NOW Calcium & Magnesium Citrate Powder with Vitamin D3 Review
NOW Calcium & Magnesium Citrate Powder with Vitamin D3 is presented as an optimal bone structure support formula designed by NOW's certified nutritionists. The product is described as containing key nutrients that play essential roles in bone metabolism. The page states that the citrate forms of calcium and magnesium are highly absorbable and support strong bones and teeth as well as muscle and nerve function. Vitamin D3 is included to complement calcium and magnesium and its role in maintaining mineral homeostasis and bone structure. Listed highlights are Citrate Powder with Vitamin D3, a 1:1 Mineral Ratio, and Enhanced Mixability. The product color is listed as off white, and the page notes that natural color variation may occur and that the product is sold by weight, not volume. The size is 8 oz. with 50 servings listed in the size table and about 45 servings per container on the Supplement Facts panel. The serving size is 1 1/2 level teaspoons (approx. 5 g) providing 400 mg elemental calcium from calcium citrate, 400 mg elemental magnesium from magnesium citrate, and 5 mcg (200 IU) vitamin D3 as cholecalciferol. Suggested use is to mix 1 1/2 level teaspoons into at least 8 oz. of cold water or clear liquid until fully dissolved, which may then be added to smoothies or juices, taken once daily with a meal. The page warns that pure calcium and magnesium citrate powders can increase the temperature of liquids on contact, so the serving must be mixed into cold liquid before ingestion. Caution notes say the product is for adults only, should not be breathed in, should be kept away from skin and eyes, and should be kept out of reach of children. Consult a physician if pregnant, nursing, taking medication, or having a medical condition. The product is listed as Kosher (Triangle K), Non-GMO, and Intertek GMP Supplement Certified, and is made without dairy, eggs, nuts, gluten, or soy. The page states it is made and quality tested in the USA with globally sourced ingredients and that the company has been family owned since 1968. The bottle is noted as made from 100% post-consumer recycled resin. The page also includes the standard statement that these statements have not been evaluated by the Food and Drug Administration.
Study, Trial or Testing Result Summary
Members Only25 human studies · 7 improved
The human evidence for this product's ingredients and bone health is mixed. Calcium plus vitamin D slightly improved pelvic bone density in a review of 11 trials with 43,869 women with thinning bones after menopause, but not spine or hip density, and did not reduce fractures [1]. For vitamin D, 700 to 800 international units a day cut hip fractures by 26% in older adults, while 400 units did not help [2]. Another review of nine studies found no clear drop in fractures [3], and a review of women without thinning bones could not confirm fewer fractures [4]. Calcium trials using 1 gram or 1200 milligrams a day, more than the 400 milligrams in one serving, showed no clear gain over placebo or simply kept bone stable [5][6]. Surveys tie higher dietary calcium to denser bones, in one case only in women [7][8], but a six-year study found no link to bone loss [9]. Magnesium has no human studies here; the only support comes from magnesium implants placed in animal bones, not supplements [10][11]. Animal and cell studies are never counted.
See all 25 studies →Hide the studies
- In 11 trials of 43,869 postmenopausal women with osteoporosis, calcium plus vitamin D modestly improved pelvic bone density but not spine, neck of femur or total hip density, and did not reduce fractures.The effects of combined calcium and vitamin D supplementation on bone mineral density and fracture risk in postmenopausa…
- This review of smartphone apps for osteoporosis self-management did not test vitamin D supplements and found no significant effect on vitamin D intake.Digital Health Technologies for Long-term Self-management of Osteoporosis: Systematic Review and Meta-analysis.
- In trials of older adults, 700 to 800 IU a day of vitamin D cut hip fracture risk by 26% and other nonvertebral fractures by 23%, while 400 IU a day gave no significant benefit.Fracture prevention with vitamin D supplementation: a meta-analysis of randomized controlled trials.
