Is your ‘healthy’ child at risk of heart diseases and diabetes?

When it comes to children’s health, appearances are anything but deceptive.A new, large-scale study conducted by the All India Institute of Medical Sciences (AIIMS) and funded by the Indian Council of Medical Research (ICMR) reveals that many Delhi schoolchildren — whether overweight, underweight or seemingly ‘normal’ — are showing subtle signs of future heart disease, diabetes, and metabolic dysfunction.Published in PLOS One in May, the study tracked 3,888 students aged six to 19 years from five Delhi schools and found startling inequalities in how socioeconomic status, school type, nutrition, and lifestyle impact metabolic health. The most startling find of the study is that obesity is more than five times higher in private schools than in public ones. But beneath that figure lies a deeper, more complicated health emergency.The study is also a first-of-its-kind. Its research is part of a broader initiative called LEAP-C (short for Longitudinal Evaluation of Anthro-metabolic Parameters in Children). A longitudinal study means researchers follow the same individuals over an extended period tracking how their health parameters change. Unlike a one-off survey, longitudinal research allows one to understand how childhood traits evolve, and which ones predict future disease.What also sets this study apart from others is its timing and scope. Conducted in the aftermath of the Covid pandemic, LEAP-C is one of the first Indian studies to provide a post-pandemic baseline of children’s metabolic health. During the pandemic, children experienced prolonged school closures, reduced physical activity, increased screen time, psychological stress, and major shifts in diet, especially in urban India. This unique time frame, when habits were disrupted across all economic classes, makes the findings not just timely, but urgent.How the study was conductedThe children were recruited from three public (non-fee-paying) and two private (fee-paying) schools — chosen to represent lower and higher socioeconomic groups.The research team took multiple body measurements (called anthropometry), blood pressure readings, and fasting blood samples from adolescents to measure cholesterol, triglycerides (a type of fat that circulates in the blood and are the most common type of fat in the body), glucose, insulin, and more.They did so to identify early signs of “cardio-metabolic” risk — that is, a combination of factors that raise the chances of developing heart disease, diabetes, or related chronic illnesses later in life. What the study foundThe data was able to confirm that obesity is actually associated with wealth. According to Indian Academy of Pediatrics (IAP) criteria — which is considered more appropriate for Indian children than WHO (World Health Organisation) or IOTF (International Obesity Task Force) guidelines — nearly 23% of private school students were obese, compared to just 4.5% in public schools.Central obesity, which refers to excess fat around the waist and is particularly dangerous for heart health, was eight times more prevalent in private schools (16.8% vs 1.8%).But the real shocking find is that being thin or normal weight did not mean being healthy. Here, the study identifies two important groups:Metabolically Obese Normal Weight (MONW): These children appear normal by BMI but show internal metabolic disturbances.Metabolically Obese Underweight (MOUW): These children are underweight but still carry risk markers for disease.Among children with normal BMI, 42.9% had at least one metabolic abnormality like low HDL (‘good’) cholesterol, high triglycerides, or impaired fasting glucose. This proportion was even higher in public schools (46.4%) compared to private schools (35.3%).Among underweight children, 41.7% had at least one abnormality, proving that malnutrition and metabolic risk often coexist.Also striking is the prevalence of metabolic syndrome — a cluster of risk factors that includes abdominal obesity, high blood pressure, low HDL cholesterol, high triglycerides, and high blood sugar. It was found in 5.76% of private school adolescents, and 1.75% of public school adolescents, meaning students from wealthier schools were over three times more likely to meet the clinical definition of metabolic syndrome.Similarly, impaired fasting glucose, a possible sign of prediabetes, was present in one in five adolescents in private schools (20.74%) versus around one in 10 in public schools (10.93%).These findings take on additional weight in the post-Covid world, where schoolchildren — especially in urban centres — emerged from lockdown with sedentary habits and disrupted meal patterns. The LEAP-C study gives us a much-needed, evidence-backed snapshot of just how serious the consequences have been.How were children assessed? The team used three internationally recognised systems to classify weight: the WHO system, the IOTF system, and the IAP system. The IAP system was found most suitable, as it accounts for differences in Indian children’s body composition.Anthropometric data included height, weight, waist and hip circumference, and mid-upper arm circumference. Blood pressure was measured using an automatic device. Fasting blood samples, collected only from adolescents aged 10 to 19, were tested for:Total cholesterol: A type of fat in the blood that, when elevated, increases heart risk.HDL (High-Density Lipoprotein): Often called ‘good’ cholesterol; low levels are a concern.LDL (Low-Density Lipoprotein): The ‘bad’ cholesterol.Triglycerides: High levels increase disease risk.Fasting glucose: High levels suggest risk of diabetes.Insulin: High levels can indicate insulin resistance.HOMA-IR: A calculated measure used to assess insulin resistance.The study also evaluated metabolic syndrome using the International Diabetes Federation (IDF) definition, applicable to children aged 10 years or older. This includes abdominal obesity plus at least two of the following: high triglycerides, low HDL, high blood pressure, or elevated fasting glucose.The most common abnormality found was low HDL cholesterol, especially among public school students with normal or low weight.One-third of adolescents (33.7%) had dyslipidemia, which means some form of abnormal cholesterol or fat levels in the blood. Surprisingly, this was slightly more common in public schoolgirls than their private school peers. So, who is most at risk?Boys were generally at greater risk. In private schools, nearly 29% of boys aged 6-9 were obese, compared to 17% of girls. Boys were also more likely to have impaired fasting glucose and high triglycerides. This may be due to more sedentary leisure activities like video gaming, whereas girls, especially from poorer households, tend to be physically more active through household chores.Also, metabolic syndrome and MONW phenotypes were more common in older adolescents aged 15-19, highlighting how risk builds over time.What this means for usThe researchers recommend universal screening for metabolic disorders in schools, not just for overweight children but for everyone. They also call for better nutrition, increased physical activity, and reduced screen time, especially in private schools where obesity is rampant.For public schools, the challenge is different: improving basic food quality and ensuring children aren’t just fed but nourished. The researchers also urge policymakers to not equate thinness with wellness.It’s worth noting that many of the children in the study came from homes where parents, especially mothers in public schools, had limited formal education. For instance, over one-third of public school mothers had no schooling at all. That kind of background can affect everything from diet to physical activity to healthcare access.The study also highlights that India is in the midst of a nutritional transition. While parts of the population still struggle with undernutrition, others are facing an epidemic of lifestyle disease. And sometimes, the same children are affected by both.This means that cardio-metabolic risk is no longer a problem of the future. We are now looking at a generation with invisible illness, one that needs early detection, better habits, and urgent attention from policymakers, educators, and parents alike.