Women take extreme diet to help Breakthrough Breast Cancer scientists make important discovery about weight and breast cancer risk

Ten women took an extreme 900 calorie-a-day diet to help Breakthrough Breast Cancer scientists make an important discovery about the link between weight and breast cancer risk, published online in the journal Cancer Prevention Research today (Wednesday 5 August).

The overweight or obese women, in their 30s and 40s and at increased risk of breast cancer due to their family history of the disease, were asked to follow the diet for one month. They were compared at the end of this period with nine women with a similar family history of breast cancer who stuck to a normal diet of around 2,000 calories a day.

The scientists, led by Professor Anthony Howell, discovered that the women who had followed the diet had reduced expression of a gene called SCD within their breast tissue. This gene has been shown to be linked to cancer growth. This is the first time a change like this has been observed in the breast tissue. Their findings could provide a vital clue to how losing weight may help reduce breast cancer risk in this group of women.

Professor Anthony Howell, Director of the Breakthrough Breast Cancer Research Unit at the University of Manchester, said: “The women who took part in this study made a major commitment to help us carry out this vital research. 

“They enabled us to look for the first time at changes that occur within the breast tissue that may make cancer growth less likely. These results now need to be tested in larger groups of women over longer periods of time.”

It is hoped that, if results continue to be promising, experts could be able to recommend specific changes of diet to women at higher risk of breast cancer so they can reduce their likelihood of developing the disease.

Dr Alexis Willett, Head of Policy at Breakthrough Breast Cancer, said: “We already know that the more weight a woman gains over the course of her adult life, the higher her risk of developing breast cancer will be after she has gone through the menopause. However, it is important to find out more about how lifestyle changes like losing weight can affect breast cancer risk.

“We wouldn’t advise women to follow a diet of this kind as those who took part were closely monitored by a specialist dietician. We do recommend that women maintain a healthy weight to reduce their breast cancer risk.”

Breakthrough Breast Cancer’s research is funded almost entirely by voluntary donations. For more information about Breakthrough Breast Cancer’s research and how to support the charity, visit breakthrough.org.uk or call 08080 100 200.