Biotin is a B vitamin that plays a critical role in a wide range of bodily functions. It’s sometimes also known as vitamin B7 or vitamin H, and it appears to impact your body’s ability to synthesize proteins for skin, hair, and metabolic functions involving fat or glucose.
The research on biotin is still in its early stages, but people are hopeful that it can be used to improve hair thickness, fight brittle nails, and even improve metabolic health and control blood sugar.
Our research team looked into the best biotin supplements out there; here’s what we came up with.
1. Natrol Biotin Maximum Potency
Natrol makes a high-dosage biotin supplement with a little bit of calcium added (66 mg to be exact). It comes in a vegetable cellulose capsule and is free from most common allergens like dairy, soy, and nuts.
Its dosage is on the high end, at 10,000 micrograms. Natrol also makes lower dosage biotin supplements, but these aren’t as popular.
2. Sports Research High Potency Biotin
Sports Research is known for high-quality supplements, and their biotin offering fits the bill.
With 10,000 micrograms of biotin and the United States Pharmacopeia mark guaranteeing extremely high purity and dosage accuracy, it is a very solid go-to biotin supplement. The compound is dissolved in coconut oil and beeswax, and comes in a vegan-friendly softgel.
3. Solgar Super High Potency Biotin
Solgar makes a simple, straightforward, no-BS biotin supplement. It delivers 10,000 micrograms and nothing else, save for a vegetarian-friendly cellulose capsule and a few binders to hold the capsule together.
Given Solgar’s good reputation for purity, it’s a good buy for anyone who wants a minimalist high-dose biotin supplement.
4. Zhou Hairfluence
Zhou Hairfluence is more of a total solution to hair thickness and fullness—yes, it’s got biotin, but it’s also got about a dozen other ingredients, including other B vitamins, pantothenic acid, MSM, collagen hydrolysate, and even pure keratin (the protein hair is made out of).
The theory here is to load up your body with all the ingredients it needs to pump out hair as fast and as thick as possible. As a biotin supplement, it functions pretty well, delivering 5,000 micrograms per dose (however, do note that a dose is two capsules, not one).
Zhou Hairfluence is well-reviewed, so if you want a multi-ingredient hair supplement, this is the one to go with. If all you want is biotin, there are better options.
5. NOW Biotin
NOW Biotin is a safe bet for a simple biotin supplement. NOW is a large and fairly well-regarded vitamin and supplement company, and their 10,000 microgram biotin supplement is pretty solid: no red-flag ingredients and no common allergens.
NOW also makes a 1,000 and 5,000 dose version of their biotin supplement, too.
6. Zenwise Health Extra Strength Biotin
Zenwise’s biotin supplement doesn’t distinguish itself in any particular way. Its dosage is middle of the road, at 5000 micrograms, and it doesn’t have any real extraneous ingredients.
It has a vegetable capsule, which is good, and it’s free of most common allergens, which is also a plus.
7. OmegaBoost Biotin
OmegaBoost provides a 5000 microgram biotin supplement alongside 222 mg of calcium. This represents a substantial amount of calcium; 225 of your recommended daily intake to be exact.
While there’s no evidence that there is any synergy between biotin and calcium when it comes to hair, skin, or nail strength and health, some people do suspect that calcium (along with a host of other nutrients) play a role.
8. VitaFusion Extra Strength Biotin
VitaFusion’s biotin is the only gummy-based supplement on the market, so it’s one of your only options if you don’t want or don't’ like pill based supplements.
You do have to be okay with the fact that these gummies are gelatin-based and include some artificial flavoring and coloring, though. At 5,000 micrograms per dose, they are middle of the road when it comes to dosage.
9. Nature’s Bounty Biotin
Nature’s Bounty offers a few different dosages of biotin, but the 10,000 microgram version is the most popular. While it’s pretty simple to make a biotin supplement, Nature’s Bounty seems to have cut a few corners here.
The biotin is dissolved in soybean oil, which won’t sit well with the anti-soy crowd, and the capsules are colored with titanium dioxide (for aesthetic purposes).
10. SBR Nutrition Biotin
SBR Nutrition’s biotin supplement is unique in its form of delivery. It comes in a dropper bottle, which allows you to measure out arbitrary dosages of biotin.
The problem with this is that the dropper delivery method is not very precise, so you are going to get wildly different doses from day to day. It is flavored with natural vanilla and stevia to make the taste palatable, but unless you really dislike pills or have a good reason for wanting a liquid source of biotin, you should probably just opt for a capsule-based supplement.
Biotin benefits and side effects
The B vitamins are a versatile and critically important group of nutrients, and biotin is no exception. Vitamin B7, as it's sometimes known, helps grow your hair, strengthen your nails, and process fats and sugar in your diet.
Despite this, it’s still a fairly new nutrient in the world of nutrition, so the full breadth of its utility isn’t yet known. Many people swear by biotin’s ability to help you grow thicker hair, stronger nails, and even control your weight and blood sugar.
