Who needs it?

Biotin is especially important in childhood. Helps the body to use the necessary fatty acids, participates in the metabolism of the skin ,hair and nerves.

Signs of deficiency

Dry skin , weak and early gray hair, painful and sensitive muscles , poor appetite and nausea, eczema and dermatitis.

How much?

RDA (recommended daily intake) 150 mcg
OPN (optimal daily intake) 225 mcg

Toxicity

Unknown.

Recommended foods

Cauliflower (1.5 mcg) ,lettuce (0.7 mcg),green peas (0.5 mcg) , tomatoes (1.5 mcg) ,oysters (10 mcg), grapefruit (1.0 mcg) , watermelon(4.0 mcg),sweet corn (6.0 mcg), cabbage (1.1 mcg) , almonds (20 mcg), Cherries (0.4 mcg) , Herring(10 mcg), milk (2.0 mcg) , eggs (25 mcg).

Assistants

Acts in combination with other vitamins of Group B , magnesium and manganese. It is best to take with complex B and food.

Thieves

Raw egg white, as it contains avidin, which almost does not remain in the boiled egg, and fried foods.

Source
Patrick Holford" the new Bible of optimal nutrition " P. 479-480 book publisher (Medical Research and Consulting Center)