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Vitamins, minerals and exercisePublished by Bupa's health information team, healthinfo@bupa.com, April 2008 This article is for people who exercise and want to know about vitamins and minerals. It discusses whether athletes have different needs, and whether vitamins and minerals can improve your sporting performance. What are vitamins?Vitamins are nutrients that everyone needs in small amounts for the body to work properly. Different vitamins have different functions. For example, some enzymes need particular vitamins to work, and other vitamins stop oxygen from damaging your cells. Your body can't make most vitamins apart from vitamin D, so you have to get them from the food you eat. There are two types of vitamins:
Water-soluble vitamins (such as vitamins B6, B12, C and folic acid) are found in fresh fruit and green vegetables. It's best to eat green vegetables raw, steamed or grilled rather than boiled because the vitamins can easily be destroyed by cooking. What are minerals and trace elements?Minerals and trace elements are inorganic elements that are needed in small amounts for your body to function. They are as essential as vitamins and your body needs to get them from the food you eat. For example, you need:
Minerals and trace elements are mainly found in meat, cereals, fish, milk and dairy foods, vegetables, dried fruit and nuts. How much do I need?Nutritional needs vary from person to person, depending on gender, age and activity levels. The Department of Health gives guidance on the correct levels of nutrients in the diet although these are not exact recommendations. They are called dietary reference values (DRVs) and are usually listed on food and supplement packets. DRVs show the amount of energy or an individual nutrient that a group of people of a certain age range (and sometimes sex) need for good health. Why are vitamins, minerals important if I exercise?When you exercise your nutritional needs change because your body needs more energy to pump the blood around your body, increase muscle activity and burn fat. Vitamins and minerals are needed to build and repair your muscle tissue and strengthen your joints and bones. Calcium and vitamin DCalcium and vitamin D are important for building and repairing bones and maintaining teeth. Vitamin D helps your body absorb calcium. Your body makes most of the vitamin D you need when you expose your skin to the sun. But sports nutrition experts suggest taking a five micrograms (ug) daily vitamin D supplement if you train indoors (for example ice skating) or if you don't expose your skin to sunlight. If you do not get enough calcium and vitamin D your bones will become weak and more likely to break, as a result of a minor bump or fall, or even without an injury. Good sources of calcium include dairy products, bony fish and dark green leafy vegetables. IronIron is a vital part of the blood, allowing it to carry oxygen around your body. It's common for iron to be low in people who exercise intensively, especially women and distance runners. A shortage in iron leads to anaemia, which can impair performance and affect your health. Good sources include red meat, dried fruit and dark green leafy vegetables. ZincZinc plays an important role in growth, building and repair of muscle tissue, and energy production. Good sources include meat, shellfish and wheatgerm. B vitaminsB vitamins may be particularly relevant for athletes because they are important for energy production during exercise, the production of red cells, protein synthesis, and in tissue repair and maintenance. You may need up to twice the recommended amounts of these: thiamine riboflavin, niacin, pantothenic acid, folic acid, B-6 and B-12. Different B vitamins are found in a wide variety of foods, including meat, cereals, milk and eggs. Antioxidant vitaminsThe antioxidant vitamins A, C, E, selenium and beta-carotene are important for protecting your cells from damage by oxygen. In theory, intensive exercise could cause more cell damage. However, your body may adapt to this. Sports nutrition experts are not sure whether you need to take in more of these vitamins if you exercise a lot, but you may need to if you restrict your calorie intake or follow a low-fat diet. Vitamin C is found in fruit and vegetables, such as peppers, oranges and kiwi fruit; vitamin A is found in eggs, cheese and milk; and vitamin E is found in olive and soya oil. For more information about vitamins please see the table, Vitamins and minerals - where are they found and what role do they play in our body? How can I get enough vitamins and minerals?You should be able to get all the vitamins and minerals you need by eating a healthy balanced diet. You should aim to eat at least five servings of fruit and vegetables each day. Your meals should contain starchy foods (such as bread, potatoes and pasta) and moderate amounts of protein-rich foods (such as dairy products, meat, fish and pulses). You may want to gain or lose weight to improve your performance. You can gain weight healthily by increasing your calorie intake and increasing strength training to build muscle. But weight loss can sometimes cause problems because restricting calories can leave you short of nutrients, including vitamins and minerals. Some vitamins, particularly fat-soluble vitamins, can be harmful in excessive quantities. For example too much vitamin A can cause headaches, skin changes and damage your liver. You shouldn't follow a special diet or take vitamin supplements without the advice of a trained sports nutritionist or registered dietician. He or she can advise you on the right foods and quantities to eat to make sure you get all the nutrients your body needs. Will vitamin and mineral supplements improve athletic performance?Evidence suggests that unless you are deficient in a nutrient, taking a supplement of that nutrient won't improve your performance in sport. Vitamin supplements will not make you feel less tired when you exercise. Key points
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