Nature Made Zero Sugar‡ Hair Skin Nails Gummies Review
Tier ⓘ
Tier 4 · Rank 24
Tier 4 · Emerging. A promising mechanism or animal data, with thin human evidence so far. Rank 24 within Tier 4 for Circulation; 48 of 51 overall. Tiers run from 1, the strongest evidence, to 5. How we grade →
Evidence ⓘ
15 /100
How strongly the evidence says this product works: human studies count most, then real reviews, then our biohacker panel.
Biohacker Mentions
0 of 10
We don’t sell supplements. We help you make decisions and get the best price.
Lowest prices
We may earn a commission from some store links. How we choose.
Finding the lowest prices at the stores now. This takes a few seconds.
Products with nearly the same formula (Matched on the main ingredients)
Study, Trial or Testing Result Summary
Members Only68 human studies · 43 improved
26 of these 68 human studies gave the ingredient by drip, not by mouth.
68 human studies43 improved12 no effect10,447 people studied
This gummy is made for hair, skin and nails, not for blood flow, and its vitamins are far below the amounts studied for blood vessel health. Vitamin C is present at 15 mg, while studies that helped used 500 mg daily. At that higher dose it improved artery widening in people with heart artery disease [1], reduced artery stiffness in adults with type 2 diabetes [2] and restored vessel widening in obese children [3]. Results are mixed overall, and a large review found no overall effect on artery stiffness [4]. Vitamin E is present at 6.8 mg, while a helpful trial used 600 mg daily, which improved arm artery widening in adults with type 2 diabetes [5]. A review found suggestive but not consistent benefit for the blood vessel lining [6]. Biotin is the main ingredient, at 2500 mcg. The only blood flow study gave it inside a vitamin and mineral mix at 200 mcg and found no change in small vessel blood flow [7]. Because of these trace doses and thin biotin evidence, this product is not expected to help blood flow. Animal and cell studies are never counted.
See all 68 studies →Hide the studies
- In seven controlled trials with 872 patients having heart artery procedures or bypass surgery, vitamin C given by vein lowered peak troponin by about 43% and peak CK-MB by about 14% and reduced oxidative stress markers.Vitamin C may reduce troponin and CKMB levels after PCI and CABG: a meta-analysis.
- In six studies of 160 people with sleep apnea, antioxidant treatments including vitamin C improved blood vessel dilation by about 2.16 percentage points and reduced oxidative stress, but vitamin C was not analyzed separately.Antioxidant therapies for obstructive sleep apnea: A systematic review and meta-analysis.
- A review of 10 systematic reviews covering 6409 people found contrasting results for vitamin C on blood vessel function, with no overall effect on arterial stiffness and only limited benefit in some subgroups.Limited evidence for a beneficial effect of vitamin C supplementation on biomarkers of cardiovascular diseases: an umbre…
- In eight trials with 1185 patients, vitamin C given by vein before a heart artery procedure reduced heart injury markers, oxidative stress and inflammation, while improvements in heart pumping function were inconclusive.Vitamin C for Cardiac Protection during Percutaneous Coronary Intervention: A Systematic Review of Randomized Controlled…
- A review of randomized trials in people with diabetes or metabolic syndrome found vitamin C, mostly 1,000 mg daily for 4 weeks to 12 months, lowered cholesterol and inflammation and was consistent with better endothelial function and blood flow.Vitamin C intake potentially lowers total cholesterol to improve endothelial function in diabetic patients at increased …
- A review of 32 meta-analyses found suggestive evidence that vitamin E supplements improve blood vessel lining function and lower C-reactive protein, though the evidence was not strong enough to be called consistent.Vitamin E and Multiple Health Outcomes: An Umbrella Review of Meta-Analyses.
- In 75 adults with type 2 diabetes, 4 months of a daily supplement mix containing 200 mcg of biotin did not change capillary blood flow compared with placebo, though nerve symptom scores improved.Improving neuropathy scores in type 2 diabetic patients using micronutrients supplementation.
