Background: The relation between the intake of sugar and sweets and the risk of breast cancer has been considered in ecological, prospective and case-control studies, but the results are unclear. We analyzed such a relation in a case-control study conducted between 1991 and 1994 in Italy.
Patients and methods: Cases were 2569 women with histologically confirmed incident breast cancer and controls were 2588 women admitted to hospital for acute, non-neoplastic, non-hormone-related conditions. Information on diet was based on an interviewer-administered questionnaire tested for reproducibility and validity. The odds ratios (OR) and 95% confidence intervals (CI) were computed by multiple logistic regression equations.
Results: Compared with women with the lowest tertile of intake, women in the highest tertile of intake of desserts (including biscuits, brioches, cakes, puffs and ice-cream) and sugars (including sugar, honey, jam, marmalade and chocolate) had multivariate ORs of 1.19 (95% CI 1.02-1.39) and 1.19 (95% CI 1.02-1.38), respectively. The results were similar in strata of age, body mass index, total energy intake and other covariates.
Conclusions: We found a direct association between breast cancer risk and consumption of sweet foods with high glycemic index and load, which increase insulin and insulin growth factors.