Vitamin B complex: functions

Vitamin B complex includes Vitamin B1 (Thiamine), Vitamin B2 (Riboflavin), Vitamin B3 (Niacin), Vitamin B5 (Pantothenic acid), Vitamin B6 (Pyridoxine, Pyridoxal, Pyridoxamine), Vitamin B7 (Biotin), Vitamin B9 (Folic Acid or Folate) and Vitamin B12 (Cobalamins)

These vitamins are water soluble vitamins, therefore, they are not stored in the body and their reserve in the body lasts only a few days; dietary intake has to provide for these vitamins regularly

In general, Vitamins of  B complex are needed in energy metabolism (generation of energy from food that we eat, such as carbs, fat etc.) and some, such as folate and vitamin B12, have other very important functions in cell division and therefore growth, red blood cell synthesis and maintenance of nervous system in the body

Vitamin B complex deficiency in Indians

  • Countrywide surveys conducted by the National Nutrition Monitoring Bureau (NNNB) showed that only 40 % households meet 100 % of the RDA for Thiamine (vitamin B1), and 29% consumed less than 60% of the RDA
  • Dietary deficiency of riboflavin is rampant in India. Recent NNMB surveys show that only about 13% households meet the dietary requirement of riboflavin and more than 60% get less than 60%
  • Diet surveys from India show that the average intake of niacin is lower than the RDA and especially among heavy rice eaters
  • Vitamin B6 Deficiency is documented in Indian populations, especially in pregnant ladies and those on OCPs (oral contraceptive pills), although limited data is available
  • Reports from all parts of the country show that vitamin B 12 deficiency could be present in more than 30% of Indians
  • Indians consume folate in lower quantities than the recommended

People at risk for deficiency of vitamins of B complex

  • Vitamin B12 is found only in food of animal origin: meat, fish, eggs , milk and dairy products, therefore vegetarians, with not enough milk intake, or vegans are at risk of vitamin B12 deficiency.
  • In the elderly, deficiency can result in irreversible damage of neurological function therefore checking for vitamin B12 deficiency in people at risk is very important
  • Folate deficiency is common in women of childbearing age and in adolescent girls and can cause serious diseases in the unborn child. Therefore, a supplementation of 400 mcg folate is recommended in women planning to have a baby and folate rich diet is recommended for all girls and women
  • People who eat milled rice heavily are at risk for thiamine and niacin (vitamin B1 and B3) deficiency and people who drink a lot of alcohol are also at high risk of thiamine deficiency

Signs and symptoms of deficiency of B complex vitamins

The diseases associated with severe deficiency of vitamins of B complex, such as Beri-Beri, Pellagra, Megaloblastic anemia etc. are not very common in affluent people, but subclinical deficiency, which gives rise to vague complaints such as fatigue, tiredness, numbness of feet, skin and mouth sores/lesions, subtle intestinal upset etc. , is common but often ignored

To know more about deficiency signs and symptoms and who is at risk go to: ‘Supplements: should you be taking any?’

Rich dietary sources of B complex vitamins

Vitamin B1: Whole grain cereals, nuts, legumes, green leafy vegetables, organ meats, pork, liver and eggs are rich sources of Thiamine

Vitamin B2: Flesh foods, poultry, dairy products, legumes, nuts and green leafy vegetables are rich sources of riboflavin

Vitamin B3: Whole grain cereals are good sources of niacin but not polished rice and jowar, both niacin and tryptophan are found richly in food of animal origin

Vitamin B6: Meat, fish, poultry, pulses, nuts and wheat are known to be rich sources of the vitamin, while other cereals, potato (starchy vegetables) and non citrus fruits are moderate sources

Folate: Good food sources of folate include broccoli, Brussels sprouts, asparagus, peas, chickpeas and brown rice. Green leafy vegetables, fruits and fruit juices (especially oranges and orange juice), nuts, yeast, cereals and pulses are moderate sources

Vitamin B12: Foods of animal origin: meats, organs, eggs and milk are the only source of vitamin B12. Vitamin B12 is present in food of plant origin only by unhygienic practices and contamination with microbes!

CHECK OUT: Our references for recommendations on diet