- In 46 people with high cholesterol, a single 2 g dose of ascorbic acid lengthened the duration of forearm reactive blood flow after two hours versus placebo but did not raise peak flow.Effect of ascorbic acid on forearm reactive hyperaemia in patients with hypercholesterolaemia.
- In 70 healthy young adults exposed to simulated night train noise, vitamin C improved blood vessel dilation in women but not in men.Acute Exposure to Simulated Nocturnal Train Noise Leads to Impaired Sleep Quality and Endothelial Dysfunction in Young H…
- In 46 people with coronary artery disease, 500 mg of vitamin C daily for 30 days improved blood vessel widening in the arm artery (about 8.6% to 9.0% vs unchanged with placebo), and a single 2 g dose also helped.Long-term ascorbic acid administration reverses endothelial vasomotor dysfunction in patients with coronary artery disea…
- In 42 people with kidney disease, a one-time vitamin C infusion produced only a non-significant trend toward better artery dilation in the placebo group; the trial's main test was a different drug (rilonacept), not vitamin C.IL-1 Inhibition and Vascular Function in CKD.
- In 40 adults with type 2 diabetes, 600 mg of vitamin E daily for 8 weeks improved brachial artery widening and lowered oxidative stress compared with placebo.Chronic vitamin E administration improves brachial reactivity and increases intracellular magnesium concentration in typ…
- In 39 people with high blood pressure, 500 mg of vitamin C daily for one month did not improve blood vessel widening compared with placebo.Effect of ascorbic acid treatment on conduit vessel endothelial dysfunction in patients with hypertension.
- In 39 people with heart failure, 4 grams of vitamin C daily for 4 weeks improved a blood vessel measure but worsened muscle energy handling during exercise.Chronic oral ascorbic acid therapy worsens skeletal muscle metabolism in patients with chronic heart failure.
- A single intravenous vitamin C infusion lowered elevated blood flow in the brain in people with Fabry disease and in healthy controls, though the placebo group responded more slowly.Ascorbate decreases Fabry cerebral hyperperfusion suggesting a reactive oxygen species abnormality: an arterial spin tag…
- In 26 healthy men and 8 men with peripheral artery disease, vitamin C infused into the arm during reperfusion after ischemia prevented the loss of blood vessel widening seen with placebo.Intra-arterial vitamin C prevents endothelial dysfunction caused by ischemia-reperfusion.
- In 31 people with leg artery disease, vitamin C given before maximal walking prevented the drop in artery widening and the rise in oxidative stress seen after exercise in those given saline.Vitamin C prevents endothelial dysfunction induced by acute exercise in patients with intermittent claudication.
- In 30 adults with type 2 diabetes, 500 mg of vitamin C daily for 4 weeks lowered blood pressure and reduced arterial stiffness, while placebo had no effect.Ascorbic acid reduces blood pressure and arterial stiffness in type 2 diabetes.
- In 30 overweight adults with high cholesterol, 500 mg of vitamin C taken daily with vitamin E for 6 weeks did not significantly improve blood vessel widening compared with placebo.Oats, antioxidants and endothelial function in overweight, dyslipidemic adults.
- In 30 heart surgery patients on heart-lung bypass, one intravenous vitamin C dose given during rewarming reduced a rise in reactive oxygen molecules and improved red blood cell flexibility compared with placebo.Vitamin C supplementation attenuates oxidative stress and improves erythrocyte deformability in cardiac surgery with car…
- In 29 salt-resistant adults on a high-salt diet for 7 days, local infusion of ascorbic acid restored skin blood vessel dilation that the high-salt diet had reduced.Apocynin and Tempol ameliorate dietary sodium-induced declines in cutaneous microvascular function in salt-resistant hum…
- A single intravenous 1,000 mg dose of vitamin C improved arm blood vessel widening in people with type 1 diabetes and in regular smokers, compared with saline, in a study of 24 people where uric acid was the main test.Uric acid restores endothelial function in patients with type 1 diabetes and regular smokers.
