Freeze your nerves to shed the excess pounds? That’s the idea behind a recent approach that might hold notable weight loss results. Freezing the nerve responsible for carrying hunger signals to the brain could help people with mild-to-moderate obesity shed some weight.
According to radiology and imaging sciences from the Society of Interventional Radiology, the treatment is deemed feasible and safe in its first pilot phase. But, does it have what it takes to help patients slim down in the long run? Here is what experts have to say. (1)
Complicated Factors Behind Obesity
In the last 40 years, the prevalence of obesity has tripled. Studies indicate that roughly 15% to 40% of adults with inflammatory bowel disease are obese. And an extra 20% to 40% are overweight. (2)
This obesity epidemic has had a drastic impact on people’s quality of life and their ability to lose weight. The simple explanation for the global spike in obesity cases and excess body mass index is that people prefer to eat meals packed with calories and fat.
They don’t exercise enough nor try to limit calories to ease their digestive and kidney diseases. Instead, many would rather enjoy processed goodies with extra salt and sugar. Just because they make them feel good. Like high fructose corn syrup, for example.
This syrup is sweeter, cheaper, and gets absorbed much faster into the system. Eating it in high amounts can lead to obesity, elevated blood pressure, diabetes, and insulin resistance. It isn’t until obese patients get to a critical point in life that they want to lose weight and fast.
But, it’s not that simple to reverse weight gain. There is no magic pill that will make the extra pounds go away. According to experts, obese and overweight individuals hold remarkably different views on physical activity and diet compared to those with normal weight. (3)
The flavor of the food is their top consideration when picking out what to eat. They rarely observe the nutritional labels on the products they buy. For obese or overweight patient, their relationship with food and hunger cues are more emotional and impulsive.
This is the food reward system. When a person acts on their cravings, their central nervous system gets a reward. The food reward provides feelings of pleasure due to the temporary dopamine release. And while many would be open to implementing some dietary restrictions, it is very difficult to keep up with these efforts.
Here is why.
Over time, the body resists. Because people have become so used to the addictive qualities in certain foods, it becomes a real problem to tackle unhealthy eating habits. Leptin is an appetite hormone that’s crucial in regulating the diet. Created by fat cells, this molecule sends signals to the hypothalamus (a region of the brain), which controls the cravings the moment our energy stores get full. (4)
But, as we pile a few extra pounds, our body becomes less sensitive to leptin. Thus, making it difficult to regulate the energy metabolism and shed extra weight. Since leptin was discovered, back in the 90s, there has been a surge in obesity research.
This hormone can help us better understand the condition and the factors that impact overall weight. Then there is ghrelin. This appetite increaser is released mainly in the stomach. It causes a hunger response.
You would expect the body to trigger ghrelin release if you are undereating, like taking fewer calories or drinking your favorite diet beverages. And decrease it if you eat too much. Sure enough, ghrelin levels spike in children with anorexia nervosa and drop in obese children.
The fact is, ghrelin plays a fundamental role in determining how soon the hunger comes rolling back after your last bite. Of the two hormones, leptin, which is the one that suppresses the appetite, seems to have the most impactful role in energy balance. And it can regulate ghrelin. (5)
The problem with obesity and associated diseases is that obese patients don’t respond well to leptin signals. Despite their spike in leptin levels. A diet rich in protein or good carbs (i.e. whole grains) suppresses ghrelin better than a high-fat diet.
When people start any diet, their system and brain begin conspiring to sabotage all their hard-earned efforts. In the first 30 to 60 days, the body fights itself, all because it thinks it is starving. While in fact, it isn’t. Nevertheless, the processes begin to slow down. Resulting in 10 to 15 different factors that block weight loss.
For many, this is an obstacle that’s impossible to overcome. Some can handle one to two weeks of their diet. While others tend to give up halfway through. So, to slim down efficiently it is important to target obesity in the brain – not just the belly. It’s vital to focus on the body’s backlash to achieve practical weight loss results.
Freezing Hunger Signals: How Does It Work?
Along with the skyrocketing numbers came a soaring interest in dieting and fitness attempts. All the effort is placed into losing weight. Improving fitness, increasing physical activity, and supplying the body with a balanced diet remain the healthiest and safest weight loss approaches.
Recently, however, experts have looked into a different tactic – freezing the nerve that hauls hunger signals to the brain. Wondering which nerve carries hunger signals to the brain? That would be the vagus nerve.
This is the longest cranial nerve in the human system. It oversees crucial bodily functions. Not only does it regulate gut physiology, but it also gets involved in controlling respiratory, endocrine, cardiovascular, and immune systems. (6)
To date, its role in appetite regulation and obesity control has been recognized. It involves a complicated interplay between peripheral and central mechanisms. All of which use vagus nerve fibers. That’s why the vagus nerve can affect your appetite, sickness, and mood behavior. (7)
But, this is not the first time the vagus nerve was studied for conditions related to obesity. Based on 2019 reports, vagus nerve stimulation showed a drastic decrease in rheumatoid arthritis (RA) symptoms. (8)
Obesity and overweight are typical risk factors for RA. While arthritis can make some people gain weight, it can also lead to unexpected weight loss. Experts estimate that 2/3 of people with RA are obese or overweight. Weight loss could also be an adverse reaction of RA medications or a symptom of the ailment itself. (9)
Does Vagus Nerve Reduce Weight?
The communication between the brain and the gut is a key factor in controlling energy homeostasis. Energy homeostasis is a biological process that involves the coordinated response of energy flow (food intake) and energy outflow (energy expenditure). 50% of the energy from glucose metabolism is quickly converted to heat.
