A COVID-19 prophylactic?/Craig Medred photo

The Omega-3 benefits of eating salmon have long been known, but a new study out of the Cedars-Sinai Medical Center in California suggests a special protective value for these pandemic times.

Researchers there say they have found indications that Omega-3 fatty acids are protective against death from COVID-19, the disease caused by the SARS-CoV-2 virus.

After tracking the Omega-3 Index (03I) in 100 COVID patients, they reported discovering “that those patients with an O3I at 5.7 percent or greater were at about 75 percent lower risk for death compared with those below that value.”

Blood levels of O3I, the study noted, are “easily modified by increasing the intake of oily fish (for example, salmon, herring, mackerel, albacore tuna, etc.).”

The sample size for the pilot study, which was posted online at MedRxiv today and which has not been peer-reviewed, is small,  and the researchers pointedly warned that “these findings suggest that a relationship may indeed exist, but larger studies are clearly needed.

“Multiple randomized clinical trials (RCTs) are currently, as of January 2021, underway testing the hypothesis that treatment with omega-3 fatty acids (EPA and DHA) will have beneficial effects on a variety of aspects of COVID-19 infection,” the researchers wrote.

RCTs are considered the gold standard of medical research. But whatever those trials find, there is no documented downside to increasing consumption of oily fish now except in those cases where the fish have bioaccumulated persistent organic pollutants (POPs) or mercury.

The Alaska Department of Environmental Conservation monitors Alaska fish for those contaminants, and the Alaska Department of Health and Social Services provides fish consumption advice. 

All five species of Alaska salmon have been found clean of these pollutants and cleared for “unrestricted consumption.”

Past research supportive

The Cedars-Sinai researchers pointed out there are plenty of good reasons to encourage increased cosumption of such seafood.

“Although (RCT) outcomes are not yet known (in the case of COVID-19),” they wrote, “there are compelling scientific reasons to expect that these studies will be positive, and these same reasons formed the foundation for the present study. The data supporting a possible beneficial role for omega-3 fatty acids in COVID-19 infection come from past epidemiological, interventional, therapeutic, and basic science studies.

“For example, in the Framingham Offspring study, the O3I was inversely associated with 10 separate inflammatory biomarkers….Meta-analyses of multiple RCTs confirmed that treatment with omega-3 fatty acids routinely lowers cytokine levels.”

Cytokines are biochemicals that allow cells to communicate with each other. They are vital to the operation of the body’s natural immune system. But in people with COVID-19, an over-abundance can cause what have been labeled “cytokine storms.”

Cytokine storms are what often lead to the death of people infected with SARS-CoV-2.

The Cedars-Sinai study specifically noted this danger and observed that “an attractive preventative approach to COVID-19 infection is to
minimize cytokine release. Very long-chain omega-3s found in fish oils have a plethora of biological activities including directly and indirectly modulating inflammatory responses and cytokine release.

“Given the profound public health concerns related to the current COVID-19 pandemic, modifiable risk factors for developing severe and critical complications are urgently needed, especially ones that may be nutritionally-based.”

The Cedars-Sinai research is probing new ground. The researchers said they could find no indication that anyone had previously “explored the relationship between omega-3 tissue levels and COVID-19 outcomes.”