Breast cancer might not result merely from genetic quirks. Unhealthy lifestyles too could provoke it.
Modern lifestyles which feature regular drinking, lack of exercise and increased obesity are fuelling the rise of the disease, the European Breast Cancer Conference heard Friday.
Up to a third of breast cancer cases could be avoided if women ate less and exercised more, it has been claimed.
Carlo La Vecchia of Milan University told the conference in Barcelona: 'What can be achieved with screening has been achieved. It's time to move on to other things.'
Dr La Vecchia said the International Agency for Research on Cancer estimates that 25 to 30 per cent of cases could be avoided if women were thinner and did more exercise.
Carlo La Vecchia is an Italian epidemiologist. He is doing research on chronic diseases, where he contributed to the understanding of the risks related to diet, tobacco, oral contraceptive use and occupational or environmental exposure to toxic substances in cancer and other chronic diseases development.
The World Cancer Research Fund has noted, citing World Health Organisation, "At least 60 per cent of world's population does not achieve the minimum recommendation for physical activity...
"There is convincing evidence that being physically active protects against bowel cancer and also against obesity.
"Being physically active also probably protects against cancers of the breast (post menopause) and endometrium. Obesity alone is linked to a number of cancers including bowel, oesophagus, pancreas, kidney, endometrium and breast (post menopause).
"Physical inactivity is estimated to cause 2 million deaths worldwide annually. The prevalence of physical inactivity in adults globally is 17 per cent (range 11 to 24 per cent). The highest rates of inactivity were in European WHO member States with low child and high adult mortality (e.g. Hungary, Latvia, Russian Federation and Ukraine) and the lowest rate of inactivity was in a high mortality region of Africa (e.g. Congo, Ethiopia, South Africa, Uganda, Zimbabwe).
"An estimate of the prevalence globally of some, but insufficient activity (<2.5 hours per week of moderate activity) is 41 per cent (range 31 to 51 per cent).
"Physical activity declines with age, and starts to decline from adolescence. Inactivity tends to be higher among girls and women."
The outfit recommends, "Be moderately physically active, equivalent to brisk walking, for at least 30 minutes every day.
As fitness improves, aim for 60 minutes or more of moderate, or for 30 minutes or more of vigorous, physical activity every day.
Limit sedentary habits such as watching television.
Studies show drinking one large glass of wine a day increases the chances of developing the disease by a fifth, say experts. That could be linked to alcohol raising levels of oestrogen.
Dr Rachel Thompson said the WCRF had reviewed 954 separate studies.
"The evidence is now convincing that drinking alcohol, being physically inactive and having excess body fat all increase risk of breast cancer," she said.
"There is also convincing evidence that breastfeeding reduces the mother's risk of breast cancer. Overall, we estimate about 40 per cent of breast cancer cases in the UK could be prevented through these lifestyle factors."
But Robert Baan, an expert with the International Agency for Research on Cancer, said it was not clear if already overweight women could lower their cancer risk by slimming down or if long-term damage had already been done.
Michelle Holmes, a cancer expert at Harvard University, said people might wrongly think their chances of getting cancer are more dependent on their genes than their lifestyle.
"The genes have been there for thousands of years, but if cancer rates are changing in a lifetime, that doesn't have much to do with genes,'' she said in a phone interview.