Does Glutamine Expire

Glutamine PowderGlutamine is a popular bodybuilding supplement that is used to speed recovery and improve muscle growth. It is typically purchased in large quantities, which often ranges between one and five pounds. While it is considerably cheaper to buy it this way, it presents a problem. If you were unable to use all of the product by the expiration date listed on the package, you may be concerned that it’s no longer fit to use.

But Does Glutamine Expire?

Like most supplements, glutamine can indeed expire, but you can typically expect it to stay fresh for up to 90 days after the expiration date has passed. If your glutamine is older than this and you continue to take it, however, you needn’t worry about adverse health effects. Instead, the product merely loses its potency. If it’s old enough, it may not have any effect at all or the effects may be greatly diminished. If your glutamine is old, it may develop a yellowish tint to it, which is caused by oxidation, and may also form hard clumps. Because this supplement is among the cheapest available, it’s recommended that you simply replace it if you’re uncertain of its freshness. Fortunately, there is an exception to this rule. A container of glutamate that is past the expiration date, but is still sealed, is normally still as fresh as the day you bought it.

Prolonging Glutamate’s Shelf Life

If you’re concerned about making your supply of glutamine last, there are several steps you can take to ensure its freshness.


It’s recommended that you keep your glutamine in your refrigerator in order to maintain its potency. The low temperatures slow the product’s degradation and minimize oxidation. The best place to keep it is in the coldest part of your refrigerator, either toward the back or in the crisper drawer.

Airtight Container

The container your glutamine powder came is is most likely not airtight. Plastic is a porous material that allows oxygen through fairly easily. When oxygen comes into contact with the product, it damages the chemical structure causes it to lose potency rapidly. It’s a better idea to keep it sealed in a mason jar or hermetically sealed container to prevent this from happening.

Moisture Control

Like oxygen, moisture is also an enemy of supplement potency and freshness. However, glutamine has been shown to be particularly vulnerable to this. A good way around this is to keep a moisture-absorbing packet in your container of glutamine. These handy inventions soak up and retain any moisture in the product, helping it stay fresh longer.

Protect From Heat and Light

Glutamine can also be rendered ineffective by prolonged exposure to heat and light. Both of these factors accelerate the natural breakdown of chemical compounds, which is why some supplements are sold in dark glass containers. Unfortunately, artificial light is just as good at doing this as sunlight. It’s strongly recommended that you keep glutamine, even sealed containers, in as cool, dry and dark a location as possible. Never leave it sitting next to your stove or near windows.