- Across nine studies, vitamin D3 did not significantly reduce nonvertebral or vertebral fractures versus placebo or calcium alone, with only a borderline trend toward fewer falls.The effect of cholecalciferol (vitamin D3) on the risk of fall and fracture: a meta-analysis.
- In 23 trials of 1,209 kidney transplant recipients, vitamin D analogues (2 trials, 51 patients) improved lumbar spine and femoral neck bone density versus no treatment, but no trial showed fewer fractures.Interventions for preventing bone disease in kidney transplant recipients: a systematic review of randomized controlled …
- In 18 small trials of 576 children with chronic kidney disease, vitamin D preparations lowered parathyroid hormone levels, but there were few data on growth or bone deformities and no clear differences between preparations.Interventions for metabolic bone disease in children with chronic kidney disease.
- One small trial of 39 people with sickle cell disease found vitamin D3 for six weeks raised blood vitamin D and reduced pain days versus placebo, but no bone outcomes were reported and the evidence was low quality.Vitamin D supplementation for sickle cell disease.
- In nine trials of postmenopausal women without osteoporosis, vitamin D raised blood vitamin D and improved some bone remodeling measures, but only one study found fewer fractures, so a fracture benefit could not be confirmed.Supplementation of vitamin D isolated or calcium-associated with bone remodeling and fracture risk in postmenopausal wom…
- In a review of 25 observational studies of healthy men aged 50 or older, evidence linking calcium intake to bone density or bone loss was inconsistent or weak.Risk factors for low BMD in healthy men age 50 years or older: a systematic review.
- In 500 elderly women with Alzheimer disease who all took 1000 IU of vitamin D2 plus calcium, adding risedronate for 18 months raised bone density 4.1% and cut hip fracture risk compared with placebo, but vitamin D itself was not tested alone and the paper was retracted.The prevention of hip fracture with risedronate and ergocalciferol plus calcium supplementation in elderly women with Al…
- Children whose mothers took 1000 IU of vitamin D3 daily during pregnancy had higher whole-body bone mineral content and density at ages 6-7 than children whose mothers took placebo.Pregnancy vitamin D supplementation and offspring bone mineral density in childhood follow-up of a randomized controlled…
- In 242 elderly men with Parkinson disease who all took 1000 IU of vitamin D2, adding risedronate for 2 years raised bone density, but vitamin D was not compared against placebo and the paper was retracted.Risedronate and ergocalciferol prevent hip fracture in elderly men with Parkinson disease.
- In 39 older women with severe osteoporosis, 1200 mg of calcium daily with or without 25-hydroxyvitamin D for two years kept bone mineral content stable in both groups, with improved bone mineralization rate in both groups.Histomorphometric effects of calcium or calcium plus 25-hydroxyvitamin D3 therapy in senile osteoporosis.
- In 40 postmenopausal women with wrist fracture, 1 g of calcium daily for one year had no significant effect on femur bone mineral content compared with placebo.Bone mineral content in women with Colles' fracture: effect of calcium supplementation.
- In 2904 US adults aged 60 and over, higher dietary calcium was linked with higher lumbar bone density, but this link held in women and not in men.Association between Dietary Calcium Intake and Bone Mineral Density in Older Adults.
- In 1479 elderly Japanese men, greater milk intake was linked with higher hip and femoral neck bone density and lower bone turnover, though this link weakened after accounting for calcium intake.Greater milk intake is associated with lower bone turnover, higher bone density, and higher bone microarchitecture index…
- In 1098 adults aged 65 and over, higher dietary calcium intake was linked with higher bone density at the hip and spine, while higher urinary sodium was linked with lower bone density.Dietary intake, blood pressure and osteoporosis.
- In 698 placebo-group women over 65 with osteopenia, averaging 886 mg of dietary calcium a day over 6 years, calcium intake was unrelated to bone loss at any site.Dietary Calcium Intake and Bone Loss Over 6 Years in Osteopenic Postmenopausal Women.
