In spite of documented hypocholesterolemic activity of polyunsaturated fatty acids the high amount of n-6 acids and low amount of n-3 acids in food can be a reason of coronary heart disease (CHD). Thus the safe food with very low n-6 to n-3 ratio is recommended. On the other hand polyunsaturated fatty acid reduce the body fat retention as they inhibit the synthesis of fatty acids in liver, increase fatty acids oxidation and induce the thermogenesis. Similar activity show the medium-chain fatty acids (C₆-C₁₂). When compared with longer chain fatty acids they are readily absorbed, they limit fat deposition and display antibacterial activity. An independent risk factor for CHD is also serum trigliceride concentration and the increased risk starts at their relatively low concentration.