Prevalence of Non-alcoholic Fatty Liver Disease (NAFLD) among Children and Adolescents (<18 years) in India: A Systematic Review and Meta-analysis

The liver is a hardworking organ, a chemical factory inside the body that filters blood, stores energy, and helps digest food. Sometimes, however, this factory gets clogged with too much fat. When fat builds up in the liver of someone who does not drink alcohol, doctors call it non-alcoholic fatty liver disease. For a long time, this condition was thought to be a problem only for adults, usually linked to poor diet and a lack of exercise. But in recent years, doctors have noticed that children are increasingly developing this same condition. This shift is worrying because a liver filled with fat is not just a passive storage issue; it can become inflamed, scar, and eventually fail, leading to serious health problems later in life. The rise in this disease among young people mirrors a global increase in childhood obesity, suggesting that the way children are living and eating is changing their internal biology in profound ways.

In India, where rapid changes in lifestyle and diet are reshaping the health of the population, researchers wanted to know exactly how widespread this problem has become among children and teenagers. A team of scientists set out to gather every available study that had measured the presence of fatty liver in Indian youth under the age of eighteen. They did not conduct a new experiment themselves; instead, they acted as synthesizers, pulling together data from eleven different studies published between 2012 and 2023. These studies varied in size and location, covering children from schools, hospitals, and communities across nine specific states and union territories. The researchers carefully checked the quality of each study, ensuring they were looking at real data collected from actual children, and then combined the numbers to get a clearer picture of the national situation.

The result of this massive data gathering is a stark revelation: non-alcoholic fatty liver disease is already affecting a significant portion of Indian children. When looking at all the children included in these studies, the researchers found that roughly one in three young people has the condition. This figure is an average that masks a much deeper divide based on body weight. Among children who are of average weight and considered low-risk, the disease is present in about one out of every ten children. However, the picture changes dramatically for those who are overweight or obese. In this high-risk group, the disease is found in nearly six out of every ten children. This means that for a child carrying excess weight, the likelihood of having a fatty liver is extremely high, turning what might seem like a minor weight issue into a serious internal health crisis.

The researchers were careful to note that these numbers come with a degree of uncertainty because the studies they reviewed were not all identical. Some looked at children in specific cities, others in different regions, and they used slightly different methods to diagnose the condition, mostly relying on ultrasound scans to see the fat inside the liver. Because of these differences, the exact percentage of affected children varies from study to study, creating a wide range of possible numbers. Despite this variation, the trend is unmistakable and consistent: the burden of the disease falls heavily on those who are overweight. The data suggests that the metabolic changes leading to fatty liver are happening early in life, often before a child shows any obvious symptoms of illness.

This finding carries a heavy weight for the future of public health in India. It indicates that the problem is not just about a few isolated cases but is a growing epidemic that is taking root in the youngest generation. The researchers emphasize that because the disease is often silent in its early stages, many children are likely living with it without their parents or doctors knowing. The high prevalence among overweight children suggests that the current rise in childhood obesity is directly fueling a rise in liver disease. The study does not offer a cure, but it provides a crucial map of the problem. It shows that if the nation wants to protect the long-term health of its children, it must address the root causes of obesity and metabolic health now, rather than waiting for the liver damage to become severe. The evidence is clear that for a large number of Indian children, the path to a healthy liver begins with managing their weight and lifestyle.