Food for Life
All food contains nutrients which our bodies need to work properly and stay healthy. There are different kinds of nutrients, each with their own functions. For a healthy diet, we need a balance of all of them.
- Carbohydrates are needed for energy.
- Protein helps your body grow and repair itself.
- Fats provide energy plus insulation for the body.
- Vitamins are needed in very small amounts and are used for growth and development. For example, vitamin C keeps the skin healthy and vitamin B helps you to use your energy from carbohydrates.
- Minerals are also not needed in large amounts but without them we would become ill. For example, calcium is needed for strong bones and teeth, and iron for making our blood.
We also need fibre which helps food move smoothly through the body to get rid of any waste. Water is also essential for our bodies to work properly.
What's a balanced diet?
No single food contains all the nutrients the body needs, so you need to eat a mix of different foods. For a balanced diet, you should eat foods from the different groups but in the right proportions.
Eat more often: bread, rice, potatoes, pasta, and at least five portions of fruit and vegetables a day.
Eat in moderate amounts: meat, fish, eggs and beans, and milk and dairy foods.
Eat less: foods high in fat and/or sugar.
You don't have to give up foods you really like – it's getting the right balance and variety that's important.
The diagram below is known as a food pyramid and shows how to balance your diet; The food groups at the bottom should be eaten most and those at the top eaten least.
Fibre, or more correctly, dietary fibre is known to have very useful properties when eaten regularly and in appropriate amounts. Recent research has shown that dietary fibre is made up of two types, soluble fibre and insoluble fibre. Most foods containing fibre have a combination of these fibre types, although the proportions will vary. Each of the two types are beneficial for people eating them for different reasons, as explained later. They are found only in foods derived from plants such as cereals, bread, vegetables, fruits, legumes and nuts and are associated with the cell walls of plants. They are not present in animal foods, sugar or alcohol.
What is dietary fibre?
A negative definition of 'dietary fibre 'might be 'that part of the diet which cannot be digested by enzymes produced by the body'. This definition doesn't convey any of the positive benefits of dietary fibre, nor does it remind us of the effects of our internal micro-organisms on dietary fibre.
Dietary fibre is basically the indigestible parts of plants but is it not usually fibrous. Because of the problems of definition, scientists use the term 'non-starch polysaccharides'.
The following list defines the solubilities of different fibre types:
- Cellulose - Insoluble.
- Beta-glucans - Soluble, found in barley and oats.
- Pectins - Water soluble and insoluble type are found as part of cell walls. Many fruits are rich in these.
- Hemicelluloses - Sugars, which are soluble in dilute alkali.
- Lignin - Insoluble and resistant to human digestion.
- Resistant Starch - Starch resistant to human digestion.
The following tables and diagrams include information about the health benefits of high fibre diets, fresh weights of foods providing 20 grams of dietary fibre (the minimum daily recommendation) and the major sites of action in the body of soluble and insoluble fibre in relation to heart disease and colon cancer:
Average dietary fibre content per 100g edible portion (g)
So how do you increase fibre in your diet?
- Choose high fibre breads (eg wholemeal, bran, mixed meal, oat bran, and whole-grain varieties, fibre enriched white breads).
- Use high fibre cereals in gravies and casseroles (eg wholemeal flour).
- Add oats, barley, lentils, peas and beans to soups and casseroles.
- Use high fibre breakfast cereals (eg oat flakes, rolled oats, bran flakes, wholegrain oats, milk oaties).
- Sprinkle 1 tablespoon of wheat bran over salads, cereals, into gravies, casseroles etc.
- Choose wholemeal pasta (macaroni, lasagne, spaghetti).
- Leave the skins on fruits and vegetables whenever possible.