Inflammatory response is essential for health. So is toning it down once the healing is done. Here’s how omega-3s help. 09/17/2020
Inflammation is a normal part of the human body’s healing process. When we’re hurt, inflammation helps heal injuries and fight off infection. Immune cells rush to the injured area to thwart microbial invaders and repair damage. In the process of fixing the problem, they also cause swelling and pain.
But sometimes inflammation happens even when there’s no obvious ailment to heal. If we’re regularly stressed out, not eating properly, lack sleep, or don’t exercise, these can cause inflammation that wreaks havoc throughout the body (NIEHS).
You might not feel this chronic inflammation the way you feel a cut or head cold, but it can be even more serious. Chronic, whole-body inflammation can lead to arthritis, Alzheimer’s, heart disease, diabetes, obesity, cancer, and more (Lumeng and Saltiel, 2011) (Coussens and Werb, 2002).
In fact, it seems to play a role in most of the chronic conditions informally known as the “diseases of civilization.”
However, for years now, studies have shown that consuming omega-3 fatty acids from seafood helps fight chronic inflammation (Kiecolt-Glaser et al., 2011).
Research suggests eating just a few servings of seafood a week, especially wild-caught salmon, sardines, and mackerel, provides the body with two important omega-3 fats called EPA and DHA that are not easily found elsewhere in nature.
Omega-3s and Inflammation
EPA and DHA are vital to the body for many reasons, and they form the building blocks for cells throughout our body. You’ll find them in especially high amounts in our brains and eyes. They help provide energy for the heart, blood, and lungs (NIH ODS). They’re essential from the womb through old age, helping fetuses develop and seniors remain healthy (Swanson et al., 2012).
The secret to some of their broad health benefits could lie in how they help control inflammation. For example, some studies show DHA’s anti-inflammatory abilities can reduce the risk of heart disease and symptoms of arthritis.
But why do these omega-3s help fight inappropriate inflammation in the first place? And what happens to the fatty acids after we eat them? Scientists are still piecing together the specifics. The emerging picture is that inside our bodies, omega-3s are used as the raw materials for compounds that are powerful inflammation controllers (Serhan 2014).
Scientists now know that our cells turn DHA and EPA into compounds called maresins, resolvins, and protectins. They’re what scientists call “specialized pro-resolving mediators,” or SPMs.
Don’t let the jargon throw you – it simply means these compounds work to dial back inflammation after the body is recovered from an injury or infection (Tang et al., 2018).
At the most basic level, you can think of our immune system as an arsenal of weapons that gets unleashed in response to new threats.
And SPMs are the body’s peacekeepers, calming down defensive forces after a threat has been handled.
Increasingly, research is showing just how powerful SPMs can be. They seem to play a helpful role in a variety of disorders and conditions connected with inflammation, from inflammatory bowel disease to arthritis, Alzheimer’s disease, and more.
SPMs can even help control allergic reactions. Several studies have also shown that certain health problems, like severe asthma, seem to be caused by the body failing to make enough SPMs (Miyata et al., 2015).
Though maresins, resolvins, and protectins all help fight inflammation, each appears to play a slightly different role.
Maresins are made from macrophages, the white blood cells from the immune system that gobble up everything from cancer cells to foreign debris (Tang et al., 2018).
After we eat seafood, macrophages also consume DHA and transform it into maresins. It appears that maresins are important for a staggering variety of functions. They help heal wounds and reduce pain, as well as resolve inflammation and aid in the control of allergic reactions (Levy and Serhan, 2014).
In a study done on mice with spinal cord injuries, scientists found that maresins played a major role in controlling how the body healed (Francos-Quijorna et al., 2017).
They worked like a traffic cop to stop some healing processes at the right time, reducing inflammation, while simultaneously redirecting other immune responses. The team also successfully implanted the compound at the injury site and sped up the healing process.
The researchers say their findings hint that scientists could treat spinal cord injuries by better using the natural healing powers of maresins.
Another class of SPMs is resolvins. These are the compounds that give aspirin its potent inflammation-stopping abilities — the drug kickstarts production of resolvins in the body.
But our bodies can also make resolvins from DHA and EPA. In fact, both aspirin and omega-3s lead to the production of the same resolvin, D3 (Dalli J et al., 2013). That discovery has sparked new interest in using omega-3s as a safer anti-inflammatory agent.
And in early studies giving omega-3 fatty acids to people with cancer and kidney disease, researchers saw signs it helped improve inflammation. The scientists think resolvins could have been involved (Moro et al., 2016).
