Understanding Inflammation

May 5, 2022 by spencerjean_do

Unless you’ve really been out of the loop, you’ve surely heard inflammation is to blame for almost every known malady. Or at least, that’s what the diet, supplement, and self-help ads claim. But, even if the health-care marketplace has overhyped and oversold inflammation in its relentless search for the next big thing, it’s no exaggeration to say inflammation plays a key role in a wide range of conditions—from depression to tendon pain, fibromyalgia to cancer, and joint problems to aging itself.

There are also bigger questions about the nature and function of inflammation that might influence the way we think and work. What roles do the brain and nervous system play? How do psychosocial factors (such as stress or depression) play into inflammation? Could pain itself be a type of inflammatory response?

Let’s start by reviewing some inflammation basics.


Inflammation is simply the immune system’s tissue protection and repair response. It can be triggered by injury, infection, or irritation. Inflammation is necessary and good: though it can be uncomfortable, without inflammation, the body can’t protect or heal itself. Normally, inflammatory responses are self-limiting, and wind down when their protection and repair tasks are complete.


Problems happen when there is either:

    • Hypoinflammation, such as when a compromised immune system can’t fight an infection or heal an injury; or
    • Hyperinflammation, which can happen when either immune reactions are out of proportion to the threat (as in allergic reactions or autoimmune disorders) or when normal inflammatory reactions don’t resolve and become chronic.

Chronic or unresolved inflammation is implicated in an ever-lengthening list of conditions, including asthma, Alzheimer’s, depression and mental illness, hypersensitivities, rheumatoid arthritis, metabolic syndrome, and certain cancers. Inflammation is not only a factor in nearly all chronic diseases, but also in nearly all musculoskeletal complaints, including chronic pain.


Healthy inflammatory responses progress over time, moving through acute, repair, and adaptation phases (Image 2). Though many of these functions happen simultaneously (for example, resolution processes begin even while inflammatory processes are in their early development), each step sets the stage for the next.


Within seconds or minutes after damage, danger, or pathogen detectors trigger an acute inflammatory response, proinflammatory histamine and kinins increase vascular and cell permeability, and the affected tissues swell with plasma and immune cells (such as leukocytes). Cytokines (signaling proteins) recruit roaming immune cells; local warmth and redness (Image 3) indicate that the active inflammatory responses are at work; and pain and tenderness (from nociceptor irritation by proinflammatories, pressure from swelling, and protective reactions) help guard against further strain or mechanical distress during this initial phase.


Within hours or days, specialized cells (such as mononuclear cells and macrophages) begin the process of degrading and removing damaged or diseased cells. Once unleashed, these destructive processes are kept in check by innate anti-inflammatory and pro-resolution mechanisms to minimize “bystander” damage to other tissues.  Simultaneously, fibroblasts (which themselves have strong anti-inflammatory capacities) and other cells begin new tissue formation. Local warmth and redness diminish, as does pain—though pressure or stretch can still provoke protective tenderness as the new tissues form.


In the days, weeks, or months that follow, the proinflammatory process gradually matures and diminishes as the first-responder cells themselves become the target of degradation and cleanup via phagocytic, lymphatic, and other resolution mechanisms. Tissue strengthening continues, as fibroblasts cross-link collagen structures. Sensation normalizes and tenderness diminishes as the adapting brain gradually reevaluates and relinquishes the need for protective guarding.

  • IMAGE 1.
  • IMAGE 2.
  • IMAGE 3.

There’s a lot to know about inflammation, and this intimidating graphic will keep even hard-core geeks busy for a while. For the rest of us, the simplified version is that a pathogen or injury (upper left) initiates a sequence of inflammatory processes (upper half, in red) that release proinflammatory substances and move plasma and specialized cells from blood vessels into the tissues, where they are monitored and regulated by the peripheral nervous system (the vagus nerve in this instance, top). Meanwhile, anti-inflammatory and pro-resolution processes (lower half, in green) temper and balance the inflammatory progression. The vagus nerve (bottom) plays a direct role in controlling systemic inflammation via its release of anti-inflammatory compounds. As the inflammatory progression matures (from the left to right of the graphic), the resulting large proteins are processed by the lymphatic system and other mechanisms (Re, lower left). If you want even more detail about this illustration, go to http://bit.ly/luchau-gallo2017. Image: Gallo et al., 2017, used under CC BY-NC-ND 4.0.

