is the main ingredient here, at a full dose of three capsules a day. Iron reduces tiredness mainly in people who are low in iron. A review of 18 trials in iron-deficient adults found less fatigue, but no better measured fitness [1]. Another review found that iron reduced fatigue in people without anemia, but the benefit disappeared when people with normal iron were included [2]. In 198 menstruating women with low iron stores, 80 milligrams daily for 12 weeks reduced fatigue more than placebo [3]. An iron infusion reduced fatigue in 65.3% of tired, iron-deficient women versus 52.7% on placebo [4]. Vitamin B6 reaches a full dose at three capsules a day, but large trials of blends containing it found no energy benefit [5][6]. Vitamin C here is below the studied dose. It helped mainly people whose vitamin C was low [7]. Vitamin B12 did not boost energy in people who were not deficient [8][9]. Adding folic acid to iron did not change fatigue in women with anemia after childbirth [10]. Expect benefit mostly if you are low in iron. Animal and cell studies are never counted.
See all 132 studies →Hide the studies
- Across 16 trials with 6276 people, B12 with or without folic acid and B6 did not improve thinking or depression, and only one trial looked at fatigue so it could not be analyzed.Effects of Vitamin B12 Supplementation on Cognitive Function, Depressive Symptoms, and Fatigue: A Systematic Review, Met…
- Across 33 trials of 4558 women with anaemia after childbirth, intravenous iron probably reduced fatigue slightly within 8 to 28 days compared with oral iron, though most evidence was low or very low certainty.Treatment for women with postpartum iron deficiency anaemia.
- In 20 trials of 4196 women with anaemia after childbirth, intravenous iron reduced fatigue more than oral iron, and also raised haemoglobin and ferritin, with low to moderate quality evidence.Intravenous iron versus blood transfusion for postpartum anemia: a systematic review and meta-analysis.
- In 18 studies of 1408 children, teens and menstruating adults without anaemia, iron supplementation reduced fatigue and improved anxiety, well-being and memory in placebo-controlled trials, but the effects were absent when people without iron deficiency were included.Psychiatric and cognitive outcomes of iron supplementation in non-anemic children, adolescents, and menstruating adults:…
- In 16 studies of 616 people with multiple sclerosis and 655 healthy people, folate and B12 blood levels did not differ, suggesting they are not drivers of worse physical function; this was not a supplement trial.The Relationship of Cobalamin and/or Folate to the Patient-Centred Outcomes in Multiple Sclerosis: A Systematic Review a…
- In 18 trials of 1170 iron-deficient adults without anaemia, iron reduced self-reported fatigue but did not improve measured physical capacity such as oxygen uptake.Efficacy of iron supplementation on fatigue and physical capacity in non-anaemic iron-deficient adults: a systematic rev…
- In 11 trials of 1074 adults with iron deficiency but no anaemia, intravenous iron slightly raised haemoglobin, but the evidence for fatigue and oxygen uptake was very low quality and too uncertain to show benefit.Intravenous iron therapy for non-anaemic, iron-deficient adults.
- In two placebo-controlled trials of 404 adults with Charcot-Marie-Tooth disease type 1A, ascorbic acid at two doses over 12 to 24 months had little meaningful effect on fatigue.Interventions for fatigue in peripheral neuropathy.
- In four placebo-controlled trials of people with iron deficiency anaemia, intravenous ferumoxytol improved fatigue scores and haemoglobin without raising adverse events.The Efficacy of Ferumoxytol for Iron Deficiency Anemia: A Meta-Analysis of Randomized Controlled Trials.
- Across nine studies of 720 people, three of four controlled trials found intravenous vitamin C lowered fatigue scores more than control, and four of five uncontrolled studies saw fatigue fall.Feasibility of Vitamin C in the Treatment of Post Viral Fatigue with Focus on Long COVID, Based on a Systematic Review o…
- In a review of 13 small trials with 85 people with McArdle disease, vitamin B6 gave no benefit for exercise performance.Pharmacological and nutritional treatment for McArdle disease (Glycogen Storage Disease type V).
- A review of 37 studies in cancer patients found intravenous vitamin C may ease fatigue and other symptoms, but the evidence is preliminary and mostly uncontrolled.Intravenous Vitamin C and Cancer: A Systematic Review.
- A review of supplements for football players said vitamin C may improve performance by lowering oxidative stress, but gave no numbers and called for more research.The efficacy of dietary supplements on health status and performance of football players: a systematic review.
- In a review of four diet trials in people with multiple sclerosis lasting 3 to 12 months, two diets supplying enough folate and magnesium reported improved fatigue, but firm conclusions were not possible.Is there an effect of dietary intake on MS-related fatigue? - A systematic literature review.
- In a review of 24 studies of supplements in wrestlers, iron supplementation improved recovery and may improve exercise performance, though effects were often small and results mixed across supplements.Evidence-Based Supplementation Strategies for Wrestlers: A Systematic Review.
- In 8112 healthy French adults, a daily antioxidant capsule containing 120 mg vitamin C for about 6 years did not change quality of life scores, including vitality, compared with placebo.Long-term antioxidant supplementation has no effect on health-related quality of life: the randomized, double-blind, pla…
- In 2501 heart disease or stroke survivors given low-dose B vitamins including 3 mg B6 for about 3 years, quality of life was not improved, and activity limits due to emotional problems were slightly worse.B vitamin and/or n-3 fatty acid supplementation and health-related quality of life: ancillary findings from the SU.FOL.O…
- In 812 adults with iron deficiency anaemia who could not use oral iron, intravenous ferumoxytol over 5 weeks improved fatigue scores more than placebo, and 81.1% reached the haemoglobin target versus 5.5% on placebo.Efficacy and safety of IV ferumoxytol for adults with iron deficiency anemia previously unresponsive to or unable to tol…
- In 405 non-anemic blood donors with low iron stores, a single 800 mg iron infusion raised ferritin and hemoglobin but did not change fatigue scores compared with placebo at 6 to 8 weeks.The effects of intravenous iron supplementation on fatigue and general health in non-anemic blood donors with iron defic…
- In 399 anemic patients after a long intensive care stay, hepcidin-guided intravenous iron (1 g) did not shorten later hospital stay and the abstract reports no fatigue result, though 90-day deaths were lower (8% vs 16.6%).Impact of treating iron deficiency, diagnosed according to hepcidin quantification, on outcomes after a prolonged ICU st…
- In an open-label randomized trial of 338 adults with iron deficiency anemia, high-dose intravenous iron raised hemoglobin faster than oral iron and improved fatigue scores more by 4 weeks, with similar side effect rates.[Comparison of the efficacy and safety between high-dose intravenous iron and oral iron in treating iron deficiency anem…
- In 311 people receiving a med agonist therapy, a daily fruit smoothie for 16 weeks did not change fatigue, fitness, or folate levels compared with standard treatment alone.Read the study on PubMed (40877839) →
- In 304 iron-deficient heart failure patients, intravenous iron for 52 weeks improved walking distance by 33 m at 24 weeks and improved fatigue score and quality of life compared with placebo.Beneficial effects of long-term intravenous iron therapy with ferric carboxymaltose in patients with symptomatic heart f…
- In 290 fatigued, iron-deficient women, a single 1000 mg iron infusion reduced fatigue in 65.3% versus 52.7% with placebo at 8 weeks, and improved mental quality of life and cognitive function.Evaluation of a single dose of ferric carboxymaltose in fatigued, iron-deficient women--PREFER a randomized, placebo-con…
- In 275 adults with early COVID-19 given a 10-day combination that included vitamin C, less fatigue at day 14 was seen only when famotidine was added, not with the vitamin C combination alone.Read the study on PubMed (41693032) →
- In 271 adults with Charcot-Marie-Tooth disease type 1A, 1.5 g of ascorbic acid daily for 2 years did not differ from placebo on neuropathy or on secondary outcomes including fatigue.Ascorbic acid in Charcot-Marie-Tooth disease type 1A (CMT-TRIAAL and CMT-TRAUK): a double-blind randomised trial.
