**5. Perspectives**

At present, it seeks to make the value of clinical information available further effective, favouring a comprehensive approach to identify novel early biomarkers in the development of obesity and its co-morbidities.

In obesity, the biologic representative hallmark is the establishment of a subclinical chronic low-grade inflammatory process, promoted by the dysregulation of the immune system cells resident of white adipose tissue. Antagonistically, an underlying molecular mechanism induced by BAT control (hypermetabolism) can be developed. The understanding of both processes may allow the identification of early biomarkers with therapeutic aim of mitigate or eliminate the associated immunometabolic effects.

Researchers have focused their efforts on finding new biomarkers in obesity, based on the concept that a biomarker is identified as a qualitatively and/or quantitatively measurable biological parameter, which can be characterized as an indicator of health status versus disease, and also it serves as a marker for susceptibility or to stratify the relative risk in the general population.

The importance of a novel early biomarker is that it can have a high diagnostic or prognostic value in the context of development, establishment and progression of obesity and its comorbidities. Because cut-off values are established in the biomarker validation process, it can be identified as a 'distorted indicator and differentiated predecessor' of clinical manifestations, with the possibility of aid at establishment, a classification in the progression of co-morbidities and severity of obesity.

As a consequence, from discovery to clinical application, an ideal early biomarker need run into the following characteristic: be easily accessible by using a sampling procedure minimally invasive, therefore, samples of blood, urine and saliva are excellent sources of choice.

In this contextual group of ideas, miRNAs that are transported to target cells through the bloodstream, are relatively stable and easily removed from blood serum have been identified. They are associated with metabolic risk and dysregulation of the immune system when white adipose tissue increases, and they are postulated as candidates of 'novel early biomarkers', due to their ability to become acquainted with the progression of the pathogenic process of obesity.
