Have you ever started a diet, lost a few kilos, and then suddenly nothing? You’re still eating the same food. You’re still counting every single calorie, but the scale will not budge. Even worse, you are feeling hungrier, more tired, and somehow the weights start creeping back on. This isn’t just about willpower, and it is not your fault. It’s your biology, and the system behind it is called the negative feedback, run by your brain. In this video, I will show you how your body fights to protect its fat storage and why understanding this hidden system is the first step to escaping the weight regain trap. I am Dr. Qutayba Almerie, a weight loss surgeon, helping you understand obesity and your health. If you are interested in the science behind weight and the real solution that goes beyond diet myths, hit the subscribe button so you don’t miss future videos.
How your body fights back
Let’s start with the one signal you have felt. Hunger. It’s not just an empty stomach. It’s one of the most powerful survival tools that your body has. And it is carefully controlled by your brain. Specifically, a small part of the brain that’s called the hypothalamus. Think of it as your body’s thermostat, but instead of regulating the heat, it regulates the fat storage. Now, how does it know how much fat your body has? This is where a hormone called leptin comes in. Leptin is a hormone that’s made by your fat cells. The more fat you carry, the more leptin you will produce. Let’s say a constant signal reporting back to the brain about how much fat it has. Here is what happens when you start losing fat. S, ay for instance by dieting. Leptin will drop, and the hypothalamus will sense that and get the signal warthat ning we are losing all the fuel reserves. So your brain will switch the hunger up again. But how does it do it?
By increasing another hormone called ghrelin. So ghrelin is the hunger hormone in our bodies. That is the one that will make you crave food, particularly high-calorie food. So the more fat you lose, the more hunger you will have. And this is a self-preservation mechanism your body has. Think of it like the thermostat in the house. When the house gets cold, the thermostats will kick in. The boiler will fire up, and the house will warm up again by raising the temperature inside the pipes. The body does the same. When fat stores fall, hunger kicks in to bring your fat levels back to what your brain will perceive as the normal level.
Now, let’s flip things around. Let’s say you have a big party dinner, lots of barbecue, lots of meat, and different types of food, and you are feeling full, really full. What would happen the next day? And intentionally, you will find that you don’t feel like eating much the next day. And that is exactly the opposite mechanism. This is why most diets eventually feel harder. Not because you have failed, but because your biology is doing exactly what it’s meant to do. It’s protecting you from losing your fat reserves.
Let’s go back to the analogy I used in a previous blog. Imagine your body as a wooden house. There’s a fireplace inside. That’s your metabolism. And each day you receive a delivery of woodlocks. That’s the food you eat. Now, let’s talk about two scenarios. In the first scenario, you are getting too many woodlocks. What do you do? You throw extra logs on the fire. Let it burn hotter. Let the house be so warm that there is no problem. And when there is more than you could burn, you store the extra logs in the corners of the house, just like your body stores the fat in different parts of it.
Now, in the second scenario, your deliveries shrink. The truck driver who brings the woodlocks may be off sick, so they mayn’t deliver the woodlocks to you every day. So what are you going to do? You’re going to try to burn fewer logs in the day. Your body does the same when you are on a diet because the body will sense a shortage of food. So what it will try to do, it will try to drop the use of the energy that comes from the food by reducing your basal metabolic rate. That’s the energy that you burn at rest just to keep you alive. As you saw in the last video, the basal metabolic rate makes up a big proportion of the energy use, making up to 70 to 75% of your energy use.
Case study - what really happens
One of the most striking examples comes from a landmark study by Professor Rudy Leel at Columbia University. He published his findings in the New England Journal of Medicine, which is one of the most prestigious medical journals. So what he did was he followed a group of healthy volunteers under very strict conditions in the hospital. So they lived in his hospital, and he was providing them with food that was well monitored, and he kept an eye on them for 2 years. In the first period, he overfed them, and what he noticed was that all the volunteers had gained weight and their basal metabolic rate went up as they gained weight, as the body was trying to burn off all that excessive food that they had eaten. And then what he did was to put them on a calorie-restrictive diet. And then what he noticed is that as they started to lose weight, their basal metabolic rate dropped a lot. This is the body adjusting how much energy it uses at rest, which makes the most of the energy the body has going up and down based on how much food these volunteers have been taking in. And this is a very powerful tool that the body has to adjust and adapt to the food intake. So here is what the data showed.
When people lost about 10% of their body weight, their basal metabolic rate dropped by about 250 calories per day. And this was the mechanism by which the body would reduce how much energy you use at rest. So it will counteract the effect of you not eating as much. For those who lost about 20% of the extra weight, the basal metabolic rate dropped by about 300 calories. If you think about it, this is roughly the same energy you would burn if you do a 30 to 40-minute workout every day. That’s just your body simply cancelling it out by reducing your basal metabolic rate. So why does the body do this?
It’s trying to defend its fat storage. So even if you are eating less, your body is adjusting behind the scenes, burning less, conserving more. And when you combine that with the increased hunger we talked about earlier, you’re not just fighting your appetite, you are fighting your metabolism too. This is why so many people hit a plateau in their diet. It’s not because they have slipped through or started cheating. It’s not laziness. It is a metabolic adaptation. Your body is doing exactly what it is meant to do, protecting you. And it does that by keeping your weight within a range it believes to be a safe range. That range is now widely known as the weight set point.
So now we have uncovered the two ways your body fights back during your weight loss journey. This is not failure. It’s your body defending itself like it always has by holding onto the fat stores for survival. But here is the big question. What is it defending? Why that specific weight and not lower? It all comes down to something called the weight set point. This is your brain’s internal idea of what your normal weight should be. It’s not based on your goals. It’s not about your health. It’s not even about logic. It’s all about biology. The weight set point is shaped by a mix of factors. your genes, your previous diet history, especially your dieting, your sleep pattern, your stress level, your food habits, and years of food restrictions. All these play a role in controlling and deciding how your brain perceives what your safe, normal range of weight should be. Most people already know what their weight set point is because it is that frustrating weight range your body keeps drifting back to whenever you try to lose weight. So the real question is, can it be changed? In the next post, we will dive into how the weight set point works and how you can reprogram it. Because until you understand the set point, you’re not just dieting against your habits, you are dieting against your brain.