Omega 3 side effects you should know about

And what are the benefits of omega 3 and fish oil?

Are there any fish oil side effects? What about Omega-3 side effects? Are those two the same?

Great that you’re doing your research, because indeed, you do need to be aware of the side effects of omega 3, or more correctly: the side effects of fish oil. Fish oil certainly has an impact on certain health conditions.

By your landing on this page, I expect you’re already aware that there are good and bad fats. But you may ask yourself why I, as a couples counsellor, would want to talk about that.

Well, if your body is starved of essential nutrients then it’s under stress. A stressed body equals a stressed mind – even if you’re not always aware of it. Stress has huge consequences for your physical, mental, emotional and social well-being.

And, of course, the health of your relationship is linked to all of these. Everything that you do to nurture yourself will directly – and indirectly – benefit your relationship too.

Omega 3 softgels

What is omega 3?

Omega-3 is an essential unsaturated fatty acid. ‘Essential’ here means that your body cannot produce (synthesise) it by itself – so it has to come from your food.

Fats make up 60% of your brain, in the same way that water makes up 80% of your body. Without water, we die. Without the right fats, your brain at the very least fails to function at its optimum level.

Just in case you’re still asking yourself: “If that’s so, then why are the fats in my potato chips, biscuits, cakes etc. so bad? Why doesn’t my body/brain benefit from those?”

The simple answer is that there are no beneficial fats in those foods. (Actually, I’m afraid to say that their only ‘benefit’ is a very temporary feeling of satisfaction!)

The dangers of trans-fats


Your cakes, biscuits, pastries and takeaways (or take-outs) are very likely to contain trans-fats (Google it!). The chemical structure of these fats is at odds with what your body expects and desperately needs.

In the absence of healthy fats, your body will use trans-fats ‘building blocks’ in your brain. However, your brain has to work much harder to process these. The chemical structure of these fats is incompatible with your body’s requirements.

So, your brain’s energy expenditure increases to overcome the disadvantage of working of with poor quality, wrongly-shaped materials. This means your brain’s ability to function and communicate effectively is compromised.

Nerve cells in your brain communicate by way of neurotransmitters. These are the chemical ‘messengers’ that convey ‘messages’ from one nerve cell to another.  Have a look at this video to see them at work…

Nutrients provide the fuel for the fire in the nerve cells. But they have difficulty passing the membrane (the mesh covering the nerve cell) if it’s constructed from poor quality (trans) fats.  

Trans-fats therefore make it difficult for your neurons to branch out and lay the road necessary for the transport of messages.

In addition, trans-fats decrease the flow of blood and oxygen to your brain. Is it any wonder that when you’re deficient in Omega-3, you’re missing out on all of its benefits? And this puts you at risk not only of depression, but a plethora of other problems too.

The benefits of Omega-3
– 5 generally accepted results

Omega-3 is the subject of numerous studies. Since our understanding of how the body works is improving all the time, it helps to keep an eye on developments.

Here are some of the generally recognised Omega-3 benefits:

  1. It can lower the risk of cardiovascular disease – fish oil is very beneficial for the health of your heart.
  2. It can lower the risk of cancer.
  3. It can lower the risk of arthritis.
  4. It can improve brain function: cognitive (memory and performance) and behavioural processes. This is of course of huge importance with regards to your mental and emotional well-being. However, actually boosting omega-3 in your brain appears to be difficult [1].
  5. It can reduce inflammation (interestingly, inflammation has now also been linked with depression).

Fish oil (omega 3) side effects

If you decide to take fish oil then be do be aware of the following omega 3 side effects (or more correctly the effects of fish oil).

Those side effects depend on:

  • whether you’re suffering from diabetes, heart disease, bleeding disorder and/or have concerns over your cholesterol levels;
  • certain medication you may be taking;
  • the source of your fish oil;
  • the fish oil product you choose;
  • the dosage (if you are taking blood thinning medication).