- In a double-blind trial of 21 obese children aged 8 to 12, 500 mg of vitamin C daily for 45 days lowered mean blood pressure and restored forearm blood vessel dilation during mental stress, while placebo did not.Vitamin C restores blood pressure and vasodilator response during mental stress in obese children.
- In 19 healthy adults, a single 2 g oral dose of vitamin C shortened the blood vessel dysfunction caused by smoking one cigarette, recovering to baseline levels faster than placebo.Oral administration of ascorbic acid attenuates endothelial dysfunction after short-term cigarette smoking.
- In 18 people with metabolic syndrome, a single 1 g intravenous vitamin C infusion improved artery widening compared with placebo and counteracted the rise in an oxidative stress marker.Oxidative stress-mediated arterial dysfunction in patients with metabolic syndrome: Effect of ascorbic acid.
- In 17 people with resistant high blood pressure and high cholesterol, 500 mg of vitamin C daily for 8 weeks did not change blood pressure, cholesterol or artery widening compared with placebo, while a med did.Read the study on PubMed (15609886) →
- In 16 healthy women, taking a lutein complex containing 500 mg of vitamin C daily for three weeks increased blood flow in the retina of the eye and lowered diastolic blood pressure compared with placebo, though the effects cannot be attributed to vitamin C alone because it was combined with other ingredients.Lutein Complex Supplementation Increases Ocular Blood Flow Biomarkers in Healthy Subjects.
- In 14 overweight men, a single 3 g intravenous ascorbic acid infusion reduced oxidative damage and vascular remodeling markers during mental stress compared with placebo.Ascorbic acid inhibits vascular remodeling induced by mental stress in overweight/obese men.
- In 13 kidney transplant recipients, a single 2,000 mg oral dose of vitamin C improved the widening of blood vessels in the arm after blood flow was increased, compared with placebo, measured 2 hours after dosing.Vitamin C improves endothelial dysfunction in renal allograft recipients.
- In 12 healthy young adults, intra-arterial vitamin C during a single session of forearm exercise in high oxygen blocked the drop in forearm blood flow only in the subgroup most affected by high oxygen, and had no effect in the other subgroups.Effect of vitamin C on hyperoxia-induced vasoconstriction in exercising skeletal muscle.
- In 11 men sitting for 3 hours, taking 1 g plus 500 mg of vitamin C prevented the usual decline in artery flow-mediated dilation seen when sitting without it.Antioxidant vitamin C prevents decline in endothelial function during sitting.
- In a crossover study of 10 healthy adults, 2 g of oral vitamin C did not prevent the drop in endothelial-dependent blood vessel dilation caused by methionine-induced raised homocysteine.The effect on endothelial function of vitamin C during methionine induced hyperhomocysteinaemia.
- In 8 people with high blood pressure, vitamin C infused directly into an artery improved blood vessel widening, and 2 months of a med also improved it.Read the study on PubMed (12164090) →
- In 8 male smokers, 1 g of vitamin C daily for about 5 weeks did not improve blood vessel widening or clot-dissolving activity compared with placebo.Vitamin C has no effect on endothelium-dependent vasomotion and acute endogenous fibrinolysis in healthy smokers.
- Vitamin C applied to the skin after UV exposure, alone or combined with vitamin E and melatonin, did not significantly reduce sunburn redness or change skin blood flow.Effect of topical antioxidants on UV-induced erythema formation when administered after exposure.
- In healthy men, a single 2 g oral dose of vitamin C reduced arterial stiffness and clotting-cell aggregation compared with placebo, which showed no change.Oral vitamin C reduces arterial stiffness and platelet aggregation in humans.
- In a double-blind trial in people with heart failure, vitamin C lowered circulating apoptotic microparticles (signs of blood vessel cell death) compared with placebo, which had no effect.Vitamin C inhibits endothelial cell apoptosis in congestive heart failure.
- In people with heart failure from blocked heart arteries, infused vitamin C was tested alone and with L-arginine on nervous system control of blood vessels, but the abstract does not clearly report the effect of vitamin C alone.Influence of L-arginine and vitamin C on the autonomic nervous system in chronic heart failure secondary to ischemic car…
- In a randomized, double-blind crossover study of healthy men, a single 2 g intravenous dose of vitamin C given before a two-hour high-blood-sugar challenge prevented the rise in arterial stiffness and pulse wave reflection seen with placebo.Protective effects of ascorbic acid on arterial hemodynamics during acute hyperglycemia.
