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Confused about the sea of conflicting information around fish oil’s health benefits? You’re not alone. One minute, it’s hailed as the holy grail for heart and mental health; the next, it’s dismissed as useless. So, what’s the real story about these essential fatty acids primarily found in fish?

Omega-3 fats are important as a supplement for several reasons. First and foremost is their effect on inflammation. Pretty much all chronic disease, including mental health conditions and dementia, is associated with increased inflammation (Giacobbe 2020). And taking omega-3 fatty acids can help to lower it. They work, at least in part, by reigning in an overactive immune system and by reducing inflammatory signaling (Calder 2015).

Other effects of omega-3 fatty acids include their role in supporting healthy cellular communication throughout the brain and nervous system. Omega-3s are crucial for the function of the cell membrane, increasing membrane fluidity. In addition, omega-3 fatty acids affect cellular receptors, enhancing or inhibiting their activity (Bazinet 2014).

Omega-3 Fatty Acids: Preventing Disease and Death

Regardless of the negative press, the benefits of omega-3s may be more powerful than you think. Studies show that they can:

  • Slash your risk of death from any cause by 15-18% (Harris 2021)
  • Protect your heart: fish oil reduced the risk of dying due to heart disease by a whopping 18% (Luo 2024)
  • Help diabetics and cancer patients live longer: Studies show 25% and 19% lower risk of  death respectively with fish oil supplementation (Xie 2023, Wang 2023).
  • Even fight COVID-19: Omega-3s boost survival rates by 24% in severe cases of COVID (Yue 2023)

Forget the naysayers: Anyone claiming fish oil is useless is swimming against the scientific tide.

So how does fish oil compare to statin medications, given that some researchers have advocated adding it to the water supply for the heart-health benefits? A meta-analysis on intensive cholesterol lowering therapy using statins and other standard medications found a reduction in death from heart disease of just 6%. However, deaths from other causes offset this decline so that total mortality was not reduced (Cordero 2023).

It is hard to understand why statin medications are the standard recommendation when you compare their efficacy with fish oil. So why doesn’t fish oil get more love?

Omega-3 Fatty Acids and Atrial Fibrillation

While some research has shown a small potential increase in a heart rhythm problem, atrial fibrillation (Gencer 2021), other studies have found that fish oil can protect from the condition (Qian 2023, Langlois 2017). It’s possible the mixed results have to do with the quality of the fish oil used, as rancid fish oil is known to cause problems. Unfortunately, most clinical trials didn’t test the quality of their fish oil.

Omega-3 Fatty Acids and Mental Health


Beyond fish oil’s benefits in reducing the risk of death, it also has well-documented effects on mental health. Probably the most well-researched is omega-3’s effects on depression. An “umbrella review” of meta-analyses concluded that omega-3 fatty acid supplementation is an effective adjunctive therapy for decreasing depressive symptoms (Lu 2024).

Bipolar Disorder and ADHD

Similar results have been found for treating residual depressive symptoms in patients with bipolar disorder (Kishi 2021). For attention deficit/hyperactivity disorder (ADHD), the latest review of the research found that significant effects were only present in studies that lasted four months or longer, strongly suggesting the need for patience and consistency when supplementing fish oil (Liu 2023).


For schizophrenia, omega-3s also appear to hold promise. A meta-analysis from 2021 found that omega-3s were helpful for both general mental health and positive symptoms in schizophrenia patients (Goh 2021). For those with more severe symptoms, doses of eicosatetraenoic acid (EPA) greater than one gram daily provided significant improvements. Side effects were minimal, and fish oil was well tolerated.

A recent clinical trial even found benefits for schizotypal personality disorder, a common precursor to schizophrenia, in children (Raine 2024). In the study, children were given three months of omega-3 fatty acids or placebo, with or without talk therapy. Children who received fish oil improved significantly more than those who did not. Astonishingly, benefits from omega-3 fatty acids were still present in children nine months after treatment, showing a remarkable long-term effect even with short-term fish oil supplementation.


Data on dementia and fish oil even shows significant potential. Research suggests that higher doses of EPA between 1.5 and 2 grams per day combined with antioxidants improves cognition in dementia patients (Tseng 2023).


Fish oil has well-documented benefits for reducing the risk of death from numerous causes. In addition, omega-3 fatty acids from fish oil also support mental health and brain function, decreasing symptoms of depression, bipolar disorder, schizophrenia, and dementia. Supplementing a quality fish oil is well worth considering for patients looking for a simple approach to improve their health.

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