PROTEIN IN VEGET ARIAN DIETS

The term ‘vegetarian ‘ covers a wide range of eating habits and, in order to analyse the nutritional content, it is important to differentiate between the types. V egetarians exclude meat, fısh and poultry from their diet although most eat eggs anddairy pro- duce and are sometimes known as lacto-vegetarians.

Vegans or strict vegetarians do not eat any animal products and they must take special care when planning their diet to ensure that they eat a wide variety of wholewheat cereals, pulses, nuts and legumes (podded plants such as peas and beans). Soya bean protein is comparable with meat protein, so is valuable to vegans.

VITAMINS

Vitamins, which are vital for proper body functioning, can be divided into two different types- the fat soluble and the water soluble ones. Vitamins A, D, E and K dissolve in fats and are mostly found in foods which contain fat. They are stored in the liver in amounts large enough to last for several months. The water soluble vitamins, C and the B complex, dissolve in water and cannot be stored in the body in large quantities. Small amounts are found in body cells and added together they form what nutritionists call the vitamin pool. Once the pool is full or saturated, any excess is simply excreted from the body .As the vitamins are used up, the pool needs to be topped up.

The amounts of vitamins needed by the body are tiny .Most people in Britain obtain all the vitamins they need from food, provided their diet is varied enough. Those who believe they have special needs should ask their doctor for advice. If extra vitamins are recommended, a multi-vitamin tablet should fulfıl the need, but do not exceed the recommended dose. The body is a fınely-tuned machine and taking large doses of fat soluble vitamins can upset its chemical balance and cause illness and even death -large amounts of vitamins A and D stored in the body can have fatal consequences.

However , it is highly unlikely that toxic amounts of vitamins come from food, unless unnatural quantities of, for example, carrot juice or liver are consumed to excess. Most problems occur when high dosage vitamin tablets are regularly taken. For instance, although excess amounts of water soluble vitamins are generally eliminated from the body in the urine, taking large amounts of vitamin C over a period of time has been linked with kidney stones and ‘rebound sturvey’. In the case of the latter, the body gets ‘used to high doses of the vitamin and reacts by developing the defıciency disease when vitamin C intake levels return to normal.

Vitamins and minerals (see page 14) often work together , one complementing the work of the other . Iron absorption can be increased signifıcantly if vitamin C is present in the body , so a fresh orange eaten after liver ensures that the iron in the liver is well absorbed.

Some vitamins are easily lost or destroyed by bad storage, preparation or cooking. If fruit and vegetables are cooked for too long, most of their vitamin C is destroyed. If milk is left on the door- step, sunlight will reduce its riboflavin (vitamin B2) content (see page 14 ).

Buy fresh fruit and vegetables in prime con- dition and store in a cool place. Prepare them just before they are needed, do not leave them soaking in water. To keep vitamin loss to a minimum, cook in a small amount of water for as short a time as possible, or steam them. Wherever possible, eat raw fruit and vegetables which then retain all their vitamins.

Folic acid (folacin) is needed to produce healthy red blood cells. Defıciency is being increasingly recognised in pregnant women, old people and Asian immigrants, who may need supplements. Good food sources include liver, green leafy vege- tables, pulses, bread, oranges and bananas. Other fruit, meat and dairy products contain little.

Pantothenic acid is needed for all tissue growth as it plays a large part in releasing energy from fats and carbohydrates. It is found in a wide variety of

foods, particularly animal produce, cereals and legumes.

Vitamin A (retinol) is needed for growth, good vision in dim light, healthy skin and surface tissues, especially those that secrete mucus. Vitamin A is the vitamin in its active form and is known as retinol. Provitamin A, vitamin A precursors or caratenoids are substances which the body can tum into vitamin A. These are found in animal foods, dairy products and vegetables. Good sources include offal, green leafy vegetables, yellow and orange-coloured fruit and vegetables, e.g. car- rots, tomatoes, apricots, peaches and Cantaloupe melons, butter and margarine.

Vitamİn B was originally thought to be one vitamin, but has tumed out to be a complex of substances. There are at present thought to be about eight vitamins in the B group and they often appear in the same foods. The three best known are thiamin (vitamin Bl), riboflavin (vitamin B2) and niacin or nicotinic acid (which used to be referred to as vitamin B3). These three are always known by their chemical names, while most of the others are known by their numbers.

Thiamine (Bl) helps the body release energy from carbohydrates. Good sources include milk, offal, eggs, vegetables, fruit, wholegrain and fortifıed cereals-including bread and breakfast cereals- pulses and nuts.

Ribofiavin (B2) is also vital for the release of energy from food. About one third of our daily intake comes from milk. Other good sources in- clude offal, eggs, cheese and yeast extract.

Niacin helps in the conversion of food to energy . The main sources are meat, fısh, fortifıed breakfast cereals, vegetables and yeast extract.

