- Vitamins for body health! Boost your immune system
- Vitamins for body health! Vitamin A
- Vitamins for body health! The B Group Vitamins
- Vitamins for body health! Vitamin C
- Vitamin D
Vitamins for body health! Boost your immune system | Everyone knows that we all need vitamins, but what exactly are they? In this section we’re going to have a whirlwind introduction to the wonderful world of vitamins, and, as before, focus particularly on those that may not be so plentiful in the average person’s diet.
The importance of vitamins wasn’t realized until the beginning of the twentieth century, when scientists began to find that tiny amounts of certain organic substances were essential to health. They called these organic substances vitamins, coming from the Latin word vita’ (meaning life) coupled with the word ‘amine since they mistakenly believed that all vitamins contained amino acids (they don’t).
Vitamins for body health! Boost your immune system
Since they discovered that vitamins were either soluble in fat or in water, they also wrongly assumed that there were only two basic vitamins – and these they called Vitamin A (being fat soluble) and Vitamin B (being water soluble).
We now know that there are well over twenty different vitamins, but they can still be divided into fat- or water-soluble types. Their basic work in the human body seems to be as the constituents of enzymes, which help to regulate our metabolism, converting fat and carbohydrate into energy, and helping us to make new tissue and bone.
A Cook’s Tour of the World of Vitamins.
Vitamins are called micro-nutrients, since the body only needs minute (but essential) quantities of them in the diet. Many people seem to have an almost magical faith in the power of vitamins, which the pill manufacturers are not slow to exploit. However, taking megadoses of synthetic vitamins is never preferable to getting a good supply of natural vitamins from a well-balanced diet.
Vitamins work in complex and inter-related ways in the human body and they never work alone. A synthetic vitamin pill can never replicate the delicate relationship that exists between different vitamins in nature, and relying on such pills may actually be harmful.
Large doses of fat-soluble vitamins (such as A, D, E and K) will tend to accumulate in the body and may eventually prove toxic Water soluble vitamins are much less toxic in large doses, but still may produce symptoms of overdose. As always, it’s a question of getting the balance right!
Vitamins for body health! Vitamin A
Vitamin A (retinol) is formed in the healthy human body from carotene, which is a substance that gives a yellow or orange colour to plants Fruits or vegetables of these colours are therefore likely to be good vitamin A sources. Diabetics have problems in converting carotene into vitamin A, and should therefore be careful to ensure that they are not retinol deficient.
Vitamin A is stored in our livers and its functions include helping new cells to grow, as well as the more well-known one of aiding night vision (this aspect of vitamin A became publicised in World War Two, when the British Government tried to conceal their development of radar by attributing the success of their bombing missions over Germanyto the high doses of vitamin A that the crews were taking).
It has also been used externally to treat cases of acne, impetigo, boils, carbuncles, ulcers, and to promote the healing of wounds. Too much vitamin A will cause toxic symptoms, which may include headaches, sickness, irritability, and in severe cases) growth retardation in children. On the other hand, a deficiency of Vitamin A in the diet will eventually cause a general weakening and increased susceptibility to many kinds of infection probably including cancers.
It is thought that this happens when our cell walls (which vitamin A gives strength and protection to) become more susceptible to invading bacteria. In some countries, vitamin A deficiency can be a serious problem. It has been estimated that as many as 80.000 children go blind every year due to lack of vitamin A, and about half of them will die as a direct result.
Cooked vegetables are actually higher in usable vitamin A than raw ones, because the plant cell membranes are destroyed during cooking, thus making more carotene available for our bodies to convert to vitamin A proper (retinol). However, high-temperature cooking will tend to destroy or degrade it.
Vitamins for body health! Measuring the amount of vitamin A
Measuring the amount of vitamin A in foods can be somewhat complicated, since some sort of allowance has to be made for the carotene-retinol conversion process carried out by the body. The Recommended Daily Allowances give a retinol-equivalent figure for vitamin A in micrograms. This measures the final amount of vitamin A that ends up in our bodies coming from whatever source.
- For Plant Food Sources: devide the amount of B-carotene measured in us by ten to calculate the retinol equivalent.
- For Animal Food Sources: multiply the amount of retinol measured in lus by 0.3 to calculate the retinol equivalent.
- Where vitamin A is measured in micrograms of B-carotene, this figure should be divided by six to calculate the retinol equivalent (except for milk, when it should be divided by two).
