Obesity and low-grade inflammation: a paediatric perspective

Childhood obesity is a major public health problem. Low-grade inflammation, a hallmark characterizing adult obesity, may be a pivotal mechanism linking obesity to its numerous systemic complications, with adipose tissue depots secreting and producing inflammatory mediators and visceral fat displaying an increased inflammatory profile. While knowledge is relatively scarce regarding the importance of the adipose tissue inflammation process in children, identifying its contribution in childhood obesity and the associated influences of age, sex, weight status, growth, and adipose depot phenotypes are crucial for understanding physiopathology and implementing early intervention strategies. We review the latest research linking obesity and inflammation in childhood focusing on serum inflammatory markers and the effectiveness of lifestyle interventions in improving systemic inflammation. Generally, there are significant correlations between body mass index and increased c-reactive protein and decreased adiponectin levels in children; these levels tend to be improved in interventions resulting in similar to 5% weight loss, regardless of the type or length of intervention. There is a need for further research measuring other inflammatory mediators (e.g. tumour necrosis factor (TNF)-alpha, IL-6, IL-8) and histological studies examining immune cell infiltration in adipose tissue depots in obese children.