Obesity contributes to more than ten percent of infectious disease deaths globally, according to new research from University College London. The findings, published in The Lancet, show that people with obesity face a seventy percent higher risk of severe illness.
Researchers examined nearly one thousand different bacterial, viral, and fungal diseases to understand the impact of high body mass index. Consequently, this study provides robust evidence that excess weight significantly worsens the outcomes of many common and rare infections.
A Vulnerable Immune System
Professor Mika Kivimaki explains that obesity acts as a well-known risk factor for metabolic syndrome, diabetes, and cardiovascular diseases. However, this new research highlights that becoming very ill from an infection is markedly more common among people with obesity.
The study indicates that individuals with a BMI of forty or higher face three times the severe infection risk. Therefore, recovery from illness becomes much harder because the body’s natural defences are often weakened by chronic systemic inflammation.
The Scale of the Research
The research team analysed data from five hundred and forty thousand participants across large-scale cohort studies in Finland and the UK. Participants had their body mass index assessed at the beginning and were then followed for an average of fourteen years.
The link between obesity and severe infections remained consistent regardless of whether scientists measured BMI or a person’s waist circumference. Furthermore, the higher the weight of the individual, the greater the statistical risk of hospitalisation for an infectious disease.
Beyond Metabolic Syndrome
Interestingly, the association between obesity and severe infection was not explained by other lifestyle factors or existing chronic conditions. The link remained consistent even for people with obesity who did not have heart disease, diabetes, or metabolic syndrome.
This suggests that obesity itself contributes to a general impairment of immune function and various related metabolic disturbances. While people may not get infected more easily, their ability to recover from a serious illness is clearly hindered.
The Benefits of Weight Loss
The researchers found promising evidence that losing weight can significantly reduce the risk of facing these severe infectious diseases. Specifically, people with obesity who lost weight had a twenty percent lower risk than those who remained obese.
As global obesity rates continue to rise, experts expect a corresponding increase in hospitalisations and deaths from infectious diseases. Consequently, public health initiatives focusing on weight management could play a vital role in protecting populations from future outbreaks.
Q&A: Understanding the Risks of Obesity
Q: Does obesity make you more likely to catch a cold or flu?
A: The study suggests you may not get infected more easily, but you are much more likely to become severely ill.
Q: Which infectious diseases are most affected by obesity?
A: Obesity increases the risk for flu, Covid-19, pneumonia, and urinary tract infections, though it does not affect HIV or tuberculosis.
Q: Is BMI the only way to measure this health risk?
A: No, the link was consistent whether researchers used body mass index, waist circumference, or the waist-to-height ratio for participants.
FAQ
What was the main finding of the UCL study?
The study found that obesity is responsible for just over ten percent of infectious disease deaths on a global scale.
How much does obesity increase the risk of hospitalisation?
Individuals with obesity have a seventy percent higher risk of hospitalisation or death from an infection than healthy weight peers.
Can losing weight help my immune system?
Yes, the study showed that losing weight reduced the risk of severe infection by approximately twenty percent for obese individuals.
Did the study look at Covid-19?
Yes, Covid-19 was one of the ten common infectious diseases that researchers examined in great detail during the study.
