Women may have a reduced risk of developing breast cancer if they consumed a lot of fruit as a teenager.

While fruit and vegetables are thought to help protect against breast cancer, studies have provided conflicting results. However most of these studies have looked at fruit consumption during midlife or even later, so US researchers decided to look at younger people.

They followed the progress of 90,000 nurses for more than 20 years, half of whom provided details about their diet during adolescence.

The study found that those who had consumed high levels of fruit during adolescence had a 25% reduced risk of being diagnosed with breast cancer in middle age.

The researchers noted that in particular, a higher consumption of bananas, apples and grapes as a teenager, as well as oranges and kale in early adulthood, were linked with a reduced risk of the disease.

However, drinking fruit juice during adolescence or early adulthood did not reduce the risk.

While people are already advised to eat more fruit and vegetables to reduce their risk of cancer overall, the researchers from Harvard pointed out that this may be particularly important during adolescence.

Details of these findings are published in the British Medical Journal.