- In a survey of 452 women in Alaska, dietary calcium intake was low (about 306 mg a day on average), but the survey did not test calcium supplements, so it shows no effect of calcium on bone.Risk factors for osteoporosis in Alaska Native women: a cross-sectional survey.
- In Tuscany, Italy, most people who broke a hip from 2011 to 2015 were not taking vitamin D supplements, and only 30-35% were on cholecalciferol one year after the fracture; no bone outcome was measured against a comparison group.The use of cholecalciferol in patients with hip fracture.
- Among 173 adults aged 35 to 50, about a quarter had osteopenia; bone density correlated with exercise in women and in the opposite direction in men, and no calcium-specific result was reported.Bone Mineral Density Among Men and Women Aged 35 to 50 Years.
- In a 2-year cross-sectional study of 116 pre- and post-menopausal obese and non-obese women, daily vitamin D and calcium intake was low and osteoporosis was less common in obese women, though blood vitamin D levels were within normal range.Dietary Pattern and Bone Health in Pre and Post-menopausal Obese Women.
- In 52 Parkinson's patients compared with 52 matched controls, lower bone density was seen, and insufficient calcium intake was among the factors related to low bone density.Prevalence and risk factors of osteoporosis in patients with Parkinson's disease.
- In 70 people taking meds, a dedicated bone clinic found many with bone loss; early results showed bone density rose 3 to 5 percent with drug and lifestyle measures, including calcium and/or vitamin D in 44 people.Read the study on PubMed (10678299) →
- In 42 Iranian adults with hemophilia, low bone density was very common, and only cigarette smoking was significantly linked to it, not calcium intake.Bone mineral density in hemophilia patients.
Review Totals and Summary
Members Only3,764 reviews · 90% positive
Customers generally view NOW Calcium & Magnesium Citrate Powder with Vitamin D3 positively, with 71% of its approximately 3331 ratings across various stores giving it 4 or 5 stars. This summary focuses exclusively on feedback for the powder form of the product, excluding comments about other forms like capsules or gummies. **Overall Effectiveness and Benefits** Many buyers report positive health outcomes from using this powder. It is frequently mentioned for supporting bones and helping with sleep and muscle cramps, with some users noting they "feel more relaxed and balanced overall," especially at night. Some reviewers use it to balance their calcium intake, particularly those who consume dairy, as the powder "balances out dairy calcium which has very little magnesium." Vegans find it helpful to meet calcium and magnesium needs that plant-based foods alone may not provide, with one saying, "do not get all the calcium I need from the plants foods." The product also suits individuals with filler allergies, with one reviewer stating it "works really well for me." Beyond human consumption, one unique application mentioned is for insect gut-loading, where it "corrects the Ca:P ratio from a deficiency." Some users also report feeling more energized. **Taste, Texture, and Mixability** The powder form is generally appreciated for its versatility. Many customers find it "dissolves nicely in liquids" and "mixes easily via spoon or shaking" into various beverages like plant milk, tea, warm water, juice, whey protein drinks, kefir, yogurt, and cottage cheese. Some even say it makes drinks "taste, feel, and look more like milk." However, taste and texture are also common points of criticism. Some reviewers describe the taste as "Tastes bad," "terrible," or "unpleasant, sour or gritty," especially with plain water. Others find it gritty or note that it "doesn't dissolve well" in plain water. A few users, however, describe the taste as mild. **Value and Convenience** The product is often praised for its affordability and longevity. Customers describe it as "priced very well" and say it "does not break the bank." The bottle is noted to "last you too," offering good value for the amount of calcium and magnesium provided. The powder form also allows for flexible dosing, giving users "more choice on how many milligrams you need." Many find it "So much easier than pills" to consume. Packaging received mixed feedback; while some describe it as well-designed, a common practical complaint is that the tall bottle makes it "hard to get a measuring spoon down to the bottom," and some wish it came with a measuring spoon. Fast shipping and good packaging from sellers were also noted. **Specific Suitability and Considerations** This supplement appears well-suited for vegans, individuals looking to balance calcium intake from dairy, and those with allergies to common supplement fillers. It is also a good option for people who prefer not to take pills. While generally well-tolerated, a few users experienced mild nausea when first starting, which they resolved by halving the dose. One reviewer mentioned a doctor advised them to switch products for a child, which was a neutral experience rather than a complaint about the product's quality. Warnings about potential magnesium overdose and caution for people with chronic kidney disease are also mentioned in store summaries.
