Vitamin B7 (Biotin)
Vitamin B7 is an essential water-soluble vitamin that has many uses within the body. It is involved in more bodily processes than any other vitamin or mineral.Amongst its vital roles are:
- assists four essential enzymes that break down fats, carbohydrates, and proteins
- that plays an important role in metabolizing the energy we get from food
- maintaining the proper functioning of the nervous system
Processing, cooking in water, defrosting and extremes of pH will remove B7 from foods
B7 occurs in very low concentrations in many natural foods, but is quite easily lost. Foods that are a good source of B7 include: whole grains, nuts, egg yolks, sardines, legumes, liver, cauliflower, bananas, and mushrooms. Egg whites can prevent the absorption of B7.
We may be able to get B7 from bacteria living in the digestive tract.
It is not yet clear whether the body can utilise this source of B7 though.
Your lifestyle may increase the risk of deficiencyAside from a poor diet, deficiencies can occur due to:
- alcohol intake
- heavy exercise
- high stress
B7 deficiency is rare, but even a moderate deficit has health consequences. Some of the symptoms of mild deficiency are similar for all B Group vitamins:
- energy production is reduced which can cause tiredness, irritability, fatigue, and apathy.
- nervous system symptoms such as muscle weakness, cramps and numbness.
In addition, mild B7 deficiency may cause: weak or brittle fingernails, dry or scaly skin and skin rashes.
There is no RDI for B7, however Adequate Intake (AI) levels have been established:
|Age||Adequate Intake (AI)|
|Girls||14-18 yr||25 mcg/day|
|Boys||14-18 yr||30 mcg/day|
|Girls||9-13 yr||20 mcg/day|
|Boys||9-13 yr||20 mcg/day|
|Children||4-8 yr||12 mcg/day|
|Children||1-3 yr||8 mcg/day|
* Source: Nutrient Reference Values for Australia and New Zealand. National health and Medical Research Council
There is insufficient evidence of adverse effects in humans or animals to set a maximum dose for any age.