Vitamin H / B7 ( Biotin )
The Greek word for life “bios” gives the vitamin called biotin its name. Research has still to discover all the functional roles play by this vitamin in the human body, this is besides the fact that biotin’s essential role in many bio-chemical actions in the human body has been for over half a century. This vitamin is necessary to synthesize various fatty acids and a protein in the human body – it is also essential in the metabolism of carbohydrates from food. Biotin also additionally serves as an essential coenzyme in several enzyme reactions occurring in the human body. It is known that the thyroid and adrenal glands, the nervous system, the reproductive system, and our skin depend on an sufficient supply of this vitamin.
There is a general belief among some nutritionists that a deficiency in biotin can only occur if the biotin in the body is destroyed due to the actions of a chemical antagonist – for example, the proteins found in raw egg whites. At the same time, evidence from clinical research shows that quite large numbers of individuals do possess very low levels of biotin in the blood at any one time. Such people include elderly individuals, all athletes and sportsmen, women in a term of pregnancy, long term alcoholics as well as people affected by achlorhydria – this is the complete absence of hydrochloric acid in the stomach of the person. The biotin levels in the blood of pregnant women, for example, begins at far lower levels compared to other adults, the levels of this vitamin keep on decreasing as the term of pregnancy progresses. At the same time, it is difficult to accurately measure the biotin found in the mother’s milk after the birth of a baby for at least four days-the levels become higher after this period has elapsed. The levels of biotin in the blood than varies from one individual to the other. Lower than normal levels of biotin are also normally observed in individuals affected by liver disease. The level of biotin in the blood plasma also tends to drop below normal levels in children who have suffered from burns and scald injuries.
Biotin is mainly antagonized by a protein component of raw egg white called avidin. The protein avidin binds to biotin and closes all the pathways for the vitamin and this makes the vitamin unavailable for utilization at the cellular level.
The use of drugs like antibiotics can bring on a deficiency of biotin in the body. Biotin is normally absorbed in the bloodstream and many clinical researchers are of the opinion that the bacteria that are usually found in the intestines can synthesize biotin and make it available for absorption. These beneficial bacteria may be eliminated by long use of antibiotics, thus shutting off a potentially vital supply of biotin to the body.
A wide variety of supplemental forms of biotin are available in the market. These range in doses from a few micrograms to several hundred micrograms per dose.
The liver and all other organ meats make for the best dietary sources of biotin; other good sources are the yolk of eggs, peanuts, filberts and mushrooms, fruits like bananas, plants like soy and cauliflower. Biotin is also found in good quantities in all kinds of whole grains commonly seen in the diet. Most of the biotin is eliminated during the processing and refining of cereals and grains – including white rice and flour, as fortification is commonly left undone, the level of biotin in these foods may be very low.
The proper metabolization of the vitamin can be severely affected by certain very rare and inborn diseases – this leads to a rapid depletion of the stores of biotin in the body. Even in individuals who consume a diet very low in this B vitamin, the presence of a dietary deficiency of biotin is quite rare. A biotin deficiency can nonetheless develop in the body if someone eats large amounts of raw egg whites as a part of the diet – this is because, the protein avidin found in the raw egg white inhibits the proper absorption of biotin from the gut. This problem does not occur with cooked eggs. The synthesis of biotin in the intestines can also be adversely affected by the long term use of antibiotic drugs; this increases the risk of deficiency symptoms developing in the person. Symptoms include dermatitis, chronic depression, hair loss, anemia, and spells of nausea. A biotin deficiency can also come about by the long term use of some types of anti-seizure medications. There are reports of a generally low biotin status amongst long term alcoholics, in individuals affected by inflammatory bowel disease and those people affected by diseases of the stomach. It is still unclear as to how much effect a long supplemental regimen of biotin will do for these individuals. Birth defects are also known to be induced by a deficiency of biotin in animals.
There is no RDA for biotin and the ideal rate of intake for this vitamin remains a mystery. At the same time, deficiency symptoms can usually be prevented by even the amount of biotin present in most diets, especially when this source of vitamin is combined with the intestinal production of biotin – these two sources of biotin appear to be adequate for the average person. The adequate level of intake for adults of biotin that has been estimated by researchers is about 30 mcg of the vitamin a day. The amount of biotin that is usually available to a person consuming a typical western diet is estimated to be about 30-70 mcg daily. As the vitamin aids in preventing the onset of diabetic neuropathy and lowers blood glucose levels, larger amounts of biotin at doses of 8-16 mg daily can be very supportive for diabetics – such people will benefit from a supplemental regimen of biotin. In one clinical trail, intakes of biotin at amounts of 2.5 mg daily resulted in strengthened fingernails of two-thirds of the volunteers with brittle nails.
Side effects and cautions
No toxicity has been associated with the use of high doses of biotin, and normally excess biotin is excreted in the urine. There are no known side effects. The vitamin biotin works well with some of the other B vitamins, including the folic acid, the vitamin B5 or pantothenic acid as well as the vitamin B12 or cobalamin. The need for people using supplements of biotin to also supplement with these vitamins is however, not supported by any solid evidence. Biotin supplements have also been reported to lessen symptoms of pantothenic acid or zinc deficiency, even though individuals who are affected by these deficiencies must make sure to supplement with the nutrients that are found at low levels in the body. Though very little is known about the real significance of these interactions, researchers think that the vitamin biotin and alpha lipoic acid could compete with each other in the body for the absorption or uptake into cells – the nature of such chemical interactions are still to be investigated.