Can Taking Fish Oil Help Reduce Anxiety?

Anxiety affects about one in five adults in the United States, making it one of the most common mental health conditions, according to the National Alliance on Mental Illness. Although therapy and medication can help treat anxiety, researchers are looking for alternative approaches to help reduce anxiety, such as fish oil.

Fish oil has omega-3 fatty acids, which are essential nutrients that your body can't produce on its own. Therefore, you must get your omega-3s from food like nuts, seeds, or oily fish such as tuna, herring, and trout. Fish oil has two types–docosahexaenoic acid (DHA) and eicosapentaenoic acid (EPA). According to PsychCentral, DHA helps fuel the brain and make necessary connections. Without it, you could have problems with memory, learning, and anxiety. A 2014 review in the Journal of Pharmacological Sciences found that diets low in omega-3 fatty acids are linked to the onset of dementia, schizophrenia, posttraumatic stress disorder, and depression.

A 2013 study in the Journal of Clinical Psychiatry studied EPA and DHA levels in people with major depressive disorder and depression with anxiety. Compared with healthy people, people with major depressive disorder had lower DHA and EPA levels. People who had depression with comorbid anxiety had lower DHA and EPA levels than people with depression. The severity of their anxiety symptoms was linked to their DHA and EPA levels.

To test the effect of omega-3 supplements on anxiety, a 2011 study in Brain, Behavior, and Immunity gave medical students either an omega-3 supplement or a placebo for 12 weeks. The omega-3 group experienced reduced inflammation and anxiety compared to the controls.

On the other hand, a 2022 study in Frontiers in Nutrition looked at the effect of omega-3 fatty acids on people diagnosed with depression. One group took 2.4 grams a day of omega-3s and another group took venlafaxine (used to treat depression and anxiety) for 12 weeks. The group that took the omega-3s saw their anxiety symptoms ease for the first four weeks, but the effect didn't endure after 12 weeks.

A 2018 systematic review and meta-analysis in JAMA Network Open examined 19 clinical trials that included 2,240 people in 11 countries. It found that particularly in clinical populations, taking 2,000 milligrams or more of omega-3 fatty acids reduced symptoms of anxiety. Supplements that had less than 60% EPA had more of an effect on anxiety than those supplements that had a higher ratio of EPA. This runs counter to the depression research, which shows that the EPA ratio should be at least 50% or 60% to reduce depression. The study said that more research is needed to look at the specific ratio of omega-3 fatty acids to help with anxiety.

A 2015 review in Clinical Psychopharmacology and Neuroscience offered some possibilities of why omega-3 fatty acids can improve mental health. Omega-3s could increase neurotransmitters in the brain to ease anxiety and depression. Their anti-inflammatory and antioxidant properties could decrease the oxidative stress in the brain that causes psychological conditions. Omega-3s could also promote neuroplasticity, which helps in rewiring the brain.

According to PsychCentral, you can incorporate more seafood in your diet to get your omega-3 fatty acids. However, if you take a fish oil supplement, be sure to take it with food to help with absorption. You can also split your fish oil supplement and take it twice a day to avoid acid reflux. Be sure not to take too much fish oil, because taking more than 900 mg of EPA and 600 mg of DHA daily over time can negatively affect your immune function. Taking 4,000 mg of fish oil a day increases your risk of atrial fibrillation.

If you decide to try taking fish oil to see if it helps ease your anxiety, be aware that not all people respond to supplements in the same way. In some cases, the supplement might have the opposite effect. A 2015 case study in Oxford Medical Case Reports described a man whose anxiety worsened while taking fish oil supplements. He also suffered from insomnia and panic attacks. When he stopped taking the supplements, his insomnia and anxiety disappeared.