Dietary habits in adolescence and midlife and risk of breast cancer in older women

Abstract

Recent studies indicate that lifestyle factors in early life affect breast cancer risk. We therefore explored the association of high consumption of meat, milk, and whole grain products in adolescence and midlife, on breast cancer risk. We used data from the population based AGES-Reykjavik cohort (2002–2006), where 3,326 women with a mean age of 77 years (SD 6.0) participated. For food items and principal component derived dietary patterns we used Cox proportional models to calculate multivariate hazard ratios (HR) with 95% confidence intervals (95% CI). During a mean follow-up of 8.8 years, 97 women were diagnosed with breast cancer. For both adolescence and midlife, daily consumption of rye bread was positively associated with breast cancer (HR 1.7, 95% CI 1.1–2.6 and HR 1.8, 95% CI 1.1–2.9, respectively). In contrast, persistent high consumption of oatmeal was negatively associated with breast cancer (0.4, 95% CI 0.2–0.9). No association was found for other food items or dietary patterns that included rye bread. High rye bread consumption in adolescence and midlife may increase risk of late-life breast cancer whilst persistent consumption of oatmeal may reduce the risk.

Long-Term Whole Grain Wheat and Rye Intake Reflected by Adipose Tissue Alkylresorcinols and Breast Cancer: A Case-Cohort Study

“…This potentially occurs through a hormone-dependent mechanism on susceptible epithelium [84], since the risk of ER- breast cancer was not affected. This supports findings in a recent study that daily rye intake during adolescence and midlife is positively associated with breast cancer among post-menopause Icelandic women [85]. However, a previous Danish study [27] on the Danish “Diet, Cancer and Health” cohort did not find any sign of an association between whole grain rye intake (only from FFQ) and risk of breast cancer during the first and second stage of follow-up (Figure 1, median age at entry around 55).…”

Vegetable-Fruit-Soybean Dietary Pattern and Breast Cancer: A Meta-Analysis of Observational Studies

“…However, Terry et al (20) reported that a "healthy" dietary patterns was not associated with breast cancer risk among younger or older women respectively, which usually includes high intake of vegetables, fruits, whole grains and fish. Haraldsdottir et al (45) also reported that high rye bread consumption in adolescence and midlife may increase risk of late-life breast cancer whilst persistent consumption of oatmeal may reduce the risk, which usually includes high consumption of meat, milk, and whole grain products. In contract, several previous studies regarding dietary patterns in relation to breast cancer risk had shown an adverse association with the healthy dietary pattern (19,26,46,47).…”

Milk Intake in Early Life and Later Cancer Risk: A Meta-Analysis

“…To identify additional papers, the reference lists of selected articles and previous systematic reviews were reviewed. After a series of screening, a total of 15 studies (9 studies for breast cancer, 3 studies for prostate cancer, 2 studies for colorectal cancer, 1 study for breast, prostate, and colorectal cancer) were eligible for this meta-analysis [ 2 , 13 , 14 , 15 , 16 , 18 , 19 , 20 , 21 , 22 , 23 , 24 , 25 , 26 , 27 ]. This study selection process is summarized in Figure 1 .…”

“…This premise is corroborated by observations that established risk factors of cancers, such as tallness and early age at menarche, are affected by childhood and adolescent diet [ 11 ]. In fact, calcium and IGF-1 in dairy products play critical roles in development and growth during childhood and adolescence [ 12 ], and several studies have investigated how dairy intake in early life relates to cancer risk [ 2 , 11 , 13 , 14 , 15 , 16 , 17 , 18 , 19 , 20 , 21 , 22 , 23 , 24 , 25 , 26 , 27 ]. However, the results are inconsistent, and no meta-analysis has been conducted yet.…”