Vitamin A is not found in all foods by any means, so here is a list of some of the better sources, together with the amount of vitamin A they contain, stated as retinol equivalents. The quantities of each food have been standardized to 100 grams, to enable a quick comparison to be made:
Vitamin A content:
Margarine (fortified) 900
Mustard Greens (cooked) 820
Cress (cooked) 770
Endive (raw) 330
Pimentos (tinned) 230
Mela (ogen/canteloupe) 175
Peas (raw) 64
Green Pepper (raw) 43
Finally, one interesting source of Vitamin A is the spice paprika, which contains 127 micrograms (retinol equivalent) in just one teaspoonful!
Vitamins for body health! The B Group Vitamins
Meat is not an only vital source of B vitamins. In fact, it’s not a vital source of anything. There is no nutrient contained in meat that cannot be obtained from other sources.
The B group vitamins, however, are vital to human well-being, and everyone ought for their own sakes, to know what they are and where to find them. This sort of knowledge gives you power — the power to refuse to be exploited or manipulated by commercial interests when they try to sell you their products by telling ‘little white lies!
So what are the B group vitamins? Chemically, they are all rather different, but they do have certain things in common. They are all soluble in water and so pass through the body quite quickly (this means we need a regular source of them in our diet).
They are produced from bacteria, yeasts and moulds, and so tend to naturally occur together in nature. Most of them can therefore be found in yeast products (brewer’s yeast, or yeast extracts), and wholegrain cereals are another good source.
Requirment of B Vitamin
We need B group vitamins to help us convert the carbohydrate in our diet into usable energy, and they also help the nervous system to function properly. We need more B vitamins during times of infection, stress or high activity, and heavy alcohol and coffee drinkers also need a higher than normal intake. A typically highly
processed ‘junk food’ diet does not contain an adequate level of these vitamins, and, if this applies to you, this is one more good reason to take a greater interest in your food habits!
A deficiency of these vitamins may lead to irritability, depression, and in extreme cases even suicide. Grey or falling hair, insomnia, poor appetite and constipation are more signs of possible deficiency.
Vitamins for body health! Foods with B Vitamin
Vitamin B, (Thiamin) is fairly plentifully supplied in many natural food sources. The Recommended Daily Allowances (R.D.A) for Thiamin range from 0.3mg (for infants under 1 year) to 1.4mg (for very active males). As a rule, the more active you are, the more thiamin you need, and the more carbohydrate you take in (this includes alcohol) the more thiamin you need.
Most of this can be supplied by a single tablespoonful (8 grams) of brewer’s yeast, which contains 1.2mg of thiamin. Other good sources include millet (0.85mg in half a cup, dry), peas (0.45mg in one cup, cooked). broccoli (0.48mg in 3 stalks, cooked), wheat germ (1.omg in one cup), and sunflower seeds (1.42mg in half a cup).
It is not known whether there are any toxic effects in cases of overdose. Vitarnin B2 (Riboflavin) is also quite widely distributed in foods, although many foods contain very small amounts. Lack of riboflavin is believed to be one of the most common vitamin deficiencies in the West.
About a third of the average intake of riboflavin in this country is provided by milk, and since riboflavin can be destroyed by ultra-violet light, milk should not be left exposed to sunlight. Deficiency of riboflavin is believed to lead to a lack of stamina and to retard human growth, and may result in certain visual problems, including cataracts. Some good sources are given in the Calculator.
Vitamins for body health! Some good sources are
Pyridoxine is found in whole grains and brewer’s yeast. Some good sources are: avocado (0.84g in one average); skim milk (O.Img in one cup): yeast extract (0.24mg in one tablespoon); wheat germ (1.img in one cup, toastedi: orange juice (Img in one unsweetened cup): raisins (0.4 in one cup); roasted peanuts (0.5mg in one cup); sunflower seeds (1.8mg in one cup); walnuts (0.73mg in one cup): cauliflower (0.22mg in one cup, cooked or raw); tomato juice (0.37mg in one cup); broccoli (0.89mg in 3 stalks raw): and banana (0.61mg in one average),
Vitamin B12 is the only B vitamin that does not occur in plants (it does occur in some fermented plant foods, since it is produced by a micro-organism, like a mould). The suggested daily intake is 3 micrograms, and 4 micrograms for pregnant or lactating women.
