Have you ever gone on a diet only to regain the weight you lost? Do you find that even when you are sticking to your diet and exercising, that your body sometimes just won’t lose weight? Have you ever had to fight through insane hunger and cravings? If so, the reasons behind these situations may be much more fundamental than most of us realize.
Many have dealt with scenarios like those mentioned above. It is a remarkably frustrating experience that, often, can drive you to abandon your attempts to achieve a healthy you. But, it doesn’t have to be that way. Understanding what is going on in your brain through the process of weight loss can dispel some of the mystery of why the body reacts like it does. Let’s take a look at the epicenter of all this cranial drama.
Your Ancient Brain: The Hypothalamus:
The Hypothalamus is a small section of the brain. It helps to regulate many basic life functions including temperature, electrolyte balance, sleep and wake states, hunger, body fat level, sexual behavior, etc. By noting that distantly related species all have a hypothalamus, from the smallest creatures to humans, we can deduce that this common feature was maintained through evolution thus making it one of the oldest areas of the brain. Yet it is also one of the smallest sections of the brain weighing just 4 grams of a 1400 gram human brain.
The best description I have seen refers to the hypothalamus as a thermostat in your brain that regulates certain body parameters. As signals from throughout the body make their way to the hypothalamus, it compares the received information to pre-programmed ideal values, most often referred to as “set-points”. When a signal deviates from a set-point the hypothalamus initiates a process called homeostasis to compensate and restore the body to its set-point.
How does the hypothalamus affect weight?
In the case of weight and body fat levels, the hypothalamus measures body fat using leptin, which is secreted in your blood stream in proportion to the amount of fat you carry. This is the method in which signals are carried to the hypothalamus such that it can react to changes in your body. As you lose weight, the amount of leptin in your bloodstream decreases. This sends a signal to the hypothalamus that initiates a response upping hunger and making you eat. In essence, it is a starvation response.
In an article on the hypothalamus at blog.humanos.me, the author compares the weight regulation process to a seesaw, which has a program on one side to increase fat stores, and a program on the other to decrease fat stores. Leptin affects both programs, so as you lose fat, the absence of leptin shifts the balance to increase fat storage. This is one of the primary reasons why people regain fat after losing it – or why I have often described my diet as having a slow seesaw effect. It’s because the physiological process IS a seesaw!
However, if this process were working properly, the theory would hold that it would be hard to gain weight too! Your body would be regulated to a given set-point. So to understand why we gain weight despite this mechanism we need to address leptin resistance.
When there is a communication problem with the brain reading leptin levels, then this is referred to as leptin resistance. This could be because leptin is not getting across the blood-brain barrier, or the hypothalamus has become insensitive to leptin readings. This inability to accurately read leptin results in a mismatch between hypothalamus input to your brain and what is required by the body – hence stubborn and consistent weight gain.
According to Dan Pardi, MS and Stephan Guyanet, PhD in their article on leptin and the hypothalamus: “A variety of lifestyle factors may affect leptin resistance, including sleep fragmentation, inactivity, calorie surplus and certain levels of dietary fat. Researchers believe that resistance to leptin is caused by an increase in inflammation and stress in the brain. This process is thought to contribute to an elevated body fat set point.”
It’s important to note here that the researchers are plainly saying that what contributes to inflammation and stress in the brain are lifestyle factors like high fat diets, lack of exercise, emotional eating, high stress environments, etc. Therefore, the act of losing weight and keeping it off is made physiologically difficult by the brain being resistant to leptin.
Remodeling through neuron replacement:
The working elements of the hypothalamus, and thus your body weight set point is constantly remodeled by the production of neurons. New neurons replace old ones and when they are produced, they come in with a new understanding of where the body is in the weight regulation process. Researchers have also noted that in animal models of diet induced obesity that replacement of old neurons with new ones is suppressed, which may explain an elevated weight set point.
This points directly to our diets as a major contributing factor to both healthy weight set points and elevated weight set points, and likely, to leptin resistance. It seems clear, from the research, that the diet used during the weight loss journey has a direct effect on the amount of neuron remodeling in the hypothalamus.
This has long-term implications for how successful you are at maintaining weight loss progress and explains why not all weight loss regimens are successful over the long term. In other words, this is medical evidence why FAD DIETS DON’T WORK. It also helps to explain yo-yo dieting, why your brain makes you cheat on your diet, and why it is generally hard to lose weight and maintain a healthy weight. It also has implications on how stress plays a part in weight retention.
The 10,000 foot view:
I’m going to take a moment and divert our focused approach on the medical science for a brief look at the bigger picture. The above information, if it’s new to you, explains a lot for those of us who have been obese for the majority of our lives. These processes have been key in why we remain obese year after year.
How the hypothalamus operates, leptin resistance and the impact it has on our day-to-day lives makes it abundantly clear why we have struggled to maintain a healthy weight. We have a lot working against us …even our own brains. It’s equally clear why an understanding of this process can help us to defeat the hunger, cravings and hurdles. This turned into an “ah-ha!” moment for me and showed me the value of determination and commitment to my plan.
It’s ok for your diet to have plateaus. And it is perfectly normal for your body to just “decide” it is not going to lose weight this week, despite the fact that you have adhered to you diet. We have to accept these realities as byproducts of the cause and effect system that is inherent in the hypothalamus, and thus our own brains. We must remain dedicated to a longer term effort and need to retrain our brain to think thin!
Train the brain to happy with a lower set point:
Training your brain to be happy at a lower weight set point is a slow and intentional process. You have to know what you are doing and what you will encounter. The research, while far from conclusive, seems to indicate that lifestyle and diet are the major contributors to being able to make a weight loss program work and maintain weight loss. If your diet and lifestyle can help you lower stress and inflammation in the hypothalamus, remedy leptin resistance, and subsequently promote neuron remodeling, then, in theory, you should have a winning combination.
While there is little research supporting what specific diet leads to these results, it is my suspicion that a clean, low calorie diet of simple, whole foods is likely the best bet. Eschewing refined and processed foods and along with a moderate and healthy exercise regimen should be a key to long term success in training your brain to maintain a new weight comfortably.
There is a lot of information here, and probably some new concepts to a few of you. Don’t be intimidated or overwhelmed. Now we know why dieting is so difficult. We have learned that it’s not just the fat we are fighting. It is also how our minds operate and those stubborn set-points! In addition, now we also have an idea of the contributing factors to our body’s resistance to lose weight! These are huge pieces of knowledge!
Armed with this new knowledge, be confident in your program. Understand that the battle we are fighting is bigger than just losing weight. It’s an entire lifestyle remodeling process! Dedication, sustainability, consistency and perseverance will help us retrain our brains to think thin!
Find more information on my system and healthy diets here.