Research says fish oil supplements do not appear to improve ADHD symptoms. But there may be other benefits.

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If you’re living with attention deficit hyperactivity disorder (ADHD), you might be looking for natural or alternative treatments to complement your current treatment regimen.

About 7% of children and 3% of adults worldwide have ADHD. Some common symptoms of this condition include inattention, hyperactivity, and impulsivity.

Typically, treatment for ADHD includes a combination of medication and therapy, along with certain lifestyle changes. However, researchers have also spent several decades looking into nutritional supplements that may benefit ADHD.

Until recently, scientists have thought that omega-3 fatty acids were a promising supplement that might help reduce ADHD symptoms. However, recent research has shown they don’t appear to be effective for this purpose — though they may be beneficial in many other ways.

Omega-3 fatty acids are a type of fat called polyunsaturated fatty acid (PUFA) that’s important for the brain and the body.

Researchers believe that this PUFA can improve cognitive function and offer other benefits. The best sources of omega-3s are fatty fish and fish oil supplements.

On the other hand, scientists believe an imbalance of omega-3s and omega-6s (other PUFAs) may increase the risk of many chronic health conditions.

For example, research has shown that people who consume a Western diet tend to consume about 20 times more omega-6s than omega-3s. This has been linked to an increase in obesity.

Recent research has concluded that taking fish oil shows little to no positive effect on ADHD symptoms.

However, you may have heard the opposite. That’s because in the past, several studies suggested that fish oil could be beneficial for ADHD. However, more recent research has shown otherwise.

To understand why opinions have changed, it may help to understand how this idea originally came about.

What scientists used to think about ADHD and fish oil

Researchers initially began to wonder if fish oil would help people with ADHD based on several different research findings, such as:

  • The front part of your brain, called the prefrontal cortex, which is responsible for your thoughts and behaviors, is immature or inflamed in people with ADHD.
  • People with ADHD may have lower levels of omega-3 and omega-6 fatty acids than those without ADHD.
  • A 2005 study of children with developmental coordination disorder (DCD) concluded that, over a 3-month period, children who took omega-3 and omega-6 supplements showed improvements in reading, spelling, and behavior.

Based on those research findings, scientists hypothesized that:

  • Because omega-3 supplements may reduce inflammation, and some people with ADHD have an inflamed prefrontal cortex, then omega-3 supplements might reduce the inflammation and therefore reduce symptoms.
  • The omega-3 deficiency in people with ADHD could cause or enhance symptoms. So, increasing the omega-3 levels of someone with ADHD could possibly reduce their symptoms.
  • If children with DCD showed improvements in reading, spelling, and behavior when they took omega-3s, then perhaps the supplement could also improve the behavior of children with ADHD.

In 2012, one study looked into whether omega-3s would benefit children with ADHD in the same way it benefited those with DCD.

For this study, researchers used algae oil, which contains omega-3s and is an algae-based substitute for fish oil. They concluded that taking omega-3s did improve reading and ADHD-like behavioral symptoms.

A 2014 study found that parents and teachers believed that taking omega-3 supplements improved the symptoms of hyperactivity. Parents also said that omega-3 also improved their child’s ability to focus, but the teachers didn’t agree.

What newer findings say

As scientists did more studies, they disproved the initial results that suggested fish oil might help with ADHD. For example, a 2017 study of children ages 6 to 15 years old with mild ADHD symptoms found the children experienced no beneficial effects when they took omega-3 supplements.

In 2018, researchers took a second look at whether omega-3 could improve reading, working memory, and behavior. In this study, researchers provided the children with fish oil supplements.

The children, who were in the bottom quarter of ability in reading, were tested before and after by both their parents and their teachers. The results showed no improvement in reading or working memory and only a very slight improvement in behavior.

Because of this conflicting research, researchers have also conducted several literature reviews on this topic —meaning they’ve reviewed and combined the results of numerous previous studies.

In 2019, a group of researchers reviewed 126 studies published between 1980 and 2019 regarding the use of PUFAs to treat a variety of conditions. They found that omega-3s were most beneficial for people with major depressive disorders or bipolar disorder.

There were only “small to modest” benefits in people with ADHD.

A 2021 review of 31 high-quality studies found that taking PUFAs had no effect on ADHD symptoms.

The researchers concluded that there was no evidence that taking PUFAs provided benefits for those with ADHD. However, they said the evidence wasn’t certain and they couldn’t offer conclusive guidance based on their findings.

Since the research has found that taking fish oil doesn’t seem to help with ADHD, there’s no established dosage that healthcare professionals recommend for people with this condition.

However, if you’re considering taking omega-3s anyway, follow the recommended dosage on the label.

It’s a good idea to find out how much docosahexaenoic acid (DHA) and eicosapentaenoic acid (EPA) a particular type of supplement contains per serving — the bottle should say this. DHA and EPA are two main types of omega-3s in fish oil.

European Food Safety Authority recommendations from 2012 suggest getting a Reference Daily Intake (RDI) of 250 to 500 milligrams of EPA and DHA combined.

If you do want to try omega-3s to see if they improve your ADHD symptoms, they’re generally safe for children and adults. However, many people find that these supplements tend to have an unpleasant fish taste and cause bad breath.

Although most side effects are minimal, they may include:

It’s also possible that taking omega-3 supplements may cause problems with certain medications that affect blood clotting. If you have a health condition, consider speaking with a healthcare professional about whether it’s safe for you to take them.

If you have a seafood allergy, researchers don’t fully know whether you can safely take a fish oil supplement.

While some studies have shown that fish oil may reduce hyperactivity in people with ADHD, overall the research has found that fish oil has very minimal, if any, real benefits in people with the condition.

However, if you’re interested in trying a fish oil supplement, there are a variety of fish oil supplements available in both pill and liquid form.

If you have any other health conditions or take prescription medications, it’s always best to check with a doctor before adding fish oil to your daily routine.

You can read more here about popular fish oil supplements.