Trans fatty acids from dairy foods show no increased cardiometabolic risk in systematic review and meta-analysis

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Nutrition research (New York, N.Y.) Published June 1, 2026 Medically reviewed June 1, 2026 Study authors: Gayet-Boyer Constance, Tenenhaus-Aziza Fanny, Torres-Gonzalez Moises, Givens D Ian, Schweitzer Cindy PubMed ↗ DOI ↗ By Dr. Amelia Tan, PhD · Internal Medicine & Chronic Disease

Key Takeaway

Consider that trans fatty acids from dairy foods may not increase cardiometabolic risk based on current evidence.

This is a systematic review and meta-analysis that synthesized evidence from 10 randomized controlled trials and 12 prospective cohort studies on trans fatty acids from dairy foods. The scope included biomarkers and clinical outcomes for cardiovascular diseases and type 2 diabetes, comparing TFA-enhanced dairy fat to regular dairy foods. The authors found no significant differences in total cholesterol, LDL cholesterol, HDL-C, lipid ratios, triacylglycerols, apolipoproteins, cardiovascular disease incidence, cardiovascular disease mortality, or type 2 diabetes risk. A slight decrease in HDL-C was noted for TFA-enriched vs. regular dairy foods, with an effect size of -0.05 mmol/L and a confidence interval of -0.10 to -0.00. Consumption of TFA (1.3-13.2 g/d) from different dairy types was not linked to adverse effects on cardiometabolic health. Limitations were not reported by the authors. The practice relevance is that dairy-derived trans fats may not pose additional cardiometabolic risk, but the evidence is not definitive.

Study Details

Study typeMeta analysis

EvidenceLevel 1

PublishedJun 2026

PMID42034918

View Original Abstract ↓

Dairy foods are becoming one of the major dietary sources of trans fatty acids (TFA) as global initiatives to eliminate industrially produced TFA are implemented. This systematic review aimed to assess the cardiometabolic effects of TFA from dairy foods, using data from randomized controlled trials (RCTs) and prospective cohort studies (PCS). We hypothesized that TFA from dairy foods would have no effect on biomarkers for or risk of cardiovascular diseases. Searches for RCTs and PCS were conducted in PubMed and EMBASE using PRISMA guidelines. RCTs compared the impact on blood lipids of regular dairy foods with TFA-enhanced dairy fat/foods produced by altering the cow's diet. Pooled meta-analysis of RCTs using the random effects model was performed for total cholesterol, low-density lipoprotein cholesterol, high-density lipoprotein cholesterol (HDL-C), total cholesterol/HDL-C, low-density lipoprotein cholesterol/HDL-C, triacylglycerols, apolipoprotein A1, and apolipoprotein B as continuous variables. Selected PCS analyzed associations between blood concentrations of trans vaccenic acid or trans palmitoleic acid and risk of cardiovascular diseases or type 2 diabetes. Among 10 RCTs, there were no significant differences in mean difference for any lipid biomarkers except for a slight decrease in HDL-C (mean difference: -0.05 mmol/L; confidence interval: -0.10 to -0.00) for TFA-enriched vs. regular dairy foods. Among 12 PCS, circulating concentrations of trans vaccenic acid or trans palmitoleic acid were not associated with increased risk of cardiovascular diseases incidence, mortality, or type 2 diabetes. Consumption of TFA (1.3-13.2 g/d) from different types of dairy foods was not linked to adverse effects on cardiometabolic health.