Is It Safe to Eat Expired Protein Powder?

If you still think protein powder is only for muscleheads who never leave the weight room, you're sorely behind on the fitness-nutrition times. Protein is an essential macronutrient that helps you recover from tough workouts, build muscle, and stabilize blood sugar so you can maintain good energy. (Here's how much protein you need per day.)

But try as you might, if you're not one to reach for a scoop of whey protein (or soy, brown rice, or casein protein) every time you make a post-workout protein shake, it can be hard to use up those huge tubs of protein powder before the sell-by date. And while you might admit to using things like milk a few days after the carton says it's expired, do the same iffy "rules" apply to protein powder?

Does protein powder go bad after the sell-by date?

Most likely, it's OK to eat, reassures Robert Wildman, Ph.D., R.D., chief protein officer of Premier Protein. He says that since protein powders are such dry products, there's little risk of bacterial growth or spoilage. What's more, the "use by" and "sell by" dates listed on packages indicate the food's quality, not safety—meaning, it's safe to consume foods stamped with "use by" or "sell by" past the date on the label, according to the United States Department of Agriculture (USDA).

What can happen to expired protein powder is that it'll stop tasting so great, he says. "The sell-by date is usually a year or more out, but after a long enough period, the intensity of the flavors can start to fade. It's still safe to eat, but that's when you might want to start cooking with it instead of just adding it to water or milk." Wildman likes to add it to smoothies, pancakes, muffins, or even sprinkle it over oatmeal. (Unflavored Protein Powder You Can Add to Anything and Everything.)

And while the sell-by date doesn't indicate the safety of the product, he does recommend tossing any protein powder once it's a full year past the sell-by date—just to be on the safe side.

How can you tell if protein powder has gone bad?

If you're planning to eat expired protein powder past the sell-by or use-by date, mix up a little in water and do a smell- and taste-test before using it. If it seems rancid or off in any way, trust your nose and ditch it. Ditto if you notice any odd changes in color or texture, or spot some mold.

How do you preserve protein powder as long as possible?

To keep your protein powder tasting great for as long as possible, store it in a cool, dry place, like your pantry. And keep it off the top of the fridge; the heat and humidity can cause it to degrade faster, says Wildman. (Wondering which kind of protein powder is best for you? These are the best protein powders for women, according to nutritionists.)