Ketogenic Ratio of Macronutrients and Risk of Diabetes Among Postmenopausal Women

OBJECTIVES: To evaluate the association of the ketogenic ratio of macronutrients (KR) with incidence of diabetes (DM). METHODS: Dietary information was obtained at baseline from postmenopausal women enrolled in the Women's Health Initiative (WHI) clinical trials (not including the intervention arm of dietary modification trial) and observational study. Participants were excluded if they had prevalent diabetes or unknown status of diabetes at baseline or reported energy intakes 5000 kilocalories. The KR was calculated as follows: (0.9*grams fat + 0.46*grams protein) divided by (0.1*grams fat + 0.58*grams protein + grams total carbohydrate – grams total fiber). A KR value 1.5 is considered the minimum threshold to predict a ketogenic diet. Cox proportional hazards models were used to estimate hazard ratios (HRs) and 95% confidence intervals (CIs) for associations between KR and risk of DM. Follow-up time was the number of days from enrollment to the first instance of incident DM. RESULTS: Among 128 752 participants, there were 19 439 incident cases of DM with median follow-up time of 20.7 years. The median KR was 0.36 and 12 participants (