Based on the analysis of literature sources, components of food biologically active additives with preventive properties are established. With applying HyperChem (computational chemistry), we study the basic molecular features of lecithin, oleic acid and L-carnitine. Revealed that lecithin has a hydrophilic and hydrophobic properties, it is capable of forming stable emulsions and soluble on the surface section of phases. Molecule of L-carnitine has a low potential energy (48487.1 kcal / mol) and can participate in subsequent cycles of conversion of fatty acids. Formation of complexes between L-carnitine and oleic acid was investigated with the application of computational chemistry (molecular docking), the findings confirmed the possibility of formation of complex compounds, which testifies to the lipotropic effects of L-carnitine. The molecular interaction between human pancreatic lipase (receptor) and lecithin (ligand) analyzed. Based on the conducted researches, confirmed the possibility of blocking the active site of the lipase of pancreatic juice with two molecules of lecithin, this forms a stable compound with the energy of intermolecular bonds is equal to - 412.36 kkal. The expediency of using l-carnitine and lecithin for activators of the metabolism and lipolysis. Revealed that these drugs affect the absorption of fat in the intestine and prevent tumor fat. On the experimental samples (homogenized fat in water) and experimental animals used prophylactic properties of biologically active additives proven. After two hours of processing of lipid samples with pancreatic lipase and the addition of lecithin acid value of the mixture was equal to 11.91 compared with a control sample in which this indicator was equal to 77.87 mg KOH / g oil. Studies in experimental animals show, that lecithin and L-carnitine reduce obesity in experimental animals and normalize lipid, mineral, protein and carbohydrate metabolism, even in the body with increased weight
