Obesity is the disturbed mechanism of body energy homeostasis

A Nat-Pol study from 10 years ago found that 22 percent of the Polish adult population was obese. At the same time, it was estimated that the percentage would rise to 33 percent within 15 years. Are these predictions coming true?

It is very difficult to conduct epidemiological studies that allow us to accurately assess the prevalence of obesity-related disease. Why? Firstly, it results from the methodology of the conducted research. We will get different results when we rely on declarative data and different when we rely on measured data. It is known that respondents tend to underestimate their body weight - declarative surveys are therefore not very accurate. Tests performed on the basis of measurement results will be reliable. However, carrying them out on a large population is quite difficult. It is also worth noting that the body weight indicated by the scale at any given moment is not given to us for life. It fluctuates even within a day, and certainly within a week, a month, and a year. Another important point is that we use BMI in the classification of obesity. It is essential to emphasize that it is not perfect. It is assumed that a BMI above 30 indicates obesity.  And this is not always true. We can talk about the disease of obesity only when we are dealing with disorders of body homeostasis leading to excessive accumulation of adipose tissue. Meanwhile, not so rarely, it happens that excessive body weight does not result from excessive accumulation of body fat, but from very well developed muscle tissue. Thus, we can only talk about the prevalence of obesity-related disease with a good approximation. I think that it will not be wrong if we estimate that at the moment every fourth adult in Poland suffers from obesity.

And is there any current research on this?

Yes, and it is conducted at our university. It is handled by a team led by Professor Boleslaw Samolinski from the Department of Prevention of Environmental Hazards,  Allergology and Immunology, as part of the National Health Program. The research was conducted between 2017 and 2020. Possibly it will bring us closer to answering the question about the prevalence of obesity. However, the results are still to be seen. They are currently being compiled.

You deal with the surgical treatment of obesity, so you mainly see people with morbid obesity…

Surgical treatment of obesity, or so-called bariatric surgery, is a therapeutic procedure designed for people with the most advanced forms of obesity disease, i.e. with so-called giant obesity. These are the patients with a BMI above 40 or above 35 - if obesity is accompanied by complications such as type 2 diabetes, hypertension and others, in a total of about 200. Bariatric surgery may also be considered when we have a patient with type 2 diabetes and a BMI between 30 and 35 in whom, despite intensive conservative treatment, the therapeutic goals are not achieved, for example, weight gain is observed.  

How many Polish people have indications for this treatment method?

This is estimated to be about 1 to 2 percent of our adult population, that is, the portion that suffers from morbid obesity, but given that the indications also include patients with lower BMIs, it could mean a total of 1.5 million people nationwide.

A common belief is that obese patients accumulate excess body fat because they eat too much, move too little, and lack willpower. You fight against this view. Why?

I am not fighting. I am trying to communicate to a wider range of people, including medical professionals and doctors, the results of scientific research in recent years. Most views about the development of obesity-related disease are stereotypes based on beliefs rather than scientific results. And the commonly expressed opinion about the causes of the development of obesity "they eat too much, move too little, that's why they are fat" has no scientific basis today, and is additionally a discriminatory and stigmatizing statement.

So what is the truth?

We don't have full knowledge of this yet. I'm not sure there's any chance at all in the coming years that we'll get a complete picture of the causes of obesity. However, some things we already know. First and foremost is the fact that obese patients have an abnormal secretion of certain hormones. These hormones are produced in the digestive tract, and they affect the central nervous system and determine what decisions the brain makes when it comes to food intake. We have findings from several years ago which show that patients with giant obesity lack postprandial GLP1 secretion. It is a hormone secreted in the small intestine. When it reaches our brain it sends the message: "Move the plate away, don't eat." A simple conclusion comes from this: People suffering from giant obesity, but also those suffering from less severe obesity, do not eat a lot because they lack willpower, they just don't feel satiated. They are not obese, because they eat a lot. They eat too much because they suffer from obesity, i.e., a disorder of the neurohormonal regulation of food intake.

In a healthy body, we have a self-regulatory mechanism: we eat when we are hungry and until we feel satiated...

