B-Complex Vitamin Benefits & Side Effects
Vitamin B complex is actually a group of vitamins that include eight B vitamins. These B vitamins can be found in animal and plant sources, as well as in supplement form. They play a variety of roles in the body and provide numerous benefits. Taking too much of any vitamin can be dangerous and cause side effects.
What researchers used to think was a single vitamin — vitamin B — is a actually a group of eight different vitamins with distinct benefits and effects. Beside vitamin C, they are the only water-soluble vitamins, which means your body doesn't store excess. This means it's especially important to get adequate amounts of each vitamin through food — or supplements if necessary — to make sure you do not develop a deficiency. Because B vitamins are responsible for energy production, a deficiency can lead to fatigue, weakness, mental confusion and other side effects.
Benefits of B Vitamins
The B-complex vitamins are distinct nutrients with their own unique roles, but they overlap in some areas. For example, vitamins B-1, B-2, B-3 and biotin play a primary part in energy production, according to Michigan Medicine. Folic acid — or folate — and vitamin B-12 are required for cell division — the basis for all human life.
You need vitamin B-6, or pyroxidine, for amino acid metabolism. This is how protein from the food you eat gets broken down to its constituent amino acids, which your body then uses to make cells, muscles and other tissue. B-6 also aids in the formation of an iron-containing compound called heme. Vitamin B-12 acts as a cofactor for enzymes involved in protein and lipid metabolism, and in the synthesis of hemoglobin, according to the National Institutes of Health.
Biotin, another important B vitamin, transports carbon dioxide and aids in gluconeogenesis — a metabolic activity that results in the formation of glucose, which your body — especially your brain — uses for energy. Pantothenic acid, or B-5, plays a role in fatty acid and cholesterol metabolism, and choline, a compound similar to the B vitamins, is required for the structural integrity of cell membranes.
Read more: Foods Rich in Vitamin B-12 & Folate
Practical Uses of B Vitamins
People take B vitamins for various reasons. Some take megadoses of B vitamins — sometimes in the form of B-complex injection — with the goal of ameliorating everyday stress, combating fatigue and controlling food cravings. However according to University of Michigan Medicine, this likely only benefits people who are deficient.
Michigan Medicine rates B complex supplements as scientifically proven to aid in wound healing, and health-care providers sometimes prescribe high-potency B complex supplements for this purpose. Michigan also notes that B complex may be helpful for canker sores, as deficiency is often found in people with recurrent canker sores.
As for other benefits, Michigan Medicine reports that there is little or no scientific evidence to support efficacy of B-complex supplements to help with acne, anxiety, osteoporosis, PMS, indigestion and heartburn, along with a host of other conditions it is sometimes claimed to treat.
Side Effects of B-Complex
A vitamin B overdose is unlikely, especially if you get B vitamins from your diet. Because they are water soluble, any excess is excreted in your urine. Taking B vitamins in supplement form could have some minor side effects, including mild stomach upset and skin flushing. However, Web MD reports that these effects are temporary and should subside when your body gets used to the supplement. While many people don't experience serious side effects, it's wise to consult your doctor before taking a supplement of any kind.
Read more: Vegetarian Sources of B Vitamins