Obesity has become a growing issue worldwide, and it often comes with various health problems such as diabetes, high blood pressure, and high cholesterol. However, not all obese individuals experience these complications. In fact, some people who are obese remain healthy, without any signs of metabolic diseases. This has puzzled scientists for years. A recent study conducted by researchers from the Swiss Federal Institute of Technology in Zurich and the University of Leipzig has shed new light on this mystery. The study reveals differences in the cells that make up body fat in healthy obese people and those with obesity-related diseases. By analyzing these differences, the researchers have created a detailed map that shows how obesity affects our fat cells and contributes to health outcomes.
The Study: Understanding Obesity at the Cellular Level
Obesity is often seen as a direct cause of metabolic diseases. However, as this new study shows, the relationship between obesity and health is much more complex. Researchers aimed to explore why some obese individuals develop health problems, while others do not. To do this, they used tissue samples from the Leipzig Obesity Bank, a biobank that collects biopsies of fat tissue from obese individuals. These samples come from patients who agreed to provide their tissue after undergoing elective surgeries. Along with these samples, the researchers also had access to detailed health information about the patients.
The study focused on two types of fat tissue: subcutaneous fat (the fat located directly under the skin) and visceral fat (the fat that surrounds internal organs, such as the liver, pancreas, and intestines). While it is well-known that visceral fat is associated with a higher risk of metabolic diseases, subcutaneous fat is generally considered to be less harmful. The researchers used these tissue samples from 70 volunteers, comparing the differences in fat tissue between those who were obese but healthy and those who had obesity-related diseases.
The Differences Between Healthy Obesity and Metabolic Disease
The researchers found key differences between healthy obese individuals and those with metabolic diseases at the cellular level. One of the most significant findings was that visceral fat cells (those surrounding internal organs) in obese individuals with metabolic diseases showed severe dysfunction. These cells were no longer able to burn fat efficiently and instead released higher levels of immunological molecules called cytokines. Cytokines are proteins that play a major role in regulating the immune system, and when produced in excess, they can lead to inflammation and contribute to the development of metabolic diseases.
The study also revealed differences in the number and function of mesothelial cells, which are a type of cell found in the tissue surrounding internal organs. Mesothelial cells play an important role in protecting the organs and facilitating the smooth movement of tissues. In obese individuals without metabolic diseases, there were significantly more mesothelial cells in visceral fat compared to those with obesity-related diseases. These mesothelial cells in healthy obese individuals displayed high functional plasticity, meaning they could change into other types of cells, including stem cells. This ability to transform into different cell types could help explain why some obese individuals remain healthy, as these cells might play a protective role in preventing metabolic disease.
The Role of Visceral Fat in Metabolic Diseases
One of the key takeaways from this study is the role of visceral fat in the development of metabolic diseases. Visceral fat is deep within the body and surrounds vital organs. This type of fat is much more dangerous than subcutaneous fat, which sits just under the skin. The cells in visceral fat have a higher tendency to become dysfunctional in obese individuals with metabolic diseases. They cannot burn fat effectively and instead contribute to inflammation by releasing cytokines. This chronic inflammation is one of the main factors that can lead to diseases like diabetes, high blood pressure, and heart disease.
In contrast, subcutaneous fat seems to have a less harmful effect on the body. The fat cells under the skin, while still storing excess energy, do not contribute to inflammation or interfere with the function of internal organs as visceral fat does. This is why some obese individuals who carry more subcutaneous fat may not experience the same health problems as those with excessive visceral fat.
Why Some Obese People Stay Healthy
The study’s findings help explain why some obese individuals remain healthy. It appears that the presence of mesothelial cells in visceral fat plays a protective role in preventing metabolic diseases. These cells are able to transform into other cell types, including stem cells, which could help repair damage caused by inflammation or improve fat metabolism. In healthy obese individuals, the mesothelial cells in visceral fat may be better at maintaining normal fat function and preventing the harmful effects of inflammation.
Additionally, the study suggests that not all fat is the same. While visceral fat is dangerous and contributes to disease, subcutaneous fat may not have the same harmful effects. The cells in subcutaneous fat may be more efficient at storing fat and less likely to become inflamed or dysfunctional.
Implications for Obesity Treatment
This new understanding of how fat cells function could have significant implications for the treatment and management of obesity. By focusing on the differences between visceral and subcutaneous fat, doctors may be able to better identify individuals at risk of developing metabolic diseases. For example, individuals with large amounts of visceral fat could be more closely monitored for signs of disease, while those with mostly subcutaneous fat may require less intervention.
Moreover, the discovery of mesothelial cells’ role in protecting against metabolic diseases suggests that therapies aimed at promoting the activity or number of these cells could help prevent or reverse obesity-related diseases. Research into fat cell regeneration or the use of stem cell-based therapies might one day offer new treatments for people with obesity who are at risk of metabolic diseases.
Conclusion: Can You Be Fat and Healthy?
The study from the Swiss Federal Institute of Technology and the University of Leipzig provides new insights into the relationship between obesity and health. It shows that not all fat is the same and that the type of fat—whether subcutaneous or visceral—plays a significant role in determining whether an obese person is healthy or at risk for metabolic diseases.
While visceral fat is linked to inflammation and metabolic diseases, subcutaneous fat seems to be less harmful. Additionally, mesothelial cells in visceral fat may provide a protective effect, helping some obese individuals avoid the negative health consequences of excess weight. This research opens up new possibilities for treating obesity and preventing obesity-related diseases by targeting specific fat cells and promoting healthier fat function.
In the future, scientists may be able to develop more targeted treatments to help obese individuals stay healthy or reduce their risk of metabolic diseases. However, the most effective way to manage obesity and prevent associated diseases is still a healthy lifestyle, including a balanced diet and regular exercise.