- In 215 working men aged 30 to 55, a high-dose B vitamin, vitamin C and mineral supplement for 33 days improved vigour, stress and mental health ratings and made them feel less mentally tired than placebo.Effects of high-dose B vitamin complex with vitamin C and minerals on subjective mood and performance in healthy males.
- In 202 hemodialysis patients, a multinutrient supplement containing vitamin C for 12 weeks did not reduce fatigue compared with placebo, though some heart rate variability measures improved.Effects of nutritional supplementation on fatigue, and autonomic and immune dysfunction in patients with end-stage renal…
- In 198 nonanemic menstruating women with low ferritin and fatigue, 80 milligrams of elemental iron daily for 12 weeks reduced fatigue more than placebo, though quality of life did not change.Effect of iron supplementation on fatigue in nonanemic menstruating women with low ferritin: a randomized controlled tri…
- In 176 iron-deficient blood donors, intravenous or oral iron over 8 to 12 weeks significantly reduced fatigue and improved sleep, with no difference between the two forms.The Effect of Parenteral or Oral Iron Supplementation on Fatigue, Sleep, Quality of Life and Restless Legs Syndrome in I…
- In 171 young adults, two extra daily servings of fresh fruit and vegetables for 14 days improved vitality and motivation, but blood vitamin C did not explain these benefits.Let them eat fruit! The effect of fruit and vegetable consumption on psychological well-being in young adults: A randomi…
- In 171 adults with mild insomnia, a blend including vitamin B6 for 2 weeks did not differ from placebo on sleep or physical fatigue, as both groups improved similarly.Exploring the Effect of Lactium™ and Zizyphus Complex on Sleep Quality: A Double-Blind, Randomized Placebo-Controlled Tr…
- In 167 young adults with low vitamin C, a 250 mg vitamin C tablet daily for 4 weeks improved well-being after two weeks, and also mood and fatigue in those with consistently low vitamin C, while placebo showed no change; kiwifruit gave somewhat stronger effects.KiwiC for Vitality: Results of a Randomized Placebo-Controlled Trial Testing the Effects of Kiwifruit or Vitamin C Table…
- In 162 adults on a weight loss meal replacement program, folate levels improved in both groups, and energy and fatigue improved slightly more with daily calorie restriction alone than with added alternate day fasting; folate was not tested alone.Randomized Trial of a High Protein, Partial Meal Replacement Program with or without Alternate Day Fasting: Similar Effe…
- In 160 heart bypass surgery patients, vitamin C plus omega-3 fatty acids given from the day before surgery through the first 5 days after reduced post-operative fatigue more than placebo.The combined effect of vitamin C and omega-3 polyunsaturated fatty acids on fatigue following coronary artery bypass gra…
- In a double-blind placebo-controlled trial of 144 non-anemic women with unexplained fatigue, 80 mg daily of oral iron for 4 weeks reduced fatigue more than placebo, with the benefit seen mainly in women with low or borderline ferritin.Iron supplementation for unexplained fatigue in non-anaemic women: double blind randomised placebo controlled trial.
- In 141 healthy office workers, a single 10 gram intravenous vitamin C dose lowered fatigue scores for up to one day compared with saline placebo, especially in those with low starting vitamin C, and also lowered oxidative stress.Intravenous vitamin C administration reduces fatigue in office workers: a double-blind randomized controlled trial.
- In 112 women with anemia after childbirth, adding 1 mg a day of folic acid to iron for 4 weeks did not change fatigue scores, hemoglobin or health status compared with iron alone.A randomized controlled trial examining the addition of folic acid to iron supplementation in the treatment of postpartu…
- In 110 premenopausal women with iron-deficiency anemia from fibroids, both groups took 325 mg iron three times daily for 12 weeks, and adding a goserelin injection raised blood hemoglobin more than a sham injection did; the abstract does not test iron alone against no iron and reports no energy or fatigue result.Goserelin acetate 10.8 mg plus iron versus iron monotherapy prior to surgery in premenopausal women with iron-deficiency…
- In 100 pregnant women with iron deficiency anemia over 12 weeks, intravenous ferric carboxymaltose gave greater fatigue improvement than iron sucrose and needed fewer visits.Comparison of ferric Carboxymaltose and iron sucrose complex for treatment of iron deficiency anemia in pregnancy- rando…
- In a 3-month double-blind trial of 99 people with severe kidney failure taking 250 mg vitamin C three times weekly, symptoms including fatigue were similar to placebo, and nausea trended worse with vitamin C.Vitamin C supplementation in kidney failure: effect on uraemic symptoms.
- In 97 people with inflammatory bowel disease and iron deficiency anemia, fatigue scores improved over 5 weeks after intravenous iron with both products, but improvement was slower and smaller with ferric carboxymaltose.Hypophosphataemia following ferric derisomaltose and ferric carboxymaltose in patients with iron deficiency anaemia due …
- In 97 people with inflammatory bowel disease and iron deficiency anemia, intravenous iron over about 10 weeks improved vitality scores, a measure of energy, with larger gains after ferric derisomaltose than ferric carboxymaltose.Hypophosphatemia attenuates improvements in vitality after intravenous iron treatment in patients with inflammatory bowe…
- In 90 premenopausal women with fatigue and low ferritin, one 800 mg intravenous iron dose cut fatigue more than placebo only in women with ferritin of 15 or lower, where 82% of iron-treated women reported improvement; the overall difference was not significant.Intravenous iron for the treatment of fatigue in nonanemic, premenopausal women with low serum ferritin concentration.
- In 85 female blood donors, one 1000 mg intravenous iron isomaltoside dose raised hemoglobin more than placebo, but fatigue differences were only numerical and the trial was not powered for symptoms.Intravenous iron isomaltoside improves hemoglobin concentration and iron stores in female iron-deficient blood donors: a…
- In 80 people with advanced chronic kidney disease followed for 6 months, adding folic acid (alone or with pentoxifylline) to usual care reduced fatigue scores and improved kidney blood tests compared with usual care alone.The potential adding therapeutic effect of pentoxifylline and/or folic acid for chronic kidney disease patients: randomi…
- In 65 people with chronic fatigue syndrome, a daily combination with 1.05 mg B6, beta-glucan, vitamin D3 and zinc for 36 weeks improved cognitive fatigue compared with their own baseline.Yeast Beta-Glucan Supplementation with Multivitamins Attenuates Cognitive Impairments in Individuals with Myalgic Enceph…
- In 63 women with premenstrual symptoms (32 completed), 50 mg of vitamin B6 daily for 3 months in a crossover design improved emotional symptoms including depression, irritability and tiredness compared with placebo.Pyridoxine (vitamin B6) and the premenstrual syndrome: a randomized crossover trial.
