High blood cholesterol levels increase the risk of atherosclerosis even in youth, especially when this indicator fluctuates. This emphasizes the need to maintain low cholesterol levels throughout life, said the authors of the publication in Nature. Atherosclerosis is the most important cause of heart and vascular disease. It increases the stiffness of blood vessels and leads to narrowing of their lumen due to plaques composed of fat, cholesterol, calcium and other substances circulating in the blood. Typically, in animal studies of atherosclerosis, adult mice are fed fatty foods for several weeks. In the new work, the scientists tested what would happen if the mice followed such a diet for a lifetime. The authors noted that their study was one of the first to examine this question. The high-fat diet increased the risk of atherosclerosis even in young mice. The situation was worst when high-fat and low-fat weeks were alternated. This explains why not regularly taking statins (cholesterol-lowering drugs) does not help reduce cardiovascular risk. Researchers recommended that people follow a healthy diet from a young age and not stop taking statins even when cholesterol levels normalize.