- A single 2 gram oral dose of vitamin C made skin blood vessels constrict more strongly to cold, which reduced skin blood flow.Oral vitamin C enhances the adrenergic vasoconstrictor response to local cooling in human skin.
- In 75 men with coronary artery disease, vitamin C infused into the forearm artery raised baseline forearm blood flow and acetylcholine-stimulated flow in those with high inflammation (CRP) but not those with low CRP.C-reactive protein levels determine systemic nitric oxide bioavailability in patients with coronary artery disease.
- In 50 healthy adults, a single dose of vitamin E with a high-fat meal kept blood flow response from dropping, as oatmeal did, while wheat cereal let it fall by 13.4%.Effects of oat and wheat cereals on endothelial responses.
- In 46 people with coronary artery disease, a single 2 g dose of vitamin C improved blood vessel dilation within 2 hours in those with poor baseline function (2.0% to 9.7%), while placebo had no effect.Ascorbic acid reverses endothelial vasomotor dysfunction in patients with coronary artery disease.
- In 39 lean, obese, and metabolic syndrome adults, an acute infusion of ascorbic acid did not change how quickly or how much blood vessels widened during arm exercise.Exercise-mediated vasodilation in human obesity and metabolic syndrome: effect of acute ascorbic acid infusion.
- In 23 healthy young men, intra-arterial vitamin C reversed the angiotensin II-related weakening of endothelium-dependent forearm blood vessel dilation, while vitamin C alone did not change it.Vitamin C improves attenuated angiotensin II-induced endothelium-dependent vasodilation in human forearm vessels.
- In 11 people with high cholesterol and 12 healthy controls, vitamin C infused directly into the arm improved blood vessel widening in response to methacholine in the people with high cholesterol, with no change in controls.Vitamin C improves endothelium-dependent vasodilation in forearm resistance vessels of humans with hypercholesterolemia.
- In 10 people with type 2 diabetes, vitamin C infused into the arm artery improved the widening of forearm blood vessels in response to methacholine, while it had no effect in 10 non-diabetic controls.Vitamin C improves endothelium-dependent vasodilation in patients with non-insulin-dependent diabetes mellitus.
- In 10 chronic smokers, vitamin C infused into the arm artery markedly improved the widening of forearm blood vessels in response to acetylcholine, while it had no effect in 10 non-smoking controls.Antioxidant vitamin C improves endothelial dysfunction in chronic smokers.
- In 11 smokers, vitamin C restored heart muscle blood flow reserve that was reduced compared with 8 non-smokers, while it had no effect in the non-smokers.Coronary heart disease in smokers: vitamin C restores coronary microcirculatory function.
- In 11 people with postural tachycardia syndrome and 8 healthy controls, ascorbate given through the skin and through a vein increased blood flow in the skin and limbs and raised cardiac output by about 40% after infusion.Ascorbate improves circulation in postural tachycardia syndrome.
- In 8 adults with Down's syndrome, who had weaker blood vessel function than 9 controls of similar age, vitamin C gave only a slight improvement in endothelium-dependent blood vessel widening that was not statistically significant; the dose and duration are not stated in the abstract.Endothelial cell function in patients with Down's syndrome.
- In 15 overweight or obese men, a 3 gram intravenous vitamin C infusion increased blood vessel dilation 60 minutes after a mental stress task, although it did not change the response at 30 minutes.Mental stress induces endothelial dysfunction by AT1R-mediated redox imbalance in overweight/obese men.
- In 14 patients with essential hypertension, an infusion of vitamin C into the arm improved blood vessel widening in response to acetylcholine, while healthy controls showed no change.Vitamin C improves endothelium-dependent vasodilation by restoring nitric oxide activity in essential hypertension.
