Dairy consumption and subclinical atherosclerosis: A cross-sectional study among middle-aged Mexican women

Many dietary guidelines encourage low-fat dairy products; however, recent studies have found null and inverse associations between high-fat dairy intake and cardiovascular disease (CVD) risk. We examined the association between the intake of total dairy and different types of dairy and carotid intima-media thickness (IMT), a marker of subclinical atherosclerosis, in Mexican women.

Dairy consumption was assessed using a validated food-frequency questionnaire (FFQ) in 1759 women in the Mexican Teachers' Cohort (MTC) study who were free of CVD or cancer. We categorized participants according to total dairy intake and consumption of four mutually exclusive dairy groups: high-fat, low-fat, yogurt, and dairy with added sugars. IMT and atherosclerotic plaque were measured by B-mode ultrasonography. Subclinical atherosclerosis was defined as an IMT ≥0.8 mm and/or the presence of plaque. Multivariable linear regression and logistic regression models were used to respectively assess the mean percentage difference of mean IMT and odds ratios (OR) for subclinical atherosclerosis across quantiles of dairy consumption. Mean (±SD) age was 45.4 ± 5.0 years and the median (interquartile range: IQR) total dairy consumption was 11.0 (6.6, 17.1) servings/week. After adjusting for lifestyle, clinical, and dietary factors, comparing the highest category of consumption, to the lowest, total dairy was associated with increased IMT (2.6%, 95% confidence interval (CI): 0.6, 4.3; p-trend<0.01). Moreover, yogurt consumption was associated with lower odds of subclinical atherosclerosis (OR = 0.65, 95% CI: 0.47, 0.91; p-trend = 0.01).

While total dairy consumption was associated with carotid wall thickening, yogurt consumption was related to lower subclinical atherosclerosis.