to healthy skin, muscles and general health.2 Vitamin B1, thiamine, helps carbohydrates to release energy; it also plays a part in making substances that are nerve response regulators. A major B1 deficiency can lead to ‘beriberi’, a disease that causes muscle and heart weaknesses.
Many foods contain B1, particularly liver, kidney, pork, yeast, eggs, green vegetables, cereals and fresh fruit. Some foods, like breakfast cereal, have thiamine added to them to ensure a sufficient daily supply.
Vitamin B2, or riboflavin, is a co-enzyme, or helper, needed in the break-down of fats, carbohydrates and especially the proteins needed by the respiratory system. It also helps to synthesize essential mucous material. A deficiency can lead to cracking of the lips (chellosis). It is found in meats, fish, egg yolks, liver, whole grains and dark green leafy vegetables. Remember Popeye in the cartoons? So eat spinach to give you strength! Popeye didn’t have cracked lips, but Bluto probably did when he was knocked out by Popeye, often because he had his eye on Olive Oyl, Popeye’s girlfriend!
Vitamin B3 releases energy from food. A lack of it can lead to ‘pellagra’, which looks like skin blisters when exposed to sunlight. In extreme cases it can affect the central nervous system and lead to depression and mental disturbances. Meat and liver products, nuts, vegetables, cereals, salmon and tuna all contain B3. In larger amounts it has been shown to reduce the cholesterol in the blood, although care has to be taken not to overdose since excess can cause liver damage.
Vitamin B5 or pantothenic acid, C9H17NO5, is involved in the break-down of fats and fatty acids. It is produced by intestinal bacteria in humans. Its deficiency is virtually unknown.Vitamin B6 or pyridoxine, C8H11NO3, is required in the uptake and metabolism of amino acids, fats and formation of red blood cells. A balanced meat, fruit and cereal diet produces enough B6 for healthy living. Deficiencies can lead to cracked skin at the corners of the mouth, dizziness, nausea, anaemia and kidney stones.
Vitamin B12, cobalamin or cyanocobaltamin, C63H88CoN14O14P, has the most complicated structure of the B vitamins. It contains one atom of cobalt in its molecule. It is required in minute amounts but without it the manufacture of proteins and red blood cells is affected. A diet which is deficient in liver, eggs, meat, fish or
milk can lead to pernicious anaemia. Vegetarians are often advised to take vitamin B12 supplements.
Other B vitamins include folic acid, B9, C19H19N7O6 (Figure 6.5), which is needed for effective formation of haemoglobin. Although it is found in a balanced diet, any food that has been stored or frozen loses its folic acid and so fresh foods are preferable. Pregnant women are often given folic acid supplements to help in make haemoglobin for themselves and their unborn child. Folic acid is quite a simple molecule that has been known for a number of years to be helpful in ensuring a healthy life and preventing heart attacks and some cancers. It is a water-soluble vitamin so it needs to be taken in constantly. It is present either as the acid or as one of its salts in green dark vegetables, fresh fruit, liver, Marmite and breakfast cereals.
However, it has recently come to light exactly what is affected by the absence or presence of folic acid. Any deficiencies of foliates can damage DNA synthesis and this can lead to many cell complications, including the formation of cancers.
Folic acid supplements seems to protect women from giving birth to babies with certain problems, including neural tube defects (NTD). NTD can cause the incomplete development of brain and spinal chord or the protective coverings around these organs. Spina bifida is an NTD defect and affects one baby in 1000.
This condition is caused when the spinal chord fails to become enclosed during the early stages of pregnancy. Expectant mothers are now routinely given folic acid supplements and also women wanting to become pregnant. However, as many as 50 % of pregnancies are unexpected or unplanned and so no pre-doses are possible and doses after the first month of pregnancy can be too late to prevent NTD.
Recent research has also noted that intake of foliates can reduce the occurrence of strokes and heart disease in middle-aged and older people. The action of the foliates in the blood reduces homocysteine levels (an amino acid). High levels of this are thought to damage coronary arteries by making harmful free radicals. These free radicals damage cell walls and cause the arteries to fur up, encouraging the bloodclotting platelet cells to gather together and cause a clot.
Low foliate levels and high homocysteine levels are found in the blood of older people, particularly those with Alzheimer’s disease. So here is another reason to have a healthy balanced, fruit/vegetable diet throughout your life. There are other Btype vitamins present in minute quantities whose exact role has yet to be fully
understood.
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