Diet and exercise 'cut womb cancer risk'

“Exercise can halve the risk of womb cancer,” the Daily Express reports, while BBC News says the risk could also be reduced by diet, “and possibly drinking coffee”.

The stories are based on a major new report on lifestyle and womb (endometrial) cancer. It concluded that there is convincing evidence that greater body fatness increases the risk of the womb cancer. Physical activity and coffee “probably” protect against womb cancer, the report finds.

The report recommends that women maintain a healthy weight and are physically active for at least 30 minutes a day.

Who produced the report?

The report on endometrial cancer has been produced by the World Cancer Research Fund (WCRF). WCRF is a global charity which funds research on the links between lifestyle and cancer, and raises awareness about how cancer risk can be reduced.

The new endometrial cancer report is part of an ongoing review of the evidence on food, nutrition, physical activity, body fatness, and prevention of womb and other cancers.

What is womb cancer?

Cancer of the womb (uterus) is usually a cancer of the womb lining (endometrium). It is also referred to as endometrial cancer. The most common symptom is abnormal vaginal bleeding.

It is the fourth most common cancer affecting women, with about 8,200 new cases diagnosed each year in the UK. Womb cancer generally affects women who have been through the menopause and is usually diagnosed in women aged over 50.

The cause is unknown, although high levels of the hormone oestrogen increase the risk.

Read more about post-menopausal vaginal bleeding.

What evidence did the WRCF endometrial cancer report consider?

Researchers at Imperial College London collated and reviewed all the scientific research available on womb cancer related to diet, physical activity and body weight, since 2007 (when the last review was carried out). An international panel of experts then carefully judged the evidence.

There were 159 articles on womb cancer included in the review.

What does the WCRF endometrial cancer report say?

The report found that:

• There is “convincing evidence” that greater body fatness (reflected by body mass index, BMI, measures of abdominal girth and adult weight gain) increases the risk of endometrial cancer. 
• A high glycaemic load “probably” increases the risk of endometrial cancer. Glycaemic load is a measure of how much a food raises blood glucose levels.
• Physical activity of all types (including household and recreational) “probably” reduces the risk of endometrial cancer.
• Coffee “probably” reduces the risk, although the report says there is not enough information to recommend drinking coffee as a protective measure.

The report also found evidence other factors may increase risk of endometrial cancer, but that the evidence was too limited to be certain about the link. These include:

• sedentary habits (the time someone spends sitting)

What does the WCRF conclude about reducing womb cancer risk?

In an accompanying press release, the WCRF says that four out of 10 new cases of womb cancer could be prevented in the UK if women were more physically active and a healthier weight.

This figure is based on what would happen if all women in the UK were a healthy weight (BMI of between 18.5 and 25) and physically active for at least 30 minutes a day, seven days a week.

World Cancer Research Fund Executive Director Karen Sadler said: “To reduce the risk of womb and other cancers, World Cancer Research Fund recommends being as lean as possible without becoming underweight and being active for at least 30 minutes every day.

“The evidence on coffee is very interesting and is a further indication of the potential link between coffee and the risk of cancer but a lot more work still needs to be done.”

Scientists believe there are several reasons for the link between body fat and cancer. It is thought that fat cells release hormones that can increase the risk of some cancers. Regular physical activity can help to keep these hormone levels healthy.

Find out more about how to reduce your risk of cancer.

What should I do now?

Regular physical activity and maintaining a healthy weight have established health benefits, including prevention of other cancers.