Calorie-restricted starch-fed rats had poorer early life survival, and no significant increase in mean life span compared to ad libitum cornstarch-fed animals (726 vs 720 days). These animals did, however, have the greatest upper 10th percentile survival of all four experimental groups. Mean life span of calorie-restricted sucrose-fed rats was significantly greater than that of all other groups (890 +/- 18 days).

RESULTS: There was no association between breast cancer risk and intake of calories, macronutrients, or types of fat. Risk of breast cancer was unrelated to intakes of a variety of food groups, including red meats, dairy, high-fat snacks and desserts, or foods high in animal fat. Increased risk was observed for high intake of a food group composed of sweet items, particularly sodas and desserts. Risk increased linearly with percent of calories from sweets and frequency of sweets intake. Consumption of sweets 9.8 or more times per week compared with <2.8 times per week was associated with an adjusted OR of 1.32 (95% CI = 1.0-1.8).

FINDINGS: The risk of breast cancer decreased with increasing total fat intake (trend p 0.01) whereas the risk increased with increasing intake of available carbohydrates (trend p = 0.002). The odds ratios for women in the highest compared with the lowest quintile of energy-adjusted intake were 0.81 for total fat and 1.30 for available carbohydrates. Starch was the chief contributor to the positive association with available carbohydrates. High intakes of polyunsaturated and unsaturated fatty acids (i.e., polyunsaturated fatty acids plus oleic acid) were associated with a decreased risk of breast cancer (odds ratios for highest vs lowest quintile 0.70 and 0.74, respectively). Conversely, the intakes of saturated fatty acids, protein, and fibre were not significantly associated with breast-cancer risk.