Which of the following factors does NOT affect body fat accumulation?

The relationship between macronutrient meal content and body fat accumulation is not as direct as the other factors listed. While different macronutrients (proteins, fats, and carbohydrates) can influence metabolism and how the body utilizes calories, they do not directly determine the accumulation of body fat when caloric balance is considered.

Genetics plays a significant role in determining an individual's predisposition to store fat, affecting where they store fat and how their body metabolizes different nutrients. Caloric intake is fundamental; if a person consumes more calories than they expend, they will gain weight, which often includes fat accumulation. Caloric expenditure is equally crucial because it refers to the energy burned through various activities, and a deficit in caloric intake versus expenditure will typically result in fat loss.

In summary, although macronutrient content can influence aspects of metabolism and health, it is the balance of caloric intake and expenditure, alongside genetic factors, that are more definitive in assessing body fat accumulation.