Final answer:
To gain up to 5 years of healthy living, people following Calorie restriction must restrict their energy intake by at least 20%.
Step-by-step explanation:
To gain up to 5 years of healthy living, people following Calorie restriction must restrict their energy intake by at least 20%. Calorie restriction refers to eating a low-calorie diet while still maintaining proper nutrient intake. It has been shown that restricting caloric intake can reduce tumor growth and increase life span in animal studies.