This can be easily supplied as follows: skim milk (Imcg in one cup): soya milk (4mcg in one cup of fortified soya milk); cheddar (1.12 mcg in 4 ounces): cottage cheese (2.4mcg in one cup): yeast extract (usually enough for an adult’s R.D.A. but amount may vary, check the label); and most health food shops will also sell other products that have vitamin B12 in them too.
Folic Acid is particularly abundant in green leafy vegetables (the name comes from ‘foliage’), but is not commonly found in meat or meat products addition, it is easily destroyed by cooking unless it is protected by a naturally acidic environment, such as ascorbic acid (vitamin C).
Cooking and re-heating food may destroy virtually all the folic acid it contains, so this is an excellent reason to ensure that your diet always contains a good quantity of fresh green leafy vegetables, and to shun over-processed, stale, junk food.
Forms of mental illness
A suggested intake is 400 micrograms for adults, 800 micrograms in pregnancy and 600 during lactation. Deficiency of this vitamin will result in poor growth, anaemia, susceptibility to infection, and recent research has associated lack of folic acid with certain forms of mental illness. It has been used to treat patients suffering from atherosclerosis, stomach ulcers, menstrual problems, and even grey hair!
Here are some good sources: brewer’s yeast (192mcg in one tablespoonful): yeast extract (240mcg in one tablespoonful); raw beetroot (126mcg in 1 cup, try it grated in a salad, delicious!); cooked spinach (164mcg in 1 cup); wheat germ (420mcg in 1 cup, toasted): orange juice (136mcg in one cup): almonds (136mcg in one cup): roasted peanuts (153mcg in one cup): black eye beans (168mcg in one cup, cooked) and broccoli (219mcg in 3 pieces, cooked).
Vitamins for body health! Sources from foods
Nicotinic Acid is part of the B group that occurs in several forms including niacin, nicotinamide, and niacinamide. Once again, it is easy to obtain, being available both in a direct dietary form and also being synthesized internally by the body from the amino acid tryptophan (found in nuts, dairy products and pulses).
Some good sources are: nori (10mg in 100 grams), brewers yeast powder (9.4mg in 25 grams), barley (dry, 3.7mg in 100 grams), and dried apricots (3.3mg in 100 grams). The suggested intake of nicotinic acid (or nicotinic acid equivalent).
Since the amino acid tryptophan is converted into nicotinic acid by the body at the rate of 60mg tryptophan to Img nicotinic acid, and since it is not easy to determine how much tryptophan is present in foods, no Nutrition-Checker information is given for this vitamin.
However, it is quite easy to obtain a good supply of nicotinic acid in the diet. Pantothenic Acid is another B group vitamin that works closely with the others to metabolize fat and carbohydrate into energy that the body can use. It is very widely found in natural foods (although processing and freezing will destory it) and the Ministry of Agriculture Fisheries and Food comment in their Manual of Nutrition:
Dietary deficiencies of this vitamin are unlikely in man because it is so widespread in food: A good supply of the other B group vitamins will ensure that you get enough Pantothenic Acid.
Vitamins for body health! Vitamin C
Vitamin C has suffered from a lot of hype for its alleged ‘miracle properties, but notwithstanding all that, it’s still quite an incredible vitamin. Humans are almost alone (apart from the great apes and some guinea pigs) in our dietary need for it – most other animals can synthesize it in their own bodies but, since we can’t, we need
to take in a regular supply of it in our diet.
This isn’t always easy. A diet that contains a large proportion of meat, oils, tea, coffee,alcohol, pastry and other refined carbohydrate foods (and any processed foods) may well be vitamin C deficient. In other words, a typical meat oriented, fast food diet.
Fisheries and Food
As the Ministry of Agriculture Fisheries and Food say: this vitamin remains one of the few nutrients in which the British diet can be deficient. What happens when you suffer from a lack of vitamin C? Well eventually, you contract scurvy and die (scurvy was the curse of the early long-distance sailors who couldn’t obtain fresh fruit and vegetables).
But long before that, you will begin to suffer from sub-scurvy symptoms. The onset of these symptoms is quite quick once your diet becomes vitamin C deficient. They include: bleeding from the gums and from small blood vessels (causing tiny red dots of blood to be visible under the skin), poor stamina and general debility, shortness of breath, easy bruising, nosebleeds anaemia.
