Lancet study links obesity to 1 in 10 infection deaths globally. What it means for India

A growing body of evidence suggests a significant link between obesity and increased risk from infectious diseases. Recent research, spurred by observations during the COVID-19 pandemic, indicates that individuals with obesity may face a substantially higher chance of severe illness or death when infected with a range of pathogens.

Unpacking the Connection

Researchers sought to determine if the increased risk observed during the COVID-19 pandemic extended to infectious diseases more broadly. The study analyzed data from over 67,000 adults in Finland and more than 470,000 adults participating in the UK Biobank, tracking hospital admissions and deaths related to infection over a 13- to 14-year period.

Widespread Vulnerability

The findings revealed that obesity heightened the risk of severe outcomes from infections like influenza, COVID-19, pneumonia, gastroenteritis, urinary tract infections, and lower respiratory tract infections. Notably, the study did not find a correlation between obesity and severe outcomes from HIV or tuberculosis.

Did You Know? In the UK Biobank group, people with a healthy BMI had a 1.1 percent chance each year of experiencing a severe infection, while those with obesity faced an 1.8 percent annual risk.

The risk of severe infection increased alongside body weight. Globally, researchers using data from the Global Burden of Diseases (GBD) Study estimated that obesity may have been linked to approximately 0.6 million out of 5.4 million infectious disease deaths in 2023 – roughly one in ten deaths.

Global Impact and Regional Variations

The impact of obesity on infection-related deaths varied significantly by country. In the United States, obesity was linked to about one in four infection-related deaths. The United Kingdom saw a link to approximately one in six deaths, while Vietnam reported a much lower proportion, around one percent.

A Growing Trend

Dr. Solja Nyberg of the University of Helsinki in Finland noted that, “Our findings suggest that people living with obesity are significantly more likely to become severely ill or to die from a wide range of infectious diseases. As obesity rates are expected to rise globally, so will the number of deaths and hospitalisations from infectious diseases linked to obesity.”

Expert Insight: The findings underscore the potential for a cascading effect: rising obesity rates could translate directly into increased strain on healthcare systems due to a surge in severe infectious disease cases.

UNICEF’s Child Nutrition Global Report 2025 indicates a concerning shift in malnutrition trends, with obesity now surpassing underweight as the most prevalent form of malnutrition among school-aged children and adolescents worldwide. Approximately one in ten children globally—around 188 million—are currently living with obesity.

Specific Vulnerabilities

Dr. Anoop Misra, chairperson of Fortis C-DOC Hospital for Diabetes and Allied Sciences in New Delhi, highlighted the particular relevance of these findings for India, where the burden of infection remains high. He explained that individuals in India often develop diabetes and metabolic dysfunction at lower levels of obesity, further compromising their immune systems.

Dr. Atul Kakar, chairperson of Internal Medicine at Sir Ganga Ram Hospital, added that obesity is associated with low-grade inflammation and impaired immunity throughout the gut, skin, and respiratory system, thereby increasing susceptibility to infection.

Looking Ahead

further research will refine our understanding of the specific mechanisms linking obesity and increased infection risk. Analysts expect that continued monitoring of obesity rates and infectious disease outcomes will be crucial for public health planning. A possible next step could involve targeted interventions aimed at addressing obesity and bolstering immune function in vulnerable populations.

Frequently Asked Questions

What infections were specifically linked to increased risk in obese individuals?

The study found that obesity raised the risk of severe illness or death from flu, COVID-19, pneumonia, gastroenteritis, urinary tract infections and lower respiratory tract infections.

Did the study find a link between obesity and all infectious diseases?

No, the authors noted that obesity did not appear to increase the risk of severe HIV or tuberculosis.

Is this study definitive proof that obesity causes more severe infections?

The authors cautioned that the analysis was based on observational data and therefore cannot establish a cause-and-effect relationship.

Given these findings, how might public health strategies need to evolve to address the growing intersection of obesity and infectious disease vulnerability?