Pandemic Preparedness: Maintaining Adequate Immune Fitness by Attaining a Normal, Healthy Body Weight

In addition to developing effective medicines and vaccines, pandemic preparedness also comprises general health-related, behavioral, and psychological aspects related to being more resistant in the case of future pandemics. In the context of the 2019 coronavirus (COVID-19) pandemic, recent research revealed that reduced perceived immune fitness was the best predictor of reporting more frequent and more severe COVID-19 symptoms. Up until now (June 2022), during the COVID-19 pandemic, the majority of patients who have been hospitalized were characterized as being overweight. It is therefore essential to further evaluate the relationship between body mass index (BMI) and immune fitness. This was performed by analyzing pooled data from previously published studies, conducted among N = 8586 Dutch adults. It was hypothesized that attaining a normal, healthy body weight is associated with optimal perceived immune fitness. The analysis revealed that a deviation from normal weight (i.e., having a BMI outside the range of 18.5 to 24.9 kg/m²) was associated with significantly reduced perceived immune fitness, as assessed with the immune status questionnaire and a single item perceived immune fitness scale. The effects were significant for both underweight and overweight groups and most pronounced for the obese groups. The results suggest that attaining a normal, healthy body weight might significantly contribute to maintaining adequate perceived immune fitness. Therefore, attaining a normal body weight might be an essential component of pandemic preparedness and should be supported by creating awareness and promoting the importance of regular exercise and the consumption of healthy food.