Vitamins for body health! Vitamin C deficient
Slow healing of wounds and a marked decrease in your resistance to infections. Since blood clots may form at the point where your capillary wall has ruptured, it is quite likely that vitamin C deficiency may predispose people to heart attacks and strokes.
The function of vitamin C in the human body is basically to promote the formation of connective tissue, and so it plays an important role in the body’s continuing regeneration of itself as well as in healing wounds. It helps to fight bacterial infection and may reduce the effect of certain allergies on the human body. It’s needed by the bones and teeth to keep them healthy and strong, and also helps metabolize certain proteins.
Other vitamins against destruction
It has also been found to protect other vitamins against destruction in the body before they can be fully utilized. These are just some of the functions that vitamin C fulfills – as you can see, it’s a pretty useful substance. The suggested intake of vitamin C ranges from 15mg a day for children under one year to 60mg a day for pregnant or lactating women.
The average R.D.A. is about 30mg a day. Don’t rely on cooked food to give you this. In fact, you can’t even rely on raw food, if it’s several days old, because vitamin C decays rapidly, and is sensitive to light and heat. Cooking vegetables in copper pans will also destroy vitamin C. For these reasons, and cause the amount of vitamin C in foods can very widely, we can’t really give Nutrition-Checker data for this vitamin but we can tell you where you’re likely to find it in the sort of amounts that you need.
Vitamins for body health! Vitamin C sources
As vitamin C is generally well-preserved in acid environments, citrus fruits are usually a good source. One cup of fresh orange juice may give you as much as 120mg, which is enough to satisfy anyone’s R.D.A. Other good sources are red and green peppers, bean sprouts (sprout them yourself to ensure perfect freshness. it’s easy and they’re much more tasty than supermarket ones). potatoes, spinach (one cup cooked will give you about 50mg), cabbage, broccoli and brussels sprouts.
Some people have indulged in massive doses of vitamin C and report that it can treat, among other things, the common cold. hepatitis, herpes simplex, and drug addiction. Some symptoms are associated with continual over-dose, such as skin rashes loose bowels, and a burning sensation during urination, but these are associated with very considerable intakes, up to 15,000mg per day.
Smoker be careful!
There seems to be little point in taking such massive doses of vitamin C. since what the body cannot use is immediately discharged into the urine. It would be more sensible to take smaller, more frequent doses that the body can more easily process-preferably, by eating a good fresh diet. Smoking will deplete the body of vitamin C by anything up to one-third of the total amount present. Other kinds of stress will also result in depletion, and this should be taken account of in the diet.
Also, our need for vitamin C may increase with age, since the body has a greater need to regenerate its collagen. A dirty environment – such as the urban pollution that most of us now have to contend with — may also increase our need for this vitamin.
This has been called the ‘Sunshine Vitamin, because (even in our grey climate) that is precisely where most of us get it from. The sun’s rays act on a fat contained in our skin, and convert it into vitamin D. This is a pretty efficient process and perhaps surprisingly, most people get enough vitamin D this way. Vitamin D is dissolved in fat, rather than water, and so the body finds it less easy to flush any excess out of the system. Consequently.
In order to prevent a toxic dose, vitamin D dietary supplementation should only take place under medical supervision when it is known that a deficiency exists, or for pregnant or lactating women. Some food sources of vitamin D include: skim milk (if specially fortified), whole milk, egg yolk, butter, seafood and cream.
Margarine is also fortified with it. It helps to prevent rickets, and generally helps in teeth and bone growth and development.
Vitamins for body health! Vitamin E
This vitamin, once again, is not found to much extent in meat or meat products. The main sources are cereals, eggs, and vegetable oils – indeed, such vitamin E as exists in meat is derived, by the animal, from a plant source.
There are several different types of vitamin E, all called tocopherols. They are fat soluble, and act essentially as preservatives or anti-oxidants. Food processing will remove much of the vitamin E it contains, so cold-pressed vegetable oils are to be preferred on this account (yes they may be more expensive, but they’re worth it, and the higher price may discourage you from using too much). A meat orientated diet that is high in saturated fat and low in vitamin
E may lead to the formation of various harmful products of fat decomposition in the body. On the other hand, there should be no need in a well-balanced meat-free diet to worry about vitamin E deficiency. Some naturally good sources are: wheat germ, sunflower oil, soya oil, and most nuts and seeds.
For Further Reading: Calcium and iron for healthy body!