Biotin is a water-soluble vitamin that’s a part of the vitamin B family. It’s also known as vitamin H. Your body needs biotin to help convert certain nutrients into energy. It also plays an important role in the health of your hair, skin, and nails.

If you aren’t getting enough biotin, you may experience hair loss or a scaly red rash. However, a deficiency is rare. In most cases, the biotin you get from your diet is enough for you to reap the health benefits it offers.

Still, many people are increasing their intake in hopes of additional benefits. Keep reading to find out how to add biotin to your diet, what to look for in a biotin supplement, possible side effects, and more.

Keratin is a basic protein that makes up your hair, skin, and nails. It’s clear that biotin improves your body’s keratin infrastructure. But beyond that, researchers aren’t really sure what biotin’s role in hair or skincare is.

Research on the effects of biotin on hair growth is sparse. To date, there’s only limited evidence to suggest that increased biotin intake may help promote hair growth.

For example, in one 2015 study, women with thinning hair were given an oral marine protein supplement (MPS) containing biotin or a placebo pill twice per day for 90 days. At the beginning and end of the study, digital images were taken of the affected areas on the scalp. Each participant’s hair was also washed and any shed hairs were counted. The researcher found that women who took an MPS experienced a significant amount of hair growth in the areas affected by hair loss. They also had less shedding.

A 2012 study by the same researcher produced similar results. Participants perceived improvement in hair growth and quality after 90 and 180 days.

Check out: Other B vitamins for hair growth »

Biotin deficiency is rare, so the U. S. Food and Drug Administration doesn’t offer a recommended dietary allowance (RDA). RDAs can vary based on a person’s age, sex, and overall health.

Instead, experts recommended the following dosage guidelines. Anyone aged 10 or older should get between 30 and 100 mcg per day. Infants and children should get:

  • birth to 3 years: 10 to 20 micrograms (mcg)
  • ages 4 to 6 years: 25 mcg
  • ages 7 to 10 years: 30 mcg

Women who are pregnant or breastfeeding may need higher levels of biotin.

Talk with your doctor about the right daily intake for you. They can provide guidance on how to safely increase your dosage to provide the maximum benefits. You can fulfill your recommended biotin allowance through your diet or by taking a biotin supplement.

You’re probably already getting the daily recommended amount of biotin from the food you eat. But if you’d like to increase your intake, you can add more biotin-rich foods into your diet.

These include:

  • organ meats, such as liver or kidney
  • egg yolk
  • nuts, such as almonds, peanuts, and walnuts
  • soybeans and other legumes
  • whole grains
  • bananas
  • cauliflower
  • mushrooms

Heat can reduce biotin’s efficacy, so opt for raw or minimally-processed dishes. The amount of biotin can vary from food to food, too, so be sure to read the nutritional information whenever possible. This can help you select items with the most biotin for your buck.

If you don’t think you’re getting enough biotin from your diet, or if you’re just looking to up your dosage, supplements may be an option.

Biotin supplements are available over the counter in capsule or tablet form. You can find a great selection of biotin supplements here. Although dietary supplements are regulated by the U.S. Food and Drug Administration, it’s important to read the packaging carefully and only purchase from a supplier you trust.

Most people can take biotin supplements without any adverse effects, but minor side effects are possible. These include:

  • nausea
  • cramping
  • diarrhea

You may be able to reduce your risk of side effects by taking your supplement with food. Supplements aren’t for everyone, so talk with your doctor before use. They can talk to you about the potential risks and benefits, as well as the proper dosage. You should always follow the dosage information on the label unless your doctor instructs otherwise.

Although more research is needed to assess its effects on hair growth, biotin does have several proven benefits.

For example, biotin is one of several B vitamins that supports a healthy metabolism. Biotin converts glucose from carbohydrates into energy for the body and aids amino acids in carrying out normal bodily functions.

Biotin is also thought to:

  • reduce inflammation
  • improve cognitive function
  • help lower blood sugar in people with diabetes
  • increase “good” HDL cholesterol and decrease “bad” LDL cholesterol

Keep reading: The benefits of biotin »

Adding more biotin-rich foods to your diet doesn’t carry any risks. However, you should always check with your doctor before adding a new supplement to your routine. Biotin doesn’t have any known interactions, but your doctor should still confirm supplement use alongside any other medications you may be taking. Your doctor can also provide more individual information about dosage and potential side effects.

Biotin is a water-soluble vitamin, so any extra biotin in your body will flush out through your urine. This makes a potential overdose unlikely. If you develop an unusual or unexpected skin rash after increasing your biotin intake, see your doctor. In rare cases, this is a sign of biotin overdose.

Your doctor will check for the following to confirm an overdose:

  • low vitamin C levels
  • low vitamin B-6 levels
  • high blood sugar levels
  • decline in insulin production

If your doctor confirms that you’re getting too much biotin, they will reduce your recommended dosage.

Most people won’t see any noticeable benefits until they’ve increased their intake for several months. For best results, you should be consistent in your intake. If you’re increasing your intake through food, you’ll need to eat several biotin-rich foods on a daily basis to actually ingest enough biotin to make a difference. If you’re taking a supplement, it’s important that you take it daily or as directed by your doctor.

Although research is limited, studies from 2012 and 2015 suggest that results may be seen in as little as 90 days. This includes an increase in growth and shine. It’s thought that the longer you consume a higher dose, the better your results will be.

Keep reading: 6 tips to grow hair faster »

If you’re experiencing hair thinning or hair loss, biotin may assist in regrowth. There’s some research to suggest that increased biotin intake can improve overall hair quality, including thickness and shine.

You may already be getting the biotin you need through your diet, so talk with your doctor about the best option for you. They may recommend certain dietary changes or a biotin supplement. Be sure to follow any dosage guidelines that they provide.

If you begin having any unusual symptoms while taking a biotin supplement, discontinue use and see your doctor.