When you eat food, enteroendocrine cells start secreting gut hormones. These hormones can suppress your appetite. A 2018 clinical trial explains that the vagus nerve remains a key component in transmitting these signals, which are supposed to travel from the gastrointestinal tract to the central nervous system. (10)
Many of the gut hormones that the enteroendocrine cells secrete, rely on the vagus nerve to pass their signals. David Prologo, an interventional radiologist and lead author of the freezing hunger signals study stated they developed a treatment for patients who are moderately obese.
The goal was to decrease the attrition that is highly prevalent with weight loss efforts. So that people can succeed in their attempts to slim down. During the treatment, an interventional radiologist will insert a needle through the back.
With the help of live CT scan images, the interventional radiologist will use argon gas to freeze the nerve, typically referred to as the posterior vagal trunk. This is a branch of the vagus nerve. It consists mainly of fibers from the right vagus. But also features a couple of fibers from the left vagus.
Potential Success Rate of Freezing Hunger-Signals
In the study, 10 patients with a BMI (body mass index) from 30 – 37 took the vagus nerve freezing procedure. They were analyzed for the next 90 days. All the study participants reported decreased hunger. Including an overall weight loss of 3.6% of initial body weight on average. And a decline of almost 14% of the extra BMI.
It takes 2 min to freeze the hunger nerve at -40 °C. The injection area is a 1 cm by 2 cm segment close to that junction, stated Prologo.
Based on the initial analysis, volunteers didn’t develop any significant procedure-related complications. No adverse events occurred during the follow-up period. Most weight loss and exercise programs fail. Particularly when a patient is trying to curb the amount of food they eat.
When our stomach is growling, the body triggers a hunger signal, which is basically a switch for our food-seeking survival mode. The nerve freezing treatment is not meant to get rid of this biological response. But to decrease the hunger signals’ impact on the brain. And offer a novel, sustainable solution that would mitigate the effects of mild obesity.
Take Jessica Knight’s example. Patient Jessica Knight tried every possible diet she could get her hands on. She tried anything from mail-order boxed meals to a low-carb diet. She wanted to get rid of 50 pounds and curb her BMI, which was back then, within the obese range. (11)
However, she was quickly losing hope. Any weight loss tool she tried never seemed to last. To make matters worse, she was working at a desk job, which meant she had to sit all day. That’s until her sister, a nurse working at Emory Johns Creek Hospital, informed her about a feasibility study for weight loss.
David Prologo together with a team of board certified experts enlisted a couple of men and women for the procedure that takes around 30 min. The patient is first sedated, after which a needle, filled with freezing gas is inserted. By freezing the vagus nerve, it’s possible to create an ablation zone.
This zone is capable of shutting down or stopping the signals in the hunger nerve to the brain. Patient Jessica Knight stated that needles scare her out of her mind. But, decided to go through with the treatment, if it meant decreasing her body weight. (12)
She explained that during the freezing of the hunger nerve she felt as though she was in a dream-like state. She later checked the injected area. But, couldn’t see any visible signs. Just a little tender between the shoulder blades. While a band-aid covered the spot.
The first week after treatment, Knight didn’t notice any significant changes. Then, she slowly realized she was cutting down her food portions. And was more eager to exercise. She stated she couldn’t finish an entire portion. For example, she could munch on half a cheeseburger and feel full relatively quickly.
This is what happened to all the participants of the study. In about 6 months after the procedure, people reported a drop in hunger at 95% of their follow-up contacts. The majority of them explained that they ate less compared to what they normally would.
It’s crucial to point out that participants weren’t asked to follow any calorie restriction guidelines or physical activity. Mainly to see if the treatment was safe. To establish viable weight control results, participants were asked to listen to their bodies and observe the effects of the nerve indicating hunger.
Surprisingly, Knight stated she craves healthy foods. If she tries to eat anything other than that, like eating cake, she feels terrible afterward. What used to feel like torture back when her unhealthy cravings would take over, is now much easier to navigate. She still has to make conscious choices to eat healthy foods. But, it is easier to make these choices and avoid weight gain.
After 8 months post-treatment, she shed 30 pounds. Knight recently visited Australia and went snorkeling and hiking. She has experienced a drastic change in weight and her entire attitude towards weight loss. Instead of obsessing about how much she weighs, she is more focused on the way she feels. (13)
There is nothing to be ashamed about if you can’t lose weight, explains Prologo. The problem is, there is a huge biological backlash that occurs the moment people embark on mainstream diets. It has nothing to do with weakness. (14)
Prologo’s own mother struggled with weight gain. She raised 3 boys, attended night school, and dealt with many financial burdens along the way. She even had to take care of her own sick parents. But, no matter how hard she tried, she couldn’t find a practical way that meant losing weight.
Many critics say that people can’t handle obesity management because they don’t have the perseverance or willpower to do it. But, there is more to weight gain than meets the eye. And has nothing to do with personal weakness. By freezing the hunger signal, you can trick the body into cooperating with the participant.
The patients in Prologo’s study lost weight. They managed to curb their initial total weight without the unnecessary side effects. However, more data is necessary to evaluate the treatment’s efficiency, durability, and probable limitations. Because of how successful the study turned out to be, Prologo is planning another study that would prove the procedure’s effectiveness. (15)
A huge chunk of the population is struggling with obesity. Exercise and healthy eating still remain key factors in staying fit. Recently, however, another treatment gained momentum. Although still in its early phases, it seems that freezing the hunger signal can help people make healthier food choices and stick to an active lifestyle.
Based on the preliminary data, this treatment makes the weight reduction go smoother. For those who’ve struggled with cravings, it surely seems like a feasible option to gain remarkable results. But, more research is necessary. That’s why experts behind it are planning another study to further prove its efficacy. Until then, consult with a doctor to incorporate healthy eating, exercise, and adequate medication if necessary for treating disorders.