B VITAMINS

B Vitamins are a group of water-soluble vitamins that are important for cell metabolism. There are 8 main vitamins present in this group. These include Vitamins B1, B2, B3, B5, B6, B7, B9 and B12. Mostly, all these vitamins are present in same foods. The combination of all these vitamins in a supplement is known as Vitamin B Complex. Whole grains are the best source of these vitamins except for vitamin B12 which is only present in animal foods.

Vitamin B1

Vitamin B1 or thiamine is especially important for the final metabolism of carbohydrates and few amino acids. Its deficiency causes the disease beriberi.

Central Nervous System (CNS) depends almost entirely on carbohydrates metabolism for its energy. Beriberi reduces the utilization of carbohydrates more than 50% to nervous system that can cause swelling of brain, emotional disturbances and irreversible loss of memory. Beriberi also weakens heart that produces irregular heartbeat and even heart failure in severe deficiency. The last major effect of beriberi is on GIT. Due to failure of getting enough energy from carbohydrates by the smooth muscles and glands of GIT, the problems of severe constipation, indigestion, anorexia etc. can produce.

Rich dietary sources of vitamin B1 are whole grains, sunflower seeds, cauliflower, oranges, potato, liver and eggs.

Recommended Daily Allowance (RDA) FOR Vitamin B1 is 1.4 mg. There’s no known toxicity from oral intake and therefore there’s no tolerable Upper Limit (UL) for this vitamin. 

Vitamin B2

Vitamin B2 or riboflavin is also important for several metabolic functions. Its deficiency produces symptoms like burning sensation of skin & eyes, digestive problems, cracks in the lips & corner of mouth, mental depression, headaches etc.

Good sources of vitamin B2 are milk, cheese, yogurt, leafy vegetables, liver, whole grains, almonds etc. RDA is 1.2 mg for adults while there’s no UL due to absence of toxic effects from dietary sources. 

Vitamin B3

Vitamin B3 or niacin plays an important role in the metabolism of glucose and fat. Its deficiency produces pellagra. Its symptoms include inflammation of skin, muscle weakness, insomnia, diarrhea, gastrointestinal hemorrhage, mental confusion, psychoses and permanent dementia.

Rich dietary sources are whole grains, legumes, chicken breast, beef, fish, dates, tomatoes etc. RDA is 16mg for men and 14 mg for women. UL is 35 mg/day. 

Vitamin B5

Vitamin B5 or Pantothenic Acid is important for the synthesis of Coenzyme A (CoA) while this coenzyme plays important function in the synthesis of antibodies, amino acids, cholesterol, fatty acids, steroid hormones, phospholipids etc.

Small amount of vitamin B5 can be produced in the body and also it is available in almost all foods. Due to these reasons, its deficiency is rare. Deficiency symptoms are acne and other skin problems.

Rich sources of this vitamin are whole grains, meat, eggs, royal jelly and yogurt. RDA is 5 mg for adult male and female. There’s no UL of vitamin B5 as no toxic effects have been seen so far. 

Vitamin B6

Vitamin B6 or Pyridoxine is important for the metabolism of amino acids, hemoglobin and lipids. Deficiency symptoms are microcytic anemia (decrease size of RBCs), high blood pressure, water retention, depression, skin inflammation etc.

Rich sources of vitamin B6 include fish, chicken, liver, soybeans, bananas, raisins, cauliflower, potatoes, blackstrap molasses etc.

RDA is 1.3 mg. UL is 100 mg/day. 

Vitamin B7

Vitamin B7 or Biotin is important for the metabolism of carbohydrates, lipids and protein. Deficiency can produce hair loss, inflammation of eye and skin. It can also cause neurological disorders and growth problems in children. Rich sources are green leafy vegetables, egg yolk (raw) and liver. 

Vitamin B9

Vitamin B9 or folic acid is needed for the formation of DNA. The two most important functions of folic acid are the promotion of growth and maturation of red blood cells. Its deficiency causes macrocytic anemia (large size of RBCs due to failure of their division). Other major deficiency symptoms include confusion, depression, diarrhea, low fertility in both men & women and pregnancy problems in women. People who consume alcohol are in danger of folic acid’s severe deficiency.

Main dietary sources of vitamin B9 include green leafy vegetables (especially spinach), fruits, nuts, grains and animal foods (especially liver).

RDA for adult is 400 micrograms while UL for people 19 and above is 1000 micrograms/day. Its toxicity can produce permanent damage to nervous system.

Vitamin B12

Vitamin B12 or cobalamin is slightly different from other B vitamins due to two reasons. First, it is only present in animal foods and secondly though it is a water-soluble vitamin like other B vitamins, it can be stored in liver in a bound form for a year if taken in higher amounts.

Vitamin B12 is important for metabolism of proteins, lipids & carbohydrates and for the production & maturation of red blood cells. It also acts as growth promoter.

Its deficiency produces macrocytic anemia, memory loss and psychosis. Absorption through gut decreases with age and elderly people are most likely to suffer from vitamin B12 deficiency.

Its food sources include fish, liver, meat, poultry, milk etc. RDA for adults is 2 micrograms/day while there’s no UL (upper limit) due to absence of toxic value.