Category: Supplement stability

While vitamin E is often added to foods and supplements as an antioxidant to extend shelf life, it is itself vulnerable to degradation. But **is vitamin E shelf stable** over the long term once you bring it home? Its longevity depends heavily on its form and storage conditions.

According to chemical stability data, cystine is significantly more stable than its reduced form, cysteine. This relative stability is key to understanding how long does cystine last in various conditions, from a dietary supplement to a laboratory reagent. While the oxidized dimer is inherently robust, its shelf life is not indefinite and is governed by specific environmental factors.