Overweight middle-aged women could reduce their risk of breast cancer by nearly 40 percent if they shed the pounds, new research reveals.
Postmenopausal women carrying too much weight lower their likelihood of developing the life-threatening condition by 37 percent if they lose 15 percent or more of their body weight, a US study found today.
A loss of five percent or more reduces an overweight woman’s breast cancer risk by 12 percent, the research adds.
This is thought to be due to fat tissue storing the hormone estrogen; high levels of which are linked to breast cancer.
Breast cancer affects around one in eight women at some point in their lives in the US and UK.
Postmenopausal women carrying too much weight lower their risk of developing breast cancer by 37 percent if they lose 15 percent or more of their body weight (stock)
How the research was carried out
Researchers from the City of Hope National Medical Center in Duarte, California, analyzed more than 60,000 postmenopausal women aged between 50 and 79.
Of which, more than 30,000 developed invasive breast cancer over the next 11-to-12 years.
Invasive breast cancer occurs when part of the disease has grown in breast tissue and part has stayed in milk ducts.
All of the participants had a normal mammogram and no prior breast cancer. Their height and weight was measured.
At the beginning of the investigation, 41 percent of the women were a normal weight, 34 percent were overweight and 25 percent were obese. None of the women were underweight.
Weight loss reduces breast cancer risk by up to 37%
Results reveal overweight women who lose five percent or more of their body weight are 12 percent less likely to develop breast cancer.
A weight loss of 15 percent or more reduces an overweight woman’s cancer risk by 37 percent.
Lead author Professor Rowan Chlebowski said: ‘Relatively modest weight loss was associated with significant lowering of breast cancer incidence.
‘From this study, we have evidence that a weight-loss strategy can be effective in lowering breast cancer risk in postmenopausal women.’
The findings also show a weight gain of five percent or more is linked to an over 50 percent increased risk of developing triple-negative breast cancer, which affects around 15 percent of sufferers and is resistant to common treatments.
The findings were presented at this year’s San Antonio Breast Cancer Symposium.
Experts say we can all reduce our breast cancer risk by keeping physically active (stock)
‘We can all reduce our breast cancer risk through lifestyle’
Baroness Delyth Morgan, chief executive at Breast Cancer Now, said: ‘This important study provides further, clear evidence that postmenopausal women can significantly reduce their risk of breast cancer by taking steps to lose weight.
‘Being overweight after the menopause does increase your risk of the disease, likely because fat tissue becomes a women’s main source of estrogen after the menopause.
‘The less body fat you have, the lower your estrogen levels, which can decrease your breast cancer risk.
‘With breast cancer incidence continuing to rise, we need to do much more to enable women and men of all ages to reduce their risk.
‘It’s so important to remember that we can all reduce our breast cancer risk through various lifestyle factors, including keeping physically active, maintaining a healthy weight throughout life and lowering our alcohol intake.’