Overweight and obesity are defined by the World Health Organization (WHO) as the abnormal or excessive accumulation of fat that poses a health risk. According to the WHO, approximately 35% of the world’s population is estimated to be overweight (body mass index, BMI 25–30 kg/m2) or obese (BMI > 30 kg/m2). Body mass index (BMI) is recognized as a valid measure of body fat percentage. Normal weight is determined by the condition BMI < 25Kg/m2.
“It is well known that obese individuals exhibit a subclinical chronic inflammatory state that leads to multiple metabolic disorders,” she points out. Mrs. Eleni Komninou Rheumatologist Director of Autoimmune Rheumatic Diseases Clinic Metropolitan General.
“For several decades, industrialized countries have faced a particularly increased incidence (prevalence) of autoimmune diseases.
Among the causes of these inflammatory diseases is the interaction between genetic background and multiple environmental factors. Since the genetic basis has remained stable over time, it is increasingly recognized that environmental factors, especially the Western lifestyle, have a dominant role in this increasing prevalence.
The Western way of life is accompanied by profound changes in eating habits, promoting foods high in fat, sugar and salt with excessive calorie intake, leading to an increase in obesity in the last 20 years,” he adds.
“Therefore,” continues the expert, “the relationship between Obesity and Autoimmunity has troubled the medical community and the involvement of obesity in the increase of autoimmune conditions has been strongly suggested. This association has become even more pronounced in recent years after the discovery of the remarkable properties of adipose tissue.
Indeed, white adipose tissue (WAT), long regarded as an inert energy storage tissue, has been recognized as an essential endocrine organ, secreting a wide variety of soluble mediators called adipokines or adipocytokines.
Originally identified for their metabolic activities and appetite regulation, adipokines were later found to be involved in various processes, including immunity and inflammation.
With their pro-inflammatory action, these molecules contribute to the so-called “low-grade inflammatory state” in obese individuals, resulting in the appearance of a group of co-morbidities – such as metabolic syndrome, diabetes or cardiovascular complications.
At the same time, the effect of adipokines on the appearance and worsening of many Autoimmune diseases, such as Rheumatoid Arthritis, Systemic Lupus Erythematosus, Psoriatic Arthritis, etc., was established.
Indeed, methods allowing the determination of body fat ratio (eg dual energy x-RAY absorpsiometry-DXA etc.) have shown that patients with Rheumatoid Arthritis have more body fat for a given BMI than healthy controls.
Adipose tissue in normal-weight individuals consists mainly of mature adipocytes, preadipocytes, i.e., immature adipocyte precursors, fibroblasts, endothelial cells, and immune cells.
Almost the full range of immune cells, and especially macrophages, are represented among these immune cells that reside in adipose tissue and have important functions.
The progressive and excessive accumulation of fat that occurs in obesity leads to substantial changes in the amount and phenotype of Adipose Tissue (AT) immune cells, with an increase in the number and activity of some of them (mainly macrophages, mast cells, neutrophils and T and B lymphocytes) while decreasing others, including eosinophils and several subsets of T lymphocytes [Τ βοηθητικά κύτταρα 2 (Th2), Treg, κ.ά.] .
This imbalance contributes to the development of local and systemic inflammation associated with obesity, and although most types of immune cells are already present in adipose tissue, their number increases significantly with the progression of obesity.”
in conclusion

“Obesity is a risk factor for many inflammatory and autoimmune diseases, especially rheumatoid arthritis (RA), multiple sclerosis (MS), psoriasis, psoriatic arthritis (PSA), etc., in terms of incidence, disease severity, as well as overall cardiovascular risk.
Research and knowledge in the field of obesity and its effects has been increasing continuously in recent years.
An even deeper understanding of the pathophysiological mechanisms that govern the interaction between obesity, inflammation and the pathogenic pathways of autoimmune diseases seems to be of the utmost importance for improving the treatment of patients with autoimmune rheumatic diseases,” concludes Ms. Komninou.