- In 10 healthy young men, a high-fat meal with 800 IU of vitamin E prevented the drop in arm artery widening seen after the same high-fat meal without vitamin E.Postprandial hypertriglyceridemia-induced endothelial dysfunction in healthy subjects is independent of lipid oxidation.
- In healthy people, an infused antioxidant (vitamin C) fully restored the artery widening that high insulin had impaired over a 4-hour clamp, while vitamin C alone did not change artery widening in saline controls.Insulin causes endothelial dysfunction in humans: sites and mechanisms.
- In healthy people made temporarily hyperglycemic, vitamin C infused into the arm artery restored the blood vessel widening response to methacholine that hyperglycemia had reduced.Ascorbate restores endothelium-dependent vasodilation impaired by acute hyperglycemia in humans.
- In healthy men, infusing vitamin C into the forearm prevented angiotensin II from weakening the blood vessel dilation caused by a nitrate drug.Angiotensin II attenuates the vasodilating effect of a nitric oxide donor, glyceryl trinitrate: roles of superoxide and …
- In people with metabolic syndrome during high insulin levels, vitamin C improved the blood vessel dilation response to acetylcholine, though adding the drug infliximab did not further improve it.Tumor necrosis factor-alpha antagonism improves vasodilation during hyperinsulinemia in metabolic syndrome.
- In an open-label study of 9 adolescents with type 1 diabetes, six weeks of combined vitamin C and vitamin E did not change endothelial function or related blood markers.Effect of Vitamins C and E on Endothelial Function in Type 1 Diabetes Mellitus.
- In 281 people with coronary artery disease followed for about 4.5 years, poor blood vessel widening predicted later heart events, and vitamin C raised widening more in those who had events.Endothelial dysfunction, oxidative stress, and risk of cardiovascular events in patients with coronary artery disease.
- In 58 healthy men, a single vitamin C infusion improved artery widening only in middle-aged and older men with low testosterone, and had no effect in young men or older men with higher testosterone.Oxidative Stress and Inflammation Are Associated With Age-Related Endothelial Dysfunction in Men With Low Testosterone.
- In 135 people with brain circulation disorders, alpha-tocopherol ranked below essenciale and above unithiol in effectiveness at relieving free-radical damage; the dose was not stated.[Criteria of pharmacologic effectiveness of antioxidant and membrane-stabilizing drugs in various disorders of cerebral …
- In 45 young adults (lean, obese, or with metabolic syndrome), vitamin C infused into the forearm artery increased blood flow responses to vessel-dilating drugs across all groups, with no control group on placebo.Microvascular function in younger adults with obesity and metabolic syndrome: role of oxidative stress.
- In 14 young and 14 older adults, a short vitamin C infusion raised forearm blood flow about 34% during continuous exercise in older adults only, and did not change the quick blood flow response to single muscle contractions in either group.Endothelium-dependent vasodilatation and exercise hyperaemia in ageing humans: impact of acute ascorbic acid administrat…
- In 11 young habitual hookah smokers, a single vitamin C infusion raised blood vessel dilation at baseline and prevented the drop in dilation caused by 30 minutes of e-hookah vaping.Ascorbic Acid Prevents Vascular Endothelial Dysfunction Induced by Electronic Hookah (Waterpipe) Vaping.
- In 10 healthy young adults, adding vitamin C to acetylcholine during 4-6 days at 4300 meters altitude raised the blood flow response in the forearm by about 20%, partly restoring the response that altitude had reduced by about 30%.GLOBAL REACH 2018: intra-arterial vitamin C improves endothelial-dependent vasodilatory function in humans at high altit…
- A review of epidemiologic and trial research found that vitamin C may slightly improve blood vessel function and blood fats in some groups, especially those with low vitamin C levels, but there is little support for supplementing to reduce heart disease risk.Vitamin C and Heart Health: A Review Based on Findings from Epidemiologic Studies.
- In people with nose and eye socket injuries, alpha-tocopherol acetate was given alongside other antioxidants and standard care, and the combination improved small blood vessel flow; vitamin E's effect could not be separated from the others.[Disorders of physiological parameters of the body (lipid peroxidation and microcirculation) after naso-orbital injuries…
Review Totals and Summary
Members OnlyWhat buyers say
No written reviews read yet.
