Fish Oil for a Cough

Fish oil could help with cough, depending on the underlying cause. Because of powerful anti-inflammatory properties that come from its omega-3 fatty acids, docosahexaenoic acid and eicosapentaenoic acid, fish oil has a variety of health benefits. Fish oil can be taken as a dietary supplement or by consuming fatty fish such as salmon, herring, cod liver, tuna and mackerel.

Causes of cough

Before taking fish oil supplements or relying on food to cure a cough, it's important to know the underlying cause. Reasons for coughing might include tobacco smoking; asthma; sinusitis and post-nasal drip; virus; bacterial infection; chronic obstructive pulmonary disease, or COPD; heart disease; or cancer. According to MayoClinic.com, a chronic cough is one that persists for eight weeks or more, and should be investigated for cause by a health-care provider.

Fish oil and Asthma

According to the National Institutes of Health, fish oil might be beneficial for asthma because it improves air exchange in the lungs. The effect is primarily seen in children, versus adults. Indiana University researchers found that 3.2 grams of eicosapentaenoic acid, or EPA, and 2 grams of docosahexaenoic acid, or DHA, a day was able to help patients with asthma reduce the need for medications post-exercise when asthma symptoms are more likely to occur.

Airway Inflammation

Researchers from Division of Epidemiology, School of Public Health, and Department of Laboratory Medicine and Pathology, University of Minnesota, Minneapolis, Minnesota; and H. Lee Moffitt Cancer Center and Research Institute, Tampa, Florida studied DHA in fish oil's effect on chronic obstructive pulmonary disease. From the research, conducted in animals, the authors concluded that omega-3 fatty acids might treat inflammatory types of respiratory ailments. Viruses, environmental pollution and bacteria that can lead to cough all produce inflammation in the lungs.

Immune Function

In a study of trauma patients, researchers from China gave intravenous fish oil to trauma patients. They compared immune function biomarkers in the bloodstream to a group of patients given soybean oil. The patients given omega-3 fatty acids had a significant boost in immune response to help fight infection. The trial results showed fish oil enhanced immunity at a cellular level.

Expert Advice

The National Institutes of Health cautions fish oil can be taken safely up to 3 g/day, or 3,000 mg. Higher doses can increase risk of bleeding. There are questions about the safety of fish oil supplementation during pregnancy, though fish oil is considered "likely safe" at the recommended dose. Taking large doses can also lower immune function, increasing susceptibility to cough, flu and other infections. Before using fish oil to treat cough or any illness, speak with your health-care provider about individual risks and benefits.