Biohacker Summary
Members Only8 of 10 recommend it
Vitamin D is the main ingredient, and all ten panelists spoke about it: most recommend or use it, and a few stayed neutral. Reasons given include immune support, muscle and brain health, mood, and general health, with several saying to get blood levels tested and aim for levels in the 40 to 100 range. Doses mentioned run from 5000 IU of D3 in the morning, taken by two of them, up to at least 10,000 IU daily in winter, and one takes it in fall and winter when sun is scarce. They suggest taking it with dietary fat or a meal for better absorption, one warns that the standard recommended intake is too low, and another says supplementing makes little sense unless you are deficient. Magnesium is a smaller ingredient in this product, and the panel mostly takes it for sleep.
See all 10 biohackers →Hide the biohackers
Dr. Eric Berg · Vitamin D · warns
- Dr. Berg warns that the recommended daily intake for vitamin D is based on a massive error and that the actual necessary amount is closer to 8,895 IU, with millions remaining deficient.
- Recommends getting vitamin D levels tested to ensure they are between 50 and 70, as vitamin D is intimately involved in regulating prostate size.
- Recommends taking at least 10,000 IUs of vitamin D3 every single day in the winter, stating it is the most important vitamin to lower cancer risk.
- Recommends vitamin D to support the immune system, aiming for blood levels between 80 to 100 ng per ml.
- Dr. Eric Berg states that magnesium supports energy, muscle function, and sleep, and that most of it is stored inside cells, making deficiencies harder to detect with a standard blood test.
- Notes that magnesium could also be a factor in preventing muscle cramps.
- Recommends taking no less than 10,000 IU's of vitamin D3 for osteoporosis, alongside magnesium and K2.
- Recommends increasing vitamin D to restore balance and support healthy blood pressure.
- Recommends magnesium, specifically magnesium glycinate, stating it is key for D3 and K2 to work and is probably more important than calcium for building bone.
- Recommends increasing magnesium to restore balance and support healthy blood pressure.
- Warns that bone loss cannot be fixed with just calcium, as bone is primarily collagen with other essential minerals.
- States that a lack of vitamin D can potentially cause achy bones or crashing mood.
- Dr. Eric Berg suggests that magnesium could help support deeper, more restful sleep.
- Recommends Magnesium Glycinate, noting that the combination of magnesium and glycine is helpful for connective tissue, sleep, and reducing stress.
Dave Asprey · Vitamin D · uses
- Takes Vitamin DAKE from Suppgrade Labs.
- Mentions magnesium in the context of sleep but states that it doesn't address the core issue of waking up during the night.
- Suggests that vitamin D supports brain health, muscle function, and focus.
- Suggests that magnesium may help slow aging, support cellular repair, and improve sleep.
- States that magnesium can affect how the body responds to a supplement.
- Host Dave Asprey explains why correcting a vitamin D deficiency still makes sense for male fertility, even though supplementation did not improve overall semen parameters in a randomized trial.
- States that currently, he is only taking vitamin C and vitamin D.
- Recommends fixing sleep with 300mg of Magnesium 101 before bed if diet and exercise aren't melting stubborn belly fat.
- Dave Asprey says his daily routine includes magnesium as part of a carefully developed combination for longevity.
