Short-term diets enriched in stearic or palmitic acids do not alter plasma lipids, platelet aggregation or platelet activation status

Objective To determine whether healthy males who consumed increased amounts of dietary stearic acid compared with increased dietary palmitic acid through the consumption of commercially available foods, exhibited any changes in plasma lipids, platelet aggregation or platelet activation status.Design A randomised cross-over dietary intervention.Subjects and interventions Nine free-living healthy males consumed two experimental diets (stearic acid enriched, diet S, and palmitic acid enriched, diet P) for 3 weeks in a randomised cross-over design separated by a 3 week washout phase. The diets consisted of approximately 30% of energy as fat (30% of which was derived from the treatment diets) providing approximately 13 g/day as stearic acid and 17 g/day as palmitic acid on diet S and approximately 7 g/day as stearic acid and 22 g/day as palmitic acid on diet P. The dietary ratio of stearic to palmitic acids was 0.76 on diet S compared with 0.31 on diet P. Blood samples were collected on days 0 and 21 of each dietary period.Results LDL cholesterol levels and platelet aggregation response to the agonist ADP were significantly decreased (PConclusions Use of commonly available foods led to a 27% increase in stearic acid (diet S) and a 19% increase in palmitic acid (diet P), on diets S and P respectively, and no significant differences between the two diets in plasma lipoprotein concentrations, platelet aggregation or platelet activation status.