Cumulative soft drink consumption is associated with insulin resistance in Mexican adults.

BACKGROUND: Insulin resistance (IR) is an important risk factor for type 2 diabetes (T2D) and other cardiometabolic diseases. Recent studies suggest that soft drink consumption could increase IR. However, inconsistent findings have been observed. OBJECTIVE: The aim was to estimate the association between the cumulative consumption of soft drinks and IR by means of the HOMA-IR in Mexican adults. METHODS: We analyzed the association between cumulative consumption of soft drinks and HOMA-IR change after 7 y of follow-up in participants (n = 1073) of the Health Workers Cohort Study. Soft drink consumption was estimated by food-frequency questionnaires. Insulin was measured by chemiluminescence, and fasting glucose was measured with the enzymatic colorimetric method. HOMA-IR was computed as fasting insulin (mIU/L) × fasting glucose (mmol/L)/22.5. To assess the relation between cumulative soft drink consumption and HOMA-IR change, we performed robust linear regression models. Additionally, we used fixed-effects models to estimate the association between changes in soft drink consumption and change in HOMA-IR. RESULTS: At baseline, the average age was 44 y. Mean cumulative soft drink consumption was 0.42 servings/d. Median HOMA-IR increased from 1.5 at baseline to 2.0 at follow-up. Soft drink consumption was positively associated with HOMA-IR change. In the multiple linear regression analysis, for each increase in the consumption of 2 (355 mL) soft drinks/d, the average change between baseline and follow-up HOMA-IR showed an increase of 1.11 units (95% CI: 0.74, 1.48). CONCLUSIONS: Our data support the hypothesis that, in Mexican adults, a higher soft drink consumption is associated with an increase in HOMA-IR, despite known risk factors. These findings support the need for reinforcing policies to reduce soft drink consumption in our population.