Scientists have said the food industry “shares the blame” for the coronavirus crisis.
Early research suggests four out of five cases are mild, however, obesity was identified early in the outbreak as a risk factor for the respiratory disease COVID-19.
With the UK death toll exceeding 40,000, a team from Queen Mary University of London have argued the food industry contributed to the fatalities by expanding our waistlines.
‘Food industry shares the blame for the severity of COVID-19’
The “majority” of adults in England have a dangerously high body mass index (BMI), with 67% of men and 60% of women either obese or overweight.
A UK study of 340 patients admitted to hospital with the coronavirus found being overweight increased the risk by 44%, while obesity almost doubled the odds.
This is after adjusting for other factors that have been linked to COVID-19, like age and being male.
Further analysis has revealed a “dose dependent relationship” between a patient’s BMI and the severity of coronavirus complications.
The same phenomenon appears to be occurring in the US,
The Centers for Disease Control and Prevention reported that out of around 180 adults hospitalised with the coronavirus, 89% had at least one underlying condition, with obesity being the most common for those between 18 and 64.
With the coronavirus outbreak being linked to everything from a faltering global economy to poor mental health, the Queen Mary scientists believe the food industry has a lot to answer for.
“The obesity pandemic is the result of living in food environments where it is difficult not to over-consume calories,” they wrote in The BMJ.
“The global food industry produces and extensively promotes cheap, sugar-sweetened beverages and ultra-processed foods high in salt, sugar, and saturated fat that provide only a transient sensation of fullness.
“It is now clear the food industry shares the blame not only for the obesity pandemic but also for the severity of COVID-19 disease and its devastating consequences”.
Food poverty – an inability to access a nutritious diet, supply chain disruptions and pandemic panic buying all limit access to fresh produce, “thus tilting the balance towards a greater consumption of highly-processed foods and those with long shelf lives that are usually high in salt, sugar, and saturated fat”.
Cardiologist Dr Aseem Malhotra agreed, previously saying the “root of [obesity] is poor diet”.
Speaking on BBC Sounds, he specifically blamed ultra-processed food, which reportedly makes up around half of the average person’s daily calorie intake.
“If you have a poor diet [and] excess body fat, you have chronic inflammation in the body; it’s under stress and being damaged,” he said.
The Queen Mary scientists have also accused the food industry of using the pandemic as a marketing opportunity, for example giving out free doughnuts to NHS staff.
Coronavirus aside, obesity is known to cause type 2 diabetes, heart disease and even certain cancers.
The scientists are therefore calling on the government to do more to “reformulate unhealthy foods and drinks”.
“Reducing salt, sugar, and saturated fat across the board would improve the diet of the entire population and bring even greater benefits for people who are most socially deprived,” they wrote.
“The toll of morbidity and mortality from COVID-19 has made this more apparent and more urgent than ever.”
Why is obesity a risk factor for COVID-19?
Although unclear, there are several theories as to why obese people tend to suffer more with the coronavirus.
“As your infection progresses and the virus infects more and more cells, the demand for oxygen in the tissues is much higher for an obese individual than it is for a lean individual”, Dr Dyan Sellayah from the University of Reading previously said.
“Eventually the obese body becomes overwhelmed by the lack of oxygen getting to the major organs.”
Although usually mild, the coronavirus can spread from the airways to the alveoli (air sacs) in the lungs, where gas exchange takes place.
The air sacs then become inflamed and filled with fluid or pus.
As the lungs struggle to draw in air, oxygen levels in the blood fall and carbon dioxide accumulates.
“Obesity diminishes lung function through greater resistance in the airways and more difficulty in expanding the lungs”, wrote the Queen Mary scientists.
This may not tell the full story, however.
“Obese people tend to have dysfunctional immune systems; their fat tissue for example becomes a reservoir for immune cells known as macrophages,” said Dr Sellayah.
“While these cells reside in our fat under normal circumstances, in obesity they are at higher frequency and become more troublesome.
“They start to secrete inflammatory cytokines [immune-fighting proteins], and negatively impact on immune and metabolic health.
“It is likely the immune response to the virus is therefore ineffective in obese individuals”.
Cytokines are released to help regulate immunity. Excessive amounts can lead to a “cytokine storm”, which triggers hyper-inflammation.
The enzyme the coronavirus uses to enter cells, ACE-2, may also be present in higher amounts in obese people.
“Whether this is the result of higher ACE-2 expression in the adipocytes [fat cells] of people with obesity or having more adipose [fat] tissue in general (and thus a greater number of ACE-2 expressing cells) is not yet clear,” wrote the Queen Mary scientists.
“The adipose tissue of people with obesity may therefore be a potential target and viral reservoir for [the coronavirus] before it spreads to other organs”.
While not a coronavirus strain, flu has been shown to be more dangerous in those carrying excess weight.
In 2009, 61% of the people hospitalised with swine flu in California who later died from the infection were obese.
Obese adults have also been found to “carry” flu viruses for 42% longer than their slimmer counterparts.
What is the coronavirus?
The coronavirus is one of seven strains of a virus class that are known to infect humans.
Others cause everything from the common cold to severe acute respiratory syndrome (Sars), which killed 774 people during its 2002/3 outbreak.
Since the coronavirus outbreak was identified at the end of 2019, more than 7 million cases have been confirmed worldwide, according to Johns Hopkins University.
Of these cases, over 3 million are known to have recovered.
Globally, the death toll has exceeded 411,000.
The coronavirus mainly spreads face to face via infected droplets in coughs and sneezes.
Symptoms commonly include fever, cough and a loss of taste or smell.
The coronavirus has no “set” treatment, with most patients naturally fighting off the infection.
Those requiring hospitalisation are given “supportive care”, like ventilation, while their immune system gets to work.
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