To work right, your body needs the energy that comes from food. When you eat the same amount of food your body needs, your weight stays the same. If you get more energy from your food than you need, some is left over. Your body stores that extra energy as fatty tissue. If your body never uses the extra fat, you will gain weight. How much food you need depends on how fast your body uses energy. Some people with higher metabolism use energy faster than others. Some need more power because they are more active.
If others in your family are obese, then you have a higher risk for obesity. A study in Canada looked at 12 sets of identical twins. Each twin consumed 1000 extra calories a day for three weeks. All of the subjects in the study gained weight. But not all subjects gained the same amount of weight. The interesting thing, though, was that in each set of twins, one twin gained the same amount as the other.
Related: Surgical Treatment of Obesity
In 1994, scientists found a gene in mice that was linked to obesity. This gene produces the protein leptin, which contributes to feeling full. Mice with a defective gene eat large amounts of food. But when humans were studied, the results were not the same, So it seems unlikely that a single gene can explain severe obesity.
Genetic research does show that some processes don’t work as well in obese people as they do in others. These include how fat is burned, metabolism, and feelings of hunger and fullness.
Metabolism refers to how your body gets energy from food. Lots of things can affect metabolism. For instance, trouble with your thyroid gland can change your metabolism and lead to obesity or morbid obesity.
Eating and social habits
Your diet can affect your weight. Things like not eating a balanced diet or eating fast-food, and fatty snacks between meals can all cause obesity. Another habit that can cause obesity is eating portions that are too large or too rich. Drinking too many high-calorie beverages can also cause it. Not getting enough exercise can make the effect of these habits worse.
Most people’s eating habits are affected by their surroundings. For some people, smell and color will cause them to eat more. Some will eat to be social.