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biotin supplements with hair comb

Biotin for hair

20 Apr 2021 • 2 min read

Did you know there’s a Vitamin H? Well, there is, and it’s also called biotin.

Biotin is a water-soluble vitamin that happens to be part of the Vitamin B family, which is what we have to thank for helping our bodies turn food into energy.1

As for the name, ‘biotin’ it sounds a bit scientific, doesn’t it? Well, it actually stems from the ancient Greek word, ‘biotos’ which means ‘life’ or ‘sustenance.’ B vitamins, especially biotin, are widely recognised as going hand-in-hand with keeping our eyes, liver, and nervous system healthy. Meanwhile, biotin specifically is considered as being crucial during pregnancy because it plays an important role in embryonic growth.

Biotin is responsible for:

  • Processing the nutrients from our food
  • Energy release
  • Healthy hair, skin and mucous membranes
  • Normal nervous system3

The vast majority of people get their daily biotin intake from what they eat every day. Interestingly, it has been claimed boosting your biotin levels can help regulate blood sugar levels, boost hair growth and help with skin and nail health.

(For more on the Vitamin B family and what these vitamins do for the body, ‘What’s the best Vitamin B to take?’)

How do you take biotin?

Because biotin is a water-soluble vitamin, our body doesn’t store it, so it’s important you’re consuming it within your diet on a daily basis to keep your biotin levels topped up.

Good biotin food sources include3,4:

  1. Egg yolks
  2. Avocados
  3. Legumes – beans, peas and lentils
  4. Nuts and seeds
  5. Liver
  6. Yeast
  7. Mushrooms
  8. Sweet potatoes
  9. Broccoli
  10. Bananas
  11. Pork
  12. Carrots
  13. Apples
  14. Chicken
  15. Lettuce

You can also take biotin in supplement form too, and the recommended intake for adults is between 30 and 100 micrograms (mcg) a day.

Children need:

  • 6 months to 1 year old – 6mcg of biotin a day
  • 1 to 3 years old – 20mcg of biotin a day
  • 4 to 10 years old – 25mcg of biotin a day
  • Adolescents – 35mcg of biotin a day

Meanwhile, it’s also possible to use biotin topically too. There are specific hair growth and thickening shampoos on the market you can apply directly to your hair.

Does biotin help hair growth?

Our hair, skin and nails all contain a basic protein called keratin. You may recall some haircare and skincare products being enriched with keratin?7

Well, studies have found that biotin can improve the keratin infrastructure within our bodies. How this actually happens, and how biotin helps hair and skin health, is still very much a mystery.

Some research has been carried out, but evidence of biotin for hair growth, along with beard growth, remains limited. Among the research includes a study that was carried out in 2015, in which women with thinning hair were given an oral Marine Protein Supplement (MPS) that contained biotin or a placebo pill twice a day for 90 days.

At the start 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. Researchers found that women who took an MPS experienced a significant amount of hair growth in the areas affected by hair loss and less shedding.

The bottom line: Biotin can only impact hair growth if there is an existing biotin deficiency. Taking extra biotin supplements does not lead to extra nutrient-based hair growth.8

How much biotin should I take for hair?

Based on general guidance, it’s recommended people take between 2,000 and 5,000 mcg of biotin as a supplement to strengthen hair shafts and potentially see positive hair results.9

If you are planning on taking biotin for hair growth or beard growth, speak to your GP first, especially if you are experiencing hair loss. Seeking professional medical will help to diagnose the cause of your hair loss and recommend a suitable treatment.

How long does biotin for hair growth take to work?

If you have a biotin deficiency, for instance, some women can be slightly deficient in biotin when they are pregnant or breastfeeding, it can take several months for you to start seeing a difference with your hair. The improvements are likely to be subtle too.10

Can biotin cause hair loss?

