If you've struggled with your weight, you're not alone. But you are unique. Your individual DNA and genes both make you who you are and drive how your body responds to weight-loss attempts.
Somewhere between 25 and 70 percent of factors that affect body weight are tied to our genes. That's a broad range. And it means that the science is still evolving. But we do know that your DNA can make a difference in how full you feel as you eat, your appetite levels and how your body burns calories.
Scientists are learning more every day about how genes affect weight loss. As they learn more, we get closer to gene-based weight plans that fit your body's needs and boost the chances that you'll lose weight and keep it off.
Two common obesity-related gene variants are of the FTO, or "fat mass and obesity-associated" gene, and the appetite-regulating MC4R, or melanocortin-4 receptor. People who have either of these have a higher risk of obesity than those who don't. Yet they only account for a sliver of gene-related obesity. Variations in many other genes also affect risk. And there's much more to learn about factors such as:
More research is needed to fully understand whether and how different genes interact with these factors and affect our weight-loss attempts. For example, early research suggested that a person with a variant of the IRS1 gene might be more successful at weight loss when following a low-fat and high-carbohydrate diet versus a high-fat and low-carbohydrate diet. However, more recent research has shown no difference.
Many people who carry risky gene profiles aren't overweight and vice versa. That means that no matter your gene profile, your environment and your lifestyle still make a major difference in your weight.
Take the impact of fitness, for example: Active adults who have a common obesity-linked gene profile have a 30 percent lower risk of being obese than those with the same gene profile who aren't active.
Or, think about environment: In a large study of adults with an obesity-linked gene profile, those who were older were less likely to be obese. The younger participants were more likely to be obese. This suggests a strong influence of environment. The younger group grew up in a more obesity-promoting world with larger food portions, more sugary beverages and less physical activity.
While we don't yet have highly precise gene-based weight-loss plans, take heart that those plans will likely include actions we already know work well. These include exercising regularly and watching your calories. Fill your daily diet with plenty of fruits, vegetables and whole grains that not only help with weight but lower your risk of many diseases. Give your unique self your best chance and a healthy way of being.
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