In the comments section of last week’s post on inflammation , many of you expressed a desire for a post explaining how to know if one is actually suffering from systemic, chronic inflammation. I thought that was a great idea and decided to put the other followups on hold so I could tackle this one. Obviously, it’s easy to tell if you’ve got some acute inflammation going on – swelling, pain, heat radiating from a part of your body that’s suddenly assumed a rosy hue, and throbbing open wounds are all blatant indicators of the inflammatory process at work – but tests for markers of inflammation are not yet standard across most medical practices. With that in mind, I’ll be giving info on both objective markers for which you can test, as well as on the subjective markers I use on myself that you can “test” and use to evaluate your own level of inflammation.
Let’s get to it.
CRP, or C-Reactive Protein
CRP  is a protein that binds with phosphocholine on dead and dying cells and bacteria in order to clear them from the body. It can always be found (and measured) in the bloodstream, but levels spike when inflammation is at hand. During acute inflammation caused by infection, for example, CRP can spike by up to 50,000-fold. CRP spikes due to acute inflammation peak at around 48 hours and decline pretty quickly thereafter (post acute-phase inflammation CRP has a half life of 18 hours). Thus, if the incident causing the inflammation is resolved, CRP goes back to normal within a few days. If it persists, the infection/trauma/etc. probably persists as well.
CRP elevates in response to essentially anything that causes inflammation. It’s highly sensitive to many different kinds of stressors. This makes it valuable for determining that inflammation is occurring, but it makes it difficult to determine why that inflammation is occurring – because it could be almost anything. But if you’re looking for confirmation that you are chronically, systemically inflamed, an elevated CRP in absence of any acute infections, injuries, burns, or stressors is a useful barometer.
“Normal” CRP levels are supposedly 10 mg/L. Absent infection or acute stressors, however, ideal CRP levels are well under 1 mg/L. You want to stay well below 1; you don’t want “normal.” Between 10-40 mg/L (and perhaps even 1-9 mg/L, too) indicates systemic inflammation (or pregnancy), while anything above that is associated with real acute stuff. Note that exercise can elevate CRP.
IL-6, or Interleukin-6
T cells (type of white blood cell that plays a huge role in the immune response) and macrophages (cells that engulf and digest – also known as phagocytosing – stray tissue and pathogens) both secrete IL-6 as part of the inflammatory response, so elevated IL-6 can indicate systemic inflammation.
Tissue Omega-3 Content
This is a direct measurement of the omega-3 content of your bodily tissue. It’s not widely available, but it is very useful. Remember that anti-inflammatory eicosanoids draw upon the omega-3 fats  in your tissues and that inflammatory eicosanoids draw upon the omega-6 fats . People having a higher proportion of omega-6 fats will thus produce more inflammatory eicosanoids. Now, we absolutely need both inflammatory and anti-inflammatory eicosanoids for proper inflammatory responses, but people with high omega-6 tissue levels make way too many inflammatory eicosanoids. Studies indicate  that people with the highest omega-3 tissue levels suffer fewer inflammatory diseases (like coronary heart disease).
Research (highlighted and explicated here by Chris Kresser ) suggests that omega-3 tissue concentrations of around 60% are ideal , which is a level commonly seen in Japan – seemingly paradoxical land of high blood pressure, heavy smoking, and low coronary heart disease rates.
This measures the EPA and DHA, the two important omega-3 fatty acids , as a percentage of total fatty acids present in your red blood cells. It doesn’t correlate exactly to tissue amounts, but it’s pretty good and a powerful predictor of cardiovascular disease risk. The omega-3 index doesn’t measure omega-6 content, but those with a low omega-3 index are probably sporting excessive omega-6 in their red blood cells.
Anything above 8% corresponds to a “low risk,” but levels of 12-15% are ideal and roughly correspond to the 60% tissue content mentioned by Chris’ article. 4% and below is higher risk and can be viewed as a proxy for increased inflammation (or at least the risk of harmful systemic inflammation developing from normal inflammation).
Systemic Inflammatory Response Syndrome Score
There’s the systemic inflammatory response syndrome, which is incredibly serious and has four criteria. If you have two or more of them at once, congratulations: you qualify – and should probably see a health professional immediately. This isn’t relevant for low-grade systemic inflammation, like the kind associated with obesity or autoimmune disease.
- Body temperature less than 96.8 F (36 C) or greater than 100.4 F (38 C).
- Heart rate above 90 beats per minute.
- High respiratory rate, 20 breaths per minute or higher.
- White blood cell count fewer than 4000 cells/mm³ or greater than 12,000 cells/mm³.
Of these objective markers to test, I’d lean toward CRP and one of the omega-3 tests. CRP is pretty comprehensive, and, while omega-3 tissue or blood cell content doesn’t necessarily indicate the existence of systemic inflammation in your body, it does indicate the severity of the inflammatory response you can expect your body to have. Taken together, both tests will give you an idea of where you stand.
And now, some subjective markers that I’ve picked up on over the years. These are a few signs and symptoms to watch out for. They may be harmless artifacts, but they may indicate that something systemic is going on.
Flare-up of Autoimmune Conditions You Haven’t Heard from in Ages
Sore joints, dry, patchy, and/or red skin, and anything else that indicates a flare-up. For me, this is usually mild arthritis .
As we discussed last time, acute inflammation is often characterized by swelling at the site of injury. The same effect seems to occur in states of systemic inflammation, although they aren’t localized, but rather generalized.
If you feel stressed, you’re probably inflamed. I’m talking about the kind that has you rubbing your temples, face palming, sighing every couple minutes, and pinching the space between your eyes very, very hard.
Persistent But Unexplained Nasal Congestion
Could be allergies, sure, but I’ve always noticed that when I’m under a lot of stress and generally in an inflamed state, my nose gets clogged. Certain foods will trigger this, too, and I think it can all be linked to a persistent but subtle state of inflammation.
If you fit the bill for the eight signs of overtraining  listed in this post, you’re probably inflamed.
Ultimately, though? It comes down to the simple question you must ask yourself: how do you feel?
I mean, this seems like an obvious marker, but a lot of people ignore it in pursuit of numbers. If you feel run down, lethargic, unhappy, your workouts are suffering, you struggle to get out of bed, you’re putting on a little extra weight around the waist, sex isn’t as interesting, etc., etc., etc., you may be suffering from some manner of systemic, low-grade inflammation. Conversely, if you’re full of energy, generally pleased and/or content with life, killing it in the gym, bounding out of bed , lean as ever  or on your way there, and your sex drive  is powerful and age appropriate, you’re probably good.
And really, isn’t that the most important health marker of all?
Anyway, I hope this was helpful. Systemic inflammation is a pretty nebulous state, and pinning it down can be tough, even with the help of actual objective lab markers. And because inflammation and all the maladies associated with it are so intertwined and feed off each other and have so many different effects, we often feel helpless. Well, try not to pile too much on your shoulders. Get some markers tested if you can, but ultimately it’s going to come down to eating better , moving better , sleeping better , relaxing better , and avoiding too much stress . And if you feel great, I wouldn’t really worry. Don’t be the guy or gal who chases “inflammation,” and don’t go looking for a drug that reduces the liver’s production of CRP. Instead, be the one who eliminates the ultimate cause, or causes (because there are always more than one) of the chronic inflammation. Revisit the list from the end of the last inflammation post  and make sure you’re not omitting anything that you should be including or including anything that you should be omitting.
Take care and be sure to leave a comment! How do you tell if you’re in a state of low-grade inflammation?