The vitamin B complex refers to a group of water-soluble vitamins that in general play an essential role in the metabolic processes of living cells involved in the oxidation of foods and production of energy. The complex was once thought to be a single nutrient, but in time researchers identified eight essential B vitamins, the term “essential” in this context meaning the vitamins are required for regular metabolic functions but cannot be synthesized by the body (or at least not in adequate amounts) and thus must be obtained from dietary sources. The vitamins are grouped into one complex because they work in tandem in several ways, complementing each other and the vitamins also have common food sources. However, it should be noted that each of the eight B vitamins—given distinguishing numbers although they also have chemical names—has its own particular role to play as well.
First, let's consider some of the ways the entire complex—or most of the eight in any given situation—maintains and modulates biological mechanisms in the body. One of its important roles is to maintain optimal neurological functioning of the brain by facilitating the work of hormones and neurotransmitters. This is related to mental functions including cognitive reasoning and memory retention. It appears the complex promotes mental well-being, helping to decrease the risk of developing depression, anxiety, age-related memory decline and other mental diseases of the elderly.
In an entirely different role, the vitamin B complex aids in keeping the digestive system healthy by stimulating gastric juices in the stomach. As well, specific vitamins in the complex help with the absorption of nutrients from the tract. A high serum concentration of B vitamins—which indicates adequate ingestion from dietary sources—is considered protection against breast, liver and lung cancers by neutralizing free radicals and toxins in the blood.
Nearly all B vitamins are required for the growth and development of superficial layers of the skin. Lack of sufficient intake leads to dry scaly skin including dandruff, graying of hair (although other factors play into this) and other premature signs of aging. Vitamin B6 (pyridoxine) is pulled out as particularly important for the management of psoriasis (an inflammatory skin diseases that produces plaques of scaly skin), acne, and seborrhea dermatitis (a skin condition that usually affects the scalp).
Some B vitamins are better known by their official names than numbers. For example, most people have heard of thiamine, riboflavin and niacin (B vitamins 1, 2 and 3 respectively). Thiamine is sometimes called the anti-stress vitamin for its ability to protect the immune system while riboflavin works as an antioxidant, helping to fight free radicals, and plays a significant role in red blood cell production. Niacin's main role is to boost HDL (good) cholesterol in the blood which has the effect of decreasing LDL (bad) cholesterol.
Vitamin B5 (pantothenic acid) is known for its role in breaking down fats and carbohydrates for energy. In addition to its role in managing skin conditions (noted above), Vitamin B6 is a major player in mood and sleep patterns because it helps the body produce hormones such as serotonin, melatonin and norepinephrine. Vitamin B7 (biotin) is “the beauty vitamin” because of its association with maintaining healthy hair, skin and nails. Along with its cousin vitamin B9 (folate or folic acid), it is vital for normal growth of the baby during pregnancy and preventing neurological birth defects.
Vitamin B12 (cobalamin) affects the development and maintenance of red blood cells and normal myelination (covering) of nerve cells. It also assists with the production of DNA , RNA and neurotransmitters.
It is obvious that B vitamins play a significant role in many ways to keep the body in optimum health, having an impact in everything from digestion and energy production to mental and emotional well-being. It is extremely fortunate that people ingesting a well-balanced diet should have no problem with taking in adequate amounts. Small quantities are found in every food group with particularly good or excellent sources being green leafy vegetables, whole grain breads and cereals (containing the germ and bran), red meats, legumes, eggs, milk and other dairy products, seeds and nuts.
It should be noted, however, that in certain situations a supplement might be necessary. One is in the case of a pregnant woman (or one trying to conceive) whose diet may be low in dark green leafy vegetables, legumes and root vegetables (all especially good sources of folate). If unsure, you should talk to your physician. In addition, vegetarians who shun all meat and animal products should check into taking a vitamin B12 supplement since this vitamin is available only from meat sources. A vitamin B complex supplement is available, but it is wise to consult your physician before ingesting.
Since B vitamins are water-soluble, there is little danger of toxicity from moderate intakes—excess amounts will wash out of the body in the urine.