In a recent study published in the Journal of the International Society of Sports Nutrition, researchers found that cod liver oil as a source of omega-3s had a greater impact on resting and exercise-induced inflammation compared to any and all other sources across a population of cyclists.
 
“Some studies have reported no effect of omega-3 fatty acid supplements on inflammatory markers following exercise,” the authors of the study wrote. “These diverging findings may relate to type, intensity, and duration of exercise, the population studied, timing of sampling, and the type of inflammatory markers used to assess the response.” However, there may also be important differences when it comes to the ingredients sourced to formulate omega-3 supplements.
 
In a prospective, observational trial, the authors of the present study documented the fish oil consumption habits of 1,002 healthy, recreational athletes, and took measurements of their C-reactive protein (CRP – a marker of inflammation) levels both before and immediately after a 91-km bicycle race.
 
856 of the participants in the study said that they used omega-3 fatty acid supplements prior to the race, however, only 274 of the subjects said that they did so regularly. Among these, 173 omega-3 supplement users used cod liver oil specifically. The regular users of omega-3 fatty acid supplements had a 27% lower CRP response than non-users, which was adjusted to 16% after adjusting for age, sex, race duration, BMI, and other exercise and metabolic factors.
 
However, when broken down in terms of the source of omega-3 fatty acids, the researchers said that cod liver oil was the primary driver of the overall responses that people had to omega-3 supplementation – people who took their omega-3s from this source had a 34% reduction in CRP response compared to non-users.
 
In the broad scheme of research on the influence of omega-3s and inflammation, the authors of the present study suggest that cod liver oil as a source is relatively under-investigated, and omega-3 supplement studies don’t tend to take into account the possible role that the presence of vitamins A, E, and D in cod liver oil has on inflammatory response.
 
Moreover, potential advantages of delivery formats and quantities typically taken should be accounted for – generally speaking, cod liver oil, which is taken by teaspoon, has been shown in product studies to typically be less oxidized on the market compared to other omega-3 supplements, and because it is taken by a spoon, people may generally take higher doses with greater ease, the authors said.