- In 58 healthy adults with mild prolonged tiredness, a supplement combining pomegranate extract with B vitamins and vitamin C reduced fatigue scores over 8 weeks compared with placebo, though vitamin C was not tested alone and biochemical markers did not change.Combination of Chemically Characterized Pomegranate Extract and Hydrophilic Vitamins against Prolonged Fatigue: A Monoce…
- In 54 cancer patients with hand-foot skin reactions from chemotherapy, topical pyridoxine for 6 weeks did not improve the skin reaction grade, but patients reported lower fatigue, better physical function and better quality of life than the placebo group.A pilot randomized double-blind, placebo-controlled study on the effects of the topical application of pyridoxine on pal…
- In 53 female athletes with low iron stores, 20 mg iron plus a probiotic raised ferritin more than iron alone but not significantly, and increased vigor at 12 weeks, with no clear effect on physical performance.The Effect of Lactobacillus plantarum 299v on Iron Status and Physical Performance in Female Iron-Deficient Athletes: A …
- In healthy young adults with low vitamin C levels, 500 mg twice a day for 4 weeks improved attention and work absorption compared with placebo, with a trend toward less fatigue.Vitamin C supplementation promotes mental vitality in healthy young adults: results from a cross-sectional analysis and …
- In a 28-day placebo-controlled trial of 46 adults with long COVID, twice-daily liposomal vitamin C (500 mg) with l-arginine reduced persistent fatigue (2 of 23 still fatigued vs 21 of 23 on placebo) and improved walking distance and handgrip strength.Effects of l-Arginine Plus Vitamin C Supplementation on Physical Performance, Endothelial Function, and Persistent Fatig…
- In 41 trained cyclists, 4 weeks of a combination supplement including 2.5 mcg B12 did not improve aerobic or anaerobic performance or fatigue measures compared with placebo, though blood lactate was lower after hard exercise.l-Carnitine and Alpha-Lipoic Acid Fail to Improve Anaerobic and Aerobic Performance in Trained Cyclists Despite a Reduct…
- In 40 young adults with low vitamin C, 1000 mg daily for 4 weeks improved mental vitality and reduced inflammation compared with placebo, with gut bacteria changes linked to the gains.Gut microbiota links vitamin C supplementation to enhanced mental vitality in healthy young adults with suboptimal vitam…
- In 36 volunteers, 1 g of vitamin C daily for 30 days improved maximal oxygen uptake and lowered oxidative stress only in those with the lowest vitamin C levels, and it did not reduce fatigue index.Antioxidant supplementation, redox deficiencies and exercise performance: A falsification design.
- In 33 soldiers during a 12-day tropical training exercise, folate status declined in all groups and those eating combat rations reported more fatigue than those eating fresh food; folate was not given as a separate supplement.The physiological and psychological effects of combat ration feeding during a 12-day training exercise in the tropics.
- In 30 young women with premenstrual syndrome, both groups took vitamin B6 and calcium for 3 months; the group that also did treadmill exercise improved fatigue and other symptoms, so the effect is from exercise rather than vitamin B6.Effect of aerobic exercise on premenstrual symptoms, haematological and hormonal parameters in young women.
- In 30 women with gynecological disease and anemia before surgery, 100 mg daily iron for at least 10 days raised hemoglobin but did not significantly reduce fatigue; adding Ninjin'yoeito reduced fatigue.Safety and efficacy of Ninjin'yoeito along with iron supplementation therapy for preoperative anemia, fatigue, and anxie…
- In 28 men with marginal vitamin C status, 1000 mg daily for 8 weeks produced a physical activity rise that was not statistically significant compared with placebo, though cold episodes were fewer.Vitamin C supplementation slightly improves physical activity levels and reduces cold incidence in men with marginal vit…
- In 26 overweight middle-aged women doing aerobic training for 3 months, drinking 500 mL of orange juice daily was linked with lower blood lactate, suggesting less muscle fatigue than training alone.Orange juice improved lipid profile and blood lactate of overweight middle-aged women subjected to aerobic training.
- Eating two SunGold kiwifruit daily for 4 weeks improved mood disturbance, wellbeing and vitality compared with usual diet in 26 adults with mild to moderate mood disturbance.SunGold Kiwifruit and Psychological Health (GoKiPH): A Randomised Controlled Crossover Trial.
- In 26 recreationally active women with iron deficiency but no anemia, one intravenous iron treatment compared with placebo improved fatigue scores at 4 weeks.Effect of intravenous iron therapy on exercise performance, fatigue scores and mood states in iron-deficient recreationa…
- In 25 healthy young adults, a single dose of a pre-workout drink containing 500 mg vitamin C along with other ingredients raised self-rated energy and vigour compared with placebo, though adding synephrine gave no extra benefit.Effects of acute ingestion of a pre-workout dietary supplement with and without p-synephrine on resting energy expenditu…
- In 25 breast cancer survivors, 500 mg vitamin C plus vitamin E daily for 10 weeks alongside strength training did not reduce fatigue more than placebo.Effect of strength training and antioxidant supplementation on perceived and performance fatigability in breast cancer s…
- In 25 resistance-trained people, a week of a pre-workout drink containing 45 mcg B12 and other ingredients helped maintain some strength and lifting measures versus placebo but did not change cycling time trial performance.Short-Term Effects of a Ready-to-Drink Pre-Workout Beverage on Exercise Performance and Recovery.
- In 20 obese adults on a calorie-restricted diet, 500 mg of vitamin C daily for 4 weeks lowered self-reported fatigue and reduced heart rate and perceived exertion during exercise compared with placebo.Vitamin C status and perception of effort during exercise in obese adults adhering to a calorie-reduced diet.
- In 20 singers with mild vocal symptoms, a single 1000 mcg B12 injection did not improve voice fatigue or singing measures more than a placebo injection.Effect of Vitamin B12 Injection on the Vocal Performance of Professional Singers: A Randomized, Double-blind, Placebo-Co…
- In 20 iron-depleted women without anemia, 6 weeks of iron supplements, compared with placebo, reduced muscle fatigue during repeated knee-extension exercise and raised muscle strength later in the test.Iron supplementation improves progressive fatigue resistance during dynamic knee extensor exercise in iron-depleted, non…
- In 20 active women with low iron stores, 100 mg of daily iron for 8 weeks raised maximal oxygen uptake above the placebo group and lowered blood lactate after exercise, though the rise in endurance time was not statistically significant.Effects of iron repletion on VO2max, endurance, and blood lactate in women.
- In 18 healthy volunteers, 1000 mg a day of ascorbic acid for 8 days did not reduce physical fatigue during a long cycling task, while a different product did.Effects of Applephenon and ascorbic acid on physical fatigue.
- In 18 iron-depleted female runners, 8 weeks of oral iron raised iron stores but did not improve endurance time to exhaustion compared with placebo.Effect of iron supplementation on endurance capacity in iron-depleted female runners.
- In 17 people doing hard cycling at high altitude, a 3-week broad antioxidant capsule that included vitamin C did not improve performance; a different supplement combination did better than both this capsule and placebo.Effects of antioxidant supplementation on exercise performance in acute normobaric hypoxia.
- In a placebo-controlled trial of 16 iron-depleted female athletes, intramuscular iron injections raised serum ferritin but did not improve submaximal or maximal aerobic exercise performance compared with placebo over about 4 weeks.Effect of iron injections on aerobic-exercise performance of iron-depleted female athletes.
