What Actually Happens to Your Body When You Drink Expired Protein Powder
Buying a big jug of protein powder is basically a rite of passage for anyone who's ever touched a barbell. For beginners, it usually sits on the shelf right next to their bubble gum-flavored tub of pre-workout and their hopes and dreams. And while whey has undoubtedly ruled the GNC shelves for decades, today's market has exploded into a buffet of alternatives from soy and plant- based blends to more "exotic" options like collagen, rice, egg white, and even beef protein powder.
Beyond the macro ingredient itself, many powders also contain carbohydrates, fats, and vitamins that are included to help consumers balance their training block. Most also have additives, thickening agents designed to extend shelf life, and flavor enhancers included to make sure your shake tastes like "Cookies and Cream", instead of the chalk bodybuilders used to slurp down in the 60s.
Anyone who's been working out long enough has some sort of supplement graveyard. You know the tubs you thought you'd get through before the newest supplement came out and scooted it to the back of your shelf, only to be rediscovered months after the "Best By" date has passed. It leads to the inevitable question every lifter eventually asks while staring at a dusty scoop—is this still safe?
Does Protein Powder Expire?
BPI Sports CEO Chris Mackenzie has been involved with the supplement brand since 2009 and is also a natural competitive bodybuilder. Mackenzie explained that protein powder does have a shelf life (meaning the time the powder is of optimal quality).
“People need to remember that most protein powders are milk-derived, and we all know dairy products have a limited lifespan,” Mackenzie shared. “Through filtering and processing, the whey components of the milk are converted to powder, which is much more stable, but it’s still dairy and hence will have limitations on its shelf life.”
Although all protein powders have a "Best By" date, shelf life is also determined by the packaging and room temperature. There's also an expiration date stamped on many brands’ bottles, but the U.S. Food and Drug Administration does not require this of supplement manufacturers. If they do, they have to provide data to verify why the date is listed.
Related: 18 Dietitian-Approved Foods to Help You Hit Your Protein Goals and Stop Mid-Day Cravings
What Is The Shelf Life of Protein Powder?
Mackenzie reported that most protein powders have a shelf life of two to three years. Other experts have reported similar ranges, with many leaning closer to two years than three. If you’ve invested in protein powder of any kind, then it would be wise to use it sooner rather than later. A 2020 study on soy protein isolate concluded that the longer it is stored without being used, the more likely it may not perform as well nutritionally or functionally, making proper storage and freshness matter more than most people think.
“Plant-derived protein can have a longer shelf life than whey/dairy-derived powders," Mackenzie explained. "However, many plant-based proteins have MCT oils or other fats formulated in, and those components have their own lifespan, sensitivity to heat, and other external sources.”
Registered dietitian and nutritionist Shelley Balls added, “Plant-based protein powders are also less prone to oxidation, whereas whey and casein degrade more quickly.”
More of the same is true for whey. Research in 2023 found that proteins can undergo denaturation, oxidation, clumping, and protein and sugar damage. That means the longer it sits, the more the quality deteriorates. Balls also suggests that storing the protein powder improperly can speed up this process.
“When protein powder is stored next to a heat source or exposed to high humidity, it can spoil,” she adds.
Signs Your Protein Powder Expired
- Different taste after being mixed
- Changes in the color of the powder
- Unusually solid or chunky
- Expanded container due to pressure
Can You Use Expired Protein Powder?
Protein powder isn't exactly cheap, so it’s painful to toss a half-full tub just because you stored it wrong and the date on the plastic told you to. While it might be tempting to power through it to save a few bucks, you should know that you’re likely drinking a degraded product. Even if the powder isn't technically "spoiled," the amino acids and vitamins can break down over time, meaning the shake might not actually be doing much for your recovery.
“Protein powder is more likely to spoil due to the way it’s stored than if it’s past its date," says Registered dietitian Avery Zenker. "Protein powder can be safe past the printed best by date, although quality may reduce over time.”
Can Consuming Expired Protein Powder Make You Sick?
Outside of infant formula, most expiration dates are really about quality rather than safety. Since protein powder is a low-moisture food, it’s a pretty hostile environment for bacteria like Salmonella to grow. In most cases, drinking a scoop of the expired stuff won't actually upset your stomach, but you can bet the potency has diminished. Of course, there’s always that worst-case scenario where you still end up getting sick from it.
How Should You Store Your Protein Powder?
So, what would be the best way to store your protein powder to maximize its shelf life? According to sports nutritionist and personal trainer Alexander Leritz, you want to avoid heat, light, and moisture.
“It is best practice to store your powder in a cabinet, ideally below 70 degrees Fahrenheit," he says. "Additionally, storage in a cabinet prevents damage from sunlight in the form of UV rays, which can accelerate rancidity and break down certain vitamins.”
Similarly, if you make a protein shake, especially if it's whey, you should store it in a cool place and use it within a few hours. If you're making a shake for a workout the next day, pop it in the fridge, and make sure to consume it within 24 to 48 hours.