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Does Mass Gainer Expire

Does Mass Gainer Expire & Should You Still Use It?

Mass gainers are a supplement that often get questioned on their effectiveness and whether or not it’s even worth your time (or money) taking a mass gainer.

They are not cheap when looked at per serving, especially compared to a homemade weight gainer which can be made using protein powder and some cheap carb sources like oats, milk, honey, and peanut butter. 

Here, I’ve covered the question: does mass gainer expire, including whether they expire, if you can use them when they expire, and signs that your mass gainer has gone bad that you should look out for.

Therefore, if you are going to supplement with mass gainer and commit to the monthly cost of this product, you’ll want to make sure it will last and not go off. 

What Is a Mass Gainer

Mass gainers are supplements that are designed to help people gain weight, primarily through increasing muscle mass. 

Related – Mass gainer vs weight gainer

Traditionally, mass gainers were horrible-tasting supplements made up of sugar, dairy, and high-calorie ingredients that bodybuilders would chug down and do so as quickly as possible.

They would even contain ingredients like brewer’s yeast and wheat germ to improve gut health so while bodybuilders were trying to get as many “healthy” ingredients into the shake as possible, the end product was nothing like the strawberry shortcake tasting flavors we have today!

In the last couple of decades, however, they’ve become one of the most popular supplements on the market thanks to improvements in the formula used and flavor enhancements. 

Mass gainers are high in calories and contain a significant amount of carbohydrates as well as proteins. They can also contain fats, as well as micronutrients all of which are designed to support the development of muscle mass.

Mass gainers usually come in a large tub and they can be an expensive investment, so you’ll want to get the most out of them as you can! This means you’ll need to know whether these products expire and how long you can safely use them for.

Does Mass Gainer Expire?

Yes, mass gainers do expire. Their expiration date should be listed on the product, usually on the bottom or side of the tub. Generally, this expiration date will be a couple of months to years after your purchase date. Mass gainers can also go off before their expiration date if stored incorrectly.

To expand on this some more, like almost any product, mass gainers will eventually expire. 

This is because the ingredients within mass gainers go off with time. As a result, this means that mass gainers can only be safely consumed before their expiration date.

As mass gainers can expire, this can mean that buying it in bulk isn’t always worth it, as the product might expire and no longer be safe to consume before you’ve finished the tub.

When Does Mass Gainer Expire?

The expiration date of mass gainers varies. Usually, they will have an expiration date that is a couple of months to years after the purchase date. However, if opened, mass gainers can also go off before the expiration date. 

This usually happens if they haven’t been properly stored.

The shelf life of mass gainers varies: some products expire after just a few months, and others will have more generous expiration dates and last a couple of years. 

To find out the expiration date of a mass gainer you’ll need to look at the product as that’s where the expiration date is usually listed. 

However, if opened mass gainers can also go bad before the expiration date. This usually depends on what ingredients it contains, as well as how you store it.

For example, mass gainers containing hygroscopic ingredients (meaning ingredients that attract water) can go off as they attract water from the surrounding air which changes their composition.

Storage is also an important factor to consider. 

If you leave the lid slightly open it can allow moisture to get into the product which can start to degrade the ingredients. This can also happen if the product is left somewhere warm, like a car or on a worktop, or in direct sunlight.

So properly storing your mass gainer is important if you want to extend its shelf life and stop it from going bad before the expiration date.

How to Tell if Mass Gainer Has Expired

The easiest way to tell if a mass gainer has expired is by checking the expiration date on the product. If this date has passed then the product has expired. 

Other signs that your mass gainer has gone bad include clumps in the powder, discoloration of the powder, as well as a bad taste or smell.

Expiration dates are put on products to advise the consumer about when a product will go off. In order to determine if your mass gainer has expired the best option is to check out the expiration date on the product.

Whilst the expiration date is the safest bet to tell if your mass gainer has gone off there can be other signs that the product has gone bad.

Common signs that your mass gainer has expired include clumps. Clumps form when water particles have gotten into the product and started to change their composition. So clumpy powder can signal that the product has gone off.

The discoloration is another sign that the product has gone off. 

Discoloration can happen for different reasons. For example, if mold has started to develop on the product then it will change in color. So if your mass gainer has changed in color it’s likely gone bad.

Another sign that your mass gainer has gone bad is a bad taste or smell. 

Although the smell varies by product, when you first open your mass gainer it will have a noticeable smell. If this smell changes or becomes worse, or if the taste does, then this is a sign it has gone bad. 

Can You Use an Expired Mass Gainer?

You shouldn’t use expired mass gainers. Consuming expired mass gainers can cause side effects and can make you seriously ill. It’s also not likely to be effective anymore as the potency of the ingredients will have deteriorated.

If your mass gainer has expired, you shouldn’t consume it. This is because when the ingredients have expired, or if the product has gone off, they can cause serious health problems if they are consumed.

Consuming expired mass gainers may also be ineffective. Often as ingredients expire their potency is reduced significantly. So you may not see results from using expired mass gainers.

The bottom line then is that consuming expired mass gainers is a bad idea. It is likely to cause you problems and can make you seriously ill. It’s also unlikely to even work if it has expired.

In Summary

A mass gainer is, fortunately, a product with a decent shelf life – as far as supplements are concerned. 

If you are using a supplement that can go clumpy or can lose potency when expired like pre-workout then you need to be much more careful about storage and usage.  

Mass gainers will expire and some active ingredients can go bad depending on the particular brand or ingredient used. 

Most mass gainers will have a shelf life of around 2 years from the point of purchase so provided you store them in an airtight container and keep them at a cool temperate away from direct sunlight or moisture then a mass gainer should last right up until its expiry date. 

If a mass gainer has expired though, we’d recommend against using it as it’s likely to lead to an upset stomach or illness so it’s worth monthly checking the smell and texture of your mass gainer just to ensure it’s not expired prematurely.