Fish oil is one of the first things many people reach for when they feel run down. If you have wondered about fish oil for fatigue, here is what omega-3s are, what the research does and does not show, where to find them in food, and when tiredness is worth checking with your GP.
What are omega-3s?
Omega-3s are a family of polyunsaturated fats your body needs but cannot make, so they have to come from your diet. Heart Foundation — Omega-3 and heart health
There are three main types. ALA comes from plant foods such as walnuts, chia seeds and flaxseeds, while EPA and DHA come mainly from fish and seafood. Heart Foundation — Omega-3 and heart health
They play a part in keeping your heart rhythm steady, your blood vessels flexible and inflammation in check. Better Health Channel — Dietary fat
Fish oil supplements are made from fatty fish and contain EPA and DHA. Australian Family Physician — Fish oil
Does fish oil help with fatigue?
The short answer is that research has not shown it does. The main reviews on this question looked at fatigue in people with a long-term illness, such as cancer or multiple sclerosis, rather than in otherwise healthy people who feel worn out.
An Australian-led review of 33 trials in people with cancer found that omega-3 supplements did not clearly reduce fatigue. The small difference it saw could have been chance, and most of the trials had a high or unclear risk of bias. Lam et al., Bond University review (2020)
In multiple sclerosis, a Cochrane review found that the one trial which measured fatigue showed no lasting difference between omega-3s and the comparison treatments, and called the overall evidence uncertain. Cochrane — Dietary interventions for multiple sclerosis
Tiredness also has many possible causes, and the right treatment depends on what is behind it. Healthdirect — Fatigue That is why one supplement is unlikely to be the answer for everyone.
None of this means omega-3s don't matter. They are still part of a healthy, varied diet; they just have not been shown to relieve low energy.
Where can I get omega-3s from food?
The Heart Foundation suggests 2–3 serves of fish a week, fresh or tinned, including oily fish, and says food is enough for most people. Heart Foundation — Omega-3 and heart health
Good everyday sources include:
- oily fish such as Atlantic salmon, mackerel, sardines, trevally and southern bluefin tuna Better Health Channel — Dietary fat
- walnuts, chia seeds and flaxseeds (linseeds) Heart Foundation — Omega-3 and heart health
- canola and soy oils Better Health Channel — Dietary fat
Omega-3s from fish and seafood have the strongest evidence for health benefits. Better Health Channel — Dietary fat
A few easy ways to start: sardines or salmon on wholegrain toast, a handful of walnuts as a snack, or a spoonful of chia seeds on your porridge.
Is fish oil safe with my medicines?
Fish oil can affect how your blood clots. Bruising and minor bleeding are often reported, so it matters if you take warfarin or another blood-thinning medicine. Australian Family Physician — Fish oil
The Heart Foundation advises checking with your doctor before starting any supplement. Heart Foundation — Omega-3 and heart health
When you see your GP about tiredness, they will want to know what medicines and other treatments you take, so mention fish oil and any other supplements. Healthdirect — Fatigue
When to see your GP
See your GP if you have had fatigue for more than two weeks and it is not getting better. Go sooner if it is worrying you, stopping you from doing things, or comes with other symptoms such as weight loss. Healthdirect — Fatigue
Possible causes your GP may look at include:
- anaemia or iron deficiency
- an underactive thyroid or diabetes
- sleep problems such as insomnia or obstructive sleep apnoea
- stress, anxiety or depression
- some medicines
Your body needs iron for muscle strength and energy, and an iron studies blood test is the only reliable way to tell if you are low. See your doctor before taking iron supplements, as too much iron can be harmful. Healthdirect — Iron deficiency
Our posts on thyroid symptoms and your GP conversation and making sense of poor sleep can help you prepare.
Questions you might bring along:
- How long have I felt this tired, and does rest help?
- Could iron, my thyroid or my sleep be part of this?
- Could any of my medicines or supplements be adding to it?
- Is fish oil worth taking for me, or is food enough?
What can we talk about at Melbourne Wellness?
An initial naturopathy consultation includes a detailed health history and a dietary and lifestyle review. We can look at how omega-3 foods might fit into the way you already eat. If anything suggests you need a medical check, we will say so and encourage you to see your GP.
