Rexall Biotin 1000 mcg Review
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Study, Trial or Testing Result Summary
Members OnlyHuman studies
This product supplies a single ingredient, biotin, at 1000 micrograms per serving. For the goal of reversing aging or supporting cellular and DNA repair, no human studies on biotin were found, so there is no study evidence that it helps or fails for this goal. The research notes a reference amount of 2000 micrograms a day, but the basis for that figure is unclear. One serving of this product gives half of that amount. Without human trials, nothing can be said about whether biotin slows aging, repairs DNA, or changes aging markers. Customer feedback is very limited. Five ratings were counted, four out of five of them positive, but no written reviews could be read, so it is not known what buyers noticed or why they rated it as they did. No expert or biohacker statements were available. Taken together, this is an unproven option for this goal. Anyone choosing it for anti-aging purposes should know that the claim rests on no human study evidence and very few customer ratings. Animal and cell studies are never counted.
Review Totals and Summary
Members Only5 reviews · 80% positive
Extensive customer reviews and qualitative feedback are currently being aggregated for this product. Check back soon for a detailed sentiment analysis.
Biohacker Summary
Members Only0 of 10 recommend it
The panel is split on biotin, though it leans toward cautious use. Its main appeal is hair, skin and nails: several panelists recommend or use it for those reasons, and a few also tie it to blood sugar and insulin resistance. Four of the ten warn about it, mainly because it can throw off blood tests for hormones and thyroid, so they advise stopping it for a few days to a week beforehand, while others call it overhyped and say enough protein or food sources like eggs, almonds, salmon and organ meats may matter more. One panelist takes it about twice a week, another says it will not fix hair loss on its own, and no one gave a specific dose or a preferred form. None said they stopped taking it, and none named a supplement to pair it with.
See all 10 biohackers →Hide the biohackers
Dave Asprey · Biotin · warns
- Mentions that most places put in extra biotin for hair growth, suggesting it's not always necessary or beneficial.
- States that biotin clears out oxalates.
- Lists biotin as an important nutrient for hair health.
- Warns against taking biotin for a substantial period of time before lab testing, especially expensive immune stuff, because it will make results insane and doctors will think you're dying.
- Takes more biotin than others' genetics probably need.
- Takes excessive amounts of biotin due to his genetics, but warns that others may not need the same amount.
- Takes a substantial amount of biotin, believing it helps with oxalate removal, and noticed oxalate detoxing issues like deep pimples when increasing his dose.
- Warns that more people will be harmed by 20 milligrams of biotin a day than will be helped, and he himself developed significant neurological problems from taking 10 milligrams of biotin a day for five weeks.
- Dave's guest mentions that people looking to support their hair often turn to biotin.
- Dave personally takes 20-30 milligrams of biotin, initially for hair growth, and found that after an initial period of 'deep skin things' (dumping symptoms), he now does well on this dose, suggesting it helps with oxalate issues.
Dr. Eric Berg · Biotin · neutral
- States that thinning hair often indicates low biotin, which is required to produce keratin for hair, skin, and nails.
- Notes that fungus on nails, identifiable by yellowish discoloration, is an indication of low biotin due to an imbalance in the gut.
- Dr. Berg mentions that fermented dairy contains vital nutrients, including biotin.
- Dr. Eric Berg recommends biotin as a home remedy to help prevent hair loss and regrow hair.
- Mentions that fermented dairy provides vital nutrients such as biotin.
- Emphasizes that biotin is a vital cofactor for collagen absorption and function.
- States that brittle nails are usually caused by a biotin deficiency.
- Recommends getting biotin from a food source rather than a supplement for hair growth.
- Recommends biotin for hair growth, stating it is necessary to make keratin, which improves the hair shaft, makes it strong, and prevents thinning, fragility, and breakage.
- Suggests increasing biotin with a supplement if one has a biotin deficiency.
Thomas DeLauer · Biotin · warns
- Thinks biotin is a little overhyped, suggesting that consuming adequate protein is probably more effective for hair, skin, and nails. He notes that some people might be deficient, especially if consuming a lot of eggs with avidin, but doesn't consider it the 'Mecca of perfect hair'.
- Recommends ensuring sufficient biotin intake, either through diet or supplementation, if hair and nail health is the focus, as it acts as a co-factor for collagen to organize into robust matrixes.
- Takes biotin because her hair had stopped growing for a year, and it has helped her hair grow again.
- Highlights Vitamin B7, or biotin, as beneficial for hair, skin, and nails, but emphasizes its importance for high blood sugar and carb metabolism by increasing insulin receptor sensitivity and glucose tolerance.
- Explains that vitamin B7, also known as biotin, is important for controlling high blood sugar, which plays a role in fat accumulation.
