Growing Obesity Burden Driving Up Indian's 'Cardiac Age', Warn Doctors

Your heart may be older than you think, say doctors, warning that as obesity rates rise in India, many people may have a 'cardiac age' significantly older than their actual age, raising the risk of cardiovascular disease much earlier than expected.

The concern comes in the wake of findings from the National Family Health Survey-6 (NFHS-6), which showed a sharp increase in obesity among Indian adults.

The survey found that 30.7 per cent of women aged 15-49 years were overweight or obese in 2023-24, up from 24 per cent in NFHS-5 (2019-21), while the proportion among men rose from 22.9 per cent to 27.3 per cent.

Experts said the trend, coupled with rising diabetes and hypertension, could translate into a greater burden of heart disease.

Dr Nitish Naik, Professor of Cardiology at AIIMS, Delhi, said cardiac age is increasingly being used to explain cardiovascular risk in a way people can easily understand.

Speaking to PTI, Dr Naik said, "Cardiac age is not necessarily the same as a person's chronological age. It is an assessment of how healthy or unhealthy the cardiovascular system is based on various risk factors." A 35-year-old with obesity, diabetes, high blood pressure and a sedentary lifestyle may well have a cardiovascular risk profile similar to that of a much older person, he said.

According to the World Health Organization, overweight and obesity are among the leading risk factors for non-communicable diseases, including heart disease and stroke, which remain leading causes of death globally.

Dr Rahul Chandola, Chairman of the Institute of Heart, Lungs Diseases Research Centre and founder of an AI-based healthcare technology platform iLive Connect, said obesity is the major determinant of cardiovascular health and it is a major problem across the world, including India.

He said the sedentary lifestyle, sitting for long hours in offices, consumption of unhealthy foods, and stress contribute to obesity.

Explaining cardiac age, Dr Chandola, a cardiovascular surgeon, said it is a measure of the biological health of the heart and blood vessels, reflecting the organ's physiological condition rather than the number of years a person has lived.

He said a person aged 70 or 80 may have a much younger heart if the overall cardiovascular condition is good. Similarly, a younger person can have an older cardiac age if multiple risk factors are present.

Cardiac age is determined by factors such as blood pressure, heart rate, ECG findings, heart-rate variability, blood sugar control, exercise levels and overall cardiovascular fitness, he added.

The advances in technology and AI are making it possible to precisely estimate cardiac age, he said, adding that "Platforms such as iLive can analyse multiple physiological parameters and estimate one's cardiac age." According to Dr Chandola, the platform, incorporating multiple variables, including data collected via sensors and a wristband, tracks physiological parameters in real time over a period of time. This information is analysed using AI to generate a person's cardiac age.

Dr Naik said many Indians remain unaware that cardiovascular damage often begins years before symptoms appear.

"People frequently focus only on body weight, but metabolic health is equally important. Obesity can silently damage blood vessels, increase insulin resistance and raise blood pressure. By the time symptoms develop, significant cardiovascular damage may already have occurred," he said.

Doctors say obesity accelerates cardiac ageing through several biological mechanisms.

Dr H S Isser, Head of Department of Cardiology at VMMC and Safdarjung Hospital, said that excess body fat, particularly around the abdomen, triggers chronic inflammation, increases blood pressure, worsens cholesterol levels and promotes insulin resistance, all of which damage blood vessels and force the heart to work harder.

He said obesity rarely occurs in isolation.

"Obesity is closely linked with a cluster of metabolic disorders, including diabetes, hypertension and abnormal lipid levels. Together, these conditions significantly increase the risk of coronary artery disease, heart failure and stroke. The rise in obesity reflected in NFHS-6 is therefore a serious public-health concern," he said.

Dr Isser said abdominal obesity is particularly dangerous because it surrounds vital organs and drives metabolic dysfunction.

"Many people focus only on body weight, but waist circumference and visceral fat are equally important. A person may not appear significantly overweight yet still be carrying excess abdominal fat that increases cardiovascular risk. This is one reason why Indians are seeing heart disease at relatively younger ages," he elaborated.

Dr Anil Gurtoo, Head of Dept of Medicine at Sitaram Bhartia Institute of Science and Research said, "While the Calendar displays one age, the heart may reveal another age. So, while we may be 40 years old by the calendar, our heart may have crossed 60 years." This unsettling paradox of the young-old and the thin-fat is becoming all too common, as the silent epidemic of visceral obesity sweeps across South Asia, he said.

"What makes this phenomenon unique is that, unlike the Western populations, obesity in the Indian population expresses very differently -- by developing early-onset cardio-metabolic disease at lower body weights leading to early diabetes and heart attacks at ages as young as thirty," Dr Gurtoo said.

Overall, the outward thin body profile often hides the inward deposits of thick visceral fat wrapped around internal organs like liver, pancreas, and blood vessels.

Unlike the fat under the skin, this layer of fat around organs behaves like a giant endocrine organ constantly churning out signals of inflammation and insulin resistance that slowly damage and harden the blood vessels, heart and pancreas, leading to early heart attacks and diabetes.

"However, the good news is that this paradox is entirely preventable, even reversible through a combination of physical exercise, healthy eating, particularly avoidance of ultra-processed foods and carbonated drinks, and 7-8 hours of sleep.

"The encouraging message is that heart age can be improved through weight control, regular physical activity, a healthy diet, smoking cessation, and timely management of risk factors. Preventing obesity today is an investment in a younger and healthier heart tomorrow," Dr Isser added.