Group B vitamins include thiamin (vitamin B1), riboflavin (vitamin B2), niacin, biotin, pantothenic acid, pyridoxin (vitamin B6), folic acid, and cobalamin (vitamin B12).
Most of the vitamins of group B participate in the body in the metabolism of energy nutrients, i.e. carbohydrates, proteins and fats. Evidence of influence on the functioning of the nervous system is available for thiamin, niacin and vitamin B6. Vitamins B are water-soluble, which means they do not accumulate in the body, but any excess vitamins are removed from the body, primarily through the kidneys in urine. An exception to this, however, is vitamin B12, which accumulates in the body. Due to their water-solubility, regular and continuous intake of vitamins B from nutrition is essential.
Deficiency of vitamins B is rare, as they are obtained from the commonly used basic nutrients, such as milk and milk products, meat, eggs, cereals and vegetables. Deficiency of vitamins B is usually caused by poor nutritional state, which is why it is mainly found in alcohol abusers and in persons following a strict vegan diet.
Excessive intake of vitamins B is rare and impossible from purely nutritional sources. Moreover, most vitamins B are safe also in high daily doses. On the other hand, there is very little knowledge available about the symptoms caused by excessive intake of vitamins B in humans.
A can of energy drink will often provide the required daily intake of vitamins B, or clearly more than that. Below are some examples of vitamins B added in energy drinks per 100 ml, with the percentage of this content of the recommended daily intake given in the brackets:
- Vitamin B12 1-2 micrograms (100-200%)
- Niacin 8 mg (44%)
- Pantothenic acid 2 mg (33%)
- Riboflavin 0.56-0.6 mg (35-38%)
- Vitamin B6 1.8-2 mg (90-100%)
Although excessive intake of most vitamins B has not been established to be associated with any detrimental effects, it should be borne in mind that there is no research-based evidence of the influence of long-term exposure. Any detrimental effects could at individual and population level remain uncovered for several years.