Peppers, sweetcorn, yellow pumpkins, grapefruit, lemons, pineapples.

Why? For carotenoids. Yellow fruit and veg are also good sources of two yellow compounds, lutein and zeakanthin, which are major pigments in the eye. Studies show that those who eat more of these compounds have a lower risk of developing age-related macular degeneration (AMD), a common cause of blindness in later life. Another compound, this time found in the rinds of citrus fruits, is limonene, a compound that boosts liver enzymes involved in detoxifying cancer-causing chemicals.

Carrots, peppers, sweet potatoes, butternut squash, apricots, mangoes.

Why? Carotenoids are key ingredients of orange fruit and veg. Other important ingredients include bioflavonoids, chemical compounds that, according to research, decrease inflammation and work to stop or slow the development of cancer, heart disease and neurodegenerative diseases, such as Alzheimer's. Bioflavonoids also act as natural antibiotics and help to prevent against food poisoning. Carotenoids are best absorbed in the presence of fat, so flavour cooked carrots with a dash of walnut, olive or sesame oil.

Beetroot, red onions, red potatoes, peppers, rhubarb, tomatoes, cherries.

Why? For Iycopene, a powerful carotenoid found in red, orange and yellow fruit and veg. Carotenoids are turned into the antioxidant vitamin A in the body, which helps to guard against damage by free radicals. Also, good communication between cells is vital to halt cancer, and carotenoids appear to enhance this. Several studies have shown that Iycopene may protect against prostate cancer. Red fruit and veg are also a source of anthocyanins.

Tomatoes are richest in Iycopene if cooked, so go for sauces and purees.