- Warns that 16,000% of the daily value of biotin is overkill and the body will not utilize that much.
- Discusses a Youtheory hair, skin, and nail formula with collagen and biotin, noting that while it's not bad for the price, a powdered supplement form would likely be better.
- States that biotin is super important for synthesizing collagen and is good for hair, skin, and nails.
Andrew Huberman · Biotin · neutral
- Mentions biotin.
- Discusses biotin-enriched shampoos as a potential way to offset dryness and brittleness from ketoconazole, noting that while sufficient biotin is important, it's unclear if these shampoos significantly enhance biotin incorporation into hair.
Siim Land · Biotin · neutral
- Siim Land's company has published papers and filed patents for improvement in mitochondria in the skin using their core mitochondrial approach and other things like biotin.
- Mentions biotin as a nutraceutical with anti-thrombotic potential, increasing cyclic GMP.
- Recommends Biotin (Vitamin B7) for maintaining youthful skin, hair, and nails.
Dr. Rhonda Patrick · Biotin · warns
- Advises avoiding biotin-containing supplements before a testosterone blood test as they can cross-detect with estrogens and confound results.
- She occasionally uses biotin for hair and nails, meaning about twice a week.
Peter Attia · Biotin · warns
- 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.
- 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.
- Finds it silly to suggest that one needs to supplement biotin levels.
- Warns that biotin alone will not substantially improve female or male pattern hair loss, but it can make existing hairs stronger and needs to be coupled with other effective treatments.
Ben Greenfield · Biotin · recommends
- Recommends biotin (Vitamin B7) for supporting keratin production and strengthening hair, noting it can be found in eggs, almonds, and salmon.
- Warns that biotin could mess with a blood test and make certain lab tests unreliable if used leading up to the test.
- Warns of biotin deficiency on a carnivore diet, as it is low in meat but found in organ meats like liver, heart, kidney, and thymus glands.
- Notes that Kino Octane contains biotin and mentions that some men deficient in biotin notice a bump in testosterone when taking it.
- Mentions that the individual's microbes are producing good vitamins, including thiamine, biotin, and menaquinone (vitamin K2).
- Lists Biotin as a micro-nutrient that, if deficient, can hinder fat loss.
- Mentions biotin as one of the most significant micronutrients whose deficiency can prevent fat loss.
- Notes that the user has a lower likelihood of gut bacteria producing biotin, which can be found in foods like nuts and seeds.
- Used to consider taking enough Biotin for postpartum hair loss, but realized it was a hormonal issue that settled down on its own.
- Recommends biotin as a foundational nutrient for healthy methylation.
Dr. Mark Hyman · Biotin · recommends
- Recommends supplementing with biotin for hair follicle health and growth.
- Includes biotin as part of the IV drip protocol for detoxification.
- Mentions biotin as one of many nutrients that can be helpful for insulin resistance.
- Recommends biotin as helpful for insulin resistance and regulating blood sugar.
- Notes that biotin was among the compounds identified to regulate inflammation in a clinical trial.
- States that biotin is critical for regulating blood sugar.
- Notes that biotin can play a big role in hair loss, as it's made by gut bacteria, so a poor microbiome might lead to insufficient biotin production.
- Recommends ensuring adequate intake of biotin (B7), found in organ meats, for healthy hair, skin, and nails, noting that gut bacteria also produce it.
- States that biotin can be helpful for some people with hair problems, especially when biotin levels are low, which can lead to breaking hair and nails.
- Dr. Hyman mentions biotin as an important nutrient for hair and nails, noting that low levels can lead to breaking hair and nails, and it is produced by gut bacteria.
Bryan Johnson · Biotin · neutral
- 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.
- Recommends adequate Biotin (Vitamin B7) for hair health, noting it is in the Blueprint stack.
RAL Summary
Members OnlyTier 4 for Healthy Aging
Tier 4 fits: no human studies test biotin for aging or DNA repair, and only 5 reviews were counted, too few to support a higher tier.
- Emerging: not enough evidence to rank higher yet.
- No human studies on this goal for its ingredients.
More Details
Members OnlyBody systems · Combine with · Possible side effects
Body systems: Metabolism
Combine with: Combine with a healthy diet and lifestyle.
Possible side effects: No major side effects reported.
Supplement Facts
Biotin 1000 mcg
| Biotin | 1,000 mcg |
Other ingredients: Calcium Carbonate, Cellulose, Silica, Contains <2% of:.
Directions: Directions: For adults, take one (1) tablet up to two times daily, preferably with meals. As a reminder, discuss the supplements and medications you take with your health care providers.
Barcode (UPC) 301220467339 · Label source: NIH label database · Report a label change
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Graded November 14, 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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