Storing Sports Nutrition Supplements
I often get asked about how heat and humidity can affect sports nutrition supplements such as protein, creatine, branched-chain amino acids, and others during shipping or while storing at home. I often see athletes with protein and amino acid containers well over a year old.
For the most part these supplements are made to stay on the shelf for months at a time, and the virtue of this is a subject for another discussion. Per the manufacturer, these products are quite stable and should not degrade unless you put them in temperatures exceeding 115°F or 46°C. Realize however that once they are open and moisture enters the dry powder, these supplements can begin to degrade. And storing the supplements in a refrigerator will only increase the chance that moisture will accumulate due to condensation. This is the reason it is not advisable to keep these powdered supplements in the refrigerator.
Ready to drink liquid supplements such as sports drinks, amino acids, in creatine are very susceptible to degradation. And it may be best to keep these types of supplements in the refrigerator.
If you do decide to take the supplements, realize it is usually better to consume them through diet. I would recommend using fresh supplements that are stored properly and not years old.