Evaluation of dietary supplementation and/or herbal food consumption habits and common beliefs on their effectiveness during the COVID-19 pandemic

The survey found that 35.3% of participants used DS/HF for protection against COVID-19, and 61.7% used them for treatment. Vitamin C, vitamin D, and multivitamin-multimineral were the most commonly used supplements, while citrus, lemon juice, and ginger were common herbal foods. A majority believed these products were effective, with vitamin C, vitamin D, citrus, and garlic being most believed to be protective and therapeutic. Most DS/HF were recommended by physicians. The study noted that most participants believed DS/HF could be used as substitutes for medicine and were more reliable than treatments, though most did not see them as vaccine alternatives. Limitations include the cross-sectional design, unequal sex proportions, convenience sampling via social media, exclusion of individuals over 65, and self-reported data, which limit generalizability and causal inference.