Associations of common fats and oils with cardiometabolic health outcomes in the Framingham Offspring cohort.

Background/objectives: Evidence on the long-term associations between common fats and oils and cardiometabolic health is lacking. We evaluated the associations of butter, margarine, and non-hydrogenated oils with cardiometabolic risk (CMR) and the development of cardiovascular disease (CVD) and type 2 diabetes (T2DM) in the Framingham Offspring cohort.

Methods/subjects: We included 2459 subjects (≥30 years) with valid three-day food records. Multivariable Cox proportional hazards models were used to compute hazard ratios for incident CVD and T2DM over ~18 years; analysis of covariance was used to estimate adjusted mean levels of CMR factors (adiposity, insulin resistance, fasting glucose, lipids) over four years associated with baseline intakes of butter, margarine, and non-hydrogenated oils.

Results: Higher intakes of butter (>5 vs. 0 g/day) were associated with less insulin resistance (p = 0.0011), higher HDL-C levels (p = 0.0021), lower triglycerides (TG) (p = 0.0032), and lower TG:HDL ratio (p = 0.0052), as well as a 31% lower risk of T2DM (95% CI: 0.49, 0.97). Higher margarine intakes (>7 vs. <2 g/day) were associated with a 29% increased risk of CVD (95% CI:1.02, 1.63) and a 41% increased risk of T2DM (95% CI:1.02, 1.95). Lastly, higher consumption of non-hydrogenated oils (>7 vs. ≤2 g/day) was associated with a 0.6 kg/m² higher BMI and 8 mg/dL higher LDL-C levels.

Conclusions: More than one teaspoon (5 g) of butter/day was beneficially associated with several CMR factors and a lower T2DM risk, while margarine was associated with an increased risk of both CVD and T2DM. These findings suggest butter may be a healthier dietary fat source for the benefit of CMR.