Influence of dietary habits, age and gender on plasma fatty acids levels in a population of healthy Tunisian subjects

The fatty acids composition of circulating blood lipids is expected to be altered by many factors (ageing, dietary intake, lifestyle...). In addition to the ageing consequences on their lipid status, elderly subjects represent a population at risk of nutritional imbalance. The main objective of the present study was to investigate the associations between dietary habits and the plasma fatty acids patterns in a healthy Tunisian population with an emphasis on the gender and ageing differences for the ∆6-desaturase activity and the EFA proportions. Nutritional habits and plasma fatty acids compositions have been therefore evaluated in 200 healthy volunteers (104 women and 96 men) aged between 40 and 82 years old. The findings revealed that the ∆6-desaturase activity was reduced in elderly subjects (by 24% and 10% in women and men respectively). Moreover, DHA (C22:6n−3) and AA (C20:4n−6) were found to increase respectively in high fish and meat consumers. Plasma fatty acids composition could be sensitive to dietary habits according to particular food items and should then help for the establishment of optimal nutritional proportions.