- Recommends vitamin D, noting it's actually a hormone and that most people are deficient, even those who take it, because they don't take enough.
- Recommends magnesium glycinate for sleep, stating that trials show it helps people fall asleep about 17 minutes faster and that he finds it incredibly effective.
- States that most people on the spectrum are low in vitamin D and need more of it, mentioning his own product, Vitam DAKNE, which contains real vitamin A.
- Mentions magnesium glycinate as one of the five gut-friendly, extensively researched ingredients in Kill Switch that helps with natural sleep.
- Dave Asprey recommends Vitamin D3 with K2, explaining D3 is a hormone made from sunlight and K2 directs calcium into bones, not arteries, highlighting its low cost, widespread deficiency, and the ability to test its effectiveness.
Siim Land · Vitamin D · recommends
- Advises against taking vitamin D in the morning with other supplements because it is fat soluble and requires dietary fat for better absorption.
- Recommends taking Vitamin D with fat for better absorption.
- States that Magnesium can be a useful addition for some people for sleep.
- States that Vitamin D connects biology to light and that UVB reaching the skin enables its production.
- Recommends magnesium for sleep, especially deep sleep, and suggests trying better types like Threonate, Biscinate, or Torate, referencing a study where magnesium supplementation improved deep sleep.
- Recommends Magnesium for blood pressure, migraines and deficiency, based primarily on human research, especially randomized controlled trials showing measurable benefits.
- Lists Magnesium as one of 15 supplements backed by human studies.
- States that magnesium is a fundamental mineral governing over 600 enzymes and metabolic reactions, and recommends that most people need at least 400-500 mg/d for health, with some needing up to 600 mg/d.
- Lists seafood and pumpkin seeds as sources of Magnesium.
- Lists dairy and sardines as sources of Calcium.
- Thinks vitamin D has some of the strongest evidence and is worth considering.
- Notes that Vitamin K2 pairs well with vitamin D by regulating calcium and bone mineralization.
- Thinks magnesium has some of the strongest evidence and is worth considering.
- Recommends taking vitamin D supplements with some fat to maximize its absorption, suggesting with food or a teaspoon of olive oil.
Ben Greenfield · Vitamin D · recommends
- Notes that Vitamin D is actually a hormone and recommends patients aim for levels around 40 to 50, or even 60 for fracture healing, for optimal healing, as opposed to just above 20 which is considered normal.
- Uses magnesium during surgery because it is neuroprotective.
- Says he is drinking LMNT, which contains sodium, potassium, and magnesium, and states that he actually drinks this stuff.
- Mentions vitamin D as part of a bare-minimum protocol.
- Advises getting vitamin D levels between 60 and 100 nanograms per milliliter as a minimum step for overall health and to slow down heart disease.
- Mentions magnesium as part of a bare-minimum protocol.
- Advises getting red blood cell magnesium levels to the high end of the range as a minimum step for overall health and to slow down heart disease.
- Recommends supplementing with magnesium threonate if one is low in magnesium, as it crosses the blood-brain barrier and is demonstrated to increase hippocampus plasticity, theoretically making one smarter and improving memories.
- Uses Magnesium Breakthrough from BIOptimizers as part of their daily stack, taking four capsules in the evening to support relaxation, recovery, and a good night of sleep.
- Has been taking Vitamin D3 K2 for over a decade.
- Recommends Celtic Sea Salt's new electrolyte drink "Hydrate" for replacing electrolytes and trace minerals lost through sweat, noting it contains 70 naturally occurring trace minerals, plus magnesium, taurine, and potassium.
- Had heart palpitations when he was really overdoing magnesium, not knowing what he was taking.
- Notes that sunlight influences more than just vitamin D production.
- Recommends keeping vitamin D levels high, suggesting that a supplement is probably not a bad idea, especially given that many people are deficient due to spending most of their time indoors.
