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How Long Will Whey Keep?

How Long Does Whey Protein Last For? We Take A Look At The Shelf Life of That Cannister of Whey Protein

Dear Fitness Nerd,

I have a quick question about the shelf life of whey protein powder.  My ex boyfriend left a 5lb tub of Optimum Nutrition 100% whey protein powder in our apartment, but I can’t seem to find an expiration date on it. We’ve been broke up for about a year, so I know it’s at least 12 months old. It still has the seal on it, so I think he may have bought it right before we split. Is it safe to use? And do you have any idea how long it will keep?  optimum-nutrition-whey-proteinThanks! –  Tasha (Las Vegas, NV)

How Long Does Whey Protein Last For?

Normally, whey protein powder will have an expiration date somewhere on the cannister — it’s required by law.  Optimum Nutrition typically stamps the expiry date for whey on the plastic wrapper near the top of the tub.

In general, whey protein powders — especially an isolate powder or 100% whey product with a high proportion of isolates — will have a very stable shelf life.

Oxidation & Rancidity: The Real Enemy

Protein itself, when it’s been defatted and “dehydrated” (as the case is with whey protein powders), is not particularly prone to rancidity. Rancidity is the result of oxidation in fats and oils, which changes their structure for the worst. This can be caused by heat, light, oxygen, or a combination of the three.

However, most 100% whey protein powders contain very little fat.  In fact, the Optimum Nutrition whey powder your boyfriend left in the apartment has only 1.5 grams of fat.  So provided it was stored in a cool location, it should have a shelf-life of at least a year — and probably closer to two years.

Most food manufacturers tend to be quite conservative with their expiration dates, because they know that people keep foods around for longer than they intend, and often don’t pay much attention to the expiration dates.

Just think about that bottle of mustard in the fridge — I bet if you checked it, it’s at least a year out of date.  Yet, it’s probably still fine.

Whats the Real Motivation Behind Expiration Dates and Shelf-Life?

Supplement and food producers know people keep foods beyond their expiration date, so they low ball the shelf-life to take this into account.  I also helps hustle more product.

Plus, they don’t want any legal issues if someone downs a scoop of four-year-old whey protein and gets the “runs” the next day because they also had a coney dog and chili-cheese fries the night before from some joint of “questionable cleanliness.”

Personally, I consume a lot of whey protein powder, and keep little bags of the stuff all over the place: in my gym bag, my desk drawer at work, my laptop bag and even my luggage pockets. Some of it I know is at least two years old and I’ve never had any issues with it.

What About Protein and Vitamin Breakdown?

You might hear people talk about “protein breakdown” on fitness message boards when they discuss how long whey will keep, but there really isn’t too much to worry about here.

Protein is actually pretty tough stuff — it’s going to take more than 24 months sitting on a shelf to degrade its chemical properties.  Remember, it takes some powerful enzymes to break down proteins during digestion and merely resting in a sealed container isn’t going to do this.

Yes, the manufacturer might fortify the protein powder with additional vitamins and minerals that can lose their potency with time, but even this concern is probably overstated.

study by the U.S. Food and Drug Administration (FDA) found that many drugs — both over-the-counter and prescription — have shelf lives that far exceed the manufacturer’s recommended expiration dates.  In some cases, the drugs maintain their potency for as long as 15 years.

Should I Drink The Whey?

The best approach here is to use common sense.

I’m not recommending that people throw aside caution and start downing out-of-date foods or vitamins.

However, in the case of whey protein, there is little harm in trying the protein powder. Open it up and mix some with water.  If it has any “off” flavors or smells, or causes any kind of upset stomach, then throw the stuff out and buy yourself a new tub of whey.

Whatever you decide to do, there is very little risk of any type of serious illness as result of ingesting a single-serving of “out-dated” whey powder.  In your specific case, Optimum Nutrition makes an excellent product that I use myself, and I know I have downed some stuff that is “out-of-date.”

I’m still alive.

But if this is something you are really worried about, skip the guess-work and just chuck the mystery whey powder and buy some fresh stuff.  The money you save often isn’t worth the mental anguish.