Biohacker Summary
Members Only0 of 10 recommend it
0 of 10 biohackers on our panel recommend it
Vitamin C gets most of the panel's attention, and most of the ten recommend or use it, mainly for collagen and skin, joint and connective tissue support, and immune health. Several pair it with collagen, with one suggesting taking both about an hour before a workout. Doses people mention range from 250 milligrams to an extra gram a day, and one panelist cites 2 to 4 grams for inflammation, while another notes the best dose is unsettled and very high amounts might blunt some benefits of exercise. One panelist stopped using a vitamin C serum because of its smell and says applying it to the skin delivers far more than eating it, and another says extra vitamin C has not been shown to protect against cataracts. Vitamin E drew only a few comments, with one panelist recommending it and giving it to their kids daily, while biotin is a smaller ingredient in this product, and one panelist warns it can distort certain hormone blood tests.
See all 10 biohackers →Hide the biohackers
Ben Greenfield · Vitamin E · neutral
- Mentions a recent study showing no significant increase in bleeding for patients on Vitamin E supplementation during open heart surgery, which was interesting for him to learn.
- 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.
- 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.
- Notes a new study indicating that vitamin E is a core dietary antioxidant closely associated with a reduced risk of accelerated biological aging.
- Recommends Xtendlife's Tocotrienols Vitamin E for cardiovascular, brain, and healthy aging support, noting that research points to tocotrienols over alpha-tocopherol.
- 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.
- Recommends whole food vitamin E, explaining that typical supplements only provide alpha-tocopherol, while the whole food complex includes four tocopherols and four tocotrienols, often with selenium at the core.
- Warns against ascorbic acid, stating that it does not cure scurvy and that the world has been led astray by the deception around it versus the whole food vitamin C complex.
- Warns against taking 335 mg of vitamin E immediately after a workout for individuals under 50, as it can dull the body's natural adaptation signal.
- Warns against taking 1,000 mg of vitamin C immediately after a workout for individuals under 50, as it can dull the body's natural adaptation signal.
- Warns that using high-dose antioxidants like vitamin C directly before or after a hyperbaric session is not a great idea, as it could impair some of the effects by reducing reactive oxygen species.
Siim Land · Vitamin C · recommends
- 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.
- 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.
- Notes that oral vitamin E and C supplementation has been noted to increase the dose of UVB radiation from the sun needed to cause redness of the skin, suggesting increased resilience against sun damage. He also mentions a trial where a combination of slow-release vitamin C and vitamin E decreased the progression of carotid atherosclerosis in men.
- Mentions vitamin C in comparison to topical melatonin for oxidative defense, stating that melatonin would compete but is not as broadly validated clinically.
- Mentions vitamin E 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.
- 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.
Dr. Eric Berg · Vitamin C · neutral
- 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.
- Mentions that grass-fed liver has vitamin E.
- Highly recommends taking natural food vitamin C, about 500 mg, at the first sign of a cold.
- Dr. Berg states that synthetic vitamin E may be acceptable for short-term use, but long-term use can contribute to oxidative stress.
- Warns against synthetic vitamin E (dl-alpha-tocopherol) for ongoing maintenance, citing a trial where it increased prostate cancer risk and explaining that it can become a free radical and starve out necessary protective forms of vitamin E.
- States that thinning hair often indicates low biotin, which is required to produce keratin for hair, skin, and nails.
- Recommends consuming foods high in vitamin C to block the effects of grains.
- Recommends taking vitamin E to block the effects of grains.
- Recommends ensuring that collagen supplements come with vitamin C.
- Mentions that castor oil contains vitamin E, which is crucial for maintaining skin barrier function.
- Vitamin C works as an antioxidant that supports skin and artery health.
Thomas DeLauer · Vitamin C · recommends
- 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 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.
- Mentions a causal link found between vitamin E and waking up in the middle of the night.
- 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.
