Silicon is recognised as a protective trace element in atherosclerosis by epidemiologic and biochemical studies. The goal of the present work was the evaluation of the antiatheromatous effect of the natrium silicate in an experimental trial on 30 rabbits given a standard diet (control), an atherogenic diet (L1 lot) and a natrium silicate-supplemented atherogenic diet (L2 lot), by comparing the variation of the lipid pictures between each of the experimental lots and control. Levels of total lipids, cholesterol, triglycerides (TG), free fatty acids (FFA) and phospholipids indicated that the natrium silicate supplemented to the atherogenic diet minimised the lipid metabolism unbalance by keeping constant the level of FFA and TG in rabbits.