Initial Posting: 7/21/2012    Last Update: 6/12/2019
Answer: Many vitamins and other supplements can degrade faster and lose effectiveness when exposed to excessive heat, light, oxygen in the air, or humidity. Even under ideal conditions, vitamins normally degrade over time, but this process is accelerated by poor storage conditions. Although overly degraded supplements may not be unsafe to take, you won't receive the amount of ingredient stated on the label and may not get the desired effect.
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