The Set Point Theory Explained
The concept of Intuitive Eating has lately stepped into the spotlight of attention, and for a good reason! Influencers have been very vocal about it, so there is a great chance you have seen the term “set point theory” in some of their posts. You may have been wondering, what is this theory, and how is it connected to Intuitive Eating, anyway?
In this article, we unpack the basics of Set Point Theory. We also take it a bit further in an effort to grasp the multiple factors that lead to an individual’s weight and the mechanisms that regulate it.
The Energy Balance
Our bodies are energetic systems. They take us through our everyday lives using energy supplied by none other than the food we consume. To better understand the concept of energy coming in and out of our bodies, imagine a scale on which there is energy input on one side and energy output on the other.
NOTE: The word “calorie” will be used in this article. It only serves as an energy measurement unit.
The Input
Food, our body’s essential power source, is grossly broken down into 3 macronutrient categories: protein, fat, and carbohydrates (+ alcohol, but that is for another post). Most products contain all 3 macronutrients in different proportions. Each one has a specific calorie content, which cumulatively leads to the energy we take from a certain food.
2. The Output (TEE: Total Energy Expenditure)
BMR (Basic Metabolic Rate) – 60/70% of TEE
The amount of energy our body needs to preserve itself in life. Meaning, doing nothing but its basic functions (breathing, heartbeat, etc.) while in a state of total rest.
TEF (Thermic Effect of Food) – 10% of TEE
The energy our body uses to digest, absorb, and store the food we eat (that takes some effort, too!).
Physical Activity – 20/40% of TEE
The energy expenditure of PA depends on its intensity, duration, and the idiosyncratic response of each person to exercise.
NEAT (Non-Exercise Activity Thermogenesis)
According to this paper, NEAT is the energy expended for everything we do that is not sleeping, eating or sports-like exercise. The energy we spend to perform our daily activities, like brushing our teeth or fidgeting.
Diet culture is based on the simplistic idea that if we tip the scale towards the output, our bodies will resolve to use the stored energy, mostly (but not only) in fat reserves, resulting in weight loss.
This equation is unmistakably correct… if you are a computer program! For many years, dieticians and others have perpetuated this belief, even when there is scientific evidence, as old as 60 years, that points out the flaws of this theory.
The Yo-Yo Effect
If you are or have ever been on a diet, you know all too well that maintaining the reduced weight is even harder than achieving it. According to this meta-analysis, individuals maintained only 67% of their initial weight loss at 1 year post-diet, which became 21% at 5 years. This data proves that you are not the only one since weight regain is the norm!
Why does the yo-yo effect happen?
This comprehensive report suggests that our body weight is affected by environmental and behavioral pressures with their distinct genetic background. The fragile balance of this system is maintained by the homeostatic mechanisms of our body. These great powers cooperate to keep our body in a “steady state” weight or a set point weight, as we call it.
When we voluntarily change our environment by dieting and our behavior by exercising, the biological factor of the trio will work its hardest to bring the system back to the previous balance. When the new environmental and behavioral pressures that pull the system downward stop (a.k.a. you stop dieting and exercising), the only power pulling the system is upward. Imagine it like an elastic band. You keep pulling it to go down, but the elastic will jump to its original length when you stop applying that force.
The Set Point Theory
What is the set point theory?
The above concept is better explained with the help of the Set Point Theory. Research suggests that there is a certain set point weight (or adiposity level) that each individual “feels comfortable in”. This is the weight we easily maintain without effort while living our usual lives. This set point is encoded in our brains and protected by our metabolic mechanisms.
According to this theory, our brain, where the “file” for the set point is stored, constantly communicates with the body. It receives messages for energy stores (adipose tissue) and nutrient availability (how much/what we consume). When there is an imbalance that will compromise the set point weight, the brain functions as a thermostat that regulates the metabolism (our body’s biochemical procedures) accordingly.
What changes in our body when we diet?
In short, when we cut down our calories, our metabolism also drops to prevent weight loss. Similarly, when we overfeed, our metabolism shoots up.
When we diet, our brain detects food scarcity and resolves to spend less energy to prevent starvation. Consequently, all the 4 categories of energy output we mentioned above are affected. Our body mass is less, so our preservation needs (BMR) are also less. Our energy tends to be lower, so we usually exercise or move less (Physical Activity and NEAT). On the contrary, neuroendocrine changes happen and result in greater absorption and storage of food (TEE).
In greater detail, our satiety hormones, leptin, and insulin decline while our hunger hormone ghrelin goes up. Meanwhile, the sympathetic system and thyroid hormones (the systems that keep us up and running) appear reduced. There is also a shortening of the times of gastric emptying, which also increases hunger.
Set Point Theory Criticisms
The Set Point Theory has been met with some resistance. It has been said that it doesn’t explain the outburst of “obesity” in recent times. This could be because our thermostat seems to be asymmetrical. In other words, it is activated “more” in restriction than overfeeding. This is likely a survival mechanism to keep our bodies from starvation.
Another criticism relates to the fact that the Set Point Theory does not take into account the multidimensional factors that affect an individual’s weight.
An understanding of the diverse factors that contribute to one’s weight
Genetics
According to this article, more than 30 genes have been found to relate to BMI. Our understanding of the genetic background of weight is small, but its primal contribution is commonly accepted.
Environment
In this category, we find factors like eating habits (and everything that has affected their formation) or our mental state. Just take a look at this “Obesity Map” by UK Government’s Foresight Programme for a better understanding of the complexity of the mechanisms that regulate weight.
The Gut
The gut microbiome has been characterised as the “second brain”. It comes in direct contact with and processes the food. As a response, it sends powerful messages that affect our hunger, satiety, and caloric intake to the brain.
Take-Home Message
Thank you for sticking with me to the end of this science-filled article. We have unpacked a lot of information and uncovered several diet-culture mistakes. However, we have only scratched the tip of the iceberg.
There are two things I would like you to take away from this article:
A lot of the beliefs perpetuated by diet culture are outdated or worse, false. Don’t take anyone’s words for granted.
Take a second look at the obesity map and understand that criticising “larger” bodies for “unhealthy” food choices and lack of physical exercise is misinformed.
If you’re struggling with emotional eating, compulsive eating, over eating issues or Binge Eating Disorder, you can book a call with me by clicking the button below - I can’t wait to meet you!
