Elevated BMI reduces the humoral response to SARS‐CoV‐2 infection

Abstract

ObjectiveClass III obesity (body mass index [BMI] ≥ 40 kg m−2) significantly impairs the immune response to SARS‐CoV‐2 vaccination. However, the effect of an elevated BMI (≥ 25 kg m−2) on humoral immunity to SARS‐CoV‐2 infection and COVID‐19 vaccination remains unclear.MethodsWe collected blood samples from people who recovered from SARS‐CoV‐2 infection approximately 3 and 13 months of post‐infection (noting that these individuals were not exposed to SARS‐CoV‐2 or vaccinated in the interim). We also collected blood samples from people approximately 5 months of post‐second dose COVID‐19 vaccination (the majority of whom did not have a prior SARS‐CoV‐2 infection). We measured their humoral responses to SARS‐CoV‐2, grouping individuals based on a BMI greater or less than 25 kg m−2.ResultsHere, we show that an increased BMI (≥ 25 kg m−2), when accounting for age and sex differences, is associated with reduced antibody responses after SARS‐CoV‐2 infection. At 3 months of post‐infection, an elevated BMI was associated with reduced antibody titres. At 13 months of post‐infection, an elevated BMI was associated with reduced antibody avidity and a reduced percentage of spike‐positive B cells. In contrast, no significant association was noted between a BMI ≥ 25 kg m−2 and humoral immunity to SARS‐CoV‐2 at 5 months of post‐secondary vaccination.ConclusionsTaken together, these data showed that elevated BMI is associated with an impaired humoral immune response to SARS‐CoV‐2 infection. The impairment of infection‐induced immunity in individuals with a BMI ≥ 25 kg m−2 suggests an added impetus for vaccination rather than relying on infection‐induced immunity.

An update on Long COVID

“…8 Research has also shown that being overweight negatively affects the body's immune response, impairing antibodies to fight the virus. 9 Having said that, being overweight does not seem to affect the immune response generated by COVID-19 vaccines. People cannot be blamed for developing Long COVID because exposure to the infection is almost impossible to prevent.…”