The Challenge of Long-Term Weight Loss: Is Your “Set Point” Holding You Back?
Every day, we learn more about efficient belly fat loss through research, and while many people believe in the positive effects of diets like keto and intermittent fasting, evidence suggests that, in the long run, people often regain the weight they initially lost.
When we try to lose weight, we are working against our body, which likes to hold on to fat reserves, as it anticipates tough times ahead. “Human preferences for high-energy, sweet, and fatty foods may have evolved for survival reasons,” as suggested by this 2010 article on Human Perception and Preferences for Fat-Rich Foods. Our body is content to store some fat because it knows that at some point, it may need to use it to keep us alive. So, in theory, more fat reserves equal a better chance of survival.
Both theories suggest that our body has a preferred weight that it likes to maintain, whether we like it or not. This would explain why we pile the weight back on as soon as we finish the last 4-week diet. The theory also implies that once we stop forcing our body to do something it really doesn’t like (i.e., getting rid of fat storage), it will revert to what it thinks will serve its survival best.
The bad news is that this system can not only be flawed but also abused by people. For example, our bodies can suffer from leptin resistance, with leptin being a hormone often referred to as the “hunger hormone.” A study called Leptin Resistance: Underlying Mechanisms and Diagnosis suggests that “decreased sensitivity of tissues to leptin leads to the development of obesity and metabolic disorders such as insulin resistance and dyslipidemia.”
Poor eating habits can also influence these theoretical points, especially calorie-restrictive diets. When we force our body to lose weight due to starvation, it tends to lower our energy expenditure in response. Once we return to our usual diet, the body will gladly replenish the lost fat and do so even more quickly, as it has already reduced its energy expenditure by lowering the resting basal metabolic rate (BMR), as explained in this research paper titled Reduced Metabolic Rate After Caloric Restriction – Can We Agree on How to Normalize the Data?
This could also explain why people gain more weight when they return to normal food consumption levels after low-calorie diets. Since the body has lowered its BMR, eating the same amount of food you used to eat will result in an even larger calorie surplus and, therefore, a quicker replenishment of the fat reserve.
An article called Does Metabolism Matter in Weight Loss? published by Harvard Medical School mentions that “our body is also programmed to sense lack of food as famine.” In response, our BMR slows down, meaning fewer calories burned over time. That is one of the reasons why losing weight is often difficult.
The more frequent and longer you do extreme calorie-restrictive diets, the more likely you are to damage your metabolic system and sustain the “weight loss, put more weight back on cycle.”
It may be challenging for some but not for others – leptin resistance may come into play in some cases – but in non-extreme cases, it is more than possible to lose some weight through a combination of moderate exercise and a balanced diet. Resistance training is also said to help keep the weight off, as noted in an appropriately titled article Resistance Training Preserves Fat-Free Mass and Resting Energy Expenditure Following Weight Loss.
One important thing to keep in mind is timing, as in letting your body adjust to the changes. Your body is extremely adaptable but also slightly pessimistic, so it may change rapidly in response to negative stimuli like food deprivation but responds more slowly to positive ones, as it anticipates food deprivation happening again in the future…
A gradual decrease in calorie intake and a moderate increase in physical exercise can help put the body on a more sustainable and healthy trajectory of long-term body weight.