Short-Term Carnitine Supplementation Does Not Augment LCPω3 Status of Vegans and Lacto-Ovo-Vegetarians

Abstract

Objective: Long-chain polyunsaturated omega-3 fatty acids (LCPω3) synthesis, notably that of docosahexaenoic acid (DHA), from the precursor alpha-linolenic acid (ALA) proceeds with difficulty. We investigated whether carnitine supplementation augments the LCPω3 status of apparently healthy vegans and lacto-ovo-vegetarians, who are expected to have low carnitine status.Methods: Group A (n = 11) took 990 mg/day l-carnitine from weeks 1–4, and 990 mg/day l-carnitine + 4 mL/day linseed oil from weeks 5–8. Group B (n = 9) took 4 mL/day linseed oil from weeks 1–4, and 4 mL/day linseed oil + 990 mg/day l-carnitine from weeks 5–8. Fatty acid compositions of red blood cells, platelets, plasma cholesterol esters and plasma triglycerides were measured in the fasting state at baseline, and after 4 and 8 weeks.Results: Carnitine supplementation increased plasma free and total carnitine concentrations with 30 and 25%, respectively, but did not affect eicosapentaenoic acid (EPA) and DHA contents of any of the investigated compartments. EPA and DHA changes were negatively related to initial carnitine status.Conclusions: Our results suggest that carnitine is not an important limiting factor, if any, for LCPω3 synthesis in vegans and lacto-ovo-vegetarians. This conclusion is also likely to apply to omnivores. The most efficient means to augment EPA and particularly DHA status remains consumption of LCPω3 from e.g. fish or supplements.