Vitamins are essential for good health, but too many could do   more harm than good.

Vitamins are organic compounds used in tiny amounts by our body to work properly and fight illness. Many of them form the essential parts of enzyme systems that are involved in energy production and exercise performance;  others are involved in the functioning of  the immune system and nervous system.

Vitamins are loosely divided into two groups. The first is water-soluble, such as vitamin C and all the B vitamins. These are quickly lost by the body, so they need to be replaced on  a regular basis. The second kind are fat-soluble such as A, D, E and K. These vitamins could be stored in the body for months and even years.

How much should I take?

To be sure that you stay within the limits of any particular supplement, a figure shown as RDA ( recommended daily allowance) has to appear on the labels of all supplements. This represents the amount of vitamin or mineral needed  by an average  adult man in order to maintain good health. If you do go over the board with water-soluble vitamins such as vitamin C, they should simply be washed away in your urine. Taking too many fat-soluble vitamins such as vitamin A, which can be stored in your liver, could lead to toxicity problems.

Antioxidants

Some vitamins are also antioxidants. These are molecule that are capable of preventing or slowing the oxidisation of other molecules . They could neutralise  free-radical damage which is thought to be the root of many human diseases including several cancers. They are also responsible for much of the aging process and for post-exercise soreness.

Antioxidants neutralise free-radicals (chemical compounds containing one or more unpaired electron) by donating one of their own electrons. They also repair any damage the free-radicals have caused and replenish our bodies as the best they can.

Where can I find them?

To make sure you are getting enough antioxidants, include at least five portions, ideally more,  of fruit and  veg in your daily diet. Try to include as many food colours as possible – Green leafy veg, red tomatoes, purple aubergine, orange, carrots, bananas, and so on – you will stand an even better chance of getting all the  antioxidants you need:

• Betacarrotene found in carrots, sweet potatoes and apricots
• Vitamin C found citrus fruit, peppers, strawberries and kiwi fruit
• Selenium  found in fish, brazil nuts and wholegrains
• Lutein found in Spinach, Kale, and most green leafy veg
• Flavanols  found in  dark chocolate
• resveratrol found in red wine
• Lycopene found in tomatoes, peppers and watermelon

Remember  to also include nuts and seeds

Vitamin A

Vitamin A is an essential nutrient needed in small amounts for the normal functioning of visual system; growth and development; and maintenance of cells, immune system and reproduction.
A small portion of plant rich in carotenoids such as 50 grams of cooked corrot can provide the recommended daily intake of vitamin A. Mangos, papaya, melon, green leafy vegetables and ref palm oil are a good source of vitamin A. Vitamin A is also present in fish and chicken liver.

Vitamin C

Citrus fruit and other food rich in ascorbic acid are rich in vitamin C. One single orange can provide the daily recommended vitamin C intake. Guava, amla, kiwi, cranberries, strawberries, papaya, mango, melon,
cantaloupe, spinach, Swiss chard, tomato, asparagus, and Brussels sprouts are a good source of vitamin C. Minimal cooking ( steaming or stir-frying ) is recommended to maximise the bio-available nutrient.

Vitamin D

Vitamin D is essencial for maintenance of normal blood levels of calcium and phosphate, which are needed for bone mineralisation, muscle contraction, nerve conduction and general cellular function. Vitamin D is usually aquired by exposure to sun light: 30 minutes of skin exposure of the arms and face can provide all the daily vitamin D needed to the body. Ageing process, latitude, season, skin pigmentation, clothing and sunscreen use may reduce the ability of the skin to provide the total needs of the individual.

Vitamin E

Reactive free radicals are involved in many diseases, including heart diseases and cancers. Our cells contain many potentially oxidizable substances such as polyunsaturated fatty acids, protein and DNA. The body needs a complex antioxidant defence system to protect the cells from the effects of free radicals and pollutants. The consumption of food rich in antioxidants may play an important role in modifiying the development of heart diseases and cancers.
Vitamin E is a major lipid-soluble antioxidant that is exclusively obtained from our diet. Vitamin E can be found in wheat germ oil , sunflower, nuts, green leafy vegetables and sweet potato.

Vitamin K

Vitamin K is known to be needed to coagulate blood and maintain proper bone density. It also plays an important role in the development of the fetus . The main intake of vitamin comes from either our diet or synthesis from intestinal bacteria. Green leafy vegs such as lettuce, kale and broccoli are high in vitamin K. A diet that includes nuts, fruits, spices and mints could block vitamin K – the reason why aspirin can ‘thin’ the blood. High amount of vitamin A and E can also block vitamin K.

The recommended dietary allowance (RDA) for vitamin K is

• 80 mg per day for an adult male
• 65 mg for an adult female
• 5 mg/day for a newborn infant

There is no known toxicity associated with high doses vitamin K.