A study of more than 2,300 Italians has shown that high bread consumption significantly raises the risk of renal cell carcinoma, the most common type of kidney cancer.
Pasta and rice may also raise the risk, but eating vegetables could lower it.
The 12-year study examined 767 adults with this kidney cancer and 1534 who did not have the disease. The researchers asked participants to fill out food frequency questionnaires, which gauged the average weekly consumption for 78 different food items.
There was a significant direct association for bread consumption, and to a lesser extent pasta and rice. A decreased risk was associated with consumption of poultry and all vegetables.
The association between grain products and cancer may be due to the high glycemic index of these foods and their association with insulin-like growth factors.
(Source: International Journal of Cancer October 20, 2006)