Diabetes, heart disease and fish oil side effects

If you’re taking any medication, be sure to speak to your healthcare provider before taking any fish oil supplements.

Your doctor is likely to tell you that there are no Omega-3 side effects as such.

However, you may need to adjust your medication. Your doctor may want you to have some extra blood tests done to make sure that values remain stable (although actually, they’re likely to improve!).

What are the omega 3 side effects when you’re taking blood-thinning medication (anticoagulants)?

Any medication – blood-thinner or otherwise – has a benefit / risk ratio.

Do you have a bleeding disorder and are you wondering about the omega 3 side effects (fish oil side effects)?

Are you taking anticoagulants?

Then you absolutely should consult a doctor before trying fish oil, especially if you want to take a higher dosage. You could easily be taking too much!

Fish oil stops platelets clumping together, hence its ‘blood-thinning’ effect. If your doctor has no qualms about fish oil he or she would be happy for you to get all the supposed health benefits of that rather than risk the side effects of the available drugs. You will need advice on the right dose of fish oil for you to prevent any side effects.

Other side effects of fish oil

The source of your Omega-3 is really important.

For example, if you start taking pure fish oil there is chance you’ll notice the following side effects:

  • minor belching – hardly a terrible side effect of fish oil!
  • nausea,
  • loose stools – you may feel that is a benefit,
  • bloating,
  • See also: drug interaction – further down.

So, at least be sure that you choose a quality product.

A badly fishy back burp is not a good sign: fish oil is a fat. Like butter, if it’s treated badly or it’s old it becomes rancid – not healthy (or nice) at all. The manner in which the oil is extracted, purified and packaged is extremely important.

Remember too that many companies mask bad taste and smell from bad products by adding chemical additives and perfumes.

Omega 3 side effects: the problem with vitamin A

Make sure that you don’t mistake the dosage of fish liver oil (e.g cod liver oil) for that of omega 3, because it’s very possible for you to overdose on vitamin A or D if you take the quantities advised for fish oil. Both of these vitamins are naturally part of the product or are routinely added to fish liver oils (if previously removed by processing).

The dosage of fish oil you’re recommended to take is too high if you were to use a liver oil, such as cod liver oil.

New studies show that modern processed cod liver oil may even raise death rates. In developed countries people normally don’t have a Vitamin A deficiency, rather more likely a Vitamin A toxicity according to Dr Mercola.

Safe products

Fish was traditionally fermented to preserve it and thereby maintain it’s health-giving benefits.

The Weston A Price Foundation (a non-profit nutrition education foundation) recommends:

Blue Ice High-Vitamin Fermented Cod Liver Oil
Green Pasture Cod Live Oil

Garden of Life Olde World Icelandic Cod Liver Oil (also available from Live Superfoods)

Photo: Salmon with lemon and chives - omega 3 or fish oil benefits
Rose colored fish steak, summer food with wine and lemon marinade macro closeup

Fish oil and pollution

It’s important to state that certain side effects from fish oil depend on the quality and source of the fish (oil). Many people start out trying to add Omega-3s by eating more fish.

Unfortunately, fish is now heavily polluted with methylmercury, polychlorinated biphenyls (pcb) and dioxins. These toxins for sure are detrimental to your health.

Drug interactions?

Fish oil can apparently help prevent or reduce the severity of side effects of Cyclosporin (a drug used to suppress the immune system) and help statins (a class of drugs used to reduce high levels of ‘bad’ cholesterol) to be more effective, due to their anti-inflammatory effect.

How much Omega-3 do I need to get the benefits?

The average American adult gets less than 1g of Omega 3 fatty acids per day. However, the recommended daily amount, especially for people who are suffering from depression, is reported to be somewhere between 2-4g.  Be sure to also read my article on fish oil and depression and consult your healthcare provider.

Some doctors even recommend higher doses. (I’m getting a mental image of you turning up your nose at the thought of spoonfuls of oil and huge capsules!)

Foods high in omega 3 are always the best sources!

