Does Protein Powder Expire? What to Know According to Experts

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Many people who exercise frequently use protein powder, but even non-athletes use these high-protein supplements as an easy and quick source of protein. We depend on protein powder to help build muscles, but what if you're concerned your protein powder smoothies are growing more than muscles? If bacterial growth or spoilage worries you, keep reading. We’ll tell you all there is to know about your protein powder’s use-by-date so you can maintain your wellness routine in the healthiest way possible, plus provide some tips for identifying whether the supplement is still safe to consume.

Benefits of Protein Powder

For muscle growth and maintenance, it is essential that daily protein needs are met. Protein powder can serve as a way to ensure you take in the necessary amount of protein because it’s convenient and inexpensive. It’s also versatile because it supports weight loss and muscle gain. You can add it to various beverages and drink it at different times throughout the day. Not to mention the fact that protein powder can taste really delicious as well.

The International Society for Sports Nutrition (ISSN) regards protein supplements as “a practical way of ensuring intake of adequate protein quality and quantity while minimizing caloric intake.” They also state that protein should be broken up evenly throughout the day for best results. Therefore, having a protein shake on hand is great for any time throughout the day.

How Can I Tell If My Protein Powder Is Good?

Ever clean out your pantry or cupboard just to find a container of old protein powder? You dust it off and then realize you’d wanted to start incorporating it into your daily routine and forgot all about it. But you can’t remember when you bought it, and wonder if it’s still good. How can you tell?

Start with the expiration date. Search the container of protein powder for the date, often printed somewhere on the lid or the bottom. If it’s past the expiration date, then toss it. If it’s not past the expiration date, but you’re suspicious of spoilage, try a few of these things:

• Smell: Check for a rancid smell.
• Texture: Look for caking or clumping of the powder.
• Color: Determine if the color has changed since it was originally open. It will usually become darker with age.
• Taste: You probably want to skip this one if you determine any of the above are true. Rancid protein powder often has a bitter taste.

Remember, regardless of the type of protein powder—whether you choose vegan protein powders, egg white, collagen, whey or casein—even the best protein powders expire despite the protein source. So be on the lookout for these things.

Is It Okay To Use Expired Protein Powder?

The expiration date is a guide printed on almost all food products that inform the consumer of the date at which a food is no longer guaranteed to be fresh. There’s evidence that when protein powder is no longer good, the protein itself starts to degrade, which will render the powder less effective. One study showed a decrease in lysine (an amino acid) in expired powder.

Although these dates should usually be followed, there is some research that illustrates foods are often safe to eat a bit beyond that date. Whether or not it’s okay to use a protein powder that is past its expiration date depends on how far past the date it is and if you notice a rancid smell, change in texture or color or a bitter taste.

How to Store Protein Powder for the Long Term

Do you usually store your protein powder on top of the fridge for easy access? You might want to reconsider. Storage conditions play a large role in protein powders’ shelf life, and heat (like that emitted from a refrigerator) can speed up the deterioration process regardless of whether you’re storing pea protein or whey.

Research has shown that storing protein powder above 95 degrees Fahrenheit significantly reduces the protein’s shelf life. For this reason, be sure to keep your powder in a cool dry place, and out of hot cars or garages in the summertime. An enemy of dried powder is water: Water causes changes in texture and encourages microbial growth. Thus it’s important to store your protein powder in a dry place and avoid exposing it to excess humidity.

Our Favorite Protein Powders

Looking to refresh your stash of expired protein powder? Here are some of our favorite high-quality protein powders to get you started. Prefer a vegan-friendly option? Check out our article on the best plant-based protein powders.

XWerks Grow

XWerks Grow is a high-quality protein powder that contains the cleanest and purest form of whey protein, known as whey protein isolate. XWerks’ whey comes from grass-fed cows in New Zealand, which means the milk used to create the whey contains no hormones, pesticides or antibiotics that can be passed onto consumers. With a minimum of 23 grams of protein per serving, this protein powder is soy- and gluten-free and contains no artificial sweeteners, colors or flavorings. This protein powder comes in Chocolate, Vanilla, Strawberry and Peanut Butter flavors and contains over six grams of BCAAs in each scoop.

Check out our XWerks Grow Protein review for more information.

Transparent Labs Grass Fed Whey Protein

Transparent Labs Whey Protein is sourced from grass-fed and finished American cows. With a whopping 28 grams of high-quality protein isolate per serving, and no artificial sweeteners, hormones, colors or preservatives, this protein powder is a solid choice for a clean protein boost for your diet. As with other Transparent Labs products, the protein has minimal additives and is third-party tested with certificates of analysis and composition provided right on their website. It comes in a variety of flavors including French Vanilla, Chocolate Peanut Butter, Oatmeal Chocolate Chip Cookie, Milk Chocolate, Cinnamon French Toast, Vanilla Peanut Butter and more.

Check out our Transparent Labs Whey Protein review for more information.

Swolverine Whey Protein Isolate

Swolverine Whey Protein powder comes in the form of whey protein isolate and has 26 grams of protein per serving. This high-quality protein comes from grass-fed cows free of rBGH. Additionally, it has two different digestive enzymes to help reduce stomach discomfort and maximize absorption of the protein. This whey protein isolate is made in the USA, non-GMO, gluten-free and created and sold by a women-owned company. It’s available in Vanilla, Chocolate, Honey Cinnamon Peanut Butter and Mint Chocolate Chip flavors.

Protein Powder FAQs

What is the shelf life of protein powder after opening?

Unfortunately, there are no specific research studies available that would give us a clear answer here. In general, many like to consume dry goods within three months of opening the container, but you can also look out for quality changes such as color darkening, clumping, a rancid smell or a bitter taste.

What are the side effects of taking expired protein powder?

Oftentimes, protein powders are still good beyond their expiration date. However, if the protein powder is rancid or contaminated with a pathogen, you could likely expect gastrointestinal symptoms at a minimum.

Does whey need to be refrigerated?

Most often, whey protein does not need to be refrigerated. Despite originating from dairy and the need for most dairy products to be refrigerated, the processing and drying of whey protein allow it to be shelf stable. That being said, you might extend the shelf life by storing your protein powder in the refrigerator.

How long does unopened protein powder last?

Unopened protein powder should last at least until the expiration date. If it is stored in a cool, dry environment it may even last beyond the expiration date.

What does enjoy by date mean?

Like the “best by” date, the enjoy by date simply means that the protein powder will maintain its freshness by this date. It’s not necessarily an expiration date, but it’s the date that the company will likely guarantee freshness by.

Final Thoughts

Despite protein powders’ versatility and convenience, they do lose quality over time. Although protein powders can often last longer than their expiration date, it’s important to be aware of the date listed; it’s the surest way to guarantee freshness. If you have suspicions about it going bad, be sure to check the color, smell, texture and taste for freshness. And as the saying goes, when in doubt, throw it out!

Prices are accurate and items in stock as of publish time.