Breast Cancer: Teen Fruit Consumption Linked to Lower Risk
An apple a day may do more than keep the doctor away: A new study looking at fruit and vegetable consumption in teenagers and young adults links higher fruit intake with a lower risk for breast cancer.
In an analysis of prospective data from the Nurses' Health Study II cohort, the consumption of 2.9 servings of fruit per day during adolescence was associated with a 25% reduced risk for breast cancer compared with the consumption of 0.5 servings of fruit daily.
The finding, reported in article published online May 11 in the BMJ by Maryam S. Farvid, PhD, from the Department of Nutrition at the Harvard T.H. Chan School of Public Health in Boston, Massachusetts, and colleagues adds to a growing body of literature suggesting the importance of food choices during adolescence. Earlier this year, Dr Farvid and team reported that women in the highest quintile of fiber intake during early adulthood had a relative risk for breast cancer of 0.81 (95% confidence interval [CI], 0.72 - 0.91) compared with women in the lowest quintile of fiber intake.
The current analysis reflects data from 90,476 premenopausal women aged 27 to 44 years from Nurses' Health Study II who completed a questionnaire on diet in 1991, 44,223 of whom completed an additional questionnaire in 1998 about their diet during adolescence. The investigators looked at total fruit and vegetable consumption during adolescence and early adulthood, and they also looked specifically at intake of fruits and vegetables rich in α carotene in the study population. In addition to breast cancer incidence in the study population, the investigators also considered tumor hormone receptor and menopausal status at diagnosis.
In total, 3235 women developed invasive breast cancer over the course of 22 years of follow-up, including 1347 women for whom adolescent dietary information was available. The researchers assessed fruit intake by quintile. The hazard ratio for breast cancer risk for the highest vs lowest quintile of fruit intake was 0.75, the authors report. "Although women in third and firth category seemed to have a similar lower risk compared with those with the lowest intake, a test for non-linearity was not significant," they write.
"If this apparent risk reduction is applied to lifetime risk of breast cancer, the absolute number of breast cancers that could potentially be prevented by higher intake of fruits would be substantial," the authors explain.
The association for fruit intake during adolescence was independent of fruit intake during adulthood, and there was no association between breast cancer risk and either total fruit intake in early adulthood or total vegetable intake in either adolescence or early adulthood, the authors report.