25.08.2024 Polish Food Day – to eat or not to eat? That is the question!

Modern societies have been overwhelmed by the fashion for losing weight. This is a response to the obesity pandemic of our times and the growing awareness of its negative health consequences. According to the World Health Organisation (WHO), in 2022, one in eight people worldwide were living with obesity (BMI > 30), amounting to nearly one billion people. Obesity is not only a disease in itself, but contributes to the development of many other diseases such as cardiovascular disease, type II diabetes or even cancer. Already Hippocrates, around 400 BC, noted that obese people are at greater risk of sudden death. Paradoxically, globally, more people die from excess food and related diseases than from malnutrition. So what can be done to counteract obesity?

New diets or eating regimes are proposed to us from various sources, often with nothing to do with the scientific approach. Diets based only on fats, or on carbohydrates, high in fibre or easy to digest, skipping breakfast or dinner, eating only within a certain time window, fasting ourselves for a second day, and so on. Apart from the side-effects of some diets, the effects of these weight-loss measures are generally insufficient and, especially in the long term, we find it difficult to maintain the reduced weight. Despite scientific advances, the most effective method of permanent weight loss in the fight against obesity is still surgical bariatric intervention, or in simple terms, gastric reduction. Recently, a great deal of hope has been brought by drugs, originally antidiabetic, used in the fight against obesity, the so-called GLP-1 receptor agonists, which in a way prepare the body for the influx of glucose into the blood and suppress the appetite. Nevertheless, their use is at the beginning of the road and it remains to be seen whether their use is completely safe.

Why is it so difficult to lose weight? The answer to this question lies in the evolution of our brain. We must remember that for the vast majority of man’s time on earth, our brains developed under conditions that were extremely different from those in which we live today. This mainly relates to the widespread availability of high-calorie foods, a sedentary lifestyle and chronic stress. In order to understand how our brains worked and still work (the agricultural revolution took place only 10 000 years ago), we need to look at what life was like for our ancestors who lived a hunter-gatherer lifestyle. First of all, they were faced with periodic shortages of food, so that the feeling of hunger dominated over the feeling of satiety and triggered an active search for food. In addition, when there was an excess of food, e.g. after hunting an animal, the body switched to storing as much energy as possible in adipose tissue. Finally, stress, although sometimes very strong, was rather short-lived. Nowadays, chronic stress generally causes negative metabolic changes. It can therefore be seen that, in order to achieve long-term weight loss, we need to overcome at least three systems present in our brains: the hunger and satiety system, the reward system and the stress-response system, specialised in the opposite activity to weight, i.e. energy loss. It should also be noted that the diet of primitive people did not contain a combination of simple sugars (honey, fruit) and fats (hunted game or fish), which is now found in almost every meal and essentially increases the rate of weight gain.

This type of issue, i.e. how the brain regulates our eating behaviour, both in the context of neuropsychiatric diseases such as anorexia and obesity, is dealt with by the Neuroplasticity and Metabolism Research Group at PORT Polish Center for Technology Development, led by Dr Witold Konopka.