What is Inflammation? How to Recognize and Reduce it
Inflammation is a hot topic. But many people first just want to know, what is inflammation, really?
I am excited about this topic because the word inflammation is thrown around frequently, but most people cannot explain what it means. I recently had a patient ask me what inflammation is and I found I did not have a readily available answer due to the complexity involved with inflammation. Now, after gathering my thoughts and research, I have a better answer.
What is Inflammation?
Inflammation is, well, it’s inflammation in the body, right? We hear people talk about pro-inflammatory foods or that the cause of all disease is inflammation. Sugar and animal foods are pro-inflammatory, right? At least that is what we hear people say. Healthy diets are supposed to be anti-inflammatory. A long list of dietary supplements and health food products are also supposed to address inflammation but how do we know if they are working? Do antioxidants quench inflammation? These are all questions we should be asking when we are talking about this subject. I am going to dive a little deeper into the subject so that readers can have a more precise understanding.
Let’s clarify what inflammation is and discuss what is good and bad about it. Those who know me know that I am big on objective lab testing to measure things. It seems to me that most of the people who talk about inflammation or say they have chronic inflammation have never done any testing to measure it. I think most people barely understand what it is. The inflammatory response in the human body is quite complex and I think just attributing an issue to inflammation is a flippant response. I think the same thing happens with stress: a lot of doctors say an issue is caused by stress. The stress response is also somewhat complicated and there are different stress hormones released. It is not the same within everyone. Stress is acute and chronic too and may either suppress or activate the immune system.
What Causes Inflammation in the Body?
First, inflammation can be classified as either acute or chronic, and site-specific or systemic. There are five classic symptoms of local inflammation and they include swelling, heat, pain, redness, and the inability to use the body part involved. Inflammation comes from the Latin word inflammatio meaning to “set on fire”.
Inflammation is a response by the body against several different irritants. These irritants include pathogens of any type which include viruses, bacteria, and parasites. Irritants can be any harmful stimuli such as exposure to extreme cold, toxins, heat, or tissue damage of any kind such as that experienced by lifting weights or running downhill. Inflammation is also part of the healing process and part of how our immune system protects us from infections.
A robust immune response in the face of infections is one type of inflammation which we want—just not too much! Sometimes a high fever can be dangerous and even cause brain damage. The extreme immune response known as the “cytokine storm” experienced by patients with Covid-19 is another example. In this case the immune response is too strong, causing extreme inflammation in the lungs and making it hard for the patient to breathe which can lead to death.
In immune system terminology the inflammatory process is part of our innate immunity as compared to adaptive immunity which is a type of immunity that is specific for each pathogen. Think about it like a first line of defense ready to attack anything bad.
Types of Chronic Inflammation
Chronic inflammation is the main problem in human diseases. Hay fever and asthma are emblematic of a chronic overstimulated immune system. These affect the respiratory system causing airway restriction secondary to overexcited immune cells. Periodontal disease is a chronic inflammatory process that will eventually eat away at gums and even damage bone in the jaw. Atherosclerosis is a chronic inflammatory condition with many factors involved. Cholesterol builds up within the artery to the point where it becomes an irritant and inflammation will continue as long as that irritant is there. This process continues and builds on itself to the point where either the plaque ruptures or a complete obstruction occurs.
Osteoarthritis, the common type of arthritis, is also a situation in which immune cells are active within the joint. One of the problems with this condition is that enzymes are produced which eat away at the cartilage, destroying it and leading to bone-on-bone as time progresses.
Autoimmune diseases such as lupus and rheumatoid arthritis are conditions where the immune system is not only overly active, but it has been tricked into targeting the same body tissues it’s trying to protect. Autoimmune disease is an example of a major immune system dysfunction. Drugs used to treat autoimmune diseases essentially depress the immune system. Side effects of many of the drugs used to treat these conditions often include increased risk of cancer. The reason for this is that our immune system is constantly in surveillance mode and programed to kill cancer cells. We form them constantly and it’s our ability to recognize and take them out that prevents us from getting cancer.
Healing in the Body: When Inflammation is Helpful
Inflammation is important for healing. This is one reason why long-term use of NSAIDs (nonsteroidal anti-inflammatory medicine) can impair the healing of tendon, ligament, and joint injuries. NSAIDs inhibit prostaglandins which decreases pain in the short-term, but delays healing in the long-term.
Inflammatory conditions typically end with the word “itis” which is ancient Greek for “pertaining to.” In English medical terminology it almost always means a disease of which is inflammation mediated.
Acute inflammation is orchestrated by the immune cells already present in the damaged tissue. These include macrophages, mast cells, Kupffer cells, dendritic cells, and histiocytes. The cells have special receptors that bind to either pathogens or damaged tissue. The classic sign is vasodilation which increases blood flow and causes redness and heat. Blood vessels become leaky and proteins from the plasma leak out which causes swelling. If this was not bad enough there is a chemical called bradykinin which increases the sensitivity to pain. One reason the vessels become leaky is that the immune cells can easily travel within the tissue. Immune cells also release chemicals (cytokines, chemokines) that trigger more reactions. Acute inflammation is like the first line of defense. It should go away once the offending stimulus is gone.
