Apples Blueberries are high in antioxidants
Apples are rich in two plant compounds called catechins, and in quercetin. All help to prevent strokes, heart disease and cancer.
Quercetin has also been shown to improve the firmness of collagen, which helps the skin to keep its elasticity. Apples are also rich in the soluble fibre pectin, which helps to lower blood cholesterol.
Lastly, the flesh of apples contains the mineral boron, which helps to prevent calcium loss and provides some protection against osteoporosis.
Avocados contain an amino acid called glutathione, which strengthens your defences against heart disease and cancer. They are also rich in vitamin E, a powerful antioxidant important for good skin condition and wound healing.
Avocados are also a good source of monounsaturated fat, which is linked to lower risk of heart disease.
Whole-grain barley - or "pot barley" - and other whole grains, such as rye and oats, contain phytic acid which has been shown to inhibit the growth of cancers. Barley is particularly rich in chemicals called protease inhibitors, which also have properties that combat cancer, including breast and bowel cancer.
Whole grains are also high in fibre, which helps to keep the digestive and circulatory systems healthy.
Blackcurrants are one of the richest natural sources of vitamin C, at around 130mg per 100g when stewed. Vitamin C is an important antioxidant which helps keep the immune system healthy, keeps the skin in good condition and helps wounds and fractures to heal. High levels of vitamin C are linked with the lowest risk of heart disease.
Blackcurrants also contain other implant compounds such as lutein (see Broccoli) and anthocyanins (see Blueberries), and the oil from their seeds has been shown to have anti-inflammatory effects, relieving arthritic pain. Vitamin C from foods may offer more protection than supplements.
Discovered in recent tests to be the most powerful antioxidants of all, blueberries have the strongest potential to prevent the diseases of old age. It has been found that 100g a day can stimulate the growth of new brain cells and may help prevent memory loss.
Blueberries are also rich in a plant chemical group called anthocyanins, which help oxygenate the skin and keep it looking young. Many other red, purple and blue berries have similar properties.
Broccoli is high in antioxidant carotenoids, vitamin C and indoles, which help fight lung, breast and colon cancers. It is rich in lipoic acid, a fatty acid linked with increased brain power and energy.
As well as high levels of lutein and zeaxanthin, which help keep vision healthy, it's the best vegetable source of vitamin E which is linked with protection against Alzheimer's disease. It is rich in fibre, and a natural source of chromium, which helps to regulate blood sugars.
Read on to learn more about the top healthy foods