Although biotin deficiency is considered to be rare, it can result in hair loss that can be addressed with supplementation. If you have symptoms of biotin deficiency or are thinking of taking it, be sure to talk with a medical professional to assess your levels and discuss what's best for you.11

It's possible for people who drink excessive amounts of alcohol or eat a lot of raw egg whites to develop a biotin deficiency. Genetic disorders and smoking can also potentially cause lead to a reduction in biotin within the body.

You’re also more prone to developing a biotin deficiency if you have a condition that impacts your digestive tract, such as an inflammatory bowel disease or bacterial overgrowth within your small intestine. This is due to the fact that biotin is naturally produced by certain gut bacteria that are present within the intestines - any condition that throws off the microbes in there can impact the effective production of biotin.12

Symptoms of biotin deficiency:

  • Thinning hair
  • Brittle nails
  • Dry skin
  • A red scaly rash (especially around the eyes, nose and mouth)
  • Conjunctivitis
  • Exhaustion
  • Hallucinations
  • Numbness and tingling of the arms and legs

While being deficient in biotin is considered to be rare, it can sometimes result in hair loss that can possibly be helped by taking biotin supplements. Again, make sure you speak to your GP first before taking biotin supplements.

What are the side effects of biotin?

Most people can take biotin supplements without experiencing any side effects. However, it is possible for people to take them and experience13:

  • Nausea
  • Diarrhoea
  • Cramping

If you do happen to experience any of these side effects, then you may want to take your biotin supplements with food, as it’s thought that this can help minimise these issues. Following the recommended guidance from your GP and the manufacturer, and making sure you stick to the dosage, will also help minimise the likelihood of you experiencing side effects.

If you happen to have any extra biotin in your body, it will naturally be flushed out of your system when you urinate. As a result, overdosing on biotin is considered to be rare however, it is still a possibility. Symptoms of biotin overdose include14:

  • Low Vitamin C levels
  • Low Vitamin B-6 levels
  • High blood sugar levels
  • Drop in insulin production

Does biotin only potentially help with hair growth?

No, people do take biotin for other things too which, unlike the link between biotin and hair growth, are backed up with more evidence.15

One of the main benefits of taking biotin is that it can support a healthy metabolism. Biotin converts glucose from carbohydrates into energy for the body and aids amino acids in carrying out normal bodily functions.

Other biotin benefits:

  • Supporting cognitive function
  • Maintaining normal blood sugar in people with diabetes
  • Increasing ‘good’ HDL cholesterol and reducing ‘bad’ LDL cholesterol levels

To sum things up…

Biotin is believed to help support our hair, skin and nails, as well as deliver several other health benefits. However, biotin’s ability to help in these three areas, particularly hair, is yet to be widely proven.

It’s possible to get all the biotin you need, simply by eating a healthy, balanced diet, as there’s a wide range of biotin-rich food out there (the examples above are literally the tip of the iceberg). Biotin deficiencies are rare and it’s impossible to have too much of it in your system because your body naturally gets rid of an excess biotin when you urinate.

If you’re planning on taking biotin supplements for hair loss or beard thinning, seek medical advice first to try and identify the root cause of the problem.

We hope that you’ve found this article useful and that it’s helped answer some of the questions you may have had in relation to using or taking biotin for hair. If you’re looking for other ways to help boost your hair, check out this article, ‘How to get thicker and longer hair: 10 top hair-boosting tips & tricks.

Last updated: 7 April 2021



Author: Bhupesh PanchalSenior Regulatory Affairs Associate

Joined Holland & Barrett: Apr 2019

Masters Degree in Toxicology and BSc Hons in Medical Biochemistry

Bhupesh started his career as a Clinical Toxicologist for Public Health England, advising healthcare professionals all around the country on how to manage clinical cases of adverse exposure to supplements, pharmaceuticals, cosmetics, industrial chemicals and agricultural products.

After 7 years in this role and a further year working as a drug safety officer in the pharmaceutical industry, Bhupesh joined Holland & Barrett as a Senior Regulatory Affairs Associate in 2019.

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