I have a giant bottle of good ol' Costco brand multivitamins and the bottle is marked with:

"Freshness and potency guaranteed through: July 07"

Does the potency actually decrease over time? They seem 'fresh' enough to me but I want to make sure that they're actually worth taking.


Also, same question for fish oil pills if you know that answer, too.

Thanks!!

Probably... some ingredients degrade with air contact, others with light. The actual amounts are somewhat difficult to tell, but I'd go ahead and use them. Better than not taking any...

Heat would also have negative effects on degrading. . .especially with whey protein (You do not want to put it on top of your fridge if it is too hot).

If you leave spices out in the open. . .the light will have a negative impact on their quality over time. Same with olive oil. . .

I have been told it is perfectly fine to take supplements two months after they expire, I don't really know about a full year. . .Did you buy the expired bottle or find it recently?

Heat would also have negative effects on degrading. . .especially with whey protein (You do not want to put it on top of your fridge if it is too hot).


I'm curious as to where you gather your information from.

A Biochemistry book (heat denatures proteins) and then an inference (some fridges generate excess heat which may come out on the top; older models I suppose).

:madpimp:

I personally keep my whey on my fridge right now because we have our house fairly cool and our fridge is not too bad with excess heat.

A Biochemistry book (heat denatures proteins) and then an inference (some fridges generate excess heat which may come out on the top; older models I suppose).


Please referrence me to this biochemistry book.

As long as the protein is not in solution denaturation will not take place, especially from heat.

You denature meats when you cook them, but it doesn't render the amino acids useless. However we are speaking about different molecular structures here.

If your tub of protein is properly sealed/closed, and not exposed to excessive moisture (ie, top left open) your protein powder is good to go.

Biochemistry by Berg, et al. 2007. Sixth edition.

I am not going to quote this book as I prefer google for ease of access to information and time saving.

I do not really disagree with what you are saying mastover. Here are two additional links I just pulled up.

1. http://www.elmhurst.edu/~chm/vchembook/568denaturation.html (more legit)

2. http://forum.bodybuilding.com/archive/index.php?t-613365.html (as legit as your average bodybuilding forum)

Some key points from 1
Heat can be used to disrupt hydrogen bonds and non-polar hydrophobic interactions. This occurs because heat increases the kinetic energy and causes the molecules to vibrate so rapidly and violently that the bonds are disrupted. The proteins in eggs denature and coagulate during cooking. Other foods are cooked to denature the proteins to make it easier for enzymes to digest them. Medical supplies and instruments are sterilized by heating to denature proteins in bacteria and thus destroy the bacteria.


Some key points from 2
Milk properties/proteins are heat sensitive, particularly at temperatures above 70 C/158 F, so if you want to add them to your oats or other hot foods do it right before eating them. You can also use any No-Bake recipe you like, just add in the protein powder amount you desire, for example:

No, it will not destroy the whey protein. Denaturing means that the structure of the whey starts to unfold (breaking of weak bonds within the structure). Because of this, it will be less biologically active, but probably the most noticable effect is that it becomes much more 'stiff.' Whenever I try cooking with it, I can certainly tell the difference in texture. However, the protein itself is not destroyed - if you put in 30g of protein, you get 30g out.

Cooking at a lower temperature may help reduce the effects of the denaturing, but whey protein is not very stable on it's own, and will denature quickly. I'd be more concerned with the texture of your baking, rather than the effects of heating whey.


So, I believe we can agree that keeping your whey sealed and without excessive moisture are both good ideas lol. We can also agree that heat in general is less than ideal. Denaturing may make the amino acids in proteins more easily digestive, but I would think a constant heat source near the whey when it is in storage is less than ideal.

I went home today and touched the top of my fridge. I did not feel any noticeable heat. I want to say with some older model fridges (or ones that are particularly inefficient) this was more of an issue.

So keeping your whey on top of the fridge is probably not going to do much of anything to your whey. . .unless you have a particularly ineffective fridge. In extreme situations (heating oatmeal, you may want to add the whey after if you are looking at being as efficient as possible).

BUT, no I agree heating whey is probably not going to have a significant effect on the whey (unless we're talking sitting outside in 100 degree weather).

What about Vitamin C. Say....it was supposed to be taken before July '96....but it was still sealed this week when my grandma found it...would that be a problem?

Where are you getting all of this expired vitamins? :lol:

I highly suggest you go ask a Pharmacist at any respectable grocery story.

The vitamins will lose some of their potency. . .with certain products (creatine), the creatine will actually true into urea. High levels of urea in the blood is highly toxic. The chances of moisture contaminating the product while in storage could also be a factor. . .

I am just a student though, so honestly I think you are better off bringing the vitamins in and showing the container to an expert.

So, I believe we can agree that keeping your whey sealed and without excessive moisture are both good ideas lol. We can also agree that heat in general is less than ideal. Denaturing may make the amino acids in proteins more easily digestive, but I would think a constant heat source near the whey when it is in storage is less than ideal.

I went home today and touched the top of my fridge. I did not feel any noticeable heat. I want to say with some older model fridges (or ones that are particularly inefficient) this was more of an issue.

So keeping your whey on top of the fridge is probably not going to do much of anything to your whey. . .unless you have a particularly ineffective fridge. In extreme situations (heating oatmeal, you may want to add the whey after if you are looking at being as efficient as possible).

BUT, no I agree heating whey is probably not going to have a significant effect on the whey (unless we're talking sitting outside in 100 degree weather).

In solid phase, proteins will be very resilient to denaturation. In solution, however, the bonds that construct the three-dimensional structure (non-covalent bonds) can be disrupted by temperature change.

You could leave a jar of protein in the trunk of your car for days even if the temperature was a sweltering 100+ degrees. As long as the tub is sealed (preventing extra moisture) the protein should be more than adequate.

In solid phase, proteins will be very resilient to denaturation. In solution, however, the bonds that construct the three-dimensional structure (non-covalent bonds) can be disrupted by temperature change.

You could leave a jar of protein in the trunk of your car for days even if the temperature was a sweltering 100+ degrees. As long as the tub is sealed (preventing extra moisture) the protein should be more than adequate.

As far as I know this is correct.

Plus, everyone keep in mind that the whole point of stomach acid is to denature the bejeesus out of most proteins. So unless you inject your proteins, denaturation is not really that big a deal for bioavailability.

The game in the stomach is that the acid denatures the proteins so that enzymes like pepsin can chop the protein down to amino acids. The plan of digestion is to crack the protein down to aminos in most cases, which is why cooking doesn't reduce the nutritional value of protein. In fact, because cooking reduces the amount of energy the body has to use to digest meat, cooking actually increases the nutritional value of meat. (Vegetables are a little different story because they have a lot of interesting small molecules, but as far as proteins go it's the same.)

As far as I know this is correct.


Thank You Sir!! You have no idea what your post means to me! :)

Thank You Sir!! You have no idea what your post means to me! :)

:lol:

Well you're the nutrition maven.

That's actually really cool the manufacturer's use such high quality plastic. :lol:

:tucool:q

Its not that I'm 'finding' them.....I was just talking to my grandma about Vitamins, and she mentioned that she had a left-over bottle of Vitamin C that was supposed to expire in '96.

So I figured I'd use them up. ;)