Long-term calorie restriction is highly effective in reducing the risk for atherosclerosis in humans

TLDR

Long‑term effects of caloric restriction on atherosclerosis risk are poorly understood. The study assessed how caloric restriction influences atherosclerosis risk factors in longevity‑seeking individuals. Eighteen long‑term CR participants and eighteen matched controls were compared on serum lipids, glucose, insulin, blood pressure, inflammatory markers, body composition, and carotid intima‑media thickness. Long‑term CR produced a leaner body, markedly lower lipids, glucose, insulin, blood pressure, inflammatory markers, and a 40 % reduction in carotid intima‑media thickness, indicating a powerful protective effect against atherosclerosis.

Abstract

Little is known regarding the long-term effects of caloric restriction (CR) on the risk for atherosclerosis. We evaluated the effect of CR on risk factors for atherosclerosis in individuals who are restricting food intake to slow aging. We studied 18 individuals who had been on CR for an average of 6 years and 18 age-matched healthy individuals on typical American diets. We measured serum lipids and lipoproteins, fasting plasma glucose and insulin, blood pressure (BP), high-sensitivity C-reactive protein (CRP), platelet-derived growth factor AB (PDGF-AB), body composition, and carotid artery intima-media thickness (IMT). The CR group were leaner than the comparison group (body mass index, 19.6 ± 1.9 vs. 25.9 ± 3.2 kg/m 2 ; percent body fat, 8.7 ± 7% vs. 24 ± 8%). Serum total cholesterol (Tchol), low-density lipoprotein cholesterol, ratio of Tchol to high-density lipoprotein cholesterol (HDL-C), triglycerides, fasting glucose, fasting insulin, CRP, PDFG-AB, and systolic and diastolic BP were all markedly lower, whereas HDL-C was higher, in the CR than in the American diet group. Medical records indicated that the CR group had serum lipid-lipoprotein and BP levels in the usual range for individuals on typical American diets, and similar to those of the comparison group, before they began CR. Carotid artery IMT was ≈40% less in the CR group than in the comparison group. Based on a range of risk factors, it appears that long-term CR has a powerful protective effect against atherosclerosis. This interpretation is supported by the finding of a low carotid artery IMT.