Weight and COVID-19 Immunity: Vaccination vs. Infection

A recent study found that excess weight affects how the immune system responds to COVID-19, showing differences between post-infection and post-vaccination immunity. Led by Marcus Tong from the University of Queensland, the research suggests that being overweight, not just obese, makes SARS-CoV-2 infections more severe and changes the immune response.

In a unique study group infected at the beginning of the pandemic, blood samples were taken three and 13 months after infection. Those with a higher body mass index (BMI) experienced a faster decline in immune response, especially against certain variants. Interestingly, vaccinated individuals did not show this decline, highlighting the potential superiority of vaccine-induced protection for overweight people.

The study included participants who remained uninfected and unvaccinated for 13 months, allowing researchers to isolate the effects of natural protection versus vaccination. Five months after their second vaccine dose, participants who had never had COVID-19 were included. Regardless of BMI, no significant differences in immunity were found in this vaccinated group.

The study emphasizes the importance of vaccination for overweight individuals, as their infection risks and weakened immune responses may increase the chances of reinfection. Dr. Kirsty Short from the University of Queensland stresses the crucial need for vaccination in this group.

However, for those with severe obesity (BMI > 40 kg/m2), a separate study in Nature Medicine in May 2023 showed a different scenario. Despite initially similar vaccine responses between obese and healthy-weight individuals, those with severe obesity experienced a quicker decline in immunity effectiveness, leading to more hospitalizations and deaths.

While a third vaccine dose restored immunity in severe obesity cases, it declined faster afterward. The study authors suggest considering more frequent COVID-19 vaccinations for people with severe obesity to ensure they have protection comparable to those with a normal BMI, considering the widespread prevalence of obesity globally.

The medical information on this site is provided as an information resource only and is not to be used or relied on for any diagnostic or treatment purposes. This information does not substitute for professional diagnosis and treatment. Please do not initiate, modify, or discontinue any treatment, medication, or supplement solely based on this information. Always seek the advice of your health care provider first. Full Disclaimer

Share this post