Have you tried countless diets only to end up at the same place you started? Or maybe you’ve seemed to get stuck at the same weight each time. There is a common theory, known as set point theory, that says our bodies have a weight that is “preset” by our DNA. This theory states that our body weight may have a more limited range which will change over time. It also states that some of us will have a higher set point than others.

As of right now, set point theory is just that—a theory. What we do know is that many factors can impact your body weight, like genetics, environment, lifestyle, medications, and health conditions to name a few. The body also has a regulatory system that aims to keep your body at a particular weight. Because of these regulatory measures, the set point theory is based on the concept that these biological signals will try to keep your body weight at a particular set point. The set point theory suggests that weight may fluctuate temporarily, but it will ultimately settle at the normal set point. 

The way this regulation works is through communication in your body between your brain and your fat cells. Based on the signals that your brain receives from your fat cells, your metabolism adjusts. Some of the key hormones that are part of this regulatory system are leptin and insulin.1 

Leptin is produced by fat cells. And the more fat cells the body has, the more leptin that is produced. Leptin is then carried through the bloodstream to the brain, where it can send signals to the hypothalamus and tell the brain how much body fat the body has. When there are higher amounts of leptin, that means the body is holding higher amounts of fat. Therefore, energy needs will be less. On the other hand, lower leptin levels let the brain know there is less stored fat and more calories will need to be consumed.2

Insulin is produced in the pancreas and is known as the body’s storage hormone. Throughout the day, the body secretes insulin in small amounts and in larger amounts after a meal. When glucose is detected in the bloodstream, insulin takes the glucose into the cells to be used for energy or stored, depending on what the body needs.

A question that many people have is whether or not your set point can change. The answer is yes. 

Some researchers say that over time, the body’s feedback system stops working as efficiently, causing leptin and insulin resistance. In turn, this could cause weight gain. Other factors, such as environment, lifestyle, and habits, can contribute to weight gain over time, too. According to the set point theory, the normal body set point can continue to gradually adjust. 

Another offset of this theory is that your genetics predetermine a range of an upper and lower body weight limit. Known as a settling point, this theory takes into account the various foods you choose and the environmental and lifestyle factors that can impact weight. The thought is that these settling points can be shifted up or down depending on these factors at a particular time. 

In order to make adjustments to a weight set point, the idea would be to slowly approach weight changes. Since the belief of set point theory is that your brain and body struggle to go outside of that set point, making small and sustainable adjustments rather than extreme changes can help influence and maintain a new set point.

Overall, current evidence suggests that weight isn’t based on just one factor. Instead, someone’s weight is impacted by a wide array of complex factors, both biological and environmental.3 Here are a few important factors to consider if you are working toward changing your current weight set point:

• Focus on small, sustainable changes: When you make small changes, it can help the body to adjust to a new normal over time rather than fight against it. 
  
• Set realistic goals: Setting reasonable expectations can help you achieve your weight loss goals and, hopefully, help you avoid the feeling of failure if things don’t happen as fast as you had hoped. Create a weight loss plan that works for you and the lifestyle you want to uphold. 
  
• Have a support system: Whether you have a family member, friend, or a professional, To help achieve your goals, it can help to lean on your support system. Whether it’s made up of family members, friends, or professionals, it’s beneficial to have someone around who is willing to support you throughout your health journey.

References:

1. Müller, M. J., Geisler, C., Heymsfield, S. B., & Bosy-Westphal, A. (2018). Recent advances in understanding body weight homeostasis in humans. F1000Research, 7, F1000 Faculty Rev-1025. https://doi.org/10.12688/f1000research.14151.1 

2. Speakman, J. R., Levitsky, D. A., Allison, D. B., Bray, M. S., de Castro, J. M., Clegg, D. J., Clapham, J. C., Dulloo, A. G., Gruer, L., Haw, S., Hebebrand, J., Hetherington, M. M., Higgs, S., Jebb, S. A., Loos, R. J., Luckman, S., Luke, A., Mohammed-Ali, V., O'Rahilly, S., Pereira, M., … Westerterp-Plantenga, M. S. (2011). Set points, settling points and some alternative models: theoretical options to understand how genes and environments combine to regulate body adiposity. Disease models & mechanisms, 4(6), 733–745. https://doi.org/10.1242/dmm.008698 

   3. Jung, C. H., & Kim, M. S. (2013). Molecular mechanisms of central leptin resistance in obesity. Archives of pharmacal research, 36(2), 201–207. https://doi.org/10.1007/s12272-013-0020-y