Obesity’s Link to Infectious Diseases
Research indicates that individuals with obesity are 70% more likely to experience hospitalization or fatality due to infections, with about 10% of global deaths related to infections tied to this condition.
Being overweight or obese raises the risk significantly for severe illness and death from various infectious diseases, including flu, pneumonia, gastroenteritis, urinary tract infections, and Covid-19. This finding comes from a study involving over 500,000 people.
According to researchers, obesity may contribute to around 600,000 of the 5.4 million annual deaths (about 11%) attributed to infectious diseases.
Dr. Solja Nyberg from the University of Helsinki, who led the study, warned that the situation might worsen. She pointed out, “As obesity rates are predicted to increase globally, so will the number of deaths and hospitalizations associated with infectious diseases linked to obesity.”
She stressed the importance of implementing policies aimed at promoting healthier lifestyles and supporting weight loss, such as ensuring access to affordable nutritious food and opportunities for exercise.
In addition, Dr. Nyberg mentioned that it’s crucial for those with obesity to stay updated on vaccinations, especially considering the heightened risk of hospitalization or death from Covid-19 that was observed during the pandemic. However, there hadn’t been much evidence before this study to indicate a similar connection between obesity and other infectious diseases.
To address this knowledge gap, researchers analyzed data from 67,000 adults in Finland and 470,000 from the UK Biobank, focusing on the correlation between obesity and severe infectious illness. Participants had their body mass index (BMI) measured and were followed for about 13 to 14 years, starting at an average age of 42 in the Finnish group and 57 in the UK cohort.
The findings, published in the Lancet, determined that those with a BMI of 30 or higher (classified as obese) faced a 70% greater risk of hospitalization or death from any infectious disease compared to individuals with a BMI within the healthy range of 18.5 to 24.9. The risk further escalated as weight increased.
Prof. Mika Kivimäki of UCL, the study’s lead author, remarked, “Our finding that obesity increases the risk for numerous infectious diseases suggests that there may be broad biological mechanisms at play.”
He proposed that obesity could impair the immune system’s ability to fight off infectious agents, leading to more severe illnesses. This aligns with emerging evidence from trials involving GLP-1 weight-loss medications, which indicate that reducing obesity also lowers the risk of severe infections and offers numerous other health benefits. However, he noted that more research is needed to better understand these connections.
There were variations in the impact across different countries: roughly one in six infection-related deaths in the UK were associated with obesity, while in the US, it was one in four. In contrast, Vietnam reported the lowest association, with only 1.2% of infection deaths linked to obesity.
While the study was funded by several organizations, including Wellcome and the Medical Research Council, it faced some limitations. It mainly relied on observational data, which cannot definitively prove causality.
Dr. Sara Ahmadi-Abhari from Imperial College London, a co-author of the study, cautioned that while the global estimates shed light on the potential scale of the issue, they should be approached with care.
