A study conducted by researchers from the Federal University of São Paulo (Unifesp) with 130 children between 6 and 11 years old identified that obesity can cause, in itself, immediate damage to children’s cardiovascular health, increasing the risk of diseases such as atherosclerosis, heart attack and stroke in childhood.
The work, supported by Fapesp, identified early signs of inflammation and dysfunction in the endothelium – the layer that lines the blood vessels – in overweight and obese children.
“The results of the study reinforce the severity of childhood obesity, showing that it needs to be reversed from an early age. We also warn about the need for public policies to reduce obesity in childhood, especially in populations in socioeconomic vulnerability”, says Maria do Carmo Pinho Franco, professor at Unifesp and author of the study at International Journal of Obesity.
The researcher explains that obesity promotes – in adults and children – chronic, low-grade inflammation that leaves the body’s defense system on constant alert, generating a succession of false alarms and, consequently, premature aging of immune cells. In the endothelium, the focus of the study, the researchers identified that this inflammatory process causes cellular damage, even in children, which increases the severity of childhood obesity.
“It was already known that overweight or obese children tend to become teenagers and adults with the same problem, which increases the risk of developing cardiovascular and cardiometabolic diseases in the future. But this effect is not just cumulative. The study identified that overweight or obese children already show signs of inflammation and endothelial dysfunction, indicating that the process of cardiovascular disease begins in childhood, even before other risk factors appear”, says Franco.
“These children do not smoke, do not drink and do not have decades of bad habits considered risk factors for cardiovascular diseases. This is also a pre-pubertal population, that is, without the influence of sexual hormones. The only factor present is excess weight. Therefore, the analysis showed that obesity, in itself, is sufficient to initiate a low-grade chronic inflammatory process, with a direct impact on vascular health”, he adds.
In the work, the researchers found an increase in gene expression of the inflammatory cytokine TNF-alpha in blood samples from overweight or obese children, in addition to an increase in circulating levels of apoptotic endothelial microparticles (EMPs) – both inflammatory markers may indicate damage to the endothelial cell, contributing to tissue dysfunction. Franco explains that, as the endothelium is considered the orchestrator of vascular health, early damage to blood vessels detected when examining children can lead to diseases such as atherosclerosis, heart attack and stroke ().
The research also measured indicators such as body mass index (), waist circumference, blood pressure and endothelial function of the microvasculature. Overweight and obese children performed worse on the Reactive Hyperemia Index (RHI), which assesses the health of microvessels, in addition to greater expression of the TNF-alpha gene, a factor that correlated with high levels of EMPs and worsening endothelial function.
Another important aspect of the study is that it was conducted with children attended at a Youth Center in the capital of São Paulo. The assessment of BMI, waist circumference, blood pressure and peripheral arterial tonometry was carried out on site, with the support of volunteer nutritionists, doctors and nurses.
Laboratory analyses, including RNA extraction and quantification of inflammatory markers by PCR (qRT-PCR), were carried out at the Department of Biophysics at Escola Paulista de Medicina (EPM-Unifesp).
Awareness raising and training work was also carried out with lunch ladies and guardians in which they were taught recipes that would replace the use of on the children’s menu, prioritizing healthy foods.
The researchers defend the urgent need to expand and strengthen public policies to prevent childhood obesity, especially in communities with socioeconomic vulnerability. “In addition to the individual problem, without early intervention these children tend to become adults with cardiovascular and metabolic diseases, which represents a worrying impact on public health and the sustainability of the Brazilian health system”, warns Franco.
