Controllable factors—for example, a high-calorie diet, emotional responses to food (such as eating when anxious or bored), too large portion sizes, automatic eating, and a lack of exercise—play a crucial role in the development of obesity.
Yet research confirms that more is involved in losing weight and keeping it off than just a lack of willpower or a sedentary lifestyle.
Factors That Cannot Be Changed
Although these factors are beyond your control, their impact on your weight can be modified by changing your diet and increasing your level of physical activity.
Heredity
Studies show that 80% of children born to two obese parents will themselves become obese, compared with 14% of children born to normal-weight parents.
Research on identical twins shows similarly high rates of inheritance factor when it comes to weight.
However, studies comparing the weights of adoptees with the weights of their biological and adopted parents indicate that genetic factors are responsible for only about a third of the difference in weight.
Heredity seems to influence the number of fat cells in the body, how much and where fat is stored, and how much energy the body uses at rest (metabolism).
In addition, childhood obesity tends to translate into adult obesity.
About 80% of obese children become obese adults (although only about 20% of all obese adults were obese as children).
