Oxidation of dietary linoleate occurs to a greater extent than dietary palmitate in vivo in humans

SummaryBackground It has been suggested that dietary polyunsaturated fatty acids (PUFA) are partitioned into oxidation pathways to a greater extent than saturated (SFA). Whilst this demonstrated in animal models, evidence humans is lacking. The potential divergence the metabolic fate of these (FA) may explain some reported differences ectopic fat deposition with SFA and PUFA enriched diets. Aims To compare whole-body palmitate linoleate after consumption single test meal. Methods In randomized, crossover design 24 healthy volunteers (12 males 12 females, matched for age BMI) underwent two study days separated by 2-week washout period. During each day participants consumed standardized meal which contained [U13C]palmitate or [U13C]linoleate. Blood breath samples were collected over 6 h postprandial period 13C enrichment CO2 plasma lipid fractions was determined. Results Appearance expired significantly (p < 0.05) increased containing [U13C]linoleate compared [U13C]palmitate. recovery tracer 8.9 ± 1.2% vs. 5.6 0.4% 0.05). incorporation from triacylglycerol non-esterified [U13C]linoleate, whereas phospholipids. Although 13CO2 higher females [U13C]palmitate, there no difference between sexes Conclusions We demonstrate comparatively following mixed-test found indications sexual dimorphism but not linoleate. Study registration http://www.clinicaltrials.org/ ID number NCT03587753.