Fact Files : Basic Facts About Food

Nutrition is a process that serves two purposes: to provide energy and to maintain body structure and function. Food supplies energy and the nutritional components needed for body function. Food is made up of six major classes of nutrients as shown.

Three major nutrients (macronutrients) which are essential for good health include proteins, fats and carbohydrates.
The energy from protein, fats and carbohydrates is used by the body for different purposes:

• Carbohydrates have one major function in the body – to provide energy and fuel. Although fats and protein can also be used to generate energy, carbohydrates are preferred. In fact- the brain, nervous system and red blood cells must have a constant supply of carbohydrates to keep working.
  
  

• Proteins are needed for growth and repair of body tissues. It provides the building blocks needed to replace worn or damaged cells. The cells of our skin, nails, hair, veins, arteries, bones, blood cells, immune factors like antibodies etc require a constant supply of proteins to regenerate.
  
  

• Fats are the major storage form of energy in the body. Fat provides insulation and cushioning for internal organs and ‘spares’ protein for its primary role of building new cells. It also is a carrier for fat soluble vitamins.
  
  

• Water is an essential nutrient we can only survive a few days without. It is essential for a range of vital functions to take place such as carrying these nutrients and waste products throughout the body and maintaining blood volume just to name a few.

Food also provides micronutrients which are important for good health and include vitamins and minerals.
Vitamins and minerals are needed for the various chemical reactions involved in the release of energy from carbohydrate, protein and fat. Enzymes are needed for these chemical reactions to take place. Enzymes are protein molecules which contain minerals and vitamins as part of their structure. The minerals and vitamins do not provide energy themselves but work as catalysts so the reactions which release energy in the body can proceed. You could think of them as internal spark plugs for your body’s internal body engine.

Non-nutrient components in foods

Apart from food containing six major nutrients, some foods also contain naturally occurring components known as antioxidants and plant sterols which are one of the reasons plant based foods like fruits and vegetables are so good for you.

Antioxidants include vitamin C, vitamin E, beta carotene, and flavonoids and are found in vegetables, fruit, wholegrain cereals and cereal products, tea and vegetable oils and spreads. It is suggested that antioxidants may delay or prevent the onset of diseases induced by 'free radicals' by stopping these harmful molecules from attacking and damaging healthy cells in your body. By enjoying foods rich in antioxidants you can help reduce your risk of heart disease, cancer, asthma, and stroke. They may play a special role in protecting the brain.

Plant sterols are natural substances mainly found in plant based foods like vegetable oils, nuts, seeds, legumes (dried peas, dried beans and lentils), breads & cereals, fruit and vegetables, but have also been added in stronger amounts by manufactures to margarine spreads (i.e. MeadowLea Logicol® and Flora Pro-activ®). They have been shown to block the absorption of cholesterol thereby reducing blood cholesterol levels and decreasing heart disease and stroke risk.

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