Colds are one of the leading causes of medical visits and absenteeism from work and school. Anything that helps cold symptoms can bring many social and personal benefits.
Zinc supplements have been reported to help reduce cold symptoms and possibly prevent the development of colds. However, these conclusions continue to remain controversial. Researchers, from the Post Graduate Institute of Medical Education and Research, India, set out to evaluate studies from a 36 to 44 year collection, to ascertain if any valid conclusions could be made from randomised, double-blind, placebo-controlled studies (often well designed studies, with little room for error) (Singh & Das, 2011). In their assessment, Singh and Das (2011) only included studies that used zinc for at least five days for treatment, or five months for prevention (Singh & Das, 2011).
In this study, Singh and Das (2011) evaluated 13 therapeutic trials with 966 participants and two preventive trials with 394 participants. After seven days of treatment, the zinc groups had 55 percent fewer subjects presenting with cold symptoms than did particpants in the control groups. In the long term prevention study, it was found that 36 percent fewer colds developed, and there were fewer school absences and antibiotic prescriptions.
In addition to zinc, other nutrients such as vitamin C can help with colds if given in adequately large doses. Echinacea and garlic might also be helpful.
Singh, M. & Das, R.R. 2011. Zinc for the common cold. Cochrane Database Systematic Review, 16, 2, :CD001364.