A study by the South African Medical Research Council (SAMRC) and Inkosi Albert Luthuli Central Hospital (IALCH) has linked childhood obesity to an escalation in chronic health conditions previously only seen in adults – which is serious cause for alarm, say the authors.
Published in the journal Obesity Pillars, the study is the first in this country to comprehensively assess obesity-related comorbidities in children under 12, reports The Mercury.
The researchers analysed health records of 430 children treated for obesity between 2012 and 2022, with an average age of seven, and with more than a quarter (27.9%) being under five.
Professor Nasheeta Peer, from the SAMRC’s Non-Communicable Diseases Research Unit and one of the authors, said the findings were troubling.
“Seeing such a high burden of chronic diseases in children, some as young as five, is a red flag. These are conditions we typically expect in middle-aged adults, yet they’re already taking root in childhood due to obesity,” she said.
The study found 46.1% of the children had hypertension, while 12.8% were pre-hypertensive. In addition, 30.2% had dyslipidaemia, or abnormal cholesterol or fat levels in the blood, and about 5% had either prediabetes or type 2 diabetes. These conditions, researchers warn, significantly raise the risk of cardiovascular diseases and kidney problems later in life.
Peer stressed the urgent need to intervene early. “The data show a clear link between lifestyle and these health conditions. We must intervene early if we want to reverse the trend,” she said.
Many of the children reported behaviours that contribute to weight gain and cardiometabolic issues. Nearly half (47.9%) consumed sugary soft drinks daily, 43.5% spent more than two hours a day on screens, and 42.3% engaged in less than 30 minutes of physical activity per day.
Researchers also noted a strong family history of obesity, diabetes, and hypertension, suggesting a combination of genetic predisposition and shared unhealthy environments.
The study urged immediate interventions focused on prevention, including promoting healthy diets, increasing physical activity, and reducing screen time among children. It also recommends routine screening to detect obesity-related conditions early.
“The earlier we act, the better,” said Peer. “Children with high glucose or high blood pressure levels still have a chance to reverse these conditions. But without action, we’re looking at a generation facing high rates of heart disease and diabetes by the time they reach adulthood.”
Study details
Comorbidities of childhood obesity at a tertiary hospital in KwaZulu-Natal
Nasheeta Peer, Janice Sewlall, Yusentha Balakrishna, Shafeeka Tayob, Andre-Pascal Kengne, Yasmeen Ganie.
Published in Obesity Pillars in September 2025
Abstract
Aim
To describe the distribution of childhood obesity and their related comorbidities in <12-year-old children assessed at a South African tertiary hospital from 2012 to 2022.
Methods
In this retrospective electronic chart review, data extracted comprised socio-demographic and lifestyle histories, physical examination and biochemical analyses. World Health Organisation child growth reference defined obesity as z-score ≥2 standard deviations (SD) for 5-19-year-olds, and z-score ≥3 SD for <5-year-olds. Systolic blood pressure and/or diastolic blood pressure ≥95th percentile and 90–94th percentile for age, gender and height, defined hypertension and prehypertension, respectively. Type 2 diabetes and prediabetes diagnoses were based on oral glucose tolerance tests or random blood glucose levels. Dyslipidaemia was deemed present with any abnormality of total cholesterol, low-density lipoprotein cholesterol, high-density lipoprotein cholesterol or triglycerides.
Results
Among 430 participants, 52.1 % (n = 224) male, 27.9 % (n = 120) ≤5-years-old and 64.7 % black African, unhealthy lifestyle behaviours were prevalent: 42.3 % spent <30 min/day on physical activity, 43.5 % spent >2 h/day on screen time and 47.9 % consumed soft drinks daily. Family history of obesity (41.9 %), diabetes (40.5 %) and hypertension (40.0 %) was common. Among participants, hypertension (46.1 %) and prehypertension (12.8 %) were high. Type 2 diabetes was low at 1.6 % but prediabetes was 3.3 %. Any dyslipidaemia was prevalent at 30.2 %.
Conclusions
The high burden of cardiometabolic comorbidities in children with obesity warrants concerted interventions at young ages to prevent worsening of comorbidities and the reversal of prehypertension and prediabetes. Unhealthy dietary habits, low activity levels and sedentary behaviours in children need to be urgently targeted to reduce obesity and its comorbidities.
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