Salad fans may have lower risk of kidney cancer

Women keen on bananas, salads and root vegetables may be less likely to develop kidney cancer, suggests a new Swedish study.

Researchers at the Karolinska Institutet in Sweden analysed dietary information from 61,000 women aged 40-76 and followed the group for 13 years.

They found that those who consumed five or more servings of fruit and vegetables daily reduced their relative risk of developing renal cell carcinoma - the most common form of kidney cancer - although these results were not statistically significant.

However certain fruits and vegetables - namely bananas, root vegetables, white cabbage and salad veg - appeared to offer strong protection, report the authors in the 20 January issue of the International Journal of Cancer (vol 113, issue 3, pp451-5).

Eating salads more than once a day decreased the risk by 40 per cent in comparison to no consumption, while women who ate bananas four to six times a week had about half the risk of kidney cancer as those who did not eat the fruit.

Bananas are rich in potassium, the anti-carcinogenic potential of which has been speculated upon by epidemiologists.

Regular consumption of root vegetables like carrots was linked to a 50- 65 per cent decrease in risk.

The number of people being diagnosed with kidney cancer has increased sharply over the past 20 years. Almost 6,000 people in the UK are told they have the disease each year.

However, rates are much higher in western countries than they are in developing countries leading scientists to suspect that lifestyle factors, such as smoking and obesity, play an important role.

There is some previous evidence to show that regularly eating fruit and vegetables may protect against kidney cancer but the data has not been consistent.

The new study is the largest to show an association between kidney cancer and fruit and vegetable intake, according to lead author Dr Bahram Rashidkhani.

The study follows a major review of evidence to date on fruit and vegetable consumption and breast cancer risk, finding that it is insufficient to support any protective effect.