But that’s your call.

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Comments (13)

  1. Berto at PricePlow (1 comments) says:

    Only one way to find out – Open it up and take a whiff!  If it’s rancid-smelling, dump it.   I trust that a sealed ON 100% Whey container will be fine.

    This is our featured whey product – it’s great!  See my website for price comparisons between many stores.

    If you try it and start getting indigestion or bad gas, toss it immediately.  I still think it’ll be fine.

  2. David (7 comments) says:

    how much whey protein should a person take?

  3. Will Werner (4 comments) says:

    I find that Optimum Nutrition’s whey protein powder tends to last much longer than other brands such as muscle milk. This is a fantastic post so keep up the good work, FitnessNerd!

    Signed, Crew

  4. Mo (1 comments) says:

    what if the tub has been open for about 5 months?

    StayFitNutrition (1 comments) says:
  5. Hello David, to answer your comment of How much whey should a person take, it depends on a few factors such as weight and how much protein you already eat. If you are trying to build muscle you should have about 1 gram of protein per Lb of body weight you want to be. For example if you want to be 180 lbs, you need to have 180 grams of protein a day. That includes protein from the foods you eat and protein powders. Also you need to take into consideration when you have protein; your body cannot digest more than 35 grams of protein per sitting. The additional protein does not benefit you and just becomes additional calories, so try and watch your protein intake per sitting to get the best results. Also a few months ago, Consumer Reports came out with a report on Protein powders, stating that some of them may be high in toxic metals. I love Consumer reports and read that magazine frequently, but they failed to mention that yes some protein powders are higher in toxic metals, but many of these metals are not uncommon in the environment, whether it’s caused by pollution, contaminated soil, or naturally occurring. If they did the same test with any vegetable from the supermarket they would also find trace elements of toxic metals so this is not isolated to just protein powder. I do however; take consumer reports research with a grain of salt and try to limit my protein powder consumption to no more than 2 servings a day while getting the rest of my protein from food. I hope this answer helps. Good Luck.

  6. Charlie Roberts (1 comments) says:

    Whey Protein will actually last much longer (its efficacy) than its expiration date.  I agree with the previous comment by Berto, that smelling it can’t help determin if it is still okay to consume.  I know that retail stores are mandated by Federal Law to discard it after the expiration date, but that doesn’t mean it is bad or lost its efficacy.

  7. Charlotte – Protein powder for women (1 comments) says:

    I never thought about how long it lasts before. I guess I’ve been naive and just assumed it could last until there’s nothing left. Good thing it’s not too risky according to this post. I use it somewhat fast anyway, so I feel  safe. Thx for the post

  8. sndysachs (1 comments) says:

    Every food item has an expiry date, beyond which it becomes unfit for eating. Strict laws should be introduced to make it mandatory to mention the packing date and expiry date on all packaged food items.

  9. Kaj Peterson (1 comments) says:

    And how much shelf life does whey have before the the xpiry date? I wanna know how much time is there normally between the production and expiry date.

  10. panysher (1 comments) says:

    i  have purchased Dr. Mercola’s PURE POWER PROTEIN>>>> and what i see on the container is MAG ON 12/29/2011…. its not all that clear. want to know it meaning and if it has expired or not?

  11. brahbrah (1 comments) says:

    Its also possible to add out of date whey powder to dogs/cats food, ofcourse whey should not be in a totally degraded condition. Especially cats need high protein diet but be careful with the serving size! I just recommend consulting a veterinarian before dumping that nutritious powder out of the way, dog/cat shelters could also make use of it.

  12. Oliver L James (1 comments) says:

    Protein does not work the way everyone who is not a chemist thinks. Proteins that make you strong or repair muscles or for hair etc are made only in the body by RNA/DNA dynamics. All proteins work from within not from your steak – raw or cooked. You can make protein in a lab but then it must be injected into the muscle or the blood – directly. Like steroids or insulin. There is no “shelf life” for proteins out side a living organism – even in an organism the shelf life can average only 2 days.               Oliver