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People who flavour their diets with plenty of onions and garlic may be reducing their chances of getting several types of cancer, a study suggests.
In an analysis of eight studies from Italy and Switzerland, researchers found that older adults with the highest onion and garlic intakes had the lowest risks of several cancers - including colon, ovarian and throat cancers.
The findings, which appear in the American Journal of Clinical Nutrition, are in line with some previous research. But most of those studies were done in China, and it is not known if the results are different in Western countries.
And it is still not certain that onions and garlic have a direct effect on cancer risk. It's possible, for instance, that onion and garlic lovers also have an overall diet that protects against cancer, say researcher Carlotta Galeone and her colleagues.
On the other hand, they note, animal studies and lab experiments with cancer cells have found that compounds in onions and garlic may inhibit the growth of tumours.
Sulphur compounds found in garlic and antioxidant flavonoids in onions are among the potentially protective substances.
Each of the Italian and Swiss studies compared healthy older adults to patients with a particular form of cancer, asking participants for detailed information on their diets, physical activity and other lifestyle habits.
Dr Galeone's team found that men and women who ate seven or more servings of onions a week had less than half the risk of those who shunned the vegetable of contracting colon cancer. Garlic lovers were 25 per cent less likely to develop the disease than people who maintained garlic-free diets.
The vegetables were also linked to lower risks of cancers of the mouth, throat, kidneys and ovaries.
But Dr Galeone suggests that while onions and garlic may be beneficial, it's best to mix them with plenty of other vegetables.
Some research has found that garlic and tomatoes may have "synergistic" cancer-fighting effects, she and her colleagues note.
And, in general, experts recommend that people eat a variety of fruits and vegetables every day for overall health.
- REUTERS
