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.

Cancer Prevention Research

The paper entitled, ‘Biomarkers of dietary energy restriction in women at increased risk of breast cancer’, is published in Cancer Prevention Research, a journal of the American Association for Cancer Research (AACR).

Family history of breast cancer

Having a family history of breast cancer means having an unusually high number of close relatives with breast cancer. Often these relatives have been diagnosed when younger than would normally be expected.

Having one relative who was diagnosed with breast cancer over the age of 50 would probably not count as a family history. Four out of five breast cancers occur in families without a significant history of the disease. 

Professor Anthony Howell

Professor Anthony Howell is Professor of Medical Oncology at The University of Manchester based at the Christie Hospital and University Hospital of South Manchester (Genesis Prevention Centre).  He is also the R & D Director of the Christie Hospital. He is Head of the Manchester Breast Centre and the new Breakthrough Breast Cancer Research Unit.  His major interest is in the biology, prevention and treatment of breast cancer.  He has published, with his colleagues, over 450 research papers mainly related to the breast and its diseases.

Dr Michelle Harvie, dietician

Dr Michelle Harvie was the dietician who worked with the women who took part in this study. She is sponsored by The Genesis Appeal – the UK’s only charity dedicated to the prevention of breast cancer. She is the UK’s only research dietician studying the link between lifestyle and breast cancer as a means of preventing the disease. She works solely in the field of breast cancer research.

Breakthrough Breast Cancer

Breakthrough Breast Cancer is the UK’s leading charity committed to fighting breast cancer through research, campaigning and education. In 1999 Breakthrough established the UK’s first dedicated breast cancer research centre. The Breakthrough Toby Robins Breast Cancer Research Centre is housed in the Mary-Jean Mitchell Green building at The Institute of Cancer Research in association with the Royal Marsden Hospital.

Breast Cancer

• Breast cancer is the most commonly diagnosed cancer in the UK – nearly 46,000 women and around 300 men are diagnosed every year.
• 15-20% of all breast cancers are HER2 positive. These tumours have a more aggressive clinical behaviour and can be treated with agents targeting HER2.
• Breast cancer accounts for nearly 1 in 3 of all female cancers and one in nine women in the UK will develop breast cancer at some point in their lifetime.
• The good news is that more women than ever in the UK are surviving breast cancer thanks to better awareness, better treatments and better screening.

For further information about Breakthrough or breast cancer please visit breakthrough.org.uk or call the charity’s free information line on 08080 100 200.