Does your body need vitamin supplements?

The array of vitamins our bodies need to function at top capacity is dizzying - and that's before we get started on minerals like iron. Broadly speaking, they're divided into fat-soluble and water-soluble vitamins.

Your bodies can store supplies of fat-soluble vitamins in your fatty tissues and liver, calling them up and using them when it needs. That means you don't need a daily supply in your diet. Fat-soluble vitamins - A, D, E and K - are largely found in liver and fatty foods such as oily fish, egg yolks, fortified spreads and dairy products.

Vitamin A

Your body can also make vitamin A from beta carotene, found in vegetables such as carrots, peppers, spinach and yellow fruits. Getting enough vitamin A is important for a strong immune system, as well as good eyesight (especially in dim light).

However, if you have too much, your bones may become more brittle and prone to breaking if you fall. Too much vitamin A when you're pregnant can result in birth defects. You don't need supplements if you have a reasonable diet, and you should avoid eating any fish liver oil, liver or liver pate if you're pregnant, or too much if you have osteoporosis.

Vitamin K

Vitamin K is needed for blood clotting, helping you to stop bleeding when you cut yourself. Along with vegetable oils, a huge array of foods including broccoli, spinach, Brussels sprouts and curly kale contain vitamin K. You shouldn't need to take a supplement.

In fact, if you take the blood-thinning medicine warfarin (commonly prescribed if you have an abnormal heart rhythm called atrial fibrillation) you should be careful about eating and of these foods. That's because they can interfere with the effect of warfarin.

Vitamin D

Vitamin D is the exception where supplements are concerned - and that's largely because it's almost impossible to get enough from your diet. It helps keep muscles and bones strong, and may protect against heart disease and even cancer. About 90% of the vitamin D in our bodies is made in our skins when we're exposed to sunlight. So in the UK, you should take a 10 microgram supplement from October to April. If you're over 65, pregnant, breastfeeding, one- to five-years-old, housebound or don't get out much, you should take the same supplement all year round. Your pharmacist can advise you.

Vitamins B and C

All the B vitamins and vitamin C are water-soluble. On the plus side, if you have too much of them, your body just passes them out of your system in your urine, so it's very difficult to get too much of them. On the down side, you need to include them in your diet every day, as your body can't store them. Lots of vegetables are high in vitamin C, but prolonged cooking (especially boiling) means you lose some of the vitamin content of foods.

There are several different B vitamins with a range of functions, mostly related to keeping your blood cells, skin and nervous system in good shape and releasing energy from the food we eat. Most people should be able to get enough from a balanced diet. But if you drink a lot of alcohol, your doctor may prescribe regular supplements of vitamin B and Thiamine. That's because when your body processes alcohol, it uses up a lot of vitamin B.

Fizzy vitamin tablets contain a lot of salt. If you do take supplements, consider changing to a non-effervescent version. All pregnant women should take a folic acid supplement until 3 months into pregnancy - ideally starting before you get pregnant.

If you have osteoporosis, your doctor may recommend calcium and vitamin D supplements - particularly if you don't eat a lot of dairy foods. If you have heavy periods, you may need regular iron supplements. Otherwise, rather than making for the supplements aisle, stock up on fruit, veg and wholegrains instead to get a healthy dose of vitamins!

With thanks to 'My Weekly' magazine where this article was originally published.