All foods, even battered Mars bars, have some nutritional value. But there are 10 that are so beneficial to your health they are known as 'super foods'. Check them out here:
Over 7,500 varieties of apple are grown throughout the world. They are packed full of antioxidants, especially vitamin C for healthy skin and gums - one apple provides a quarter of your daily requirement of vitamin C.
Apples also contain a form of soluble fibre called pectin that can help to lower blood cholesterol levels and keep the digestive system healthy.
An apple is also a carbohydrate with a low glycaemic index (GI) type.
Low GI foods are digested slowly; once they are finally broken down in the intestine they are gradually absorbed into the bloodstreams as glucose, causing a gradual rise in blood sugar levels.
They may help with weight control, as well as improving diabetics' long-term control of blood sugar levels.
2. Baked beans
The humble baked bean is a nutritional powerhouse of protein, fibre, iron and calcium. It contains carbohydrate that, like that in apples, is of the low GI variety.
The tomato sauce covering baked beans is also a good source of lycopene, another powerful antioxidant shown to help prevent heart disease and prostate cancer.
The insoluble fibre in baked beans is not digested but moves into the large intestine, or colon, where bacteria act on it and produce short-chain fatty acids.
These fatty acids are thought to nourish the colon lining and protect it from carcinogenic (cancer-causing) invaders.
Just two florets - raw or lightly cooked - count as a veggie portion.
Not only does broccoli contain antioxidants including vitamin C but it's a particularly good source of folate (naturally occuring folic acid).
Increasing your intake of folic acid is thought to be of major benefit in preventing heart disease.
Broccoli also contains an antioxidant called lutein that can delay the progression of age-related macular degeneration (AMD). This affects 10 per cent of people over 60 and is a major cause of impaired vision and blindness.
Finally, broccoli also contains a phytochemical called sulphoraphane that has specific anti-cancer properties.
4. Olive oil
Several large studies suggest that the monosaturated fat in olive oil is good for the heart. Olive oil lower bad cholesterol levels and increases the good levels.
Olive oil is also rich in antioxidants - it's probably one of the key protective aspects of the so-called Mediterranean diet.
Watch out for the calories - a little goes a long way. A tablespoon of oil contains 120 kilocalories, which is the same as a large slice of bread and butter.
5. Wholegrain Seeded Bread
Breads containing a lot of seeds and wholegrain have a low GI, which can protect against heart disease, reduce hunger pangs, and help with weight control.
They are also packed with fibre, which keeps the gut working efficiently; and seeded breads contain essential fatty acids.
Studies show that including four flices of soya and linseed bread a day can give a does of phytoestrogens, through to relieve "hot flushes" in menopausal women.
The downside is that bread contains a lot of salt. However, the good news is that bread manufacturers have started to use less salt in their pre-packaged bread.
All fish is a source of good-quality protein, vitamins, and minerals, but oily fish such as salmon also contains omega 3 fats that reduce blood clotting and inflammation.
Studies show that eating oily fish dramatically recues the risk of having a heart attack, even in older adults.
Omega 3 fats also help to prevent depression, and protect against the onset of dementia. Yep, it's true, fish really is an all-round brain food.
The drink loved by all Britons has a range of useful properties. The caffeine content is helpful for stimulating alertness, mood and motivation.
Tea counts towards the recommended eight cups of fluid daily, which is the minimum to avoid dehydration.
Tea, whether black or green, is a rich source of the antioxidant called catechins. Studies suggest that catechins protect the artery walls against the damage that causes heart disease and prevents formation of sticky blood clots.
Some population studies suggest as little as one cuppa a day seems to offer some protection.
Yogurt is an easily absorbed source of calcium. It's also a useful milk subsitute for people who can't digest large amounts of the milk sugar, lactose.
Yogurt has long been credited with a range of therapeutic benefits, many of which involve the health of the large intestine and the relief of gastrointestinal upsets.
The bacteria Lactobacillus GG, added to some yoghurt, are not digested, and reach the large intestine intact where they top up the other friendly bacteria living there.
The friendly bacteria fight harmful bacteria, including Clostridium difficile that can cause diarrhoea after a course of antibiotics.
It's a myth that bananas are fattening. Bananas are slightly higher in energy than other fruits but the calories come mainly from carbohydrate; excellent for refuelling before, during or after exercise.
All types of fruit and vegetables contain plant chemicals or phytochemicals known as antioxidants. These antioxidants protect cells in the body against damage from free radicals that can cause heart disease and cancer.
Bananas are also jam-packed with potassium that helps lower blood pressure, and vitamin B6 for healthy skin and hair.
10. Brazil nuts
All nuts are generally full of essential vitamins, minerals and fibre. Recent studies suggest that eating a small handful of nuts four times a week can help reduce heart disease and satisfy food cravings.
Brazil nuts are one of the few good sources of selenium that may help protect against cancer, depression and Alzheimer's disease.