AS DOCS HAIL D AS A COLD-BUSTER...

VITAMIN A Found in: Beef, liver, carrots, spinach, butter and eggs.

Most people get enough of this nutrient from a healthy diet. It is linked to healthy skin and vision, and boosts the immune system. As a supplement it is really best taken as part of a multi-vitamin, not individually, as being a fat-soluble vitamin, it can be stored in the body and so can easily reach toxic levels. Vitamin A must also be avoided in pregnancy – even in a multi-vitamin – as high levels can harm the baby.

VERDICT: NOT WORTH IT BETACAROTENE

Found in: Peppers, carrots, sweet potato, melon and apricot.

In plentiful supply in many fruit and veg, taking more than the recommended dosage of betacarotene – the orange pigment which the body converts into Vitamin A – has been found to increase the risk of developing lung cancer and heart disease by up to 20%. Betacarotene should therefore be avoided by smokers, as it may increase their risk of lung cancer.

VERDICT: NOT WORTH IT VITAMIN B12

Found in: Animal products, so meat, fish, dairy and eggs.

B12 is important for making red blood cells, keeping the nervous system healthy and for releasing energy from the food we eat. Vegans and vegetarians are susceptible to deficiency and will need to take a supplement to boost their levels. Try Holland & Barrett Vitamin B12 tablets, £7.99. VERDICT: WORTH IT

VITAMIN C

Found in: Citrus fruits, berries, tomatoes, peppers and peas.

Despite popular wisdom, recent studies suggest taking immuneboosting Vitamin C in pill form makes little difference to preventing colds, although one study did find it may shorten the life of a cold by one day. Also, our body can’t store it, so any excess is just excreted in our pee. VERDICT: NOT WORTH IT

CALCIUM

Found in: Dairy products, canned fish in which you eat the bones, dried apricots, watercress and almonds.

Calcium is vital for healthy bones and teeth, but a supplement is only advised if you are vegan, eat very little dairy or have osteoporosis.

VERDICT: WORTH IT VITAMIN D

Found in: Oily fish and eggs have tiny amounts, but our main source is the action of sunlight on skin.

A recent draft report by the Scientific Advisory Committee on Nutrition concluded that all adults require 400 IU (10 micrograms) of Vitamin D a day – an amount almost impossible to get from diet and sunshine alone in the UK. Try: Healthspan Vitamin D3 10mcg, £7.95 for 240. Go to healthspan.co.uk.

VERDICT: WORTH IT VITAMIN E

Found in: Almonds, avocado, olive oil and dark-green veg. This antioxidant is important for skin, eyes and the immune system and is safe to take as part of a balanced multivitamin. However, there is no evidence that a supplement can boost heart health or fight premature ageing as once hoped.

VERDICT: NOT WORTH IT FOLIC ACID

Found in: Liver, whole-grain breads and cereals, green leafy veg.

Folic acid supports healthy red blood cells and reduces the risk of conditions such as spina bifida in unborn children, so anyone trying to conceive or already pregnant should be taking 10mcg daily. For a supplement, try Boots Folic Acid 400ug, £1.99 for 60.

VERDICT: WORTH IT IRON

Found in: Red meat, game, darkgreen leafy veg and in some of the dried fruits.

Iron is vital for healthy red blood cells and doctors will prescribe a supplement to people found to have low iron – anaemia – in a blood test, for instance, women with heavy periods or vegetarians. However, taking an iron supplement can cause constipation and, in the long term, poisoning resulting in brain damage or death, so only people with a proven deficiency should take a supplement.

VERDICT: NOT WORTH IT (UNLESS PRESCRIBED) OMEGA-3 FATS

Found in: Oily fish such as salmon, sardines and mackerel, some nuts.

Anyone who doesn’t eat oily fish every week should take this. Low levels of Omega-3 fats have been linked to poorer heart health and brain function and is a common deficiency because we just don’t eat enough food that contains it. Try Boots Omega 3 Fish Oil, 1000mg, £5.99 for 60 capsules.

VERDICT: WORTH IT MULTI-VITAMINS

Found in: A healthy, well-balanced and varied diet.

Children aged five and under should take a supplement containing Vitamin, A, C and D, according to Government recommendations, especially if they are fussy eaters. They could also be helpful if you are a smoker, heavy drinker, are on a very low-calorie diet or if you are not eating a varied diet with five portions of fruit and veg a day. Try Boots Multibionta Vitality, £5.99 for 30.

VERDICT: WORTH IT (FOR SOME) ZINC

Found in: Meat, shellfish and dairy foods. Although this mineral is vital for a healthy, strong immune system, few studies have found any benefit for healthy people taken as a tablet. It may be a useful part of a multivitamin for people on restricted diets or for heavy drinkers.

VERDICT: NOT WORTH IT