Thirty-one year old Sunil (name changed), who weighed 186 kg and worked as a dealer for dental equipment in Mumbai, was hospitalised twice last year, in August and December, for severe respiratory infection. Each episode was marked by worsening breathlessness and dangerously low oxygen levels. Sunil required intensive care during both admissions including oxygen therapy and non-invasive ventilatory support (BiPAP) despite not having any major chronic illness typically associated with such severe infections at a young age.
His problems stemmed from his body weight, classified as class III obesity. This significantly increases the risk of comorbidities, including Type 2 diabetes, high blood pressure, stroke, heart disease, osteoarthritis and reduced breathing function. “Obesity compromised his lung function, reduced his respiratory reserve (extra breathing capacity) and although he recovered with treatment on both occasions, the recurrence of severe infection requiring frequent hospitalisation highlights an important but under-recognised risk of obesity,” says Dr Aparna Govil Bhasker, laparoscopic and bariatric surgeon.
Excess body fat is known to impair immune responses, promote chronic inflammation and restrict lung expansion making infections more frequent, severe and slower to resolve, she explains. Her observations are in tune with findings of a new study that suggests people with obesity are 70 per cent more likely to be hospitalised or die from an infectious disease. People with the most severe obesity face three times the risk. Obesity significantly increased the risk of hospitalisation and death from most infectious diseases, including flu, Covid-19, pneumonia, gastroenteritis, urinary tract and respiratory tract infections as per the new study of 5.4 lakh people.
When these findings are extrapolated globally, they suggest that obesity may have been a driving factor in 0.6 million out of 5.4 million deaths (10.8%) from infectious diseases in 2023.
Link between obesity and infections
Obesity as a trigger for infections in India
In India, one in 26 deaths from infectious diseases was linked with obesity in 2023 as per the latest estimates from the Global Burden of Diseases (GBD). The corresponding figures were one in four in the US, and one in 11 in China as per a new report in The Lancet.
Study authors used infectious disease mortality data from the GBD study to model the impact of obesity on infectious diseases deaths for different countries. While study authors highlight that estimates of the global impact should be interpreted with caution, they also warn that given rising global obesity rates, the number of serious infections linked to obesity is likely to grow in the coming decades.
Prof Mika Kivimaki, Director, Whitehall II study, UCL Brain Sciences, University College London and lead author, says their study shows why it matters to ensure better weight management that appears to reduce health risk. “Another practical takeaway is that people with obesity should treat infections carefully and ensure their vaccinations are up to date,” Prof Mika says.
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Role of obesity as a risk factor
Dr Bhasker finds the data significant enough to outline the role of obesity as a risk factor for both communicable and non-communicable diseases. “In a country like India, where the burden of infectious diseases is already very high, the parallel rise in obesity adds an additional and often underestimated layer of disease burden, placing further strain on the healthcare system,” she says. She also points out that the susceptibility to infectious disease in patients with obesity could be due to impairment of innate and adaptive immune responses and Vitamin D deficiency.
“As per data in 2019 alone, 5.7 lakh adult deaths were attributed to overweight or obesity, primarily due to type 2 diabetes, cardiovascular disease, stroke and cancer. The infectious disease burden further adds to the already substantial impact of obesity on NCDs in India,” Dr Bhasker explains.
A broad-based study
The study used data from 67,000 adults in two studies in Finland. Over 4.7 lakh adults in the UK Biobank dataset were also included to look at the relationship between obesity and severe infectious disease. The body mass index (BMI) of subjects was assessed when they entered the studies and were followed up for an average of 13-14 years. Those with obesity defined as BMI more than 30 kg/m2 had a 70% higher risk of hospitalisation or death from any infectious disease compared to people with a BMI between 18.5 to 24.9. Authors also said that the study relied on observational data and cannot confirm the causality of the associations.
Anuradha Mascarenhas is a Senior Editor at The Indian Express, based in Pune. With a career spanning three decades, she is one of the most respected voices in Indian journalism regarding healthcare, science and environment and research developments. She also takes a keen interest in covering women's issues .
Professional Background
Education: A gold medalist in Communication and Journalism from Savitribai Phule Pune University and a Master’s degree in Literature.
Author: She authored the biography At The Wheel Of Research, which chronicles the life and work of Dr. Soumya Swaminathan, the former Chief Scientist at the WHO.
Key Focus: She combines scientific accuracy with storytelling, translating complex medical research into compelling public and human-interest narratives.
Awards and Recognition
Anuradha has won several awards including the Press Council of India's national award for excellence in journalism under the gender based reporting category in 2019 and the Laadli Media award (gender sensitivity -2024). A recipient of the Lokmat journalism award (gender category-2022), she was also shortlisted for the RedInk awards for excellence in journalism-2021. Her debut book At The Wheel Of Research, an exclusive biography of Dr Soumya Swaminathan the inaugural chief scientist of World Health Organisation was also nominated in the Popular Choice Category of JK Paper AUTHER awards. She has also secured competitive fellowships including the Laadli Media Fellowship (2022), the Survivors Against TB – New Research in TB Media Fellowship (2023) and is part of the prestigious 2025 India Cohort of the WomenLift Health Leadership Journey.”
Recent Notable Articles (Late 2025)
1. Cancer & Specialized Medical Care
"Tata Memorial finds way to kill drug-resistant cancer cells" (Nov 26, 2025): Reporting on a breakthrough for triple-negative breast cancer, one of the most aggressive forms of the disease.
Discipline, diet and purpose; How a 97-year-old professor defies ageing'' (Nov 15, 2025) Report about Prof Gururaj Mutalik, the first Head of Department at Pune's B J Government Medical College who at 97 credits his longevity to healthy habits and a strong sense of purpose.
2. Environmental Health (The "Breathless Pune" Series)
Long-term exposure even to 'moderate' air leads to chronic heart, lung, kidney issues" (Nov 26, 2025): Part of an investigative series highlighting that even "safe" pollution levels are damaging to vital organs.
"For every 10 µg/m3 increase in PM2.5 level, there was 6-8% jump in medicine sales" (Nov 23, 2025): Using commercial data to prove the direct link between air quality and respiratory illnesses in Pune.
3. Lifestyle & Wellness News
"They didn't let cancer, diabetes and heart disease stop them from travelling" (Dec 22, 2025): A collaborative piece featuring survivors who share practical tips for traveling with chronic conditions.
At 17, his BP shot up to 200/120 mmHG; Lancet study flags why child and teen hypertension doubled between 2000 and 2020'' (Nov 12,2025)--A report that focusses on 17-year-old-boy's hypertensive crisis and reflects the rising global trend of high blood pressure among children and adolescents.
4. Scientific Recognition & Infrastructure
For promoting sci-comm, gender diversity: IUCAA woman prof highlighted in Nature" (Nov 25, 2025): Covering the global recognition of Indian women scientists in gender studies and physics.
Pune researchers find a spiral galaxy like the Milky Way from early universe'' (December 3, 2025)- A report on how Indian researchers discovered a massive galaxy that existed when the universe was just 1.5 billion years old , one of the earliest to have been observed so far.
Signature Beat: Health, Science & Women in Leadership
Anuradha is known for her COVID-19 reportage, where she was one of the first journalists to provide detailed insights into the Covishield and Covaxin trials. She has a dedicated interest in gender diversity in health and science, often profiling women researchers who are breaking the "leaky pipeline" in STEM fields. Her writing style is scrupulous, often featuring interviews with top-tier scientists and health experts from various institutions.
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Link between obesity and infections
