Final answer:
Normal-weight and overweight individuals who engaged in self-imposed calorie restriction for 1 to 12 years displayed slower aging.
Step-by-step explanation:
According to research, normal-weight and overweight individuals who engaged in self-imposed calorie restriction for 1 to 12 years displayed slower aging than individuals eating a typical Western diet. Calorie restriction refers to eating a low-calorie diet while still maintaining proper nutrient intake. Several studies have shown that calorie restriction can increase lifespan and reduce the rate of age-related diseases in various organisms, although long-term studies in primates have shown mixed results.