People of a normal weight might have shorter lifespans than people who are slightly overweight. Researchers have speculated that lowered mortality rate in people who are slightly overweight might be because of improved early prevention and management of weight-related conditions such as hypertension, diabetes and heart disease. Thinner people might not show symptoms as early, or their lower weight could be a result of them already being sick. Although people who are moderately overweight might have lower mortality rates than people who are underweight, of normal weight or obese, but they are not any less likely to develop weight-related conditions. Being slightly overweight also might be beneficial to elderly people who have chronic diseases because they might have more stored muscle mass and nutritional reserves that can help them remain stronger than their peers who weigh less.
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