Vitamin D supps might have shelf life as low as 2 weeks after opening?

[BearWithMe]

This guy suggests that after you open a bottle with vitamin D supplement, you have just about 2 weeks to consume it before it completely loses its potency. Because when you open the bottle, oxygen gets in and can begin the decay process of the vitamin D into inactive metabolites.

I haven't found any research on this, What are your experiences? Is that true?

 

[Perry Staltic]

Sounds like BS

 

[souperhuman]

I think this is true to some extent. The gel capsules I take are very hard upon first opening a bottle, but after a while they become softer and softer being exposed to the moisture in the air, One time, I noticed that taking these softer gels caused me some stomach discomfort, and I switched to a new bottle. The new bottle did not cause any discomfort. It seems best to use it quickly, and to avoid putting your fingers in the bottle to prevent moisture contact.

 

[BearWithMe]

I have bought a bottle that is supposed to last a year. Recently I have finished it and opened a new one. The difference was very obvious.

Then I started researching and there is quite a lot of anecdotal evidence of this, even in the reviews of various products with many pills in one bottle.

 

[Perry Staltic]

I would think that if there is anything to this it would be well known and manufacturers would adjust by adding stabilizers, which is probably what they do. The guy in the OP admits that he is merely speculating based on his limited knowledge. He may know that vitamin D oxidizes very quickly, but he seems to know nothing of manufacturing actualities.

 

[BearWithMe]

The toxicity of various additives, flow agents, fillers, binders and artificial colors is well known, and manufacturers generally don't give a flying f**k.

I can imagine there is no desire to find a truth about this. It would increase manufacturing costs and decrease value of the products.

 

[Makrosky]

Hmmm but that is for liquid versions right? Capsules and the like shouldn't be affected.

 

[nerfherder]

In my experience Vitamin D loses potency in this way but the timing varies. Thorne went away from a regular dropper built in to the cap to a slow tiny hole dropper fixed to the bottle that lets the bare minimum of air in and when I first saw it I figured it was to increase shelf life. Even so, it loses its effect on me after 2-4 weeks. Other brands are similar.

I can tell pretty quick - my migraines come back and then they go away when I switch to a new bottle. If I go cold turkey with no Vit D it takes a couple of days for the migraines to appear (unless I get plenty of sun) so it isn't like I had built up a couple of weeks of stores in my body.

 

[CastorTroy]

So would it be the same with vitamin K2?