There is a problem with nearly all Vit C supplements. Low purity. This product is no exception. All of the active and inert ingredients listed of the label of this product are colorless, yet the color of the caplets is light amber. Without specific analysis, it is impossible to say for certain which component or components are impure, but there is a very high probability that it is the ascorbic acid. In the presence of moisture (humidity) and air Vitamin C readily oxidizes to dehydroascorbic acid. Dehydroascorbic acid is amber in color; precisely the color of these caplets, and virtually all other vitamin C caplets and tablets commonly available in drug stores. Once the tablets are manufactured and placed in air tight containers very little additional oxidation should occur. This strongly suggest the use of low grade Vitamin C to manufacture these caplets, and virtually all other Vitamin C tablets readily available. To avoid this problem, one might try to acquire high purity ascorbic acid powder, which should be pure white. But again, it would not be surprising to find that the pure powder form also has an amber cast. A minor problem in addition to the obvious lower purity of this product is the caplets themselves. They have ridges that make them hard to swallow. The best caplets are smooth and coated, making them much easier to swallow.
It is stated on the bottle that this product is manufactured by Rexall Sundown, Inc., Boca Raton, Fl. There is no definite indication of where it is manufactured, but even if manufactured in the U.S.A. one strongly suspects that the active ingredient is from off shore where the purity standards are more lax than in the U.S.A.
Incidently a small amount of dehydroascorbic acid in ascorbic acid is acceptable, but if the manufacturer is going to market this product as Vitamin C, which is ascorbic acid, then at the least they should show the analysis on the label giiving both the percent by weight of Ascorbic acid and of Dehydroascorbic acid. The color of these tablets is such that one may assume the dehydroascorbic acid content is substantial.