Comparison of Blood Parameters Between Omnivores and Lacto-Ovo Vegetarians Post-COVID-19: A Pilot Study Done in a Country City in the South of Brazil

Among the most significant comorbidities associated with the progression of COVID-19 to more severe stages, studies have reported a high prevalence of overweight and obesity, often resulting in complications that require hospitalization and intensive care. As obesity can, in many cases, be linked to lifestyle, dietary habits may influence physiological parameters, particularly in the period following viral infections such as COVID-19. This pilot study aimed to compare the blood parameters of individuals with different dietary patterns (omnivores and lacto-ovo vegetarians) after COVID-19 infection using principal component analysis (PCA). All participants were residents of the same city (Campo Mourão, Paraná State, Brazil) and were infected during a similar time period (January 2022 ± 2 months). Blood analysis data were collected from 20 volunteers, all evaluated at the same clinical analysis laboratory. The parameters assessed included leukocytes, red blood cells, hemoglobin, hematocrit, erythrocytes, platelets, total cholesterol, high-density lipoprotein (HDL) cholesterol, non-HDL cholesterol, low-density lipoprotein (LDL) cholesterol, glucose, ferritin, vitamin B12, vitamin D, vitamin C, and calcium. PCA results indicated distinct differences in blood profiles between most lacto-ovo vegetarians and omnivores. Lacto-ovo vegetarians were associated with higher levels of HDL cholesterol, ferritin, glucose, platelets, and hematocrit, while omnivores showed higher levels of LDL cholesterol, total cholesterol, vitamin B12, vitamin D, and hemoglobin. Among the parameters evaluated, only vitamin D showed a statistically significant difference between the groups (<i>P</i> < .05). These preliminary findings suggest that dietary patterns may influence certain blood parameters in the post-COVID-19 recovery period. Further research with a larger sample size is needed to confirm these associations and to better understand the potential role of diet in postinfection metabolic responses.