- Recommends using a multivitamin to ensure adequate micronutrient intake, especially when wholesome food is less available.
- Advises checking multivitamins because many contain 100, 200, or 300% of the daily value of selenium, which can contribute to excessive intake.
- Recommends vitamin E for protecting skin cell membranes, reducing oxidative stress, and preventing lipid damage, especially for those with high stress and low dietary intake.
Dave Asprey · Vitamin C · recommends
- Recommends taking vitamin C for better skin health.
- States that currently, he is only taking vitamin C and vitamin D.
- Dave Asprey's kids get a little bit of vitamin E every day, which helps to stabilize the bad oils they get when eating at restaurants.
- Recommends Vitamin E as one of the most important supplements for overall health.
- 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.
- Takes Vitamin DAKE from Suppgrade Labs because D3, A, K2, and E work together.
- Notes that plain Vitamin C isn't enough and that most people never think to check for a specific ingredient that makes it work.
- Includes vitamin K2 as a critical ingredient in Vitamin DAKE, stating that the body needs the right fat soluble vitamins for thousands of reactions.
- 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.
- 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.
- Mentions Vitamin DAKE from Suppgrade Labs as a product that combines fat-soluble vitamins D, A, K, and E to work together.
- States that Ensure is like SlimFast but worse, and that its ingredients, including synthetic vitamins, guar gum, maltodextrin, high fructose corn syrup, and seed oils, are disgusting and should not be given to sick or well people.
Dr. Mark Hyman · Vitamin C · recommends
- 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 patients who were very malnourished had extremely low vitamin E.
- Recommends vitamin C for immune system support and modulation.
- Relies on Big Bold Health's HTB Immune Energy Chews, which deliver 1000mg of sprouted Himalayan tardy buckwheat, along with vitamin C, D, magnesium, and zinc, to support immune balance, resilience, energy, and focus.
- Lists Vitamin E as important for cell protection and anti-aging.
- Recommends avoiding Vitamin E for at least a week before surgery because it can thin the blood.
- Notes that Vitamin E levels are low in Parkinson's patients.
Dr. Rhonda Patrick · Vitamin E · neutral
- Lutein and zeaxanthin can also be obtained from certain multivitamins.
- 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.
- Choosing a multivitamin that includes lutein and zeaxanthin ensures you get meaningful amounts every day.
- Notes that ~60% of Americans are low in vitamin E.
- 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.
- Suggests avoiding a multivitamin if it contains biotin before a testosterone blood test to prevent confounding results.
- Suggests avoiding a multivitamin if it contains biotin before a testosterone blood test to prevent confounding results.
- Advises avoiding biotin-containing supplements before a testosterone blood test as they can cross-detect with estrogens and confound 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.
- Multiple randomized controlled trials show older adults taking a standard multivitamin (like Centrum Silver) had measurable improvements in processing speed, cognition, and episodic memory.
Andrew Huberman · Vitamin E · uses
- Takes a multivitamin every day for longevity.
- Takes a multivitamin every day for longevity.
- Mentions biotin.
- Recommends AG1, a vitamin, mineral, and probiotic drink, and notes that for a limited time, a subscription comes with additional supplements.
- 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.
- Warns that high-dose supplementation of Vitamin E, when given to lung cancer patients, led to worse outcomes than control subjects, highlighting that it's not the same as ingesting it in food.
- 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.
- Recommends AG1 as the highest quality and most complete foundational nutritional supplement, containing vitamins, minerals, probiotics, prebiotics, and adaptogens to cover dietary gaps and support a demanding life.
- States that AG1 is the highest quality and most complete foundational nutritional supplement available, containing vitamins, minerals, probiotics, prebiotics, and adaptogens, and that he has been taking it daily since 2012, often twice a day, to bolster his energy, immune system, and gut microbiome.
- Huberman mentions that vitamin C seems to help with the absorption or utilization of collagen protein.
- Recommends Vitamin E as part of the AREDS2 supplementation for slowing the progression of dry macular degeneration.
Peter Attia · Vitamin C · stopped
- 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.
