Associations between milk fat content and obesity, 1999 to 2016

Background: The relationship between milk fat content and body mass index (BMI) remains unclear. The objective of this study was to determine if milk fat content is associated with obesity in children, adolescents and young adults. Methods: We used repeated cross sections of National Health and Nutrition Examination Survey (NHANES), 1999 to 2016. Using logistic regression, we measured associations between first milk consumed after formula/breast milk (whole, 2%, 1%, or fat-free) and weight status (≥85th to <95th BMI percentile, overweight; ≥95th BMI percentile, obesity) among children 2 to 6 years (n = 8367). We also assessed associations between current milk type and weight status among those 2 to 20 years of age (n = 26 750). Results: Children 2 to 6 years with obesity were less likely to have been weaned to whole milk versus healthy weight children (adjusted odds ratio [aOR], 0.77; 95% CI, 0.60-0.98; P =.031). Individuals 2 to 20 years with overweight or obesity were less likely to drink whole milk as their current milk and more likely to drink fat-free or 1% milk compared with healthy weight children. Conclusions: Whole milk consumers are less likely to have obesity. It is unclear whether this relationship is causal or a reflection of United States Department of Agriculture recommendations. Further examination of the factors that influence milk choice among diverse cohorts would lend clarity to this important issue.