Many people feel frustrated when trying to lose weight. They eat less, move more, and initially see results, only for progress to stall or the weight to return. One reason for this is something known as the body's weight set point.
A helpful way to understand this concept is to think of a thermostat in your home.
If you set the thermostat to 22 degrees, the heating or cooling system will automatically adjust to keep the room close to that temperature. If the room cools down, the heater turns on. If it becomes too warm, the system shuts off or cools the room down.
Your body regulates weight in a very similar way.
The brain, particularly an area called the hypothalamus, monitors energy stores, hunger signals and hormone levels to maintain a certain weight range. When body weight drops below this set range, the body responds by increasing hunger, reducing metabolic rate and conserving energy. The system is essentially trying to restore what it perceives as the correct setting.
Where insulin resistance becomes important is that it can gradually turn the thermostat up.
Insulin is the hormone responsible for helping move glucose from the bloodstream into cells to be used as energy. When the body becomes insulin resistant, cells stop responding effectively to insulin. In response, the pancreas produces more insulin to compensate.
Chronically elevated insulin levels have several effects that promote weight gain.
Firstly, insulin is a powerful fat storage hormone. High insulin signals the body to store energy rather than burn it. Secondly, it can disrupt appetite regulation, increasing hunger and reducing feelings of fullness.
Over time, this hormonal environment can shift the body's defended weight upward, like adjusting the thermostat from 22 to 26 degrees. Once that new setting is established, the body works hard to maintain it.
This is why many people experience strong hunger and metabolic slowdown when they attempt traditional calorie restriction. The body interprets the weight loss as a threat and activates mechanisms to restore the higher set point.
Importantly, this is not about willpower. It is physiology.
The encouraging news is that the thermostat can be gradually reset. Improving insulin sensitivity helps lower insulin levels and allows the body to access stored fat more effectively.
Strategies such as reducing refined carbohydrates and sugars, prioritising protein and whole foods, building muscle through resistance training, improving sleep and managing stress can all improve insulin sensitivity.
Over time, as the metabolic environment improves, the body's weight regulation system can shift toward a healthier set point, making fat loss and long-term weight maintenance far more achievable.
