Should You Switch to Fish Oil With PRMs?

Pro-resolving mediators (or PRMs) have been touted as essential to quality fish oil supplements. But what does the research (or lack thereof) really tell us?

Monica Reinagel, MS, LD/N, CNS
5-minute read
Episode #584
The Quick And Dirty
  • Pro-resolving mediators are produced in the body to fight inflammation.
  • Consuming fish or fish oil can increase PRMs in the body.
  • There is no research to show that a fish oil supplement with PRMs is more effective than fish oil alone. 

Kelly writes:

My chiropractor is recommending that I switch to fish oil with 'pro-resolving mediators' or PRMs. What are PRMs? Could I buy them separately and take them with the fish oil I’m already taking rather than switching to her more expensive fish oil product, which (unlike the one I’m taking) is not third party tested for purity?

What are PRMs?

One of the things I love about this job is that I’m never done learning. And I have to confess that Kelly’s email was the first I’d ever heard of pro-resolving mediators! Let me fill you in on what I’ve learned.

Fish oil is rich in the omega-3 fatty acids EPA and DHA. Most American adults don’t get the recommended amount of these nutrients from their diet and a fish oil supplement can help to fill that gap. Fish oil is also used in higher, therapeutic doses to treat and prevent a wide variety of health conditions, including heart disease, auto-immune disorders, arthritis, and even depression.

There are a few different mechanisms of action. Omega-3s are anti-thrombolytic, meaning that they reduce the tendency of blood to form clots. They are also potent anti-inflammatories.

How omega-3s work in the body

Omega-3s are enzymatically converted in the body into various biologically active molecules, which orchestrate the body’s inflammatory and immune responses at the cellular level. There are a lot of different types of these active compounds, including prostaglandins, eicosanoids, and leukotrienes.

The three main types are protectins, resolvins, and maresins. (The fact that the three PRMs start with P, R, and M, is quite handy.)

Pro-resolving mediators (or PRMs) are a newly recognized category of these active compounds. The three main types are protectins, resolvins, and maresins. (The fact that the three PRMs start with P, R, and M, is quite handy.) In some papers, they are referred to as SPMs, which or Specialized Proresovlng Mediators, which isn’t nearly as handy as a mnemonic device, so I’ll stick with PRMs.

How do PRMs promote health and healing?

As the name implies, pro-resolving mediators act to actively resolve or turn off the body’s inflammatory responses.

Inflammation is not necessarily a bad thing. It’s part of the body’s immune response and, in the right place and the right time, it serves a very important function.

Chronic or excessive inflammation, on the other hand, can start to create problems. And that’s where the PRMs come in: their job is to switch off inflammatory activity once the immediate threat has been dealt with, which allows the inflammation to resolve and healing to begin.

Some research suggests that in diseases characterized by chronic or inappropriate inflammation, there may be some sort of disruption in the body’s production of these PRMs.  Other research shows that supplementation with omega-3 fatty acids, like those in fish oil, can increase the amount and activity of PRMs in the body. But if your body makes PRMs when you take omega-3, why would you need to take them as a supplement?

Why, indeed?

Is fish oil with PRMs more effective?

Including PRMs in a fish oil supplement may be a way to distinguish your product in a crowded marketplace, and to sell it at a premium price. But there doesn’t appear to be any published research in humans showing that taking a supplement containing PRMs would accomplish anything more than supplementing with fish oil.

I even stumbled across a couple of supplements where PRM stood for Pre-Resolving Mediators instead of pro-resolving mediators. The marketing material explains that pre-resolving mediators are the precursors the body needs to make pro-resolving mediators. In other words, plain old fish oil!

What's the research on PRMs?

As for actual pro-resolving mediators, there’s very little research to speak of. (Remember, it’s only been a few years since we discovered them.) Since then, a few studies have looked at the effects of individual cell types in Petri dishes. But what happens to a cell in a petri dish and what happens to cells, tissues, and organs in a living organism is a very different thing.

What happens to a cell in a petri dish and what happens to cells, tissues, and organs in a living organism is a very different thing.

There are also some rodent studies that at least look at the effects of PRMs in vivo, but these are simply looking for mechanisms of action. They don’t compare the relative effectiveness of PRMs to other anti-inflammatory agents, such as fish oil. I expect that more research will follow, but it will be a while before we get to the level of research that would test the safety and effectiveness of PRM supplements on symptoms or risk factors in human beings. In the meantime, I don’t think there’s any reason to shell out for fish oil with PRMs.

Should healthcare providers sell supplements?

Many health care practitioners recommend nutritional supplements to their patients and clients. Some of them also sell these products. Often, this is seen as a convenience to the patient. Instead of having to hunt for a specific product or research the differences between various brands, you can walk out the door with your practitioner’s preferred brand in your hand. Sometimes, healthcare practitioners even have access to brands and products that are not readily available through direct-to-consumer channels.

We want to trust that our practitioners’ advice and recommendations are based solely on our needs. But when part of their income stream comes from supplements ... it presents a conflict of interest.

However, it does introduce a thorny issue: We want to trust that our practitioners’ advice and recommendations are based solely on our needs. But when part of their income stream comes from supplements or other products that they sell, it presents a conflict of interest. A more expensive product usually brings in more revenue. So does a more aggressive supplementation regime.

I think it’s hard for even the most ethical and well-intentioned practitioner to be 100 percent objective in this situation. A busy practitioner may not have time to thoroughly research and follow the science behind various supplements. They rely pretty heavily on the information provided by the sales representative, who is going to present their products in the best possible light, exaggerating the positive effects (and the positive cash flow) and minimizing any gaps in the research or information about alternatives. 

Sometimes, it’s not even the practitioner who is choosing these products but an office manager, who may not have any training in nutrition but whose job it is to run a profitable (or at least solvent) practice. 

If all of this sounds familiar, it’s because it’s similar to the model by which pharmaceuticals are sold to healthcare professionals. Most physician education on the effectiveness of drugs and medical devices is provided by the companies that sell them. As a result, the drugs most frequently prescribed are not necessarily the most effective or cost-effective choices. And the same is true for nutritional supplements sold by healthcare practitioners—even the really well-meaning ones.

If you have a question about whether a high-priced supplement is worth the money, feel free to send it my way. I may include your question in an upcoming episode.

About the Author

Monica Reinagel, MS, LD/N, CNS

Monica Reinagel is a board-certified licensed nutritionist, author, and the creator of one of iTunes' most highly ranked health and fitness podcasts. Her advice is regularly featured on the TODAY show, Dr. Oz, NPR, and in the nation's leading newspapers, magazines, and websites. Do you have a nutrition question? Call the Nutrition Diva listener line at 443-961-6206. Your question could be featured on the show.