An apple a day helps keep cancer at bay

Apples are richer in anti-cancer chemicals than expensive dietary supplements, a new study reveals, lending weight to the saying: an apple a day keeps the doctor away.

Apples are richer in anti-cancer chemicals than expensive dietary supplements, a new study reveals, lending weight to the saying: an apple a day keeps the doctor away.

Extracts from fresh apples were found to retard the growth of cancer cells in a test tube. Scientists also found that apples are 15 times richer in antioxidants - which are thought to prevent cancer - compared with pure vitamin C.

Antioxidants prevent the action of highly destructive chemicals called free radicals, which can damage the structure of DNA, triggering the cancerous growth of cells.

Food scientists led by Rui Hai Liu, from Cornell University in Ithaca, New York, write in the journal Nature today: "Our results indicate that natural antioxidants from fresh fruit could be more effective than a dietary supplement."

The scientists calculated that 100 grams (3.5oz) of fresh apples had an antioxidant activity equivalent to 1,500 grams of pure vitamin C, one of the strongest antioxidants in food supplements.

Extracts from the red delicious variety of apples also inhibited the growth of liver and colon cancer cells in the laboratory. The degree of inhibition depended on the concentration of the extract, showing that the effect was genuine rather than a coincidence.

Apples with the skin proved far more effective than those without, indicating that most of the antioxidant activity was due to the skin's phytochemicals - substances produced by plants such as phenolic acids and flavonoids - rather than to the vitamin C in the fruit.

Extracts from apples with skin inhibited cancer cell growth by 43 per cent compared with 29 per cent for extracts from skinless apples.