- Warns that biotin, found in many supplements, can completely obscure findings and render a non-LCMS test for estradiol and testosterone irrelevant due to interference with ELISA-based assays.
- 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.
- Notes that there are some downsides to Vitamin E, including cardiovascular longitudinal risk and prostate cancer, and that discussions are needed with patients, especially those with diabetes or cirrhosis, due to studies indicating increased all-cause mortality depending on the dose.
- Advises that if taking a biotin supplement, one should discontinue it for at least a few days, if not a week, before a blood test, as it can dramatically skew thyroid values.
- Warns that certain things, like biotin, should not be taken before a blood test because they can mess up readings.
- Peter Attia, involved in the American Urological Association Peyronie's guidelines, stated that vitamin E is not indicated for Peyronie's disease and should not be given.
- States that American Urological Association guidelines advise against giving vitamin E for Peyronie's disease as it is not indicated.
- Notes that while vitamin C deficiency is associated with an elevated risk of cataract, supplementation to supranormal levels has been conclusively shown not to protect against cataract formation.
- Mentions that a survey of doctors showed they recommend Vitamin C for COVID-19, but notes there is no real evidence behind it.
- Expresses skepticism about 'panacea treatments' for cancer, specifically mentioning a 'twenty thousand dollars of vitamin C' treatment, implying it's an example of something he's 'squirrely' about due to cost and unproven claims.
- Asks if vitamin C matters for immune function, suggesting a need for a definitive study.
Bryan Johnson · Vitamin C · neutral
- 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.
- Mentions biotin as an example of an ingredient that AG1 lists with a specific dose, but then contrasts it with other ingredients in proprietary blends where doses are not disclosed.
- Takes 250 milligrams of Vitamin C.
- 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 adequate Biotin (Vitamin B7) for hair health, noting it is in the Blueprint stack.
- Recommends adequate Vitamin E for hair health, noting it is in the Blueprint stack.
- Uses Vitamin E at 10 IU/ML in his custom topical hair formulation.
RAL Summary
Members OnlyTier 4 for Circulation
Vitamin C and vitamin E are only trace amounts compared with the doses that helped blood vessels in studies. The one biotin study found no blood flow benefit [7]. No reviews were counted, so the evidence stays thin at tier 4.
- Emerging: not enough evidence to rank higher yet.
- Vitamin C: trace amount
- Vitamin E: trace amount
Where the evidence disagrees: 12 of the 68 human studies found no effect.
More Details
Members OnlyBody systems · Combine with · Possible side effects
Body systems: Cardiovascular system, Skin and hair
Possible side effects: No major side effects reported.
Supplement Facts
Includes 0 g Added Sugars 0 g · Sugar Alcohol 3 g · Vitamin C 15 mg
Supplement Facts
Serving Size 2 Gummies
Servings Per Container 60
Amount Per Serving% Daily Value
| Calories | 10 | |
| Total Carbohydrate | 3 g | |
| Total Sugars | 0 g | |
| Includes 0 g Added Sugars | 0 g | |
| Sugar Alcohol | 3 g | |
| Vitamin C | 15 mg | |
| Vitamin E | 6.8 mg | |
| Biotin | 2,500 mcg | |
| Sodium | 15 mg |
Other ingredients: Maltitol Syrup, Isomalt, Maltodextrin, Xylitol, Pectin, Less than 2% of Carnauba Wax, Citric Acid, Fractionated Coconut Oil, Natural Flavors, Color Added, Sodium Citrate. Maltodextrin adds a trivial amount of sugar.
Directions: Adults, chew 2 gummies daily. Keep out of reach of children. Store tightly closed, in a cool, dry place. Contents may settle over time.
Barcode (UPC) 031604006006 · Label source: Reverseagelab · Report a label change
Show entire label
More circulation products
Members OnlyThe highest ranked for the same goal
Read more
Our articles on this subject
- Supplements for Focus and Mental ClarityArticle · Jun 16, 2026
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.
Privacy policyConsumer health dataAffiliate disclosureTermsDo Not Sell or Share My Personal InformationCookie settings