Fruits may protect children from leukaemia

US investigators have found that children who ate oranges and bananas or drank orange juice most days of the week before age two were significantly less likely than other children to be diagnosed with leukaemia before age 14.

Previous research has suggested that diet may influence the risk of certain cancers, including colorectal, prostate, lung and breast cancers.

Before age 15, more children become sick from leukaemia than from any other type of cancer. However, the effect of diet on the childhood risk of this cancer remains largely unknown.

To investigate, Dr Marilyn L Kwan of the University of California, Berkeley, and her colleagues interviewed the mothers of 328 children diagnosed with leukaemia and the same number of cancer-free kids. Mothers reported what children ate before age two.

The leukaemia cases and cancer-free children breast-fed for a similar amount of time, and weighed roughly the same at birth.

The researchers found that children who ate oranges or bananas four to six times per week were around half as likely to develop leukaemia before age 14. Drinking orange juice between four and six times per week reduced leukaemia risk by a comparable amount, the team reports in the American Journal of Epidemiology.

Kwan noted that cured meats such as lunch meats and hot dogs contain substances that can become carcinogenic in the stomach, and research in rats suggests that eating these meats in pregnancy may increase the risk of brain tumours in offspring.

However, in this report, eating hot dogs or lunch meats had no influence on leukaemia, perhaps because vitamin C, along with other vitamins contained in fruit, protect the body from the damage the meats can cause, Kwan suggested.

"Perhaps in our study population of California children, child's early consumption of oranges and orange juice, foods which contain large amounts of vitamin C, hindered carcinogenesis," she told Reuters Health.