Normally, inflammation progresses through acute, intermediate (repair), and later (adaptation) stages, each with its own mechanisms and processes (see text). When any stage’s progression is inhibited or prolonged, inflammation can become chronic. Resolution timelines vary tremendously, depending on the individual, the tissue, or the organ involved, etc., with full recovery in some cases taking months or years. After Steinacker et al., 1999, courtesy Advanced-Trainings.com.


Swelling, warmth, redness, and pain of acute inflammation. Though uncomfortable, these are signs of the healing processes at work.


Problems arise when any of these stages fails to resolve, and the inflammation becomes ongoing or chronic. This can happen when the immune system is overwhelmed by pathogens or damage, or when its resilience is taxed by stress, inactivity, diet, lack of sleep, etc. Factors such as adverse childhood experiences4 or genetics can also predispose us to chronic inflammation. But the causes of many chronic inflammatory conditions are not fully understood. These include autoimmune disorders, such as rheumatoid arthritis; fibromyalgia; and “inflamm-aging,” the low-grade inflammation-like changes that accompany aging.

In prolonged inflammation:

    • Fibroblasts, which usually have strong anti-inflammatory effects, can instead play an inflammatory role. Together with myofibroblasts, their unregulated activity over time can cause tissue fibrosis, stiffening, and pathologic scarring.
    • Treatment-resistant depression is more common, supporting the idea that some depression has inflammatory causes.
    • Pain can be persistent and difficult to treat. A recent study found that pain sufferers who didn’t respond to other forms of therapy had higher levels of chronic inflammation, suggesting (though not confirming) that inflammation can directly trigger persistent pain responses

Now that you have a better understanding of inflammation; keep an eye out NEXT WEEK for the next article “UNDERSTANDING INFLAMMATION AND PAIN” where I talk about how inflammation causes pain in both chronic and acute conditions.

If you have any questions or concerns about your inflammation or condition, please reach out to us at 519-735-7555.

13:48 28 Feb 22
The guy is a wizard. I’ve been looking for a long time for someone that knows what they’re doing when it comes to backs. I will only see Spencer now going forward. If you decide to see someone else for back pain I’m not sure if you really want to get better. Whole clinic is great.
Mallika SomayajuluMallika Somayajulu
16:26 22 Feb 22
Dr. Spencer is awesome. Because of him, My back pain is gone and I can do the things I like again. His staff are very professional and polite.
mariette renaudmariette renaud
19:56 11 Feb 22
After many years of cervical spine discomfort and osteoarthritis most likely as a result of sitting at a desk for a good number of years, I found myself wanting to find an alternative means towards improving my spine health!My Naturopath Doctor recommended I see an Oesteopath namely Spencer Jean who came highly recommended.Spencer welcomed me into his office and the conversation began as to how to go about the process of correcting my posture! A plan of attack was formulated as to how to begin the process which was amazingly positive based on his confidence in doing so along with my part in wanting to do so!Today my posture has improved tremendously and I cannot thank Spencer enough for getting me to this point! The exercises are not difficult and As I see the progress, I am so much more encouraged in doing so! Thank you so much Spencer and the wonderful welcoming staff at Community Chiropractic Centre! I am truly blessed!
Spencer has been a great benefit to me, as he listens to what is wrong and works to help with that problem; so that I get some relief & can do more of my ADL. Before meeting Spencer & being under his care; I had very limited relief of discomfort. I would recommend anyone with chronic pain & skeletal ailments to give Spencer a try. He maybe just what you need in your life.
Tea MalbasicTea Malbasic
13:23 13 Jul 21
Spencer is great! Very professional and caring. After years of chronic back pain, I can honestly say I feel better after every visit. The office staff is friendly and very easy to deal with!
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03:18 17 Jul 20
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Olivia RivardOlivia Rivard
16:43 21 Oct 19
Spencer is an amazing osteopath. I brought my 3 week old to see him for colic and he has helped her immensely! She is now 3 months and doing so well. Spencer is fantastic with babies. He is so caring and my little just adores him! Highly recommend his service.
Steven GombaiSteven Gombai
18:10 06 Aug 19
I actually love going to see Spencer. He addresses my problems and I'm not sitting around for hours past my appointment time waiting to see him. In and out within 30 minutes. He takes care of my kids as well. I would recommend him to anyone without hesitation.Thanks for keeping us all in one piece and keeping us at our 100% for our tournaments.

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