Most women undergoing checks for breast cancer are unaware that drinking alcohol or obesity increases their risk of the disease, a poll has found.
The survey of 206 women having a breast screening mammogram or being checked over for symptoms at a breast clinic found fewer than a quarter knew that alcohol could increase their breast cancer risk.
Of those who did know, at least half of the women were unaware how much alcohol was in a glass of wine and a pint of beer.
Researchers also found that fewer than a third of women knew obesity could increase chances of the disease, while 23% were unable to name any risk factors for breast cancer at all.
The research, from Cancer Research UK and Bupa, is being presented at the National Cancer Research Institute (NCRI) Cancer Conference in Liverpool.
According to Cancer Research UK, more than a quarter of breast cancer cases in the UK each year could be prevented through women leading healthier lifestyles, such as keeping a normal weight and drinking less alcohol.
It is estimated that 9% of all cancer cases in the UK among women are linked to overweight and obesity, while 6% are linked to alcohol.
Every year in the UK, more than 50,000 women are diagnosed with breast cancer and around 11,600 die from the disease.
Study co-author Dr Ellen Copson, associate professor of medical oncology at the University of Southampton, said: "There are ways women can potentially reduce their breast cancer risk - including drinking less alcohol and keeping a healthy weight. But most of the women we questioned didn't know this.
"It's also worrying that so few of the women we questioned knew how much alcohol was in various drinks.
"The more alcohol you drink, the more your risk of breast cancer increases - but making a decision about whether or how to cut back is more difficult if women aren't sure about the alcohol content of different drinks."
Dr Daniel Rea, chairman of the NCRI breast cancer clinical studies group, said: "This study highlights that women aren't always aware that lifestyle changes can have an impact on breast cancer risk.
"We need to find the best time and place to provide this information and use these opportunities to help women know what choices can be made to cut their chances of developing the disease."
A medium (175ml) glass of wine (12% alcohol by volume) contains two units of alcohol. A pint of beer (4%, 586ml) is also two units.