Vitamins: Fact and fiction
Vitamins and minerals are important for the body's health. Most people get enough of them for their needs from a balanced healthy diet and safe exposure to the summer sun. However, in some cases supplements may be recommended.
Vitamins and minerals are substances your body needs for normal growth and functioning. Some facilitate crucial chemical reactions, while others act as building blocks for the body.
There are strict rules on what claims can be made for supplements sold in shops and reputable websites. However, wilder claims with no scientific evidence to back them up continue to be made online.
Nutritional deficiencies can cause health problems like rickets and scurvy. However, taking more than recommended levels of some vitamins cause health problems, or interfere with medication. That's why it is important to seek medical advice before taking any new supplement.
Maintaining a healthy diet
It's easy to get enough micronutrients from your food if you maintain a healthy diet. But many people fail that test. They will eat two or three servings of fruits and vegetables per day rather than the recommended five. That's why multivitamins are sometimes seen as a sort of nutritional safety net.
But it's just a safety net. Vegetables, fruit and whole grains contain fibre and a host of other important nutrients that cannot be adequately delivered through pills.
No supplement can ever be a substitute for a healthy diet and exercise.
Choosing a supplement
It's easy to become overwhelmed when looking at the dietary supplement shelves of a health food shop or even your local supermarket.
Multivitamin manufacturers typically produce different varieties for men, women, children and older people. For example, pre-menopausal women need more iron than children or the elderly.
Folic acid supplements are recommended whilst a woman tries to become pregnant and during the first 12 weeks of pregnancy.
Calcium is important helping for bones, teeth, blood clotting and muscles, including the heart.
Adults need 700mg of calcium a day, most of which should be able to come from a healthy diet that includes dairy products.
Taking 1,500mg or less a day calcium supplements is unlikely to cause any harm, but more than that can cause stomach pain and diarrhoea.
Vitamin D works with calcium in the body to keep bones and teeth healthy.
Too little vitamin D can contribute to rickets in children, and bone pain and osteomalacia in adults.
Vitamin D is found in some food, including oily fish and fortified spreads. However, most of our vitamin D comes from safe sun exposure during the summer. It is hard to get the daily amount of vitamin D needed from food, so since the summer of 2016, health officials say most adults and children aged 4 and over should consider taking supplements containing 10 micrograms of vitamin D every day during autumn and winter.
You can't get too much vitamin D from the sun.