Vitamin H is another name for vitamin B7 which is more commonly known as biotin. Biotin supplements are widely taken to support hair and skin health, and it is often included in beauty products, although it offers other more widespread benefits, too.
What is it?
Biotin is a water-soluble member of the vitamin B group. Its name is derived from the Greek word ‘biotos’, meaning ‘life’ or ‘sustenance’. As well as being found in the diet, some probiotic bacteria in the bowel make biotin which can be absorbed.
What does Vitamin H do?
Biotin has long been associated with beauty for its vital role in promoting the growth and repair of your hair, skin and nails. Biotin is also needed for the metabolic reactions that break down food components to make energy and for the synthesis and metabolism of glucose, fatty acids, amino acids. It also supports normal psychological function and the nervous system.
The EU have reviewed all the evidence and concluded that biotin makes an essential contribution to:
- the maintenance of normal hair
- the maintenance of normal skin
- the maintenance of normal mucous membranes
- normal psychological function
- normal energy-yielding metabolism
- normal functioning of the nervous system
- normal macronutrient (ie protein, carbohydrate and fat) metabolism
Vitamin H for nails
Biotin supplements are used to treat several nail conditions with promising results. In women with brittle nails, biotin increased nail plate thickness by 25% as determined by scanning electron microscopy. Splitting of nails also reduced as a result of improved regularity of the cell arrangement on the back surface of the nails. It is only likely to help if you are biotin deficient, however – in one study, 63% of people showed clinical improvement while 37% showed no change.
Vitamin H for glucose control
Biotin is needed for the proper function of an enzyme, glucokinase, which plays a role in the metabolism of glucose. Blood levels of biotin are usually lower in people with type 2 diabetes than in those without, and biotin supplements have the potential to improve glucose metabolism by stimulating insulin secretion from the pancreas and by increasing the breakdown of glucose in the liver. It may also have an effect on the glucose receptors (known as GLUT 4) that transport glucose into cells under the influence of insulin.
The few trials that have used biotin alone have involved small numbers of people but suggest biotin supplements have the potential to produce significant improvements in fasting blood glucose levels. Average reductions were 45% compared with those taking placebo.
A study involving 447 people with poorly controlled type 2 diabetes showed significant improvements in fasting glucose levels and (HbA1c – a measure of short term glucose control) in those taking both chromium picolinate and biotin supplements daily.
Who is deficient?
Lack of biotin affects the function of some metabolic enzymes and may result in low blood sugar levels (hypoglycaemia) between meals. Deficiency has also been associated with dry, flaky skin, a rash around the nose and mouth, brittle hair, patches of hair loss, reversible baldness, tiredness, loss of appetite, nausea, depression, muscle pains and wasting.
Dietary deficiency of biotin can occur in those following very low-calorie weight loss diets and in people who eat large amounts of raw egg white over a long period (eg body builders). This is because raw egg white contains a protein, avidin, which binds biotin in the gut and prevents its absorption. Cooked egg white does not have this effect.
Long-term antibiotic treatment (eg for acne) can also lead to deficiency due to loss of the normal probiotic bowel bacteria that make biotin.
It’s estimated that one in every 123 people has an inherited inborn error of biotin metabolism. This is believed to affect their immunity against yeast infections and may be linked with recurrent thrush infections. In such cases high-dose biotin supplements will solve the problem if biotin deficiency is to blame.
Where can we get it?
Biotin is widespread in the diet and good sources include meat, liver, oily fish, whole grains, rice, nuts, cauliflower, egg yolk and yeast extracts. It is also produced by probiotic bacteria in the bowel, from which it can be absorbed.
Check our recipe for delicious Japanese roast cauliflower in Dengaku sauce.
Biotin supplements
Most multivitamin supplements contain the normal recommended daily amount (or nutrient reference value) for biotin which is 50mcg (micrograms). High strength supplements supplying 1,000ug (1 milligram) of biotin are also available to promote healthy skin and nails. Try Healthspan’s new Biotin supplement within their nurture skincare range (3 month supply £9.95).
What to avoid
Do not exceed the manufacturer’s recommended daily dose.
To find out further information about supplements or if you have any queries about taking supplements you can visit healthspan or speak to a qualified nutritionist.
About A-Z of vitamins and minerals
A to Z of vitamins and minerals is a guide by Dr Sarah Brewer who is the Medical Director at wellbeing brand Healthspan and Rob Hobson who is a Registered Nutritionist.
About the Author / Sarah Brewer
Dr Sarah Brewer is a regular contributor to 50connect, she qualified from Cambridge University with degrees in Natural Sciences, Medicine and Surgery. After working in general practice, she went on to achieve her master’s degree in nutritional medicine from the University of Surrey. As well as being a licensed doctor, Sarah is now also a Registered Nutritionist, Registered Nutritional Therapist and an award winning health writer. Dr Brewer writes widely on all aspects of health and nutrition, including complementary medicine and the safe use of herbal remedies and vitamin supplements. She has written over 50 popular self-help books, is the Editor of YourWellness magazine, and a regular contributor to national newspapers and key women’s publications. Sarah is married with three children and lives in the Channel Islands.
