Final answer:
Genetics can account for about 40 to 70 percent of the predisposition to obesity, with children of obese parents having a significantly higher likelihood of becoming obese themselves. The obesity epidemic in the U.S. also involves high-calorie diets, sedentary lifestyles, and a shift from a plant-based to a fatty and processed food diet.
Step-by-step explanation:
Genetic Influences on Obesity
Genetics play a significant role in the development of obesity to various degrees. When considering how much genetics are responsible for obesity, research indicates that genetics might account for about 40 to 70 percent of the predisposition to obesity. This is due to multiple genes involved in controlling appetite and metabolism, which, when combined with sufficient food energy, can increase the risk of becoming obese. Moreover, familial studies have shown that children of obese parents have an approximately 80 percent chance of being obese themselves, compared to less than 10 percent when both parents are of normal weight.
Contributing Factors to Obesity in the United States
Obesity has reached epidemic proportions in the United States. Factors contributing to obesity-related diseases include high-calorie diets rich in carbohydrates and sugars, sedentary lifestyles prompted by changes in work and technology, and genetic predisposition. The shift in diet from the evolutionary norm, where earlier diets were predominantly plant-based and lower in fat, to modern diets, which are higher in fats and processed foods, has played a central role in the rise of obesity rates. Moreover, people who have central obesity, where excess fat is stored in the abdomen, are at an even greater health risk.