Diets Higher in Omega-3 Fatty Acids Reduce Headache Frequency and Severity in People With Frequent Migraines

Sixteen weeks of treatment with diets higher in omega-3 fatty acids from fatty fish reduced the frequency and severity of headaches in people with frequent migraines, according to a study funded by the National Center for Complementary and Integrative Health, part of the National Institutes of Health, and conducted at the University of North Carolina at Chapel Hill. The study, which was partially supported by the National Institute on Aging and the National Institute on Alcohol Abuse and Alcoholism, was published in the BMJ. 

The types of fatty acids that people get from food may play a role in promoting or preventing migraine. Modern industrialized diets tend to be low in the omega-3 fatty acids eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA), which are found in seafood, and high in the omega-6 fatty acid linoleic acid, which is found in vegetable oils. These fatty acids are converted in the body into oxylipins that influence pain. Oxylipins derived from EPA and DHA may reduce pain, while those derived from linoleic acid may increase it.

In this study, 182 people who had migraines on 5 to 20 days each month were randomly assigned to consume one of three diets for 16 weeks: a diet with increased EPA and DHA and a linoleic acid level the same as the average U.S. intake; a diet with increased EPA and DHA and reduced linoleic acid; or a control diet with levels of EPA, DHA, and linoleic acid the same as average U.S. intakes. The study used a modified double-blind design; the dietitian who counseled the participants knew which diet each individual was assigned to, but the other study staff and the participants did not.

Study participants completed the Headache Impact Test (HIT-6), a questionnaire that measures the impact of headaches on quality of life, at the beginning and end of the 16-week study. The researchers measured levels of 17-hydroxy docosahexaenoic acid (17-HDHA), a precursor of pain-reducing oxylipins, in samples of blood plasma from the participants. The participants also kept a daily headache diary.

Participants who received either of the modified diets had fewer total hours of headache, fewer hours of moderate-to-severe headache per day, and fewer days with headache per month, compared to participants on the control diet. Effects on HIT-6 scores were not statistically significant. Participants on the diet with increased EPA and DHA and decreased linoleic acid had fewer days with headache per month than those on the diet with increased EPA and DHA and average linoleic acid. Plasma 17-HDHA levels increased in participants on the modified diets, compared with the control diet.

The results of the study indicate that an increased intake of the omega-3 fatty acids EPA and DHA can reduce the frequency and severity of headaches and that reducing intake of the omega-6 fatty acid linoleic acid may lead to additional improvement. However, quality of life did not improve significantly with the diet modifications. The increase in 17-HDHA suggests that changes in oxylipins may have played a role in the reduction in headaches.

The researchers who conducted the study said that it provides a biologically plausible demonstration that pain can be treated through dietary alterations, thus opening the door to new approaches for managing chronic pain.