This is what is called homeostasis, and this is the basis of our lives. The entire body is subject to homeostatic mechanisms. We talk about homeostasis of thyroid hormones, sodium, potassium, clotting factors, we also have energy homeostasis of the body. The latter, is like the internal scale. The problem is that the mechanisms of energy homeostasis arose in an energy deficient environment. Our body has developed numerous ways over tens of thousands of years to store energy, and none to get rid of it easily. Nowadays, when there is too much energy around us and it is easy to get it (because you don't have to run after a mammoth, you just pick up a cart at the supermarket), energy homeostasis is more easily disrupted. To me, obesity disease is precisely the disrupted mechanisms of energy homeostasis in the body that lead to the development of the primary symptom of obesity disease, which is the excessive accumulation of body fat, or obesity.

Since from the beginning we all have self-regulating appetite mechanisms, why does energy homeostasis exist in some and become disrupted in others?

I think in this case it's like with any disease. We have a predisposition and a trigger factor. The triggering factor is certainly the obesitogenic environment that promotes the development of this disease. It's all about the excess energy, the ease of obtaining it, and the low energy expenditure involved in getting it.

Obesity patients often hear that they are to blame...

I would very much like to emphasize that this is not the fault of the ill. Let's finally remove the guilt from obesity patients. Nobody chose this disease. This stereotypical view has very dangerous consequences for this group of patients. Obesity-related disease is underestimated and, as a result, goes unrecognized. Studies from the United States of America indicate that 50 to 75 percent of patients have undiagnosed obesity disease. I think it is even worse in our country.

What are the implications of this?

If the condition is not recognized, it goes untreated and complications develop as a result. Interestingly, obesity is perhaps the only case in medicine that more emphasis is placed on treating complications than on treating the underlying disease. If we take the information sheets from the internal medicine wards, we can often find the following diagnoses on them: type 2 diabetes, hypertension, steatohepatitis, coronary artery disease, degenerative changes in the spine, and finally obesity. Meanwhile, we should really be talking about obesity complicated by type 2 diabetes, obesity complicated by hypertension, obesity complicated by steatohepatitis, etc.

One effective treatment for obesity is bariatric surgery. How does it work?

The effectiveness of surgical treatment of obesity is estimated at 80-90 percent. Our long-term observations show that patients with bariatric surgery have a decrease in body weight, but most importantly, the risk of death decreases. I like to refer to Arterburn's research. According to them, for every 100 people suffering from giant obesity during a 10-year follow-up period, if they are not operated on - 24 will die, and if they are operated on – 14. This means that for every 100 patients we qualify for surgery, we can save 10 lives. And if we relate that to the 1.5 million people with giant obesity in our nation's population, that means 150,000 lives saved or lost if we abandon this treatment. And how does it work? We used to think that bariatric surgery was effective because we shrink the stomach and as a result the patient can eat less or we shorten the intestines and not everything they eat will be absorbed. We now know that the principle of bariatric surgeries is different. They repair disrupted mechanisms of neurohormonal regulation of food intake. We know from a 2009 study that when we do sleeve gastrectomy, we observe a decrease in ghrelin levels in patients. This is a hormone secreted within the part of the stomach that is being removed. It pushes us to eat. By performing bariatric surgery, we reduce the secretion of this hormone. Later, when patients come to us for follow-up, they say they don't feel hungry after the procedure. In contrast, before surgery, they spent 80 to 90 percent of their day thinking about food. It was a constant struggle between "to eat and not to eat".  

You mentioned that we have 1.5 million patients requiring bariatric surgery

It's not really the case that 1.5 million patients need to have surgery. Certainly, however, these individuals need to be diagnosed and treated. Among the methods of treating obesity today, in addition to bariatric surgery, we have pharmacotherapy, nutrition education, motivation by psychologists, behavioral management, that is, work on changing behavior. We should take all these elements into account and strive for the so-called comprehensive treatment. I recommend the book "Obesity and its Complications" to anyone interested in obesity issues. One of its co-editors is Prof. Artur Mamcarz from our University. The book was published in late October under the auspices of the Polish Society for the Treatment of Obesity.

The interview was conducted by Iwona Kołakowska, MUW