Eating five or more daily servings—which equates to a cup of raw leafy vegetables or half-a-cup of raw or cooked vegetable or fruit—reduces the risk by 11 per cent compared to women who eat less.
Broccoli and yellow and orange vegetables have the greatest protective effect against breast cancer, and especially the aggressive form that can be life-threatening.
A high fibre intake was once thought to be the best way to protect against cancer, but researchers from the Harvard T H Chan School of Public Health, who carried out the latest analysis, say that the antioxidants and other micronutrients found in vegetables and fruit were equally as important.
The researchers analysed data gleaned from questionnaires prepared by nearly 94,000 women who had participated in the Nurses' Health Study. Not only did five or more daily servings of fruit and vegetables reduce the overall risk for breast cancer, they also protected against a more aggressive type of breast cancer.