- In 15 people with chronic fatigue syndrome, injected liver extract with folic acid and vitamin B12 did not improve fatigue-related function more than placebo, and the placebo response was strong.Liver extract-folic acid-cyanocobalamin vs placebo for chronic fatigue syndrome.
- In 15 iron-deficient elite runners, a single 500 milligram intravenous iron injection improved iron levels for 4 weeks but did not improve time to exhaustion compared with placebo.Effect of Intravenous Iron on Aerobic Capacity and Iron Metabolism in Elite Athletes.
- In 14 healthy volunteers, 3000 mg a day of ascorbic acid for 8 days did not change physical fatigue during a long cycling task compared with placebo.Daily oral administration of crocetin attenuates physical fatigue in human subjects.
- In a placebo-controlled trial of 14 distance runners without clinical iron deficiency, three 100 mg intravenous iron injections over 4 weeks reduced perceived fatigue and mood disturbance by week 6, without improving running performance.Four weeks of IV iron supplementation reduces perceived fatigue and mood disturbance in distance runners.
- In 12 middle-aged triathletes during a 90-minute cycling session, taking vitamin C with glutathione improved energy-related metabolic and heart measures and lowered an oxidative stress marker compared with placebo, though vitamin C was not tested alone and this was a single acute session.Enhancing Supplemental Effects of Acute Natural Antioxidant Derived from Yeast Fermentation and Vitamin C on Sports Perf…
- In 7 well-trained male cyclists, a multinutrient supplement containing pyridoxine-alpha-ketoglutarate for 3 weeks did not extend time to exhaustion during cycling or speed recovery compared with placebo.Tricarboxylic-acid-cycle intermediates and cycle endurance capacity.
- In a randomized trial of pregnant people in their second trimester with iron deficiency anemia, a 27 mg iron tablet over 4 weeks raised hemoglobin as much as 100 mg ferrous ascorbate, improved dizziness, fatigue and palpitations more, and caused no side effects.Efficacy and safety of emulsified microsomal ferric pyrophosphate vs. Ferrous Ascorbate in pregnancy with iron-deficienc…
- In an open-label quasi-randomized trial of 1066 women with postpartum anemia, the herbal formula Ninjin'yoeito reduced fatigue over 4 weeks, while oral iron did not, although both raised hemoglobin by similar amounts.A quasi-randomized controlled trial of Ninjin'yoeito for the treatment of postpartum anemia and the prevention of postpa…
- In 155 young adults with low vitamin C, a 250 mg vitamin C tablet daily for 4 weeks only marginally improved mood until day 12, with effects weaker than kiwifruit, though mood improved in those with low starting vitamin C.Smartphone survey data reveal the timecourse of changes in mood outcomes following vitamin C or kiwifruit intervention i…
- In 134 patients after cerebral aneurysm embolization, adding glycerol fructose to routine vitamin B6 gave better neurological fatigue scores than B6 alone, so the benefit is from glycerol fructose rather than B6.Glycerol fructose combined with vitamin B6 is beneficial to postoperative recovery of patients with cerebral aneurysm.
- In 73 children and young people with mild thalassemia, 3 months of carnitine with or without 1 mg a day of folic acid reduced bone pain and muscle weakness, but the benefit was attributed to carnitine and fatigue was not reported separately.Determining and surveying the role of carnitine and folic acid to decrease fatigue in β-thalassemia minor subjects.
- In 61 hemodialysis patients, 100 mg of intravenous vitamin C after each session for 6 months did not improve energy-related quality of life or red blood cell production compared with no vitamin C.Effects of intravenous ascorbic acid on erythropoiesis and quality of life in unselected hemodialysis patients.
- In 12 healthy volunteers breathing low-oxygen air, one intravenous iron sucrose dose or saline placebo before 8 hours of low oxygen did not change maximal exercise capacity overall.Hypoxic pulmonary vasoconstriction does not limit maximal exercise capacity in healthy volunteers breathing 12% oxygen a…
- In 8 people with COPD, a single 2 g IV vitamin C dose compared with saline reduced quadriceps neuromuscular fatigue and lowered inflammatory C-reactive protein during exercise, but did not improve breathlessness or exercise tolerance.Ascorbate attenuates cycling exercise-induced neuromuscular fatigue but fails to improve exertional dyspnea and exercise…
- In 7 male triathletes, 6 weeks of a daily antioxidant capsule containing 600 mg ascorbic acid did not change maximal oxygen uptake or muscle fatigue compared with placebo.No effect of antioxidant supplementation in triathletes on maximal oxygen uptake, 31P-NMRS detected muscle energy metabo…
- In a Sri Lankan tea plantation, anemic workers given iron picked significantly more tea over one month than those given placebo, and their daily activity levels also rose.Iron-deficiency anaemia and its effect on worker productivity and activity patterns.
- In 214 outpatients with COVID-19, 8000 mg ascorbic acid for 10 days did not shorten symptoms, including fatigue, compared with usual care.Effect of High-Dose Zinc and Ascorbic Acid Supplementation vs Usual Care on Symptom Length and Reduction Among Ambulator…
- In 201 pregnant women with persistent iron deficiency, a single 1000 mg intravenous iron dose improved fatigue more than daily oral iron at weeks 3 and 6, and the women stayed non-anemic for longer.Intravenous ferric derisomaltose versus oral iron for persistent iron deficient pregnant women: a randomised controlled …
- In 85 women with severe fatigue after postpartum hemorrhage, a single 1200 milligram intravenous iron isomaltoside dose reduced physical fatigue more than oral iron over 12 weeks.Intravenous iron isomaltoside treatment of women suffering from severe fatigue after postpartum hemorrhage.
- In a single-arm study of 78 pregnant people with iron deficiency anemia, one 1000 mg intravenous dose of ferric derisomaltose raised mean hemoglobin by 1.3 g/dL by delivery and improved self-reported fatigue, with no major infusion reactions.Efficacy of Single-Dose Intravenous Ferric Derisomaltose for Iron Deficiency Anemia in Pregnancy.
- In an open-label trial of 40 head and neck cancer survivors, 100 mg vitamin C tablets daily for 8 weeks gave less fatigue relief than Tualang honey.Effects of Tualang Honey on Cancer Related Fatigue: A Multicenter Open-label Trial of H&N Cancer Patients.
- In 39 advanced cancer patients with cachexia, a 4-month combined treatment including 500 mg daily vitamin C improved fatigue scores and lowered inflammatory markers, but the study had no placebo group.A phase II study with antioxidants, both in the diet and supplemented, pharmaconutritional support, progestagen, and ant…
- In a small uncontrolled pilot of 23 iron-deficient women, a daily food-derived supplement that also contained vitamin C was taken for 8 weeks, and self-reported energy improved, though vitamin C alone was not tested and there was no placebo group.A Food-Derived Dietary Supplement Containing a Low Dose of Iron Improved Markers of Iron Status Among Nonanemic Iron-Def…
- In an uncontrolled pilot study of 23 young women with iron deficiency anemia, 160 mg daily of ferrous sulfate for 8 weeks lowered fatigue scores and improved muscle endurance, but did not improve aerobic fitness or muscle strength.Efficacy of 8-week oral iron supplementation on fatigue and physical capacity in young women with iron deficiency anemia…
- In 20 adolescent girls with iron deficiency and fatigue, intravenous iron sucrose led to clinically meaningful fatigue improvement in 19 of 20 at 6 weeks, with no control group.Intravenous iron therapy in non-anemic iron-deficient menstruating adolescent females with fatigue.
