Serum fatty acid composition in Spanish vegetarians

Abstract

[Introduction]: Plant food-based diets have become progressively common in developed countries, including Spain. However, information on the nutritional status of vegetarians according to biochemical determinations is lacking. [Objectives]: The aim of this study was to characterise the fatty acid profile of a Spanish vegetarian population. [Methods]: The design was a cross-sectional observational pilot study. Healthy adult vegetarians were recruited in the Madrid region (n=104, 83 women, 21 men). According to the type of diet, 49 were ovo-lacto vegetarians (11 men and 38 women) and 55 vegans (12 men and 43 women). Food intake and the use of supplements were assessed by a food frequency questionnaire and blood samples were collected and stored. Serum fatty acids were analysed by gas chromatography. [Results]: Fatty acid profiles did not vary significantly between vegetarians and vegans, or in relation to gender. Percentages of fatty acids of the whole studied population were 27.5% saturated (SFA), 24.6% monounsaturated (MUFA), and 47.9% polyunsaturated (PUFA) of which 45.2% were omega-6 (n-6) and 2.7% omega-3 (n-3). The main serum fatty acids were linoleic acid (34.4 ± 4.4%), oleic acid (23.4 ± 5.6%), palmitic acid (19.2 ± 2.3%), and arachidonic acid (8.3 ± 1.8%). A high PUFA n-6/n-3 ratio (19:1) was found in this population. Consumers of n-3 supplements (n=9, 10% of the population) compared to non-consumers presented a significantly lower serum n-6/n-3 ratio, 14:1 compared to 19:1 (p=0.025), due to significantly higher serum n-3 levels (3.7% compared to 2.6%, p=0.003) and a tendency to lower n-6 levels (42.6 % compared to 45.5%). [Conclusions]: Vegetarians whose diets are n-3-supplemented presented a more adequate serum lipid profile with higher PUFA n-3 levels and n-6/n-3 ratio.