Medically reviewed in October 2021
It's easy to argue that lifestyle choices and lack of willpower are responsible for weight problems (it's the argument that lean people tend to make).
But it doesn't explain the 95% failure rate (after 2 years) of people who have lost 50 pounds or more; they had plenty of willpower to lose the weight, but regained it nonetheless.
Researchers argue that obesity is more genetically linked than any other trait except height—and at least 50% of obesity cases clearly have genetic components.
Two Layers
The truth is, the waist-control game requires two layers—environment and genetics. Even if your genes have partly predestined you to a life of taking up two seats, that doesn't mean you should abdicate control of your body. When you make the right behavioral and biological changes, you'll be able to stay healthy and avoid the bad side effects of excess weight, like diabetes, high blood pressure (hypertension), and arterial inflammation.
About 10% of the obese population has genetic challenges that may make a supermodel contract impossible. But the bigger risk with these genes is not the weight itself—it's the predispositions for risks associated with obesity. For example, one genetic problem associated with being overweight is called leptin deficiency. (Leptin is a hormone associated with satiety. Learn more about leptin here.) Folks who either don't produce leptin or who block its signals usually become morbidly obese, and the problem is surely genetic.
Depends on Weight
Again, however, although some people have these abnormalities, they tend to be the minority of the population. If you need to worry about losing only 25, 35, or even 50 pounds, your problem is not likely to be genetic. But if your excess weight exceeds 100 pounds, most doctors would consider testing for genetic abnormalities.
The example of leptin is only the tip of the scientific iceberg, as far as genetics and obesity are concerned. As the fight against obesity continues, we'll probably find more and more biochemical problems that may be contributing to your weight problem.
That said, the onus of waist management still falls on you. Improve your environment and your behaviors so that your genetics can work for you, not against you.