Vitamin B6 (pyridoxine) helps the body utilise protein and contributes to the formation of haemo- globin for red blood cells. it is found in a wide range of foods including meat, fısh, eggs, wholegrain cereals, some vegetables, pulses and yeast extract.

Vitamin B12 (cyanocobalamin) is essential for the production of healthy red blood cells. Defıciency leads to a type of anaemia. The only people at risk of not getting enough of this vitamin are vegans, as it is found only in animal foods. Useful sources include liver, meat, eggs, fısh, milk and cheese.

Vitamin B13 (orotic acid) is littie known; its function and its defıciency effects are not known.

Biotin also belongs to the B complex. it is made by bacteria in the intestine and is also fouhd in offal, egg yolk, vegetables, cereals, fruit and nuts.

Vitamin C (ascorbic aC:id) is needed to keep the connective tissue between cells healthy .Vitamin C

is found almost exclusively in fresh fruit and vegetables, including potatoes. A glass of orange juice will supply a day’s requirements. Despite the popular belief that vitamin C will prevent or cure colds, the evidence is not conclusive,

Vitamin D (cholecalciferol) is needed for the growth and formation of bones and teeth as it helps in the absorption of calcium and controls the amount that is retained. Children, pregnant women and lactating women have particularly high require- ments, while elderly people and Asian women and children may be at risk of deficiency .

Vitamin D is obtained by the action of sunlight on a substance in the skin. It is also found in a few sources such as some dairy products, some fish and margarine. Most of the body’s supply comes from sunlight.

Vitamin E can be found in different forms under the names tocopherols and tototrienols-tocopherols is the most common name. It is thought to be essential for muscular health ‘and blood circulation. Rich sources include wheatgerm, vegetable oils, some vegetables and nuts.

Vitamin K is needed for the normal clotting of the blood, It is found in green and some other vege- tables, cereals and pulses. It is also made by bacteria in the intestines.

MıNERALS

These cannot be manufactured by the body and must be obtained from food, At present, 15 minerals have been identified as being essential to health and others are still under investigation. The majority of people obtain enough minerals pro- vided a good variety of food is eaten.

Calcium is essential for the growth and develop- ment of bones, teeth and tissues. It is also İleeded for muscle contraction, nerve functioning, the action of several enzymes and for the normal clotting ofblood. Calciumis found in milk, yogurt, cheese (including reduced and low fat varieties), white or brown bread and flour (which are fortified with calcium), eggs and green vegetables, It is also present in the soft bones of canned fish and in small quantities in many other foods,

Iron is used to make the haemoglobin in red blood cells and is stored in the muscles and liver .Haemo- globin carries oxygen to supply all the body’s cells and a shortage leads to anaemia. Iron deficiency is fairly common in Britain, particularly in women of child bearing age since iron requirements are increased by menstrualloss and pregnancy .

The body can adapt to increased needs by increasing its absorption from the intestine, but

some women still need to be prescribed iron tablets or supplements. Iron is found in meat (particularly liver), some fısh, cereals, pulses and vegetables. The iron in vegetable foods is less well absorbed than the iron in animal foods, but vitamin C increases the absorption of iron from all foods.

Magnesium is concentrated in the bones and pro- vides strength for them. Minute amounts are also found in body cells. It is necessary for the function- ing of some enzymes and also plays a part in breaking down foods to release energy .It is found in cocoa, some nuts and green vegetables.

Phosphorous is mainly laid down in the skeleton with calcium. The rest interacts with some B com- plex vitamins to release energy from foods and is present in small quantities in many body cells. It is found in a wide variety of foods.

Potassium, together with sodium (see Salt on page 12) plays a vital part in the functioning of nerves and in determining blood pressure. It is found in many foods, particularly fruit, vegetables, cereals, eggs, cheese, fısh and some meats, such as offal beef and pork.

Sodium and Chlorine (see Salt on page 12).

Sulphur is found in minute quantities in every cell in the body. Al1 protein foods contain sulphur, so there is no danger of defıciency .

Trace elements are mineral substances present in the body in very smal1 amounts. With the varied diet eaten in Britain, there is unlikely to be a defıciency of any of the important ones known so far. Considerable work is being done on trace elements and new ones may wel1 yet emerge. Those recognised as being essential for health include cobalt, copper , chromiuIİl, fluoride, iodine, manganese and zinc.

GUIDELINES FOR HEALTHY EATING

Obviously no-one needs to eat a perfectly balanced diet every day .The odd junk meal or day of snacks will even itself out over a week of varied eating. Fresh foods which have not undergone any processing are obviously better than packaged versions, but make sure that they really are fresh. Canned, dried and frozen foods can be just as good as fresh.

Read the list of ingredients on manufactured food packaging, so you can avoid those foods con- taining excessive amounts of sugar, salt or undesir- able additives such as colouring or reservatives.

PROTEIN IN VEGET ARIAN DIETS