Fruit and alcohol - the effect on breast cancer risk
13 May 2016
Two major studies have shed new light on the relation of alcohol and diet with breast cancer and heart disease.
One reports that high fruit consumption during adolescence may be associated with reduced breast cancer risk. The other shows that increasing alcohol intake in later life is associated with an increased risk of breast cancer.
Fruit and vegetables are thought to protect against breast cancer, but the evidence is conflicting. Most studies have assessed intakes during midlife and later, which may be after the period when breast tissue is most vulnerable to carcinogenic influences.
But a team of Harvard researchers followed 90,000 nurses for over 20 years and found that high fruit consumption during adolescence (2.9 v 0.5 servings per day) was associated with a roughly 25% lower risk of breast cancer in middle age.
In particular, greater consumption of apple, banana and grapes during adolescence, as well as oranges and kale during early adulthood was significantly associated with a reduced breast cancer risk, they report in The BMJ.
But there was no link between intake of fruit juice in either adolescence or early adulthood and risk.
In the alcohol study published in The BMJ, Danish researchers tested the effect of a change in alcohol intake on the risk of breast cancer and heart disease.
They followed the health of nearly 22,000 postmenopausal women in Denmark and found that those who increased their alcohol intake by 2 drinks per day had around a 30% increased risk of breast cancer but around a 20% decreased risk of coronary heart disease, compared with women with a stable alcohol intake.
However, a reduction in alcohol intake over the 5-year period of the study was not significantly associated with reduced risk of breast cancer or coronary heart disease.
2. Five year change in alcohol intake and risk of breast cancer and coronary heart disease among postmenopausal women: prospective cohort study
Alcohol, diet, and risk of breast cancer