In a recent small-scale Turkish study, it was found that severe obesity may weaken the effectiveness of vaccines in those who have never been infected by the novel coronavirus. Several other studies have also echoed similar results about patients administered with Pfizer or BioNTech vaccine. According to the study, the antibody level in an obese person is three times lower than a normal-weight individual.

According to the data presented at the European Congress on obesity in the Netherlands, the recipients of other vaccines, such as Coronovac showed antibody levels 27 times lower than the normal-weight person. The study compared the immune responses in 124 subjects with severe obesity and normal body weight with the classification based on the universal Body Mass Index scale. The subjects of the study were divided into 2 groups of 130 normal and 160 obese participants, having received Pfizer/ BioNTech vaccine and Coronovac respectively.

The results showed that both Pfizer/ BioNTech vaccines produced a significant number of antibodies in normal-weight people than Coronovac in the obese. However, further studies are needed to determine if a higher antibody provides greater protection from infection stated the researcher.