Dr. Mark Hyman · Vitamin D · recommends
- Recommends Vitamin D for health, stating that amazing things happen when patients' vitamin D statuses reach optimal levels.
- Recommends considering magnesium glycinate before bed for nervous system support, deeper sleep quality, and to help the body transition into rest, and states that they take it every night.
- Mentions vitamin D as an existing biomarker that plays a role in mental health, which Function Health includes in their measurements.
- Recommends Magnesium Breakthrough Advanced 10 from Bioptimizers for restful sleep, muscle recovery, stress resilience, and metabolic health, especially during stressful times of the year.
- Notes that vitamin D plays a role in immune function.
- Recommends magnesium because it is involved in over 600 reactions in the body and up to 80% of people may have low levels that never get flagged on a standard blood test.
- Recommends magnesium as a basic supplement during detoxification to support pathways, help with constipation, and provide electrolytes.
- Recommends checking vitamin D levels and states that if they had to pick one single intervention for immune health, vitamin D would be it.
- Dr. Hyman discusses vitamin D in relation to sun exposure patterns.
- States that vitamin D supplementation can help with oxidative stress.
- Recommends Magnesium Breakthrough Advanced 10 from Biooptimizers, which contains 10 bioavailable forms and 550 mg of elemental magnesium, to support restful sleep, restorative sleep, muscle recovery, stress resilience, and metabolic health.
- Mentions vitamin D as a key nutrient for supporting immune function.
- States that vitamin D is probably the single most important intervention for immune health, recommending levels of 45 to 70 and emphasizing testing to determine the right dose.
- Notes that rickets, which causes terrible bone deformities, is caused by vitamin D deficiency.
Thomas DeLauer · Vitamin D · uses
- Uses vitamin D3 in the fall and winter months when getting less sun, as it's important to supplement it then.
- Uses Element's cans which contain 30 milligram magnesium, finding that electrolytes help his workout performance.
- Uses Element's 30 mg magnesium cans first thing in the morning to prime his day and help with workout performance.
- Recommends magnesium around the time one would normally break a fast to calm the brain and dull feelings of conditioned hunger.
- Recommends taking a massive amount of vitamin D simultaneously with an early morning massive breakfast to help reset circadian rhythms and address hyperphagia.
- Recommends Vitamin D, stating that it has receptors throughout the brain and deficiency can quickly impact brain and mood.
- Recommends magnesium, noting it is a cofactor for enzymes that build neurotransmitters, and deficiency can affect mood, happiness, and motivation.
- Takes supplemental vitamin D because he is skin sensitive and from northern latitudes, limiting his UV exposure.
- Notes that modern agricultural practices have led to soils depleted of trace minerals like magnesium, resulting in widespread magnesium deficiency.
- Recommends taking vitamin D on non-liver days to ensure both nutrients get proper receptor access.
- Recommends taking some magnesium glycinate tonight to help calm down and sleep.
- Takes Purity's liquid vitamin D3 with K2 because she is constantly inside during the day; D3 is for overall wellness and K2 helps the body absorb calcium properly.
- Mentions that magnesium in pumpkin seeds relaxes bronchial smooth muscle.
- Compares magnesium content, stating bananas have 32mg and pumpkin seeds have 156mg per ounce, a 5x difference.
Bryan Johnson · Vitamin D · uses
- Takes 5000 IU of Vitamin D3 in the morning for general health.
- Takes 400 mg of Magnesium Threonate before bed for sleep.
- Takes 5000 IU of Vitamin D3 in the morning for general health.
- Takes 400 mg of Magnesium L-Threonate before bed for sleep.
- Mentions that the sunlight assessment claims low vitamin D levels cause the immune system to misfire, and notes that their vitamin D has been measured.
- Takes 5000 IU of Vitamin D3 in the morning for longevity.
- Takes 400 mg of Magnesium Threonate before bed for sleep.
- He takes 5000 IU of Vitamin D3 in the morning for general health.
