Drinking 'increases breast cancer risk'

One drink raises the risk by 9% and each further drink up to five causes a similar increase in breast cancer risk - up to 41% greater risk of developing the disease.

The kind of alcohol consumed seemed to have no effect on disease risk.

The researchers at the Harvard School of Public Health in the US cautioned that the arguments for and against drinking were complex:

"Women should weigh the risks of alcohol consumption against other potential benefits: for instance, one to two alcohol-containing drinks has been consistently shown to offer a protective benefit against heart disease."

They concluded, however, that there are other ways to reduce heart disease, like regular exercise and taking aspirin, so reducing alcohol intake makes sense for most women.

More research needed

It is not yet clear what the connection could be between alcohol and breast cancer, though the researchers offered various possibilities.

Alcohol could cause cancer directly, it could hinder the bodies own cancer protection, and it stimulates the release of oestrogen which is known to increase cancer risk.

The report calls for more research looking at overall risk to women from drinking, taking heart disease, traffic and domestic accidents, and other issues into consideration.

Those drinking six drinks a day appeared to have only a 31% higher breast cancer risk, but researchers noted that less than 1% of women sampled drank that much so the results could be due to measurement errors.

The surveys analysed covered 322,647 women from around the world.

High fat diet 'does not promote breast cancer'

Confounding popular wisdom, a survey of nearly 1,600 British women between 50 and 65 found no significant differences in eating habits between those with and without the disease.

"It is unlikely that dietary fat intake has an important influence on breast cancer risk, unless this influence occurs much earlier in life," Dr Janet Cade, who conducted the study, said in the Journal of Epidemiology and Community Health.

The researchers were also puzzled to find that women with high iron intakes seemed to have half the risk of developing breast cancer, although tumours need iron to grow.

An estimated one in 12 UK women will develop the disease sometime in life and it is the leading cause of death for women aged 35 - 54.