Evidence Level
Zinc is an essential micronutrient that plays a critical role in immune function and overall health. Singh and Das (2013) conducted a Cochrane review of 18 randomized controlled trials (RCTs), demonstrating that zinc lozenges or syrup significantly reduced the duration of cold symptoms when administered within 24 hours of symptom onset. Prasad (2008) further elucidated the immunological mechanisms, showing that zinc is essential for nearly every aspect of immune function, including T-cell development in the thymus, natural killer cell activity, and cytokine production.
Recent studies have expanded on zinc's therapeutic potential. Hsu et al. (2024) performed a systematic review and meta-analysis of six RCTs involving 739 women, highlighting zinc supplementation as an effective management strategy for primary dysmenorrhea. Additionally, Ali et al. (2024) reviewed 38 RCTs, concluding that zinc supplementation reduces the duration of acute watery diarrhea in children but may increase the risk of vomiting.
Zinc deficiency remains a significant public health issue, particularly in vulnerable populations. Zupo et al. (2022) found that 54% of Crohn's disease patients and 41% of ulcerative colitis patients exhibited zinc deficiency, underscoring the need for targeted supplementation. Furthermore, Banik and Ghosh (2022) reported that coronary artery disease patients had significantly lower serum zinc levels compared to controls, based on a meta-analysis of 10 studies involving 614 cases and 508 controls.
Overall, zinc plays a vital role in immune support, with robust evidence supporting its use in treating colds, managing dysmenorrhea, and addressing deficiencies in various clinical populations.