A. Jeffrey Blumberg, PhD, director of Tufts HNRCA Antioxidants Research Laboratory, explains: Vitamins and minerals promote cell health through the maintenance of cellular defenses, growth, metabolism, reproduction and structure. An inadequacy or deficiency of one or more of these nutrients can lead to poor functioning of the cell or even cell death. Antioxidants typically found in multivitamins include essential vitamins (C and E) and minerals (selenium, zinc) and may also include non-essential bioactives like carotenoids, phenolic acids, polyphenols and/or ubiquinols.
The fundamental issue here is the prohibition by FDA (and FTC) regulations of foods and nutritional products to claim in any fashion that they can be used to diagnose, treat, cure or prevent any disease without being classified as an unapproved and, thus, illegal drug. Thus, most food and supplement companies instead abide by FDA regulations allowing statements on labels and in advertising about the effect of nutrients on the structure or function of the body. Even after 20 years of use (i.e., the Dietary Supplement and Health Act of 1994), these statements remain confusing to many consumers and also controversial (and, thus, the subject of a great many lawsuits). The FDA itself defined structure/function claims but does not require its pre-approval of them. Promoting cell health is such a claim.