Like the other SPMs, protectins also have an important role in controlling inflammation and protecting our brains. Alzheimer’s disease studies done on animals, as well as research on stroke patients, suggests protectins may reduce some of the inflammation associated with those diseases. They may even forestall some cell damage (Hansen et al., 2019).
SPMs could even help stop the flu in its tracks. In a study of flu patients, researchers found omega-3-derived SPMs prevented the influenza virus from replicating, ending the deadly illness’ spread (Morita et al., 2013).
With only a decade or so of research into SPMs so far, scientists still have much to learn about how our bodies fight inflammation with omega-3s. But the early results have shown enough promise to spark an explosion of research.
And in the meantime, it’s providing evidence for something many consumers have long known: Food is often the best medicine, and seafood is among the best foods.
National Institute of Environmental Health Sciences. Introduction to Inflammation. https://www.niehs.nih.gov/health/topics/conditions/inflammation/index.cfm
Lumeng CN, Saltiel AR. Inflammatory links between obesity and metabolic disease. J Clin Invest. 2011;121(6):2111-2117. doi:10.1172/JCI57132
Coussens LM, Werb Z. Inflammation and cancer. Nature. 2002;420(6917):860-867. doi:10.1038/nature01322
Kiecolt-Glaser JK, Belury MA, Andridge R, Malarkey WB, Glaser R. Omega-3 supplementation lowers inflammation and anxiety in medical students: a randomized controlled trial. Brain Behav Immun. 2011;25(8):1725-1734. doi:10.1016/j.bbi.2011.07.229
National Institutes of Health Office of Dietary Supplements: Omega-3 Factsheet. https://ods.od.nih.gov/factsheets/Omega3FattyAcids-Consumer/#h1
Swanson D, Block R, Mousa SA. Omega-3 fatty acids EPA and DHA: health benefits throughout life. Adv Nutr. 2012;3(1):1-7. doi:10.3945/an.111.000893
Serhan, C. Pro-resolving lipid mediators are leads for resolution physiology. Nature 510, 92–101 (2014). https://doi.org/10.1038/nature13479
Jun Miyata, Makoto Arita, Role of omega-3 fatty acids and their metabolites in asthma and allergic diseases, Allergology International, Volume 64, Issue 1, 2015, Pages 27-34, ISSN 1323-8930, https://doi.org/10.1016/j.alit.2014.08.003
Tang S, Wan M, Huang W, Stanton RC, Xu Y. Maresins: Specialized Proresolving Lipid Mediators and Their Potential Role in Inflammatory-Related Diseases. Mediators Inflamm. 2018;2018:2380319. Published 2018 Feb 20. doi:10.1155/2018/2380319
B.D. Levy, C.N. Serhan, Resolution and Regulation of Inflammation, Editor(s): Linda M. McManus, Richard N. Mitchell, Pathobiology of Human Disease, Academic Press, 2014, Pages 332-348, ISBN 9780123864574, https://doi.org/10.1016/B978-0-12-386456-7.01811-6
Francos-quijorna I, Santos-nogueira E, Gronert K, et al. Maresin 1 Promotes Inflammatory Resolution, Neuroprotection, and Functional Neurological Recovery After Spinal Cord Injury. J Neurosci. 2017;37(48):11731-11743.
Dalli J, Winkler JW, Colas RA, Arnardottir H, Cheng CY, Chiang N, Petasis NA, Serhan CN. Resolvin d3 and aspirin-triggered resolvin d3 are potent immunoresolvents. Chem Biol. 2013 Feb 21;20(2):188-201. doi: 10.1016/j.chembiol.2012.11.010.
Moro K, Nagahashi M, Ramanathan R, Takabe K, Wakai T. Resolvins and omega three polyunsaturated fatty acids: Clinical implications in inflammatory diseases and cancer. World J Clin Cases. 2016;4(7):155-64.
Hansen Trond Vidar, Vik Anders, Serhan Charles N. The Protectin Family of Specialized Pro-resolving Mediators: Potent Immunoresolvents Enabling Innovative Approaches to Target Obesity and Diabetes. Frontiers in Pharmacology. Volume 9. 2019. Pages 1582. DOI=10.3389/fphar.2018.01582
Masayuki Morita, Keiji Kuba, Akihiko Ichikawa, Josef M. Penninger, Makoto Arita, Yumiko Imai The Lipid Mediator Protectin D1 Inhibits Influenza Virus Replication and Improves Severe Influenza. Cell. March 07, 2013 doi:https://doi.org/10.1016/j.cell.2013.02.027