Women who have previously had breast cancer are being advised to reduce their alcohol consumption, after research found it could increase the chance of the disease returning.
The study of almost 2,000 women found that just a few alcoholic drinks could increase the risk, with three to four each week creating a 1.3-fold chance of the cancer recurring.
In particular, alcohol proved a greater risk to those who drank two or more glasses of wine a day, or those who were post-menopausal or overweight.
The study found that consuming less than three alcoholic drinks each week had no causal effect.
Chief scientist Dr Marilyn Kwan, from Californian health provider Kaiser Permanente in Oakland, said: "Women previously diagnosed with breast cancer should consider limiting their consumption of alcohol to less than three drinks per week, especially women who are post-menopausal, and overweight or obese."
The findings of the study were presented at a breast cancer conference in San Antonio, Texas.
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