“No inflammation/ no repair is a valid dictum.”
~ Carrico et al 1984
Inflammation has become a dirty word these days. Anyone who braves the internet will see much to do about “fighting inflammation” and “anti-inflammatory” products. A quick tippity-tap or two into the old search bar will lend you list upon list of action steps and products (that you can buy!) to help you get inflammation out of your life.
This might surprise you but I am not in the fight against inflammation. I consider inflammation a friend not foe because I know that without it, we would all be dead later today and, if not, then very soon after. Turns out, inflammation is absolutely necessary for healing*. So, if a cut, scrape or break doesn’t get you then you woud certainly bleed out internally in the absence of inflammation as your guts are in a constant dance of inflammation and healing (this is why ulcers and gut bleeds are a side effect of NSAID’s but more on this later).
To understand inflammation better let’s start with an easy example. Imagine that you are quite hungry and it is still morning time so you settle on a bagel to curb this crisis. It’s an everything bagel because that just sounded more satiating. At this point there is a large bread knife in one hand and a bagel perpendicular to the counter in the other. At first you have to press pretty hard with the knife because the bagel is so thick but then, suddenly, you hit that hole in the middle and your cutting hand is still applying the same amount of pressure needed to plow through the bagel’s thickest section. The knife hand moves at alarming speed while the other hand tragically slips on a poppy seed. Knife serrations meet your index finger and the deep parts of your skin feel the air before blood bubbles to the surface of a freshly minted flesh wound. Then a wave of shame passes over you because the first thought that comes to mind is if cream cheese can cover up the rich metallic taste of blood. This being your first thought as opposed to something less barbaric like “where are the band-aides?”. This saga did begin with hunger after all. Sound familiar?
In response to the damage, the body mounts an immediate response. Initially blood vessels constrict and clotting factors work to make a seal to stop further loss of blood. However, blood supply to the area will actually increase shortly after as a whole host of special cells and proteins are delivered to the injured area. White blood cells enter the scene to clean up dead and dying cells as well as any foreign matter that may have entered through the cut. Chemicals that are released from the site of the damage create a chemical gradient to move the white blood cells right to the heart of the action. Plasma proteins will enter into the milieu some as antibodies and clotting factors and others as the building blocks for the repair that needs to be made. The increased activity and fluid to the area results in heat, redness, and swelling. The pain comes from increased sensitivity as the area is flooded with various chemicals. In short, it is exquisitely orchestrated, purposeful, and effective as well as uncomfortable as hell.
Acute inflammation is completely necessary for healing. Depending on the tissue that is damaged, the repair process will have varying amounts of success. In the case of many tissues, the repair is regenerating the damaged tissue in likeness to the original tissue while other tissues are only capable of being repaired with scar tissue. Tissues that are susceptible to frequent damage and thus are well suited for repair and regeneration such as the skin, the tissues lining the gut and vagina, and other epithelial tissues repair quickly and regenerate in likeness to the original. Tendons, ligaments, fascia and bone also repair in likeness but are slower to heal. Damage that occurs to cartilage, cardiac or smooth muscle, certain organs, glands and large wounds involving multiple tissues will repair as scar tissue or at least some amount as scar tissue.
Another point I want to make about inflammation is that it does not just occur in the case of overt trauma such as a laceration, fracture, strain or burn. Inflammation can also result from repetitive or chronic overuse of a tissue in the absence of a discrete injury. Actually, inflammation can show up just from an increase in activity or when starting a new activity. That’s right kids delayed onset muscle soreness is really just inflammation trying to make repairs to those muscles and other tissues that you beat up on your first run back in a while.
Ok so the signs of inflammation have dissipated and you were able to consume that bagel albeit gingerly with the use of one hand. Are you all healed up now? No! Of course not. Inflammation was just the beginning. What comes next in the healing process will be covered in the subsequent parts of this series. Next, however, we will take a pit stop to explore what happens with inflammation in a few specific scenarios. Inflammation is a big topic after all and we will linger here to discuss more about the nature of inflammation and to reflect on how to live with it gracefully.