
What are the causes of obesity?
Obesity is a complex disease and there are many causes of obesity. Learn some of the reasons for obesity and how they affect how obesity is managed.
Losing weight and keeping it off is often seen as a question of “energy in and energy out” – how much you eat and how much you move. But science has proven that there are many causes of obesity, some of which are beyond your awareness or control.
Model portrayal. Not an actual patient
Obesity is a chronic disease. And just like many other chronic diseases, it develops over time from a combination of biological, psychological, and environmental factors.
But what is it that makes people gain weight? Why do some people develop obesity? There isn't just one specific thing. As you can see in this video, obesity is far from simple.
The causes of obesity are complicated and vary from person to person. These include:
There are so many reasons for obesity. And once a person has developed obesity, it's not easy to manage weight and keep it off. Because of this, it can be hard to find the right way to treat or manage obesity.
Although the causes of obesity are complex, there are people who think that obesity is only a matter of lifestyle. It's a common belief that if a person only ate the right food and exercised in the right way, they wouldn't gain weight or develop obesity.
On some level, it is true. Losing weight does depend on the balance between how much energy you have (from the type and amount of food you eat) and how much energy you use (by exercising or carrying out normal body functions like breathing). But, this dramatically simplifies obesity. It's also hurtful to people who are affected by obesity. Eating less and moving more isn't always enough to manage weight and prevent you from developing obesity.
For Vicki Mooney, a mother of three living in Spain, the reasons for obesity seemed out of her control. “I go to the gym, I eat very small portions, I do yoga. But I am still overweight. People will say to me ‘eat less, move more, and you will be fine’. But it's really not that simple”.
Anyone who's also tried to manage weight without much success knows it far too well. You can try to be consistent and do all the right things to manage obesity and still struggle. Losing weight is hard. Keeping the pounds off after you lose weight is even harder.
Thankfully, the science shows that obesity is a manageable disease with many causes. More and more healthcare professionals recognise that obesity is a disease. At the same time, they're working to remove the stigma associated with obesity to make sure that people living with obesity get the help they need. In this video, medical experts from around the world talk about the reasons for obesity and other misconceptions. Play the video to hear their discussions about:
By considering all of the causes of obesity and approaching obesity similar to other diseases, healthcare professionals can help you transition to a healthier lifestyle and prevent complications from obesity.
To manage obesity in the best way, the first step is to identify which causes play a role. Since the causes of obesity vary from person to person, the approach should too. Each person will need to manage obesity and address the roadblocks of losing weight in a different way. Talk to your doctor to figure out the possible causes of obesity and to create a weight management plan specifically for you and your needs.
Talk to your weight management provider about treatment options that could prevent the weight you lose from coming back.
ZA25OB00138, May 2025