- In a small uncontrolled pilot of 10 homeless women taking alternate iron supplements for three months with nurse home visits, fatigue decreased and blood hematocrit rose, with few side effects.Side effects of alternative iron supplementation: a pilot study.
- In a survey of complementary medicine practitioners giving IV vitamin C (average 28 g every 4 days), 59 of 9,328 patients with data had lethargy or fatigue as a side effect, and most side effects were minor.Vitamin C: intravenous use by complementary and alternative medicine practitioners and adverse effects.
- In a chart review of 2142 people with fibromyalgia, 42.4% had vitamin B12 deficiency, and deficiency was linked to higher odds of fatigue (odds ratio 1.39) after adjusting for vitamin D.Association of Vitamin B12, Vitamin D, and Thyroid-Stimulating Hormone With Fatigue and Neurologic Symptoms in Patients …
- In 1676 people with colorectal cancer, higher blood levels of active vitamin B6 were linked with less fatigue and better quality of life six months after diagnosis, though this was not a supplement trial.Circulating B-vitamin biomarkers and B-vitamin supplement use in relation to quality of life in patients with colorectal…
- In 1,643 Spanish adults aged 65 and over followed for about 3.5 years, low dietary vitamin C intake was linked to a higher risk of frailty, which includes exhaustion, but this link was not statistically significant on its own.Low vitamin intake is associated with risk of frailty in older adults.
- In a 90-day follow-up of 923 Indonesian COVID-19 survivors, vitamin C combined with other micronutrients and favipiravir did not significantly change post-COVID symptoms, including fatigue, which was the most common symptom.Vaccination status, favipiravir, and micronutrient supplementation roles in post-COVID symptoms: A longitudinal study.
- In a retrospective study of 689 children without complaints, 23.2% had vitamin B12 deficiency and it was linked to vitamin D deficiency, but no supplement was tested for energy.Is There An Association Between Vitamin B12 Level and Vitamin D Status in Children?
- In a survey of 576 people in Syria who had COVID-19, 76.4% reported using vitamin C, but the survey did not measure whether vitamin C improved energy or fatigue, and fatigue was the most reported symptom.COVID-19 infected patients' experiences in Syria, and the role of the pharmacists during their infection.
- Older adults with fatigue had higher blood folic acid than those without fatigue, and lower vitamin D tracked with more fatigue; this study did not test folate supplements.Decrease in Serum Vitamin D Level of Older Patients with Fatigue.
- In 411 dentists and their wives, people who took little vitamin C reported about double the number of fatigue symptoms compared with those who took more.Daily vitamin C consumption and fatigability.
- In 335 older adults, vitamin B12 levels were not associated with frailty, and no supplement was tested.Association between serum vitamin B12 level and frailty in older adults.
- In 186 cancer patients with iron deficiency, intravenous iron was followed by better quality of life, fatigue scores, and physical function, though there was no control group.Impact of Iron-Deficiency Management on Quality of Life in Patients with Cancer: A Prospective Cohort Study (CAMARA Stud…
- In a retrospective German cohort of 125 breast cancer patients, adding intravenous vitamin C of 7.5 g for at least 4 weeks was associated with fewer treatment side effects, including fatigue, than no added vitamin C.Intravenous vitamin C administration improves quality of life in breast cancer patients during chemo-/radiotherapy and a…
- Women with fibromyalgia had lower vitamin B12 levels than 58 healthy women, and lower levels were linked to more tender points, though this study did not test supplements.Could ferritin, vitamin B12, and vitamin D play a role in the etiopathogenesis of fibromyalgia syndrome?
- In people with irritable bowel syndrome, lower vitamin B6 intake was linked with more fatigue, but this was an observational association within a diet study and not a test of vitamin B6 supplements.Poor intake of vitamins and minerals is associated with symptoms among patients with irritable bowel syndrome.
- In 101 people with relapsing multiple sclerosis, lower dietary folate intake was linked to higher fatigue scores, but this cross-sectional study cannot show cause.Dietary intake of nutrients and its correlation with fatigue in multiple sclerosis patients.
- In a retrospective chart review of 86 cancer patients given high-dose IV vitamin C (50 to 150 g per infusion), patients overall reported improved fatigue, pain, and mood, with temporary nausea and injection-site discomfort as the most common side effects.Retrospective Evaluation of Clinical Experience With Intravenous Ascorbic Acid in Patients With Cancer.
- In 67 adults with shingles, about 2 weeks of intravenous vitamin C alongside standard treatment was followed by reduced pain and less general fatigue, but the study had no placebo group.Intravenous vitamin C in the treatment of shingles: results of a multicenter prospective cohort study.
- In COVID-19 survivors with lingering fatigue, a multi-ingredient supplement containing vitamin B6 improved strength and walking performance over 8 weeks compared with a control group, but vitamin B6 was not tested alone.Effects of a New Multicomponent Nutritional Supplement on Muscle Mass and Physical Performance in Adult and Old Patients…
- Half of 60 people with chronic fatigue syndrome had low serum folate levels, but this survey did not test whether folate supplements improve energy.Serum folate and chronic fatigue syndrome.
- Vitamin B12 levels were normal in 55 people with primary fibromyalgia, who reported muscle fatigue as one of their most disabling symptoms.Primary fibromyalgia. A clinical and laboratory study of 55 patients.
- In a 7-day diary study of 20 adults with hypophosphatasia and 20 matched controls, vitamin B6 intake did not differ significantly between groups, and the study did not measure energy levels directly.Mineral Intake and Clinical Symptoms in Adult Patients with Hypophosphatasia.
- In a survey of 38 people with chronic fatigue syndrome or fibromyalgia, those who rated themselves much improved had taken more vitamin B12 injections and higher daily folic acid for longer, though this was not a controlled test.Response to vitamin B12 and folic acid in myalgic encephalomyelitis and fibromyalgia.
- In a retrospective review of 38 children with neurological symptoms of vitamin B12 deficiency, all recovered within one month of B12 supplementation; fatigue was among the symptoms but was not reported separately.Neurological symptoms of vitamin B12 deficiency: analysis of pediatric patients.
- In a study of 37 adults with pulmonary arterial hypertension, 29% had a functional vitamin B12 deficiency, but no supplement was tested, so the study does not show whether B12 improves energy.Nutritional status in pulmonary arterial hypertension.
- In a small case series of 20 infants with vitamin B12 deficiency, who were treated with cyanocobalamin, clinical and lab findings improved overall, though energy was not separately reported and the dose and duration were not stated.Vitamin B12 Deficiency in Infants.
- In 19 people with multiple sclerosis, those on a less inflammatory diet, which had higher vitamin B6 intake, reported more energy and fewer symptoms than those on a more inflammatory diet.Assessment of Functional Status in Patients with Multiple Sclerosis Based on the Inflammatory Potential of Their Diet.
- All 5 people with ALS who received methylcobalamin injections reported more energy and less fatigue, based on interviews; the dose was not stated.Patients' experiences with methylcobalamin injections in amyotrophic lateral sclerosis.
- In a case series of 19 adults with a rare bone disorder, four patients given empirical pyridoxine (vitamin B6) did not get symptom relief, including fatigue.Hypophosphatasia in Adults: Clinical Spectrum and Its Association With Genetics and Metabolic Substrates.