- He takes 400 mg of Double Wood Magnesium L-Threonate before bed for sleep.
- Takes 5000 IU of Vitamin D3 in the morning for general health.
- Takes 400 mg of Magnesium L-Threonate before bed for sleep.
- Takes 5,000 IU of Vitamin D3 in the morning for longevity.
- Takes 400 mg of Magnesium Threonate before bed for sleep.
- Takes 5,000 IU of Vitamin D3 in the morning.
Dr. Rhonda Patrick · Vitamin D · neutral
- Vitamin D supplementation was linked to a 40% lower risk of dementia in an observational study of more than 12,000 older adults.
- Magnesium supplementation has lowered blood pressure in randomized controlled trials. An analysis of 34 trials involving over 2,000 participants found modest reductions in both systolic and diastolic pressure, with a median dose of 368 mg/day.
- Warns that some magnesium supplements make the dose look much larger than it really is and that labels can fool people.
- Mentions that vitamin D also plays a role in maintaining muscle mass.
- Mentions magnesium as an important nutrient component for testosterone.
- Recommends ensuring adequate vitamin D intake for men's sperm health.
- Warns that some supplement companies mislead consumers by listing the total compound weight of magnesium citrate as the elemental magnesium dose, when the actual elemental magnesium content is much lower, potentially around 44-66 milligrams.
- Vitamin D and strength training alone did not, but adding them strengthened the effect on one clock, with the full combination slowing that measure by ~3.8 months.
- States there is not yet strong, consistent evidence that magnesium supplementation reliably improves sleep, noting that while some meta-analyses suggest it can improve sleep quality scores, sleep efficiency, and sleep duration, individual studies are inconsistent and several have found no meaningful effect.
- Lutein and zeaxanthin can also be obtained from certain multivitamins.
- States that magnesium may help modestly lower blood pressure by playing an important role in regulating vascular tone and influencing calcium signaling, with studies showing a reduction in systolic and diastolic blood pressure by 2 mmHg at a dose of around 370 mg/day for about 3 months.
- Recommends considering magnesium to improve mood.
- Recommends Vitamin D, noting it regulates over 5% of the genome, including genes involved in immune defense, neurotransmitter synthesis, and longevity, and correcting deficiency may slow epigenetic aging.
- Recommends Magnesium, stating that roughly half of Americans don’t get enough and it is a cofactor for over 300 biological processes, including DNA repair and energy production.
Andrew Huberman · Vitamin D · neutral
- Notes that most people are probably deficient in vitamin D and benefit from supplementing, but there's no point in doing it unless you're deficient for most things.
- Discusses Magnesium Threonate as a tool for falling asleep.
- Takes 5,000 IU of Vitamin D3 in the morning for longevity.
- Takes 400 mg of Magnesium Threonate before bed for sleep.
- Uses Element, an electrolyte drink with sodium, magnesium, and potassium in correct ratios and no sugar, to ensure adequate hydration and electrolytes, especially when starting days fast or during physical exercise.
- Takes 5000 IU of Vitamin D3 in the morning for general health.
- States that Vitamin D is one of the critical nutrients with the best evidence for cognitive function and reducing the risk of dementia.
- Takes 400 mg of Magnesium L-Threonate before bed for sleep.
- Confirms that magnesium is absolutely important for cognitive function, noting studies show those with lower magnesium intakes tend to perform less well on cognitive function tests, and it's related to brain changes over time and dementia risk.
- Takes 5000 IU of Vitamin D3 in the morning.
- Takes 400 mg of Double Wood Magnesium L-Threonate before bed for sleep.
- He takes 5,000 IU of Vitamin D3 in the morning for overall health.
- He takes 400 mg of Magnesium L-Threonate from Double Wood before bed for sleep.
- Takes 5000 IU of Vitamin D3 in the morning.
Peter Attia · Vitamin D · uses
- Lists vitamin D as one of her staple supplements.
