Survey shows majority of women are unaware of role of alcohol and obesity in breast cancer

Most women questioned in a survey were unaware that drinking alcohol or being obese could increase their risk of developing breast cancer, according to a Cancer Research UK and Bupa study presented on 2nd November at the National Cancer Research Institute (NCRI) Cancer Conference in Liverpool.

More than a quarter of female breast cancer cases in the UK each year could be prevented largely through lifestyle factors such as keeping a healthy weight and drinking less alcohol*. 

But when researchers gave a questionnaire to 206 women, who were either having a breast screening mammogram or were at a clinic having possible breast cancer symptoms checked out, they discovered that less than a quarter knew that alcohol could increase their breast cancer risk. And even if they did know, at least half of the women didn’t know how much alcohol was in a glass of wine and a pint of beer.**

Researchers also found that less than a third of the women recognised that obesity could increase some people’s risk of developing the disease. And almost a quarter of the women (23 per cent) were unable to name any risk factors for breast cancer at all.***

The study was carried out by researchers at the University of Southampton. They wanted to discover more about how much women already know about breast cancer risk – to help decide whether it might be a good idea to give women advice on ways to reduce risk and help prevent breast cancer at mammogram or clinic appointments.

Every year in the UK, more than 50,000 women are diagnosed with breast cancer and - though survival has doubled in the last 40 years - around 11,600 females die from the disease.

Study co-author Dr Ellen Copson, associate professor of medical oncology, 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,” added Dr Julia Sinclair, Associate Professor of Psychiatry, and the study’s other principal investigator. 

Dr Daniel Rea, chair 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.” 

Notes

* An estimated 27 per cent of female breast cancers in the UK are linked to major lifestyle and other risk factors including overweight and obesity (9 per cent) and alcohol (6 per cent).

** 103 women attending breast screening mammograms (M group) and a further 103 women attending a clinic for women with potential breast cancer symptoms (C group) completed a questionnaire. They were recruited to the study in March 2015.

Alcohol was identified as a risk factor for breast cancer by 16 per cent of the M group, and 24 per cent of the C group. Those who drank alcohol were more likely to identify alcohol as a risk factor than non-drinkers. 50 per cent of the M group and 61 per cent of the C group were unable to correctly identify the alcohol content of any of four alcoholic drinks.

The women were asked to identify the correct number of units in the drinks from a list of possible answers. The correct answers were: A medium glass of wine (12 per cent alcohol by volume (abv) of 175 ml) – 2 units; A pint of beer (4 per cent abv of 586 ml) – 2 units; A one litre bottle of cider (7 per cent abv, 1000 ml) – 7 units; A standard bottle of vodka (40 per cent abv, 700 ml) – 30 units.

*** Obesity was identified as a risk factor by 30 per cent of the M group and 32 per cent of the C group. 23 per cent of each group did not identify any risk factors for breast cancer.

The work was led by Dr Ellen Copson, associate professor of medical oncology, and Dr Julia Sinclair, associate professor in psychiatry, at the University of Southampton. Dr Sinclair is also the clinical lead for Wessex AHSN's Reducing Harm from Alcohol programme.The study was commissioned by Cancer Research UK and Bupa UK.