Consumption of a diet high in dairy leads to higher 15:0 in cholesteryl esters of healthy people when compared to diets high in meat and grain

Abstract

Background and aimsA higher dairy product intake has been associated to higher blood concentrations of 15:0 (pentadecanoic acid), 17:0 (margaric acid), and 14:0 (myristic acid). This study investigates whether a diet high in dairy products influences cholesteryl ester fatty acid concentrations of these specific fatty acids (FA). Methods and resultsIn a randomized multiple cross-over study, 13 men and 17 women aged 22 ± 4 years with a BMI of 21.6 ± 2.2 kg/m2 received 3 isocaloric intervention diets (dairy, meat or grain) in random order. For this post-hoc analysis, FA in plasma cholesteryl esters were measured using gas chromatography. We performed a linear mixed model per centered log-ratio transformed FA, adjusting for period, and the interaction between diet and period. Consumed total fat intake per controlled intervention diet was 31.0 ± 0.9 en%/day (dairy), 31.5 ± 0.6 en%/day (meat), and 28.4 ± 1.2 en%/day (grain), respectively. The dairy diet led to higher relative concentrations of 15:0 when compared to diets high in meat and grain, (β; 0.27, 95%CI: 0.18,0.37; p = 1.2 × 10−5, and β: 0.15; 95%CI: 0.06,0.24; p = 1.2 × 10−2, respectively). The dairy diet also led to higher 14:0 when compared to the meat diet (β: 0.34; 95%CI: 0.21,0.46; p = 6.0 × 10−5), but not when compared to the grain diet. 17:0 did not differ between diets. ConclusionThe plasma cholesteryl ester fraction after a diet high in dairy was characterized by higher 15:0 levels. Concentrations of 14:0 were only higher when comparing the FA profile after a diet high in dairy when compared to a diet high in meat. Clinical trial registrationClinicalTrials.gov, NCT01314040.