Vitamin B7 - Biotin
The health benefits of vitamin B7 or biotin include improved metabolism, tissue maintenance and healthy skin. It also provides relief from heart problems, alopecia and Parkinson's disease. Biotin can be found in a wide variety of foods including animal liver, egg yolks, cow milk, and some fruits and vegetables
Vitamin B7 is a water-soluble nutrient that is part of the B vitamin family. It support adrenal function, help calm and maintain a healthy nervous system, steadying blood sugar levels (helps glucose uptake in muscle cells, and stimulates an enzyme in the liver that promotes glycogen synthesis), DNA stability and is necessary for key metabolic processes. B7 is essential for the metabolism of carbohydrate and fat.
In combination with chromium, biotin can help reduce heart disease risk factors by increasing high-density lipoprotein (HDL) levels and decreasing low-density lipoprotein (LDL) levels, especially in diabetic patients with heart disease
Pharmacological doses of biotin (15000 mcg/day) are also effective in lowering blood triglyceride concentrations in patients with elevated triglyceride levels.
Biotin deficiency is serious
Signs and symptoms of biotin deficiency. Signs of severe biotin deficiency include hair loss and a scaly red rash around the eyes, nose, mouth, and genital area. Neurologic symptoms in adults have included depression, lethargy, hallucinations, numbness and tingling of the extremities and seizures. Eating raw egg whites can have some serious effects on biotin. Egg whites contain avidin which is a protein that strongly binds to vitamin B7. There are some drugs that can lower biotin levels in your body. These include antibiotics and anti-seizure medications such as carbamazepine, phenobarbital, phenytoin and primidone. A dose of antibiotics can have a hugely negative affect on gut health.
Vitamin B7 supplementation
Supplementation is very safe, even at high doses. This may compensate for poor absorption or a high rate of excretion.
- B7 supplements only are typically in large dose quantities (2,500μg, 5000μg, 10,000μg)
- B complex supplements contain all the B vitamins including B7.
- Multi-vitamins: centrum for men contains 54μg (mcg).
Vitamin B7 Testing
Deficiency of vitamin B7 is very rare and so testing is not needed. But Urinary 3-hydroxyisovalerate is the most sensitive test for biotin deficiency.
How much vitamin B7 do I need?
The RDA for vitamin B7 is 30μg. But in reality, way more is needed due to excretion issues. However, vitamin B7s main use is in the metabolism of glucose and this RDA may vary with calorie intake. Multivitamins such as Centrum contain 54μg per dose. Pregnant women need lots of vitamin B7, as it is thought that 1/3 of pregnant women become deficient because of the needs of the baby. Daily supplementation of B7 decreased fasting blood sugar concentrations in patients with type 2 diabetes.
Vitamin B7 Foods
Liver (100g): 100mcg
Nutritional yeast (1tsp): 15mcg
Egg yolk: 10mg (Raw egg white contains avidin, a protein that binds biotin and prevents its absorption. Avidin is inactivated by heating, so the eggs must be cooked. Or just use the yolks).
Salmon (100g): 6mcg
Sunflower seeds (1/4 cup): 3mcg
Sweet potato (whole): 0.3mcg
Vitamin B7 intake strategy
Our advice is to take a vitamin B complex supplement or a multi-vitamin that contains B7. It's advisable to get a whole-food intake as well. The 2 super foods for vitamin B7 are liver and eggs (cooked). If you are not a liver fan you could try a liver pate or liver wurst). Raw egg whites have a negative binding affect with vitamin B7.
Adequate intake: 30μg per day.
Theraputic dose: 2,500-15,000μg for skin, nail and hair "possible" benefits.
Upper tolerable limit: 50mg (50,000μg).
Notes: B complex supplements are cheap and effective. Large dose biotin products are sold as hair and skin products, but the research is very thin on their benefits.
Sources: ncbi.nlm.nih.gov, ods.od.nih.gov, chrismasterjohnphd.com