There are also immunologically active proteins and enzymes in the blood, and these get triggered through chemical signaling. They have names like thrombin, plasmin, complement, and bradykinin.
The list of molecules secreted by our immune cells is very long. They are either proteins, enzymes, cytokines, chemokines, or prostaglandins. There is even a gas involved called nitric oxide which causes vasodilation. Interferons and interleukins cause fever and trigger increasing immune responses. All these factors work together to initiate and promote different healing processes.
I think a good way to define inflammation is: “a response by the body to an infection or damage that involves not only immune cells but also triggering chemicals in the blood that work together in a complicated process designed to heal. Inflammation can be acute or chronic. Chronic inflammation is the one associated with most diseases. Additionally, when inflammation is chronic, diseases progress and tissue gets damaged.” Examples are cartilage damage, arterial damage, and eczema. If you scratch eczema it just gets more inflamed and gets worse.
The Role of Inflammation in Disease
Is chronic inflammation the cause of most disease? I do not think it is always the cause, but I would say it’s certainly involved in the progression. More recent research has indicated that inflammation is more significantly involved in chronic disease than we thought it was. And yes, sometimes it is the cause. Inflammation works in a feed forward cycle. Once initiated it may continue causing more and more problems. In most chronic diseases there is a complex interplay between genetic and environmental factors that begins the process.
Research into atherosclerosis, which is the cause of most heart attacks, has revealed that therapies designed to target inflammation can work as well as treatments to lower cholesterol. [1] Cardiovascular disease including arterial disease is caused by oxidative stress that then causes inflammation within the artery and immune dysfunction leading to plaque growth. All these factors interplay with each other, so if there is oxidative stress but the patient undergoes treatments to reduce inflammation it thereby decreases the oxidative stress and immune dysfunction. It is a continuum of interacting factors that cause most cardiovascular diseases.
Cancer is also a chronic inflammatory condition once a person gets it. Long-term inflammation can damage DNA, increasing the risk of local cancers. Esophageal cancer is a good example where long-term acid reflux damages tissue enough that cancer cells are created. Other examples include liver cancer from chronic irritation to the liver due to alcoholism, and skin damage from the sun.
There is also some interesting data on the link between chronic inflammation and depression. [2] Maybe some of you have noticed that if you are fighting something your mood goes way down. Chemicals released by the immune system such as cytokines are the cause of this. There are receptors in the brain that trigger low mood.
Slightly newer research has shed a lot of light on the role of obesity and chronic inflammation. Obesity causes the type of chronic inflammation called systemic inflammation. [3] This is easy for doctors to know because blood markers of inflammation go up. These include interleukin’s, tumor necrosis factor, C-reactive protein, insulin, blood sugar, and the hormone leptin. When patients lose adipose tissue markers of inflammation decrease. I have seen this many times in my practice especially with the marker high-sensitivity C-reactive protein (hsCRP).
Testing for Inflammation and Finding Solutions
If you are reading this, you are probably interested in knowing if you have chronic inflammation. Is your diet really causing your inflammation or are you interested in making sure that your anti-inflammatory diet is really working? This is what most people want to know and is the most interesting part. Unfortunately, checking for inflammation is not part of the conventional medicine model. The only marker you can reasonably expect to get is high-sensitivity C-reactive protein. Also, measuring inflammation molecules is not helpful for most diagnosis and treatment. Diagnosing and monitoring chronic inflammation provides opportunities for a more targeted holistic approach. I run comprehensive inflammatory blood tests, especially for my heart disease patients, to get a better handle on the internal environment.
I highly recommend first starting with a whole food plant-based diet. This diet is strongly anti-inflammatory if done right. If blood tests reveal inflammatory markers that are elevated supplements can help. Typical ones include fish oil, Tumeric extract, vitamin C, vitamin D, Boswellia, green tea extract, and many more.
If you are interested in learning more and undergoing some testing, NatureMed has an inflammation panel for this that is quite extensive. It includes many of the inflammatory molecules I discussed above.
Contact NatureMed to schedule your appointment with Dr. Steve Parcell: 303-884-7557.
[1] Libby, P (19–26 December 2002). “Inflammation in atherosclerosis”. Nature. 420 (6917): 868–74. Bibcode:2002Natur.420..868L. doi:10.1038/nature01323. PMID 12490960. S2CID 407449.
[2] Canli, Turhan (2014). “Reconceptualizing major depressive disorder as an infectious disease”. Biology of Mood & Anxiety Disorders. 4: 10. doi:10.1186/2045-5380-4-10. PMC 4215336. PMID 25364500.
[3] Parimisetty A, Dorsemans AC, Awada R, Ravanan P, Diotel N, Lefebvre d’Hellencourt C (24 March 2016). “Secret talk between adipose tissue and central nervous system via secreted factors-an emerging frontier in the neurodegenerative research”. J Neuroinflammation (Review). 13 (1): 67. doi:10.1186/s12974-016-0530-x. PMC 4806498. PMID 27012931.