- Peter reviews the evidence for select off-label medications and supplements commonly used for sleep, including glycine, magnesium, ashwagandha, and phosphatidylserine.
- Suggests that zinc and magnesium could potentially help with vasodilation and sleep, particularly for women experiencing severe symptoms in the luteal phase.
- Notes that several studies show patients taking vitamin D can reduce TPO levels and prolong the honeymoon period of Hashimoto's disease.
- Peter discusses electrolytes and fiber and the ketogenic diet, specifically preventing magnesium loss.
- States that in mouse studies, there was a combined effect of alpha ketoglutarate with vitamin D for both sexes.
- Uses vitamin D as an example of how people might dismiss its efficacy due to failed clinical trials that didn't adjust the dose or measure levels.
- In mouse studies, Peter Attia's team found a combined effect of AKG with Vitamin D for both sexes.
- Suggests that supplementing with lots of vitamin D might help overcome the negative effects of phenytoin on bone health by improving calcium absorption, though he is unaware of studies on this.
- Recommends Vitamin D3 as one of the 'big three' micronutrients for bone health, suggesting a daily intake of 800 to 1,000 IU, which can be obtained through sunlight or supplementation.
- Recommends magnesium as one of the 'big three' micronutrients for bone health, suggesting a daily intake of 300 to 500 milligrams as a minimum, and personally aims for about a gram of supplemental magnesium.
- Recommends calcium as one of the 'big three' micronutrients for bone health, suggesting a daily intake of 1,000 to 1,200 milligrams, which can be supplemented with calcium carbonate or calcium citrate.
- Suggests that supplementing with lots of vitamin D might overcome the negative effects of phenytoin on bone health by counteracting increased catabolism of vitamin D and subsequent decreased calcium absorption.
- Recommends magnesium for optimizing bone mineral density, suggesting a daily intake of 300 to 500 milligrams as a minimum, but personally aims for about a gram.
RAL Summary
Members OnlyTier 4 for Bone Health
The second tier rests on a survey linking dietary calcium with bone density in 2,904 adults, which was observational and held only in women, while the controlled trials of calcium and vitamin D are mixed and show no fewer fractures, so the evidence is mixed rather than a clear improvement. So it is graded Tier 4, lower than the rules alone gave.
- Emerging: not enough evidence to rank higher yet.
Where the evidence disagrees: 9 of the 25 human studies found no effect.
More Details
Members OnlyBody systems · Combine with · Possible side effects
Body systems: Skeletal system, Muscular system, Digestive system
Combine with: To enhance the benefits of Calcium, Magnesium, and Vitamin D3, consider combining this supplement with Vitamin K2, particularly MK-7. Vitamin K2 works synergistically with Vitamin D3 to ensure calcium is properly utilized and directed to the bones and teeth, rather than accumulating in soft tissues like arteries. Additionally, Boron can be a beneficial co-factor, as it plays a role in calcium and magnesium metabolism and can support vitamin D activity.
Possible side effects: A few reviewers had mild nausea when starting, eased by halving the dose, and some found the taste sour or gritty; the magnesium is above the daily recommended limit, and store notes advise caution for people with chronic kidney disease.
Supplement Facts
Vitamin D3 5 mcg · Calcium 400 mg · Magnesium 400 mg
| Vitamin D3 | 5 mcg | |
| Calcium | 400 mg | |
| Magnesium | 400 mg |
Directions: Suggested Usage: Mix 1 1/2 level teaspoons of powder into at least 8 oz. of cold water or clear liquid. Add powder slowly while stirring. Take once daily with a meal. Pure calcium and magnesium citrate powders can increase the temperature of liquids upon contact; therefore, the recommended serving must be mixed into at least 8 oz. of cold liquid to neutralize this reaction prior to ingestion.
Barcode (UPC) 733739012432 · Label source: NIH label database · Report a label change
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Graded November 3, 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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