But the elephant in the room is that the baseline general health in many western populations were already in a horrendous state to begin with. In the UK and USA more than 60% of adults are overweight or obese. How is this relevant to COVID-19?
OBESITY, THE REAL KILLER BEHIND COVID
It is well known in the medical literature that excess body fat induces immune dysregulation and chronic inflammation which is directly linked to the cytokine storm that is responsible for Acute Respiratory Distress Syndrome seen in influenza and other respiratory viruses. (4)
For example, in 2009 61% of patients admitted to hospital in California that died from H1N1 Influenza A were obese, which was 2.2 times more than the prevalence of obesity within the state population. Multivariate analysis suggested obesity was a novel risk factor for mortality from the virus. (5) Furthermore, obese adults shed influenza A virus 42% longer than non-obese individuals suggesting an additional role in transmission. (6)
Data from the first 2204 patients admitted to 286 NHS ICU’s with COVID- 19 reveal that 72.7% of them were overweight or obese. (7)
Several years ago, a senior advisor personally expressed major concern to me about then-Mayor Boris Johnson. “I’m worried about his health Aseem. He’s significantly overweight and doesn’t look well.” This is despite the fact that Boris would regularly cycle to his office at City Hall. There’s no such thing as being fat and fit. (8)
We shouldn’t ignore the fact that 50-60% % of the 1.4 million NHS workforce are themselves overweight or obese too, not surprising when more than half of the British Diet is ultra-processed food (9) and three quarters of food purchased in hospitals is unhealthy. (10) South Korea which has one of the lowest prevalence of obesity in the world could in part explain it’s low mortality rate form the virus.
But more clinically important than BMI, tied to waist circumference is the prevalence of chronic metabolic disease which can affect many of “normal” weight. Furthermore, sarcopenic obesity may misclassify many elderly patients to having a normal BMI on hospital admission with COVID-19. Only 12.2 % of American adults are considered metabolically healthy, with less than a third of normal weight people also in this category (11). It’s likely the statistics are not dissimilar in the UK. In addition, normal weight metabolically unhealthy have a more than three-fold risk of all-cause mortality and cardiovascular events than those who are normal weight and metabolically healthy. There’s no such thing as a healthy weight, only a healthy person.
