Most people who take Vitamin and mineral supplements self-prescribe to what they think they should take, not even what is fashionable. As well as being a waste of money, this is likely to do more harm than good. Why? Because taking an extra dose of one Vitamin can lower levels of another. Falling short of a particular mineral can prevent the absorption of another, seemingly unrelated one. A dose of an isolated Vitamin or mineral that is too high can produce the same symptoms as a deficiency of another nutrient.

This is what nutritionists call synergy and it explains why taking extra calcium to build stronger bones may backfire on you. Too much calcium in the body can cause a deficiency in iron, zinc, magnesium and phosphorous by preventing their proper absorption. All these minerals are vital for good bone health and their ongoing deficiency can lead to osteoporosis – the condition you were trying to prevent by taking calcium supplements.

Vitamin D, which is also known as the sunshine Vitamin, since the body needs exposure to sunlight to make it, enhances the absorption of calcium, but too much can cause a potassium deficiency. Vitamin A is an antioxidant that is said to help to prevent premature aging. It does help to maintain the surfaces of the body,including the skin, but too much increases the body’s need for another antioxidant, Vitamin E, which protect against heart disease.

Vitamin C remains the most popular of the self-prescribed supplements: an estimated ten million Britons take it every day. Research papers now prove that it has powerful antioxidant properties that protect against cancer and heart disease and show how it boosts the immune system to protect against infections and can even speed up wound healing. Yet not many people know that it works much better in the presence of Vitamin A or that, to use it properly, the body needs calcium. Ask any alternative cancer specialists what nutrients their patients should be eating and they will specify bioflavanoids. Though not a true Vitamin, these are a group of biologically active substances found in plants that are sometimes called Vitamin P.

As well as cancer-fighting properties, they also have an antibacterial effect in the body, where they promote healthy circulation, stimulate bile production for the breakdown of fats and lower blood cholesterol levels. Foods that are rich in flavanoids include apples, beetroot, blackberries, cabbage, carrots, cauliflower, cherries, dandelions, lentils, lettuce, oranges, parsley, plums, peas, potatoes, rhubarb, rose hips,spinach, tomatoes, walnuts and watercress. But what you may not know is that they all work even better when taken with Vitamin C, and vice versa.

Synergistic partners are rarely monogamous. To correct a deficiency in Vitamin A, you also need six additional nutrients: choline, zinc, Vitamin C, D and E, plus the essential fatty acids found in oily fish or evening primrose oil supplements. To restore normal levels of Vitamin C, you need the bioflavanoids, Vitamin A, plus calcium and magnesium. Those last two minerals are so closely linked that if you plan to take a supplement, you need to follow a ratio of 2: 1 in favor of the calcium. So if you are taking 800 mg of calcium, you need to take 400 mg of magnesium, too.

To correct a shortage of calcium in the hope of building stronger bones, you also need magnesium, boron, manganese, phosphorous, Vitamins A, C, D and F, plus essential fatty acids. To complicate the picture further, synergy may not affect the whole body but only specific cells, so the impact of what you are doing may be hidden. Smoking, for example, wipes out Vitamin C in the body, but this deficiency may be confined to the cells of the lungs. As you can see, when taking supplements you have to make sure that the Vitamin and mineral balance in your body is maintained.