Omega 3 fatty acids and fish

Omega-3 consists of two primary – and very important – fatty acids. Take a deep breath before you read this: one is eicosapentaenoic acid (EPA) and the other is docosahexaenoic acid (DHA). EPA is especially beneficial for depression.

I know… I can’t pronounce the full names either – let alone remember them!

  • EPA – found almost exclusively in cold-water seafood
  • DHA  – found almost exclusively in cold-water fish, although not farmed fish, unless they were fed Omega-3 rich food (DHA is particularly beneficial for the membranes of your nerve cells)

Here is a list of fish with omega 3 to help you shop:

  • mackerel
  • salmon
  • albacore tuna
  • anchovies
  • lake trout
  • sardines
  • white fish
  • cod liver oil

ALA (also an important fat) is found in plant sources. (Note: The conversion from ALA to DHA varies between individuals, therefore eating fish or fish oils is essential!)

Here are some more omega 3 sources…

It doesn’t always need to be fish

Other foods high in omega 3 (and suitable for vegetarians and vegans)

  • walnuts
  • flax seeds
  • chia seeds beans
  • olive oil
  • winter squash
  • tofu (there can be problems with eating tofu though; see

If you want to beat depression, for example, choose the right foods that contain Omega 3. It beats taking antidepressants with their multiple side-effects and potential damage to your brain – if they work at all.

Remember: your personal wellbeing contributes to the health of your relationship!

Are you vegetarian?

It is said that the supposed benefits of Omega-3 lie in its conversion to DHA and EPA.  Many people don’t have the chemical needed to convert fish oil into those substances. Flax seed oil may therefore not have the reported benefits gained from fish oil.  However, I noted the following in an article on Dr Mercola’s website:

“It is thought that the conversion of the plant-based ALA into the fish-oil based eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) is not that efficient,” he says, “But we find that our vegetarian patients actually do it very well and don’t use the fish oil or animal-based omega-3 fatty acids as effectively.”  

-Dr Nicholas Gonzales

In addition Dr Mercola reports on flax-seed oil that it increases prostate cancer, whilst fish oil apparently decreases it.

Does Omega-3 help depression?

In Greenland, Eskimos consume 7-10g per day of long-chain Omega-3s (DHA and EPA) and know virtually no depression. (Or at least, those who have been able to hold on to their traditional life-style of course).

Yet Eskimos spend much of their waking time in the dark with little exposure to sunlight.

Why is that significant?

Well, you yourself may well be aware of how much better you feel in the summer than in the winter. For more on this, have a look at my article on fish oil and depression. The right food can really help you if you’re suffering from depression.

Would you benefit from Omega-3 supplements?

Many people simply don’t like the taste of fish. Others have, understandably, avoided both fish and fish oil because of an allergy. Some are worried about toxins in fish such as mercury, lead and PCBs.

Perhaps you’re taking omega-3 supplements, like many other health conscious individuals, or perhaps you’re thinking about doing so.

At the very least, try to avoid the cheapest stuff on the market. Some fish oils have been extracted by chemical or mechanical means. It may have been heated or otherwise spoiled.


Do your research carefully – there are plenty of good quality omega-3 supplements available. But always remember: the key is a healthy, balanced diet – so never rely on supplements to the exclusion of a variety of foods that naturally contain the nutrients you need.

Other helpful links

Marine Conservation Society
Weston A Price Foundation


[1]“Technique Boosts Omega 3 Fatty Acid Levels in Brain.” UIC Forms Partnership with Central Intelligence Agency | UIC Today, Accessed 25 Feb. 2019.

*) “Get in Your Best Shape Ever in 2014!” Harvard Health Blog RSS. N.p., 17 June 2013. Web. 12 Feb. 2014.

Other resources

“There’s Something Fishy Going on.” What Doctors Don’t Tell You. N.p., n.d. Web. 18 July 2018.

“Fish Oil Supplements for a Healthy Heart ‘nonsense’.” BBC News. BBC, 18 July 2018. Web. 18 July 2018.

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