Biotin is an essential nutrient also known as vitamin B7, which is integral for numerous enzymatic actions in the brain and body [1]. Despite humans needing biotin to do everything from metabolizing food to supporting neurological function, we cannot create our own internally, which makes us reliant on food sources and intestinal bacteria [2].

The most common foods with biotin include animal liver, egg yolks, cow milk, and various fruits and vegetables [3]. While having deficient levels of biotin is rare, many people do not have the optimal level, which can negatively impact regulation of energy and contributes to cognitive decline [4].

Also Known As

Vitamin B7, Vitamin H

Editors’ Thoughts on Biotin

Even though biotin would have normally been easy to consume in high quantities, modern diets don’t seem to support as much. Consider that the greatest source of biotin is in animal liver, which few people eat today. Similar to the high quantity of choline in liver, we are missing out on a crucial nutrient because of our changing dietary choices.

For some people, such as myself, who try to go mostly dairy free, it may be even more challenging. Biotin is found in egg yolks, but the other large source is cow milk. For people who are vegan, it might be a good idea to supplement with biotin.

Mansal Denton, Nootropedia Editor


Benefits of Biotin

As Nootropedia is a resource that revolves around cognitive performance, it is fitting to start first with the benefits of biotin for the brain. Because biotin is so key for the creation and action of certain enzymes, it plays a big role in the brain.

For example, a 2008 study in Pediatric Radiology concluded that biotin is necessary to develop healthy myelin sheaths around our nerves. This myelin sheath (a fatty layer over the nerves) allows us to better develop memories and prevent autoimmune diseases that affect cognition [5]

A deficiency in biotin (and even a suboptimal level) can create a host of cognitive problems including seizures, poor muscle coordination, learning disabilities, and depression. Some people also experience lethargy when they are deficient in biotin, which is one reason why vegans should be extra careful that they get enough of this essential nutrient [6].

Aside from the brain benefits of biotin, there are numerous others that are more commonly known. Many people buy biotin for promoting healthy skin, hair or nails because the nutrient is essential for metabolizing fatty acids [7].

There is evidence that biotin can help aid in a healthy immune system as well. In one study, scientists found that biotin was needed for the body to produce white blood cells. Without a high quantity of these cells, people suffer from increased risk of infection and pro-inflammatory cytokines [8]. This may also be why biotin may protect against certain types of cancer [9].

Like any essential nutrient that humans cannot synthesize, it’s important to get enough biotin in our diet or through supplementation. Failure to do so may not create immediate adverse effects, but will cause health problems over time.

Side Effects of Biotin

Most people who experience side effects of biotin are either taking too high of a dose or simply have gastro-intestinal distress from the supplement. There are some nutrient interactions between biotin and others, which can also create issues in theory and practice.

For example, some evidence shows that ALA (alpha lipoic acid) interacts with enzymes that are dependent on biotin [10]. There isn’t a clear consensus on how that impacts supplementation of biotin, however.

Finally, there is a side effect of biotin in combination with alcohol. It isn’t anything dangerous, but drinking alcohol reduces the absorption of biotin.

Biotin Dosage

The adequate biotin dosage according to the recommended daily intake (RDI) is around 25 – 100 mcg per day. Most multivitamins have biotin in a 30 mcg dosage, which is perfect for children and adults alike. Some people (especially vegans) may want to opt for a higher dosage in the 100 mcg range.

In one study, humans safely used 2500 mcg over 6 months to improve brittle nails without any adverse effects. This suggests a higher dose is tolerable, but not necessary.

How and Where to Buy Biotin

There are dozens of biotin products that you can find online or in a local grocery store. If you purchase biotin, it is best to do so online for cost purposes. More than likely anything you find will be relatively safe (this is an essential nutrient after all).

We recommend you buy biotin online utilizing Amazon and specifically the brand Nature Made, which has a higher dose range of 2500 mcg. That being said, most of the products you can find online sell 10,000 mcg, which is much higher than the recommended dosage. Why they are selling a high dose like this is unknown, but we recommend starting lower.

There is no need to buy biotin if you are eating animal liver, drinking a high quantity of cows milk, and eating eggs. It is especially important to buy biotin if you are a vegan or vegetarian, however.

Biotin Reviews

For people that are deficient in biotin, this supplement can be a life saver (literally). Biotin reviews online are probably skewed as a result. People who are deficient (the numbers range, but usually 1 in 120 people) find that biotin supplements are great for improving their cognitive and physical performance.

Because it is an essential nutrient, people who review biotin favorably after using it for a while typically have great results, but they are not indicative of what you might experience using them to improve mental (or physical) performance. Take the biotin reviews with a grain of salt as a result of the skewed data by deficient individuals.

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