Biotin initially arose interest from the supplementation when people started taking note of the effects of biotin deficiency. A small percentage of people are born with a genetic defect that prevents their body from effectively metabolizing biotin.
A case study published in The Lancet in 1979 describes how biotin deficiency can cause marked hair thinning and a biological imbalance of enzymes in the blood (1). Upon administration of a biotin supplement, all of these symptoms reversed rapidly.
Other work, such as a review by D.M. Mock, has found that a lack of biotin can cause dry, scaling skin, as well as the proliferation of yeast infections in the skin and an impairment of immune system function (2).
All this raises an obvious question: can supplemental biotin cause the inverse of these effect? In at least some cases, the answer appears to be yes.
A scientific study published in 1993 in a journal on skin and nail conditions looked at patients who reported to a dermatology clinic with brittle nails (3).
The study evaluated the patients and prescribed them a biotin supplement to take for a period of several weeks.
Of the patients who took the biotin supplement, 63 percent showed a substantial improvement in their nail condition. Though the other 37 percent saw no improvement, we need to keep in mind that many conditions can cause nail brittleness.
If fully two-thirds of people with brittle nails respond to a biotin supplement, this suggests that biotin deficiency is more widespread than previously thought, at least among people with brittle, thin nails.
The primary effect of the biotin supplementation in these patients who responded to the therapy was an increase in nail thickness. Other research found similar results, and biotin has even been used in cattle and cows to increase the thickness of their hooves.
This might not seem particularly relevant for hair thickness, but consider this: despite their vastly different appearance, fingernails and hair (as well as cattle hooves and horse hooves) are actually made of the same thing.
The protein keratin is the primary thing that makes up both your nails and your hair, and that’s exactly the protein whose synthesis appears to be increased by biotin in the people who took the biotin supplement for brittle nails.
So, from this, it follows that people with thin or brittle hair might respond in the same way to a biotin supplement.
If the response rate was similar, a large proportion of people could see substantial changes in their hair thickness–up to 25%, if the gains in nail plate thickness from biotin supplementation mirror those of hair follicle thickness.
Experiments testing this hypothesis directly are lacking, but that hasn’t stopped people from exploring its use as a method to increase hair thickness and strength. Reviews are mixed, but some people do find that biotin supplements help them achieve stronger and fuller hair.
Don’t make the common mistake of thinking that biotin is for preventing hair loss–unlike other supplements that are supposed to prevent hairs from falling out, there is no evidence yet that biotin does that.
What it might be able to do is make the shafts of hair you do have grow thicker and stronger–again, this is based off research on nail plate growth, extrapolating from the fact that hair and nails are made from the exact same protein.
Interestingly, biotin also seems to help control blood sugar. Research published in 2008 in the scientific journal Diabetes Metabolism Research and Reviews tested the effects of a biotin and chromium picolinate supplement on blood sugar levels in overweight and obese people who had type 2 diabetes (4).
In a placebo-controlled trial, the supplement was able to lower their blood sugar levels substantially, leading the researchers to recommend it as a secondary treatment for type two diabetes.
Obviously, you’d want to talk to your doctor about this if this is relevant to you, but it’s an interesting direction for future research.
The role that biotin plays in your body is not limited to hair, skin, and nails, as this study shows. Biotin plays a key role in a wide range of cellular interactions inside your body, so the full extent of its health benefits have likely not been fully researched.
As a B vitamin that occurs in a host of food products, it’s hard to get too much biotin. There is no well-characterized side effect profile.
According to the Mayo Clinic, there are no known side effects of biotin supplementation, even up to 10 mg per day–this is on the high end of what’s available as an over-the-counter supplement (5).
The recommended daily intake for biotin is pretty small compared to what’s available in a supplement. Data published by the National Institutes of Health’s Office of Dietary Supplements outlines a minimum intake of 30 micrograms of biotin per day for healthy adults (6).
However, this dosage is just to maintain normal, healthy levels of the vitamin. As for strengthening nails or increasing hair volume and thickness, doses may need to be higher, though how much higher is not clear.
Because biotin has an excellent safety profile, the good news is that you can experiment with a wide range of doses to see if biotin is effective for you. Try a few different dosage levels to see what works for you; there isn't enough research yet to properly characterize how much biotin you need to get the benefits.
It’s probably best not to stray beyond 10 mg per day (equivalent to 10,000 micrograms) per day, since the safety of biotin hasn’t been evaluated beyond this level.
That is already a couple hundred times your normally-required daily intake, so if there was an effect of biotin, you’d expect to see it by that point.
Biotin is a very safe B vitamin supplement that might help you grow thicker hair, repair brittle and thin nails, and even control your blood sugar.
It’s safe in doses at least up to 10 mg per day, and though the research on its uses is in its early stages, there are promising signs that it could be effective at improving the health of your skin, nails, hair, and blood sugar control.