L-carnitine: food sources, adequate and clinically effective doses

Abstract

L-carnitine plays a key role in cell bioenergetics, it belongs to vitamin-like substances, but unlike vitamins, it not only comes from food, but is also synthesized in the body. Endogenous synthesis decreases with age, under certain physiological conditions, taking medications. In this regard, specialized food products (SFP) and food supplements are being developed, containing L-carnitine as one of the functional ingredients. Comparison of doses of L-carnitine approved for use in biologically active food supplements and specialized food products with doses that provide a clinical effect.A review of existing literature on this issue in recent years was carried out using the RSCI, Pubmed databases and in the Google Scholar, ResearchGate systems. The amount of L-carnitine contained in a daily portion of SPP is established by domestic regulatory documents based on an adequate level of daily intake for adults, which is 300 mg and the upper permissible level of daily intake in the composition of SFP and food supplements is 900 mg/day. Reception of L-carnitine 1–2 g per day. within 5–12 weeks led to an increase in its concentration in the blood plasma, and also improved the indicators of the antioxidant status. Long-term intake of L-carnitine in doses of 2–3 g in patients with dyslipidemia, type 2 diabetes (DM2) and cardiovascular diseased (CVD) led to an improvement in the lipid profile of blood plasma, glycemic control, and had an anti-inflammatory effect. The condition for achieving a clinical effect in patients is long-term use and high doses. The intake of physiological doses of L-carnitine is appropriate for individuals from risk groups. Clinically effective doses of L-carnitine, when used for at least 12 weeks, correspond to or are 2 times higher than the upper permissible intake level in the composition of SPP and dietary supplements.