Fruit and vegetables are low in energy and packed with vitamins, minerals, protective plant compounds and fibre, so they're a great source of nutrients and vital for a healthy diet.

Five a day

Due to their nutritional and health benefits, it's recommended that fruit and vegetables form the basis of your diet, with a minimum intake of five portions each day - about a third of your daily food consumption. Currently the UK averages two to three portions a day, so we're falling well short of the benefits they can provide.

Fruit and vegetables should be incorporated into every meal, as well as being the first choice for a snack. Population studies have shown that people who eat a lot of fruit and vegetables may have a lower risk of chronic disease, such as heart disease and some cancers. Health benefits can be gained from fresh, tinned (in natural juice), frozen, cooked, juiced or dried versions. Potatoes don't count though, as they're a starchy food.

How much is a portion?

• One piece of medium-sized fruit, such as an apple, peach, banana or orange
• One slice of fruit, such as melon, mango or pineapple
• One handful of grapes or two handfuls of cherries or berry fruits
• One tablespoon of dried fruit
• A glass (roughly 100ml) of fruit or vegetable juice
• A small tin (roughly 200g) of fruit
• 3 tablespoons of fruit salad or stewed fruit
• A side salad
• A serving (roughly 80g) of vegetables, such as frozen or mushy peas, boiled carrots or stir-fried broccoli
• Cooked dishes that contain significant amounts of vegetables may also count

So how do you ensure an intake of five portions a day? Here's a typical plan:

• Glass of fresh orange juice or smoothie for breakfast = one portion
• Small pack of dried apricots for mid-morning snack = one portion
• Side salad with lunch = one portion
• Sugar snap peas and broccoli, served with main meal = one portion
• Strawberries as dessert = one portion

Do remember that some fruits contain many of their nutrients just under the skin, so eating them with the skin on can provide greater nutritional benefits and the maximum amount of fibre compared with just drinking the juice of the same fruit.

Why are they important?

Fruit and vegetables of differing colours contain diverse mixtures of phytonutrients (protective plant compounds). These can act as powerful antioxidants, protecting the body from harmful free radicals and helping to protect against certain chronic diseases such as cancer. Some fruit and vegetables are labelled as 'superfoods' because they contain high concentrations of some phytonutrients, particularly antioxidants, which appear to be beneficial to health.

• Blueberries - contain flavonoids that can improve circulation and help defend against infection
• Broccoli - rich in the antioxidants vitamin C and beta-carotene, as well as folate, all of which can protect against cardiovascular disease and cancer
• Tomatoes - rich in lycopene, a powerful antioxidant that can protect against harmful free radicals
• Linseeds - rich in omega-3 fatty acids, which may help control cholesterol levels

But variety is the key. In addition to these phytonutrients, each variety of fruit and vegetables contains its own combination of vitamins, minerals and fibre. Choosing a variety throughout the day will provide a diverse package of essential nutrients.

Boiled or steamed?

Although fruit and vegetables are packed with vitamins and minerals, many of these essential nutrients can be easily destroyed by heat when cooking and during food preparation. Water-soluble vitamins are especially vulnerable when boiled. One solution is to eat raw vegetables as much as possible, such as raw carrot, celery or peppers.

When cooking vegetables, try steaming, microwaving or poaching rather than boiling. These methods do not involve immersing them in water, so the maximum amount of nutrients can be retained, as well as their fresh taste. If you prefer to boil vegetables, do so for the minimum amount of time and in as little liquid as possible in order to retain their valuable nutrients. You could also utilise the water used in another part of your dish, such as gravies or stocks, to recapture some of the leached nutrients.

Fibre for weight control?

Fruit and vegetables are important contributors to the intake of dietary fibre, both soluble and insoluble. Fibre is slowly digested and has a low Glycaemic Index (GI). This means glucose will be released steadily into the body over several hours, allowing you to feel fuller for longer, compared with high GI foods that produce a rapid rise followed by a subsequent fall in blood sugar, often leaving you hungry soon after you've eaten. This feeling of fullness produced by the fibre within fruit and vegetables can therefore help with weight control. Fruit and vegetables also assist weight management as they're low in calories, but remember that their calorific load is determined by what you prepare them with, so avoid the butter, cream or cheese sauces, and dips that can accompany them.

This article was last medically reviewed by the MRC Human Nutrition Research in July 2008. First published in March 2001.