There are eight key B vitamins the body needs to keep healthy. The B vitamins are water soluble and cannot be stored in the body for any length of time. This means we need a daily supply of these B vitamins in the food we eat.
Which foods contain the B vitamins?
Meat, fish, eggs, milk, cheese, yeast extract and fortified breakfast cereals are a good source of B vitamins, so too are wholegrains, pulses, nuts, dried and fresh fruit and vegetables.
In the UK, white and brown bread flour are fortified by law with two B vitamins – thiamine (vitamin B1) and niacin (vitamin B3).
One thing to note is that vitamin B12 is only found in food of animal origin so any one eating a vegan diet needs to supplement their diet with vitamin B12. Oat Drink is fortified with Vitamin B12.
Vitamin B6 and vitamin B7 are present in food but can also be made in the body by gut flora.
What are the eight key B vitamins?
- Thiamin (vitamin B1)
- Riboflvin (vitamin B2)
- Niacin (vitamin B3)
- Pantothenic acid
- Pyridoxine (vitamin B6
- Biotin (vitamin B7)
- Folic acid
- Vitamin B12
Just to remind you….
Vitamins are a group of organic compounds which are essential for normal growth and health. They are required in small quantities in the food we eat because they cannot usually be made by the body.
What do B vitamins do in the body?
- Thiamin (vitamin B1) is needed to release energy from carbohydrate. How much thiamine you need is related to the amount of energy you expend. Thiamin is also involved in the normal function the nervous system and other tissues, such as skeletal muscles and the heart. Deficiency of thiamin causes a disease of the nervous system called beri-beri. This became a public health issue in the Far East in the nineteenth century with the introduction of highly milled (polished) rice. Beriberi is now rare, but it remains a problem in some parts of the world where rice is the staple food.
- Riboflavin (vitamin B2) is needed to release energy from protein, carbohydrate and fat. It is also involved in how the body transports and uses iron in the body. Mucous membranes that line the nose, throat and gut also require riboflavin and so does skin. Recent UK dietary surveys have shown young women and women over 65 have low intakes of this vitamin.
- Niacin (vitamin B3) is also required for the release of energy from food and to keep the skin and mucous membranes healthy. It can be made in the body from an amino acid called tryptophan which is plentiful in a normal diet.
Deficiency of niacin results in the disease pellagra. The main symptom is sun-sensitive skin producing effects rather like severe sunburn. Pellagra is now rare but was a major public health problem in the early part of the last century where maize forms the staple diet in some countries. Maize contains little tryptophan and the niacin that is present could not be digested.
- Pantothenic acid is required for the release of energy from food. You should be able to get the amount of niacin you need by eating a varied and balanced diet. If you take niacin supplements, don't take too much as this might be harmful.
- Pyridoxine (vitamin B6) helps to breakdown protein, form red blood cells and transport iron. Vitamin B6, together with folate and vitamin B12, is required for maintenance of normal blood homocysteine levels. Raised homocysteine is a risk factor for cardiovascular disease. Vitamin B6 can be toxic if taken in high doses and causes sensory nerve damage.
- Biotin (vitamin B7) is needed in very small amounts to help the body break down fat. The bacteria that live naturally in your bowel are able to make biotin, so it's not clear if you need any additional biotin from the diet. Biotin is also found in a wide range of foods, but only at very low levels.
- Folic acid helps the body form healthy red blood cells and reduces the risk of central neural tube defects, such as spina bifida, in unborn babies. A lack of folic acid could lead to a type of anaemia where the red blood cells do not mature properly. A deficiency can lead to symptoms of insomnia, depression, forgetfulness and irritability.
- Cyanocobalamin (vitamin B12) is involved in making red blood cells, keeping the nervous system healthy and releasing energy from food. A lack of vitamin B12 could lead to vitamin B12 deficiency anaemia.
Do I need to take supplements of the B vitamins?
Most people get all the B vitamins they need from a normal balanced diet and do not need to take supplements apart from the following two groups.
If you are planning to have a baby the Department of Health recommends that folic acid supplements should be taken.
Sources of vitamin B12 are limited for vegans who do not eat any animal foods therefore a vitamin B12 supplement may be needed. Some foods such as plant milks such as Oat Drink, yeast extracts and fortified breakfast cereals contain vitamin B12.
For more information on B vitamins see www.nhs.uk