Debugging Life: Do omega-3 need to be refrigerated?

Your first, great, step was to start taking care of yourself, buying some good source of Omega-3 and starting taking it in the right way.

In the case you know nothing about fish oil read this.

The second step you have to know and follow is to learn how to store it, whether you are using capsules or the oil version.

A thing that may happen, if you badly store your stocks, is oxidation.

You should avoid that.



Put simple, oxidation is the loss of an electron by an atom or a compound. It leads to a change in its properties.

Think at iron and his reddish antagonist, rust, which is iron oxide.

It’s a normal process in fats and oil with unsaturated fatty acids (in this case EPA and DHA), and we can find oxygen to be guilty. His partners in crime are heat and exposure to light.

The negative effects of oxidised omega-3s are not fully researched, but I try to empty my stores before oxidation strikes.

That’s because you can see by yourself the effects, such as a rancid smell of bad fish or your capsules becoming softer and softer.

Mind the label and the package

You should always read the label and be informed on what you are feeding your body with: food, supplements, cosmetics, etc.…

You can’t trust the deceiving marketing info found on the front of products.

This little deviation is only to say to avoid fish oils that claim to not require to be put under refrigeration.

Like said before, heat is among the factors leading to oxidation. So, the magic used to make the fish oil immune to heat is something you wouldn’t introduce in your diet.

What’s the other factor? Yes, light.

Avoid packages that don’t protect from light and go for dark bottles.

A good thing is to search for products with antioxidants added, like Vitamin E and green tea catechins.


Oxidation starts to operate as soon as you open the package. Until then you can keep your supplements at room temperature, watching out for the expiration date.

In addition, if is the container is not dark, watch out for light exposure.

I prefer to do not buy an excessive quantity of capsules, just enough for three or four months. That is because I tend often to anticipate the expiration date of products, and even good fish oil supplements aren’t expensive.

Once opened, store your omega-3s in the fridge, to slow the oxidation due to temperature.

Calculate 90 or 120 days from the moment you opened it and write the date on the package. After that date you need new fish oil.

Capsules vs liquid oils

The main difference between the two are the barrier in capsules used to encapsulate the fish oil. You can see it as a defence from oxygen, helping delaying the oxidation.

This means that the liquid oils, once opened, are directly exposed to air, and so they will go rancid much faster than capsules.

While capsules help in prevent oxidation, and you could conserve them at room temperature, I still prefer to follow the safe way and put them in the fridge.

Has it gone bad?

If you were a scientist, equipped with a super cool lab, then you probably would not be reading this guide.

For all of us, mere mortals, there are simple things that can reveal to us if the time to throw the supplement out of the window has come.

Obviously, I am just joking, do not throw the golden pills out of the window. Heat them in the oven and send them to your boss.

Yeah, yeah, I am joking.


Back to reality, take one of your capsules and cut it with a knife or scissors. Pay attention to the liquid inside and do not stain your freshly painted portrait.

Now, smell.

If it seems like a dead fish swimming in your kitchen since last Christmas, then it’s gone. To your boss!

Alternatively, you can put a capsule in the freezer, wait some time, and then cut it. If the oil is still good, it should not be frozen.