The aspects of biochemical transformation of natural lipids of vegetable, fish, and animal origin are considered on the model of biotechnical aspects of triglyceride transformation into products of various purpose. The indicators of biological efficacy of fats are presented regarding the systematization by groups of polyunsaturated, monounsaturated and saturated fatty acids. Some features of simulation of natural processes of hydrolytic fat degradation into energy-intensive products are discussed. At the same time, aspects of fat intake and their biochemical transformation in food systems by human enzymes, and biochemical transformation of lipids in vitro in the presence of commercial enzyme preparations were studied. The aspects of free fatty acid transformation into esters are considered for justifying their use.