- In lymphoma survivors, a higher vitamin B6 breakdown marker was associated with a greater risk of chronic cancer-related fatigue, pointing to low-grade inflammation as a possible cause.Metabolic analysis of amino acids and vitamin B6 pathways in lymphoma survivors with cancer related chronic fatigue.
- This survey of hypothetical scenarios found people kept taking B12 for fatigue after a small symptom improvement, showing post hoc bias rather than any real effect of B12 on energy.Post Hoc Bias in Treatment Decisions.
- In 40 octogenarians with anemia and resistant heart failure, a combined treatment of erythropoietin and intravenous iron sucrose improved heart function, shortness of breath, and fatigue, though iron was not tested alone.Effect of correction of anemia with erythropoietin and intravenous iron in resistant heart failure in octogenarians.
- In 21 patients with inflammatory bowel disease who finished 8 weeks of oral liposomal iron, fatigue scores fell by an average of 9.2 points in an uncontrolled pilot study.Treatment of iron deficiency anemia with liposomal iron in inflammatory bowel disease: efficacy and impact on quality of…
Review Totals and Summary
Members Only312 reviews · 89% positive
Thorne's page shows 312 ratings in total, and the themes below come from the written reviews that could be read on that page, which were five short reviews from verified buyers. Reviews of other forms of the product were not part of this, and only the capsules are covered. What buyers praise most is the combination of ingredients in a single capsule. Michelle R. likes that vitamin C is included to increase absorption, and that B12 is also included so she does not need an additional pill. The most specific outcome comes from Kathleen S., who had low ferritin before starting and says it is now back up to normal. Carol M. says it has been great and plans to order again. Jewell W. and Sarah B. left brief positive comments, "Excellent" and "Really good product," without saying what they liked or how it worked for them. The page also carries its own AI-generated summary, labelled as produced from customer reviews. It says the product, formerly known as Ferrasorb, is praised for enhancing iron absorption and providing comprehensive nutritional support for anemia, and that customers report feeling better and more energetic. The popular topic tags on the page point the same way, with recurring words such as results, quality, feel and improvement. On the complaint side, the same AI summary says some people experience constipation or stomach issues, and "issues" and "stomach" also appear among the topic tags. None of the five visible written reviews mentions constipation or stomach problems, so those complaints rest on the summary text and tags, not on any review a reader can see. Beyond that, no complaints appear in the readable reviews. As for who it seems to suit, the feedback points to people managing low iron or anemia, such as the reviewer whose ferritin returned to normal, and to people who want iron, vitamin C and B12 in one capsule instead of taking separate pills. Repeat purchase is mentioned once, by Carol M. On form, taste and value, the reviewers say nothing about price in the visible text. None of the five written reviews complains about pill size or taste, but none praises them either, so nothing can be said about either point. Overall, the five written reviews are all positive, but only a few give detail: the convenience of the combined formula and one reported return of ferritin to normal. Five written comments against 312 ratings is a small sample of the written feedback, so the star distribution on the page is the better guide to overall satisfaction. The stomach and constipation concern is worth keeping in mind, since it appears in the page's summary even though no readable review describes it.
Biohacker Summary
Members Only10 of 10 recommend it
The panel is split on iron, the main ingredient: three of ten recommend it, one uses it, four are neutral, two warn about it, and one stopped. Those who recommend it point to brain function and dementia risk, keeping muscle, and women of reproductive age who are low in iron, and one panelist said testing first and replenishing only if levels are low makes sense. One panelist said they got less sore in training after starting an iron supplement, while another had low iron for 11 years and found no form of supplement raised it, so they stopped. The cautions are that too much iron may increase aging cells that drive inflammation, and that a diagnosis of anemia does not always mean you need more iron. Vitamin C, folate and vitamin B12 are smaller ingredients in this product, and the panel mostly speaks well of vitamin C, mainly for collagen.
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Dr. Eric Berg · Iron · neutral
- Identifies iron as the Achilles' heel of cancer, as it is needed for its DNA to replicate.
- Mentions that lemon is loaded with vitamin C, and when combined with coffee, vitamin C significantly increases the bioavailability of antioxidants in the coffee.
- Dr. Berg states that Vitamin C helps fight biofilms and is essential for making collagen in gums, teeth, and capillaries.
- Recommends Vitamin C as a cofactor, especially for collagen.
- States that high doses of vitamin C, like 2 to 4 grams, can greatly reduce inflammation and support the immune system.
- Notes that birth control pills deplete the body of folate, which is needed for the brain to make serotonin.
- Mentions that grass-fed liver has heme iron, the most bioavailable form of iron that prevents anemia.
- Highly recommends taking natural food vitamin C, about 500 mg, at the first sign of a cold.
- Dr. Berg warns that too much iron can be damaging to the body and advises focusing on food sources to avoid overconsumption.
- Dr. Berg lists pyridoxine hydrochloride as a synthetic vitamin to avoid.
- Recommends taking the active form of vitamin B6, pyridoxal-5-phosphate (P5P), for its benefits to the nervous system, including building the myelin sheath and protecting sensory nerve integrity.
- Notes that Vitamin B6 is intimately involved in the nervous system and may be behind sciatica and carpal tunnel syndrome.
- Recommends taking the natural form of vitamin B12, methylcobalamin, to support nerve regeneration, myelin production, and nerve growth factors.
- Notes that Vitamin B12 is intimately involved in the nervous system and may be behind sciatica and carpal tunnel syndrome.
Dr. Mark Hyman · Iron · neutral
- Mentions iron as an existing biomarker that plays a role in mental health, which Function Health includes in their measurements.
- Notes that taking folate can lower homocysteine levels, which has shown health benefits and physical improvements in brain scans in clinical trials.
- Notes that some people may need a little bit extra folate with a supplement.
- Recommends vitamin C as a basic supplement during detoxification to help with inflammation and detoxification.
- Dr. Hyman mentions vitamin C as an advanced therapy for skin repair.
- Mentions topical vitamin C as an antioxidant that can help skin with aging.
- Mentions that what they do when a cold comes on is not just vitamin C.
- Recommends ensuring adequate vitamin C intake on a regular basis for immune support, stating it's important for healthy immune function despite mixed data on its effectiveness for colds.
- Mentions that vitamin C was the very first vitamin discovered, isolated, and synthesized in 1932, and its deficiency caused scurvy.
- Recommends nutrient-dense foods rich in vitamin C, such as guavas and parsley, to reduce inflammation.
- Used intravenous vitamin C cocktails to help him detoxify and recover from chronic fatigue.
- Notes that a woman patient had very low iron.
- Optimized a child's nutrient status with folate, as the child had low folate levels and was not eating greens.
- Optimized a child's nutrient status with vitamin B6, as the child had low B6 levels.
Siim Land · Iron · neutral
- Mentions that iron is a mineral necessary for making collagen.
- Recommends taking vitamin C with collagen to support joint collagen synthesis.
- States that vitamin C is needed for initiating collagen synthesis and that higher vitamin C intake appears to increase vitamin C content in the skin.
- Lists sauerkraut and fruit as sources of Vitamin C.
- Notes that Vitamin C is one of several supplements with human evidence.
- States that excess iron promotes oxidative stress and inflammation, which increases heart disease risk.
- Notes that researchers found vitamin C alleviates ferro-aging, a process of iron overload and lipid peroxidation that drives aging, and that it directly inhibited ACSL4, a protein driving ferro-aging.
