Study shows obesity causes reduced response to COVID shots...

New research published in SciTechDaily has added weight to an already significant body of evidence showing that natural immunity to COVID is far superior to vaccine-conferred immunity.

A study conducted by researchers at Istanbul University in Turkey examined antibody levels in obese people as compared to normal-weight controls, and also (unusually, for scientific studies) distinguished between people with prior SARS-CoV-2 infection and those without.

Obesity has long been known to be a significant risk factor for hospitalization due to COVID and also for dying of COVID, the risk increasing as BMI increases. A number of reasons have been suggested for the higher risk, including a greater number of ACE receptors in obese people’s bodies, lower oxygen saturation of blood due to impaired ventilation of the lungs in this population, and the damaging effect of excess weight on general immunity.

The Istanbul researchers set out to discover whether obese people had a specific response to COVID vaccines. They already suspected this might be the case, as obese people have been shown to have a reduced response to vaccines for influenza, hepatitis B, and rabies.

Their findings confirmed this suspicion. Trial participants in the study group were injected either with the Pfizer-BioNTech product, or the Chinese CoronaVac shot. Four weeks later, obese people who had taken the Pfizer shot had antibody levels three times lower than those in the normal-weight control group. Those who took the CoronaVac shot had levels 27 times lower.

These results pertained to people with no prior SARS-CoV-2 infection.

For those with a prior infection, the results were totally different. There was no significant difference between the antibody levels of the obese and normal-weight cohorts, regardless of the origin of the vaccine.

The study’s lead author, Professor Volkan Demirhan Yumuk, concluded that

... immune memory induced by prior infection alters the way in which people respond to vaccination...

but refrained from drawing further conclusions on the possible role played by COVID vaccines in actually damaging the human immune response, even though the body of data supporting this theory is growing.

Curiously, Prof. Yumuk added that the results also

... reinforce the importance of prioritizing and increasing vaccine uptake in this vulnerable group...

The data he obtained, though, does not seem to support this assertion.