Exploring the effects of Cheddar cheese intake on vitamin K status and lipid profiles in overweight middle-aged adults

Background: Cheese serves as a dietary source of vitamin K; however, its impact on vitamin K status biomarkers in humans and the role of dietary vitamin K in modulating lipid profiles have yet to be elucidated. Objective: To explore the effect of six weeks of daily consumption of pasture-derived and total mixed ration (TMR)-derived Cheddar cheese on vitamin K status biomarkers and lipid profiles. Design: Biobanked samples (n = 60), including pasture-derived (n = 33) and TMR-derived (n = 27) Cheddar cheese groups from a previous human intervention study, were analysed. The original study examined the effects of six weeks of daily intake of 120 g of Cheddar cheese on metabolic health biomarkers in adults over 50 years with BMI ≥ 25 kg m^-2. Vitamin K-dependent proteins, including dephosphorylated-uncarboxylated matrix Gla protein (dp-ucMGP), undercarboxylated osteocalcin (ucOC) and carboxylated osteocalcin (cOC), were measured using ELISA kits. The dp-ucMGP level and the ucOC : cOC ratio were used as vitamin K status biomarkers. Lipid profiles, including triglycerides, total cholesterol, HDL, LDL, and VLDL cholesterol, and apolipoprotein B, were measured by NMR spectroscopy. Results: Overall, Cheddar cheese intake (n = 60) led to decreases in dp-ucMGP (-34.73 pmol L^-1; 95% CI: -47.14, -22.33) and ucOC : cOC (-0.047; 95% CI: -0.07, -0.02) after 6 weeks of consumption, with no differences between the groups. There were no differences in the changes in anthropometric markers or lipid profiles between groups. The sex-by-treatment interaction showed a significant impact on total cholesterol (P < 0.001), HDL cholesterol (P < 0.001) and LDL cholesterol (P = 0.002) levels. Among males, the TMR-derived cheese group exhibited a significantly greater increase in HDL cholesterol (P < 0.05). Among females, TMR-derived cheese consumption was associated with significantly greater decreases in total, HDL and LDL cholesterol levels (P < 0.05) compared with the pasture-derived group. Conclusion: Cheddar cheese intake may improve vitamin K status, and vitamin K intake from cheese may induce sex-specific effects on blood lipid profiles in overweight middle-aged adults.