Vitamin B8 (biotin)
Vitamins
It takes part in making fatty acids and glucose.
Part of it comes from colon bacteria. RAW egg white, conversely, blocks it: it is the only documented dietary case of induced deficiency.
Effects and benefits
The hair and skin vitamin, all over advertising. It contributes to energy, nerves and normal hair, skin and mucous membranes; but as a high-dose supplement, it skews blood tests.
It serves as a carbon dioxide clamp for five enzymes that make glucose and fats. It contributes to normal energy-yielding metabolism, to the normal functioning of the nervous system, to normal macronutrient metabolism, to normal psychological function and to the maintenance of normal hair, skin and mucous membranes (Regulation 432/2012).
In people who are not lacking, no trial has shown that taking more makes hair more beautiful. High-dose supplements, at 5 or 10 mg, on the other hand skew common blood tests, from the thyroid to the troponin of heart attacks; the US Food and Drug Administration issued a warning in 2017 (FDA, 2017).
EFSA sets the adequate intake at 40 µg a day for an adult, and 45 during breastfeeding (EFSA, 2014).
Sources: EU Regulation 432/2012 · FDA, 2017 · EFSA, 2014
Where to find it (11)
- Almond
- Black soybean
- Button mushroom
- Grenoble walnut
- Nutritional yeast
- Oats
- Peanut
- Soybeans / edamame
- Spinach
- Sunflower seeds
- Sweet potato