Final answer:
The main factors contributing to upper body fat accumulation are overeating and a lack of physical activity, which lead to overweight and obesity, along with associated health risks.
Step-by-step explanation:
The main contributors to full upper body fat are overeating and inactivity. Humans are biologically wired to store excess calories as fat, a trait useful during times of food scarcity. However, with today's readily available high-calorie foods and a sedentary lifestyle, many individuals accumulate adipose tissue, leading to overweight or obesity. Obesity is linked to various health issues, such as diabetes, heart disease, and certain types of cancer. Genetics can influence where fat is deposited in the body and one's predisposition to obesity, but lifestyle changes in diet and exercise remain the most effective ways to manage body fat levels.
Learn more about Obesity