What if we could stop obesity before it starts? A new international study offers hope for doing just that. Scientists have created a genetic test that can predict a person’s risk of developing obesity as early as early childhood.
This test, called a polygenic risk score (PGS), was made using genetic data from over five million people. The study was published in the journal Nature Medicine.
Obesity is becoming a serious global problem. The World Obesity Federation estimates that more than half of the world’s population will be overweight or obese by 2035.
Current treatments like diet changes, surgery, and medication don’t work for everyone and are not always easy to access. That’s why preventing obesity before it starts could be a game-changer.
The new PGS uses tiny differences in people’s DNA—called genetic variants—that affect things like appetite and how our bodies store fat. By adding up the effects of thousands of these variants, the score can tell how likely a child is to become obese later in life.
What makes this tool powerful is that it works before age five, long before other signs of obesity risk appear. This could allow doctors and families to act early with healthy habits to prevent weight gain.
The study was part of the Genetic Investigation of Anthropometric Traits (GIANT) Consortium, a large global project involving more than 600 scientists from over 500 institutions. It also included help from the genetics company 23andMe.
Together, they created the most accurate PGS for obesity to date. When tested on data from more than 500,000 people, the new score was twice as good at predicting obesity risk as the best previous test.
Professor Ruth Loos from the University of Copenhagen, one of the lead researchers, said that this is a major step toward using genetic tests in medical care. With better predictions, doctors could target support to kids who need it most.
But genetics is not destiny. The researchers found that people with a high genetic risk of obesity actually responded better to diet and exercise programs than others. However, they also tended to regain weight more quickly once the programs stopped. This shows that while genes can point to risk, lifestyle still plays a big role in what happens next.
There are still challenges. Even though the researchers used genetic data from many different backgrounds, the test still works better in people of European ancestry than in those of African ancestry. This highlights the need for more diverse research in the future to ensure the test is useful for everyone.
In short, this new genetic test could help spot obesity risk early and guide preventive care. While it doesn’t replace healthy habits, it offers a new way to support those most at risk.
If you care about weight loss, please read studies that hop extract could reduce belly fat in overweight people, and early time-restricted eating could help lose weight.
For more health information, please see recent studies about a simple path to weight loss, and results showing a non-invasive treatment for obesity and diabetes.
The study is published in Nature Medicine.
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