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Food types - the seven components of a balanced diet

An explanation of the foodstuffs needed to have a healthy diet

The seven components of a balanced diet

FunctionExamples
CarbohydratesProvide quick and efficient energy for movement.Fruit, honey, biscuits, bread, rice, pasta, cereals.
ProteinsRepair, growth and efficient working of all the body tissues.Meat, fish, dairy, lentils, nuts, seeds.
FatsProvide energy very slowly, protect vital organs and help prevent heat loss.Meat, cheese, cream, fish, nuts.
MineralsEssential for many processes such as bone growth/strength, nervous system, red blood cells, immune system. Need small amounts only.Calcium 鈥 milk, canned fish, broccoli; iron 鈥 watercress, red meat, nuts; potassium 鈥 bananas, pulses, white meat.
VitaminsVital for the production of energy, the prevention of disease and the working of the metabolism. Need small amounts onlyA 鈥 liver, dairy, green veg, yellow fruit; B 鈥 vegetables, wholegrain cereals, peanuts; C 鈥 citrus fruit, vegetables; D 鈥 oily fish, eggs.
FibreEffective bowel function and healthy digestionFruit, vegetables, nuts, cereals
WaterMain component of blood and cells, helps carry nutrients and remove waste products, helps regulate body temperature.Fluids and foods.
Carbohydrates
FunctionProvide quick and efficient energy for movement.
ExamplesFruit, honey, biscuits, bread, rice, pasta, cereals.
Proteins
FunctionRepair, growth and efficient working of all the body tissues.
ExamplesMeat, fish, dairy, lentils, nuts, seeds.
Fats
FunctionProvide energy very slowly, protect vital organs and help prevent heat loss.
ExamplesMeat, cheese, cream, fish, nuts.
Minerals
FunctionEssential for many processes such as bone growth/strength, nervous system, red blood cells, immune system. Need small amounts only.
ExamplesCalcium 鈥 milk, canned fish, broccoli; iron 鈥 watercress, red meat, nuts; potassium 鈥 bananas, pulses, white meat.
Vitamins
FunctionVital for the production of energy, the prevention of disease and the working of the metabolism. Need small amounts only
ExamplesA 鈥 liver, dairy, green veg, yellow fruit; B 鈥 vegetables, wholegrain cereals, peanuts; C 鈥 citrus fruit, vegetables; D 鈥 oily fish, eggs.
Fibre
FunctionEffective bowel function and healthy digestion
ExamplesFruit, vegetables, nuts, cereals
Water
FunctionMain component of blood and cells, helps carry nutrients and remove waste products, helps regulate body temperature.
ExamplesFluids and foods.

Additional information on the components of a balanced diet

Carbohydrate

There are two types of carbohydrates:

  • simple carbohydrates or sugars such as biscuits and jam
  • complex carbohydrates or starches such as bread and rice

Complex carbohydrates give a steadier source of energy. The liver and muscles store large amounts of carbohydrate in the form of glycogen; the blood stores small amounts of carbohydrate in the form of glucose. Carbohydrates are a very important part of an athlete's diet because of the way they release energy.

Protein

Protein is broken down into amino acids which are the building blocks of body tissue and are necessary for the production of haemoglobin in the blood. Protein is also an energy source, but it is much more difficult to use than carbohydrate or fat.

Fat

There are four types of fat:

  • monounsaturated fats such as olives and peanuts
  • polyunsaturated fats such as oily fish and sesame seeds
  • saturated fats such as sausages and butter
  • trans fats such as cake and takeaway food

Mono and polyunsaturated fats provide essential fatty acids and help maintain a healthy cholesterol level. Saturated and trans fats increase the cholesterol levels in blood which increases the risk of coronary heart disease.

Fat is a major energy source for low-intensity endurance exercise, but it takes the body longer (than carbohydrate) to process it as a great deal of oxygen is required.

Minerals

There are two types of minerals:

  • macro-minerals, which are needed in larger amounts (for example calcium and potassium)
  • trace elements, which are needed in very small amounts (for example iron and zinc)

Minerals can be lost through sweating, so a sports performer鈥檚 diet should ensure minerals are replaced to maintain good health.

Iron is an important mineral because it is an essential component of haemoglobin (which carries oxygen in the blood).

Calcium is essential for healthy bones and teeth. A deficiency in calcium means a greater chance of osteoporosis and bone fractures.

Potassium is a mineral which aids muscle contraction, maintains normal blood pressure and promotes healthy skin.

Vitamins

The body cannot produce vitamins (apart from vitamin D) so a healthy diet should include them.

Vitamin A is needed for good vision and healthy skin.

Vitamin B is needed for energy production and stress reduction.

Vitamin C is needed for fighting viruses and healing wounds. It also keeps skin and gums healthy.

Vitamin D is needed to build bones and teeth.

Fibre

Fibre has no calories but adds bulk to our food which aids digestion and absorption. It also helps to prevent bowel cancer.

Water

The body needs to be hydrated to stay healthy. Fluid is lost in sweat, urine, faeces and exhaled air. Failing to replace lost fluids can result in . This is a more serious condition than lack of food. Women should drink around 1.6 litres (approximately eight glasses) of fluid and men should drink around two litres (approximately ten glasses) of fluid per day. This varies according to the temperature and how rigorous the exercise.

Water in the blood helps to control body temperature by absorbing heat produced during exercise. This heat is then carried to the skin where it is lost to the air through convection. Water as sweat helps cool the body when it evaporates on the surface of the skin.