- States that Vitamin C has a central role in aging and longevity, and that in monkeys, oral vitamin C slowed ovarian aging during a 3.3-year study.
- States that vitamin C is one of the most important vitamins for staying healthy and aging well, and that intakes of 200 to 400 mg a day from food or supplements largely saturates plasma and neutrophils in most healthy adults. He also recommends spreading out the vitamin C across the day to avoid oversaturation.
- Mentions vitamin C in comparison to topical melatonin for oxidative defense, stating that melatonin would compete but is not as broadly validated clinically.
- Was found to be vitamin C deficient by True Health and Mayo Clinic tests, and now addresses this by eating one extra kiwi fruit daily.
- States that the biggest evidence for multivitamin is that it improves cognition and enhances episodic memory in elderly people, who tend to have worse diets and are more likely to be deficient.
- Created Microvitamin, a supplement that bundled all the supplements he was taking, to help fund his a med trial.
- Notes that iron deficiency is found in children with premature graying of hair and that some people get gray hair due to iron deficiency.
Thomas DeLauer · Iron · neutral
- Compares iron content in spinach (2.7mg) and beef (2.6mg), but emphasizes that beef's heme iron absorbs at about 25%, while spinach's non-heme iron absorbs at 2-8%.
- Recommends taking vitamin C along with collagen about an hour before a workout for connective tissue benefits.
- Uses vitamin C as part of their immunity duo, stating it is important for boosting the immune system, especially during cold and flu season.
- Recommends Vitamin B12 for mental health and mood, explaining its role in myelination and neurotransmitter production. They specifically recommend a liposomal and micellar form of methylcobalamin B12 for better absorption and to avoid toxicity.
- Recommends consuming vitamin C to aid in NADPH recycling, which is necessary for glutathione to be reused after neutralizing oxidative stress.
- Takes Purity's liquid liposomal vitamin C for immune support and overall wellness, finding it easy to add to water, juice, or take straight up due to its good taste.
- Compares the Vitamin C content of oranges (53mg) to guava (228mg), noting guava has 4x more.
- States that collagen synthesis is vitamin C dependent, in the context of glowing skin.
- Recommends Vitamin C for sleep, noting that intake in the range of 125 to 200 mg per day is associated with a lower risk of sleep disorders and sleep apnea, with the benefit plateauing beyond this range.
- Recommends iron from meat, specifically red meat and beef liver, stating that it is a crucial part of the mechanistic triad for thyroid hormone function and is iron-dependent for iodine incorporation into thyroid hormone.
- Recommends consuming a little bit of vitamin C, such as a couple of berries or kiwi, along with flavanol-rich cocoa to help the delicate flavanols hold up and prevent oxidation in the gut.
- Explains that vitamin C improves the ability of neutrophils to engulf bacterial infections, and that they have a greater ability to engulf larger infections.
- Recommends using a multivitamin to ensure adequate micronutrient intake, especially when wholesome food is less available.
- Mentions that a single serving of sardines provides vitamin B12 at something like three to four times the daily needs.
Andrew Huberman · Iron · recommends
- States that Iron is one of the critical nutrients with the best evidence for cognitive function and reducing the risk of dementia.
- Takes a multivitamin every day for longevity.
- Recommends AG1, a vitamin, mineral, and probiotic drink, and notes that for a limited time, a subscription comes with additional supplements.
- States that a deficiency in vitamin B12 can be terrible and lead to chronic fatigue-like syndromes, as many parts of mitochondria require B vitamins.
- Warns that excess iron will increase the number of senescent cells in the body, which accumulate as people get older and cause inflammation and cancer. He notes that people who are healthy and have a fairly vegetarian diet often have slightly low iron levels but super amounts of energy.
- Takes an extra gram of vitamin C a day for its effects on immunity and potential synergy with collagen.
- Found the Met RX Big 100 Bar to be 'magic' on the trail because it's a hunk of calories with protein and fortified with vitamins and minerals, despite being something they would never eat in normal life.
- Started taking AG1 in 2012 and still takes it every single day to ensure he meets his quota for daily vitamins and minerals and to support gut health, which is critical for proper brain function, immune system, and neurotransmitter production.
- Notes that about 50% of the population is iron deficient.
- Mentions that the podcast will review the role of iron in treating depression.
- States that B12, folate, and iron are essential to mitochondrial function and if deficient, mitochondria will not function properly, which is consistent with the mitochondrial theory of neuropsychiatric disorders.
- States that B12, folate, and iron are essential to mitochondrial function and if deficient, mitochondria will not function properly, which is consistent with the mitochondrial theory of neuropsychiatric disorders.
- Has been taking AG1 daily since 2012 because it is the highest quality and most complete foundational nutritional supplement, ensuring he gets all necessary vitamins, minerals, and micronutrients for daily health.
- Has been drinking AG1 since 2012, finding it difficult to get enough vitamins, minerals, micronutrients, and adaptogens from diet alone. He finds that taking AG1 daily improves all aspects of his health, including physical and mental health, performance, recovery from exercise, and immune system strength, and also notices more mental clarity and energy.
Ben Greenfield · Iron · recommends
- Recommends testing for and replenishing iron if levels are low, as it can affect the ability to maintain or preserve muscle, especially for those on GLP-1s.
- States that vitamin C is extremely important for collagen turnover and cites orthopedic data showing that 500 mg to 1 g of vitamin C can reduce the rate of complex regional pain in total knee replacements and wrist fractures.
- Mentions vitamin C as part of a bare-minimum protocol.
- Recommends methylfolate as an active form of folate that the body can use directly without conversion.
- Notes that while vitamin C has significant value, the optimal dose is a vexed question, and high doses might not always be beneficial, potentially blunting the hormetic effects of exercise.
- Notes that IV vitamin C has been used for decades for cancer patients with almost no standardization and that he receives many questions about its effectiveness and combination with chemo.
- Recommends Vitamin C for skin repair post-tattoo.
- Recommends bioavailable folate, not synthetic folic acid, as folate deficiencies seem to impact hearing health in older individuals.
- Recommends getting vitamin B12 tested and supplementing if deficient, as B12 deficiency can cause damage to the myelin coating around nerves, including cochlear nerves, and improve tinnitus severity scores.
- Notes that one can eat iron-rich foods or supplement with iron, but still feel exhausted if iron is not the missing piece, emphasizing that focusing on a single mineral in isolation can support a number on a lab test rather than the system itself.
- Mentions iron as a common deficiency.
- Recommends introducing methylfolate into the diet to address high homocysteine levels.
- Recommends a nutritious diet including iron, as it is critical for brain development.
- Does not agree that ascorbic acid is vitamin C, comparing it to calling chaff wheat, and notes that it is made from genetically modified cornstarch or corn syrup byproducts using solvents.
Bryan Johnson · Iron · stopped
- Has had low iron for 11 years and despite eating meat and trying all forms of iron supplementation at different times and sequences, none of it worked to raise his iron or ferritin levels.
- Had low iron for 11 years, with ferritin averaging 38 ng/mL, and has finally boosted it back to healthy levels.
- States that Blueprint essential capsules and soft gels are packed with key vitamins and minerals needed for strong bone health.
- Uses Vitamin C as an example of how it would be great if people knew that when they took it, it had a measurable amount and wasn't polluted, which is what Brian ensures with his products.
- Applies vitamin C after showering.
- Takes 10 milligrams of heme iron to get his iron levels up, as they are borderline.
- Takes 250 milligrams of Vitamin C.
