Walnuts lower tumour rates in cancer-prone mice
A study presented at the American Association of Cancer Research conference showed that specially bred 'cancer-prone' mice fed the equivalent of two ounces of walnuts every day have lower breast tumour rates than mice fed a normal diet.
The results suggest that chemicals found in walnuts might be useful in protecting against cancer, although a Cancer Research UK spokesperson pointed out that the study was too small to draw any firm conclusions.
In the study, carried out by Dr Elaine Hardman, associate professor of medicine at Marshall University School of Medicine, and her team, breast cancer-prone mice were given either a control diet or one containing the equivalent of two ounces of walnuts every day.
Walnut consumption helped to lower the number of mice who developed at least one breast tumour, and decreased tumour size in mice who did develop cancer.
Commenting on the US team's findings, Josephine Querido of Cancer Research UK emphasised that as the study was in mice, "we have no evidence to say that a daily handful of walnuts may prevent breast cancer in humans".
Ms Querido explained that it is not yet possible to isolate a particular food that can reduce the risk of breast cancer in humans. "When it comes to our diets, there is no one food in particular that will help protect you from cancer," she commented.
"But we know that a healthy balanced diet - rich in fruit and vegetables - plays an important part in reducing the risk of many types of cancer.
"The strongest risk factor for breast cancer is age - 80 per cent of breast cancers occur in women over the age of 50 so attending screening is important. Making lifestyle changes, such as keeping a healthy body weight, limiting alcohol intake and taking regular exercise, can also help reduce breast cancer risk."