Increased fiber intake, especially during adolescence and early adulthood, it seems to reduce the risk of breast cancer, according to a study published recently in Pediatrics.
The associations are evident for most of the sources of fiber and are independent of other dietary and other healthy eating behaviors factors.
The prospective study included a study of nurses aged between 25 and 42 years old at the time of registration of their course at Harvard University since 1989.
The largest cohort had 90.534 premenopausal women who completed a dietary questionnaire in 1991 and 44,263 women who completed a questionnaire in 1998, which asked them to recall their diet in high school. The researchers assessed in particular the importance of timing of fiber intake on the risk of breast cancer before menopause. They then evaluated the association between fiber intake during certain periods of life (adolescence, early childhood, and premenopausal in general) and the risk of breast cancer. The researchers found an inverse association between the consumption of most of the sources of fiber and the incidence of breast cancer. In particular, when women in adulthood in the highest quintile of fiber intake were compared with those of the lowest quintile of fiber intake, the relative risk of breast cancer was 0.81. When the analysis was performed for the average fiber intake during adolescence and early adulthood, the highest relative risk vs lowest quintile of fiber consumption was 0.75.
Recently, several studies have suggested that dietary fiber may be protective against breast cancer, although the effect was documented in previous studies, in general, small. The current study is distinctive in that it is specifically examined the diet during adolescence or early adulthood and in relation to these eating habits for the late tumors.
Taken together, the studies suggest that fiber is a potentially modifiable risk factor for breast cancer. The consumption of fiber can be especially important during adolescence or early adulthood, when the breast cancer risk factors seem to be particularly important.
The researchers suggest in their discussion that dietary fiber may reduce the risk of breast cancer, improving insulin sensitivity and decreasing insulin-like growth factors.
In particular, the association between dietary fiber and the weight must be examined prospectively to understand the clinical impact of the results of the authors. It is reasonable that pediatricians encourage the use of a high-fiber diet and understand to decrease the risk of breast cancer.