- Recommends adequate Iron for hair health, noting it is in the Blueprint stack.
- Recommends supplementing with iron for brain health for both the mother and the baby during pregnancy.
- Recommends Vitamin C for skin health, noting it's good to pair with collagen peptides and is included in the Blueprint stack.
- Bryan Johnson takes Vitamin C daily as part of his Longevity Mix, which is an antioxidant-rich essential vitamin that supports immune function and metabolic energy.
- He uses Vitamin C, typically in a serum, in the morning for skin health.
- Recommends supplementing with folate for brain health for both the mother and the baby during pregnancy.
Dave Asprey · Iron · warns
- Warns that if a doctor diagnoses anemia, one should not assume they just need more iron, as low hemoglobin doesn't always mean low iron and the issue can sometimes be how well the body is using iron.
- Recommends taking vitamin C for better skin health.
- States that folate can affect how the body responds to a supplement.
- States that currently, he is only taking vitamin C and vitamin D.
- Dave Asprey reflects on how new research clarifies the mechanism behind IV vitamin C's anti-cancer effect, vindicating a decades-old idea that was dismissed for the wrong reasons.
- Recommends methylfolate as a better option than folic acid.
- Notes that plain Vitamin C isn't enough and that most people never think to check for a specific ingredient that makes it work.
- Dave Asprey recommends taking maybe a gram of vitamin C a day in divided doses, noting that plasma levels peak around 250 milligrams twice a day.
- Recommends Qualia Vitamin C Plus, highlighting its combination of seven forms of vitamin C with 250 mg of citrus bioflavonoids, which helps with absorption and use for building collagen and a strong immune system.
- Warns that taking too much vitamin C can raise oxalate levels, emphasizing that everything has risk and reward.
- States that Vitamin B12 is extremely important for every kind of brain function and recommends ensuring B12 levels are optimal, around 500, not just barely above normal.
- Notes that when energy intake is too low for training demand, nutrient intake often falls short, especially for iron, which is associated with impaired recovery.
- Recommends Vitamin C as the real biological fix for deep focus issues, explaining how the brain hoards it at levels 100 times higher than blood and how to bypass the blood-brain barrier.
- Dave Asprey notes that 80% of their clients have a problem absorbing certain forms of folate, and when the exact form of folate or folinic acid is dialed in, clients experience shifts, with the brain waking up as one of the first improvements.
Dr. Rhonda Patrick · Iron · uses
- Recently found out he needed to get on an iron supplement and noticed he gets less sore in his training after taking it.
- Recommends ensuring adequate methyl folate intake, ideally through a prenatal vitamin, for women preparing for IVF.
- Lutein and zeaxanthin can also be obtained from certain multivitamins.
- Recommends nutrients like vitamin C for men to prioritize sperm mitochondrial health.
- Dr. Rhonda Patrick's daughter chugs an Emergency fizzy drink in the morning to ensure she gets some vitamin C and micronutrients before school.
- Choosing a multivitamin that includes lutein and zeaxanthin ensures you get meaningful amounts every day.
- Advises that menstruating women should ensure they are getting enough iron.
- Notes that ~35% of Americans are low in vitamin C.
- Recommends increasing vitamin C intake if concerned about skin aging, noting it is an essential cofactor for collagen synthesis.
- Warns that Vitamin B12 enhances light's melatonin-suppressing effects and should be avoided too close to bedtime.
- Suggests avoiding a multivitamin if it contains biotin before a testosterone blood test to prevent confounding results.
- Multiple randomized controlled trials show older adults taking a standard multivitamin (like Centrum Silver) had measurable improvements in processing speed, cognition, and episodic memory.
- Notes that dark leafy greens are a great source of folate.
- Currently takes the Pure Encapsulations O.N.E Multivitamin.
Peter Attia · Iron · recommends
- Recommends iron supplements for women of reproductive age who are iron deficient.
- Recommends vitamin C as an important molecule for skin, noting its role as a precursor for collagen synthesis, a powerful antioxidant, and a regulator of complexion for even skin tone.
- Tried a vitamin C serum mixed with ferulic acid but stopped using it because she hated the smell. She notes that topical application of vitamin C far exceeds the levels achievable by ingestion for skin benefits.
- Notes that deficiencies in certain vitamins and minerals, such as iron, can be a cause of hair loss in women.
- Notes that deficiencies in certain vitamins and minerals, such as B12, can be a cause of hair loss in women.
- States that vitamin C deficiency is associated with an elevated risk of cataract, but supplementation to supranormal levels has not been shown to protect against cataract formation.
- Mentions the elimination of scurvy through the work of James Lind and the eventual understanding that it was due to vitamin C, initially thought to be just citrus.
- Highlights folate supplementation as a significant practical progress in nutrition science, which has radically reduced spinabifida.
- Delves into the crucial yet often overlooked topic of iron and iron deficiency.
- Explains that humans consume about 10 to 20 milligrams of iron per day, absorbing roughly 10% of that, which is 1 to 2 milligrams per day, perfectly offsetting the 1 to 2 milligrams lost daily.
- Peter emphasizes the importance of consuming an adequate amount of iron daily to prevent deficiency.
- Takes Jarrow methylfolate to keep homocysteine levels below nine, taking the lower of two available strengths once a day.
- Takes Jarrow methylfolate, a methylated version, once a day at the lower of two strengths, to keep homocysteine levels below nine.
- Mentions that in a mouse model for obesity, the amount of folate given to the mother mouse during pregnancy affects the epigenetics of her offspring, leading to changes in coat color and obesity.
RAL Summary
Members OnlyTier 2 for Energy
More Details
Members OnlyBody systems · Combine with · Possible side effects
Body systems: Blood and circulatory system, Nervous system, Digestive system
Combine with: For its intended purpose of supporting iron levels and energy, Ferrasorb pairs well with vitamin B12 and folate (methylcobalamin and methylfolate) for healthy red blood cell production, and with vitamin A or copper in modest amounts to support iron metabolism. Taking it away from calcium, magnesium, zinc, coffee, tea, and high-fiber foods improves absorption. If iron causes constipation, magnesium glycinate or extra fiber and fluids may help. Only supplement iron if blood tests (ferritin, serum iron, TIBC) confirm a need. For occasional heartburn, look at a separate product such as calcium carbonate or magnesium/aluminum antacids, alginate (sodium alginate), or DGL licorice, and take iron on a different schedule from antacids because they reduce iron absorption.
Possible side effects: The store page's own summary and topic tags mention constipation or stomach issues for some buyers, though none of the readable reviews describes them. The studies given report no side effects.
Supplement Facts
Vitamin C 15 mg · Vitamin B6 5 mg · Folate 667 mcg DFE
| Vitamin C | 15 mg | |
| Vitamin B6 | 5 mg | |
| Folate | 667 mcg DFE | |
| Vitamin B12 | 300 mcg | |
| Iron | 36 mg |
Other ingredients: Hypromellose, Microcrystalline Cellulose, Leucine, Silicon Dioxide.
Directions: Suggested Use: Take 1 capsule one to three times daily or as recommended by your healthcare practitioner.
Barcode (UPC) 693749750031 · Label source: NIH label database · Report a label change
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Graded November 6, 2026 by the Reverse Age Lab evidence engine, from human studies, real reviews and our biohacker panel. How we grade. Is this medical advice? No. Rala organizes the published evidence; go over any change with your doctor, especially if you take meds.
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