What is Set Point Weight Theory?

Set point weight theory is a helpful concept for understanding weight science, the fluctuations you experience in weight, “healthy weight,” and why diets don’t work. This blog post explains what set point weight range is and answers commonly asked questions about it.

Thanks to more awareness around body diversity and the high failure rate of dieting, many people I talk to recognize the many problems with BMI. They know that their “healthy weight” according to the BMI scale isn’t actually healthy for them. Still, thanks to a medical culture that equates weight and health, they feel anxious that their current weight might not be healthy, and want to know how much they “should” weigh.

It’s a concern that makes a ton of sense! No one wants to deal with illness or chronic disease, and if you’re told maintaining a healthy weight will help reduce that risk, of course you would want to know what your weight should be.

Spoiler alert: it’s impossible to know at what weight someone is healthiest. Not only that, but even if there was a machine that was able to predict your healthiest weight, that doesn’t make dieting any more sustainable. And of course, your healthy weight could actually be higher. In this fatphobic culture we live in, would the knowledge that weight gain would improve your health actually make you want to gain weight? It’s a sad testament that for many people, the answer would be no.

When clients have questions about what their healthy weight is, we teach them about set point weight theory. While it has it’s limitations, it’s a helpful concept for better understanding weight science and the relationship between weight and health, and the natural fluctuations and changes that happen on the scale.

Set Point Weight Theory

Our body has many mechanisms for maintaining homeostasis - “a self-regulating process for maintaining internal stability while adjusting to changing external conditions.” Barring extreme circumstances or a health condition that disrupts these mechanisms, the human body will maintain a temperature between 97 and 99 degrees F, a blood pH level around 7.35-7.45, and keep serum electrolytes like potassium and sodium within a tightly controlled range.

Weight is another area the body tries to maintain homeostasis. Set point weight theory posits that humans naturally have a weight range that their body fluctuates within, a range that seems to be between 5-20 lbs for most people. This range is individual, with larger people fluctuating within a wider range, and thinner people fluctuating within a smaller range. Set point weight range seems to be about 5% of one’s weight, which is more pounds for someone who is a higher weight versus lower.

One’s set point weight range varies from person to person, with some people having a set point weight range that may be within the “overweight” or “ob*se” categories” (as defined with BMI, which btw is BS), and others having a set point range that aligns with what the BMI scale says their weight should be. People with a higher set point weigh range aren’t automatically unhealthy, nor are people with a lower set point weight range automatically healthier. Research shows that people with a BMI > 30 who engage in healthy habits, like eating enough fruits and veggies and not smoking, have the same health status as people in the “normal weight” BMI category who also engage in these behaviors. Different set point weight ranges are simply an example of body diversity! While some homeostatic mechanisms are consistent person to person, weight is not one of them. It’s not a perfect analogy, but you can think of it like skin color. People may get darker in the summer and lighter in the winter, but there is quite a bit of diversity in skin colors between humans.

Can I get outside my set point range?

Short answer: yes.

Let’s go back to the body temperature analogy. While your body tries to keep your temperature between 97 and 99 degrees F, there are things that can bring your body outside of that range. You could fall into an icy pond, catch the flu, go hiking up a snowy mountain without appropriate gear, or go running in a hot desert.

Similarly, there are things that can bring your body outside of it’s range. When someone is struggling with an eating disorder and loses weight as a result (p.s. not everyone loses weight as a result of restriction), this is an example of their body being outside their set point range. It’s one of the reasons why the primary treatment for anorexia, bulimia and ARFID is nutrition rehabilitation and weight restoration.

Weight can also go higher than ones set point range. Yes, excess caloric intake can cause one’s weight to go outside of it’s set point range, but there are also over 100 other factors that influence weight - medical conditions, stress, medications, physical activity, gut microbiota, and sleep patterns are a few that come to mind. When someone gains weight, food is often named as the culprit, but that’s not always the case. Even if someone is experiencing weight gain due to excessive caloric intake, there’s probably a good reason, and they deserve respectful support and care, not shame.

It’s important to remember that if a body is higher than it’s set point weight range, that doesn’t mean intentional weight loss is the solution. It means there are either behaviors, medical conditions, psychological conditions, or other factors that deserve to be addressed. The weight is a symptom of something else going on. Also, quick reminder that just because someone is at a higher weight, that doesn’t automatically mean they are outside their set point range!

While your body can go outside it’s set point weight range, it will work to keep it within it’s homeostatic range. Your body does this through changes to hunger and fullness cues, slowing or speeding up metabolism, increasing or decreasing the hedonic factor of food, hormonal shifts, and even by shifting gut bacteria to be more or less efficient at absorbing calories from food. You don’t have to work hard to keep your body in it’s set point weight range - your body tries to do that for you!

Can your set point weight range change?

Yes, as you get older, your set point weight range may shift up or down. Due to a combination of genetics and other factors, some people will lose weight (especially muscle mass) as they age, while others will gain weight (which actually seems to be protective for health).

One’s set point weight range can also shift up due to dieting and disordered eating. I know this is really hard to hear if you have a history of chronic dieting or an eating disorder, and wonder if that has caused your body to be at a higher weight. I often talk to clients who feel that they have “ruined” or “broken” their body. If that’s you, please give yourself some grace. Eating disorders are not a choice, and if you were dieting, you were simply doing what pretty much everyone in society tells people to do. It was not your fault.

That said, I want to offer a gentle reframe. Your body is not broken. If your body has gained weight as a result of dieting or disordered eating, reminder that it is because it was trying to protect you! It makes sense that if it has experienced the trauma of starvation, whether from dieting or an ED, your body would adapt to that. While you might not like the fact that your weight is higher, and that’s totally OK if you don’t, it is an example of your body working as it should and just trying to keep you alive.

How do I know if I’m in my set point weight range?

It’s understandable that someone would want to know what their set point weight range is, however there is no objective way to determine what it is. If you’re finding yourself really caught up in trying to figure it out, I think that’s a good sign to dig a bit deeper into your thoughts and feelings about weight and body size. It’s also a good sign to practice sitting with the discomfort of the unknown.

That said, generally speaking your weight will settle within it’s set point range when you’re eating enough food and generally taking decent care of yourself. Instead of focusing on what your weight “should” be and trying to get it there, I’d encourage you to focus on figuring out a way of taking care of your body that feels good, physically and mentally, and let your body settle where it needs to.

Struggling to let go of the scale and feed yourself in a way that feels good? We work with clients virtually throughout the US, and in our Columbia, SC office providing intuitive eating and recovery coaching and counseling. We are also in network with Blue Cross, Blue Shield insurance and your plan may cover services at no cost to you. Read more about our practice philosophy, and reach out for more information!