What is inflammation?

December 9, 2011 11:14 AM

What is this "inflammation" of which they speak? Is it, you know, a real thing?

Paleo types talk about how diabetes, cancer, etc come from "inflammation". Do they really? What is "inflammation" in this sense? Various nutrition and calorie websites will tell you if a food is "inflammatory" or not, but there seems to be disagreement among sites about which and how much. Again, is this a real thing? I am perfectly willing to believe it, but there seems to be a lot of unclarity and handwaving out there.

I would love resources that are not from paleo writers or websites - while I am completely down with the whole "as few processed foods as possible, lots of protein and make like a tiger is chasing you from time to time" approach because it's obviously way healthier than the average US way of life, I would like something more NIH-ish, peer-reviewed, etc.

posted by Frowner to food & drink (22 answers total)

I noticed the same weird increase in that word that you did. I asked an open-minded doctor friend about it a couple of months ago, and her summary was:

"It's a magic word that means what 'toxins' meant twenty years ago."

So, yeah. Handwaving trumping science.
posted by rokusan at 11:16 AM on December 9, 2011 [8 favorites]

See Also. Really close to the same question from just a little while ago.
posted by Blake at 11:16 AM on December 9, 2011

Here's an interesting thread from the blue about the inflammation theory of depression.
posted by sharkfu at 11:18 AM on December 9, 2011

See Also. Really close to the same question from just a little while ago.

That's actually what inspired me to ask this question - I wanted some non-ideological info about the question of health and inflammation - it seems to me that paleo folks have a lot of kneejerk biases about this stuff, but then a lot of folks hear "agriculture made us less healthy" and produce equally dubious counter-arguments.

End threadsit!
posted by Frowner at 11:20 AM on December 9, 2011

... inflammation as a process appears to be real. On the other hand, it is also the paleo sphere's vacuous equivalent to "toxins" as found in previous trendy health theories.
posted by rr at 11:21 AM on December 9, 2011 [1 favorite]

My post to the other ask thread links to Loren Cordain's published-in-peer-reviewed-journals work, which, while being hosted on a paleo site for ease of access, does fit your criteria.
posted by bfranklin at 11:25 AM on December 9, 2011

Inflammation is a very real physiological phenomenon that we understand pretty well on the cellular and molecular level. The Wikipedia article isn't bad.
posted by mr_roboto at 11:29 AM on December 9, 2011 [3 favorites]

diabetes, cancer, etc come from "inflammation". Do they really? What is "inflammation" in this sense?

These conditions can involve the "inflammatory response". I believe most people think of inflammation as swelling or redness, and in that sense, it's hard to understand what that has to do with diabetes and cancer, etc. but in reality, the inflammatory response is a signaling cascade in cells and the body, which may result in observed swelling or redness (or it may not). I agree the Wikipedia article is a good starting point, especially as pertains to disorders you ask about:
http://en.wikipedia.org/wiki/Inflammation#Inflammatory_disorders
posted by Tandem Affinity at 11:33 AM on December 9, 2011 [4 favorites]

There was a similar post yesterday discussing inflammation and acne where an MD and a PhD who research inflammation chimed in about the supposed inflammation/diet links.
posted by TungstenChef at 11:34 AM on December 9, 2011

Center for Science in the Public Interest:

Several good science-y types in there

"Inflammation plays two key roles in coronary heart disease," explains Penny Kris-Etherton of Pennsylvania State University.

and

Heart disease, cancer, Alzheimer’s disease, the metabolic syndrome, physical disability. That’s just a partial list of the illnesses that have been linked to chronic inflammation.

"It’s different from the classic, red, swelling, white-cell kind of inflammation that we’re used to thinking of," explains Walter Willett, chair of the Nutrition Department at the Harvard School of Public Health.

posted by A Terrible Llama at 11:35 AM on December 9, 2011 [1 favorite]

So, yeah. Handwaving trumping science.

This could not be further from the truth, unless you have a very idiosyncratic definition of "science." I just did a search in Pubmed restricted to "diabetes" and "inflammation" in the title field alone and got 432 hits. See, for example, this abstract: Pathophysiological implications between chronic inflammation and the development of diabetes and obesity. Paleo diets and inflammatory foods are another story altogether and there well may be a lot of pseudoscience involved in their discussion, but there is indeed a lot of current scientific interest and research on the role of inflammation in chronic disease.
posted by Wordwoman at 1:34 PM on December 9, 2011 [2 favorites]

My favorite sites for this are PubMed (from our friends at the NIH) and the Public Library of Science.

A search for inflammation and diabetes at plos.org turns up hundreds of results, including Inflammation, Insulin Resistance, and Diabetes—Mendelian Randomization Using CRP Haplotypes Points Upstream and Differential White Blood Cell Count and Type 2 Diabetes: Systematic Review and Meta-Analysis of Cross-Sectional and Prospective Studies; the latter's Objective says,

"Biological evidence suggests that inflammation might induce type 2 diabetes (T2D), and epidemiological studies have shown an association between higher white blood cell count (WBC) and T2D. However, the association has not been systematically investigated."

A PubMed search for inflammation and diabetes turns up thousands of articles, including Inflammation, Insulin Resistance, and Diabetes—Mendelian Randomization Using CRP Haplotypes Points Upstream (oh look, it's a PLoS article), Lipids Versus Glucose in Inflammation and the Pathogenesis of Macrovascular Disease in Diabetes, and Inflammation and the Incidence of Type 2 Diabetes. The Objective for the last one says:

Many studies have documented associations between inflammation and type 2 diabetes incidence. We assessed potential variability in this association in the major U.S. racial/ethnic groups.

(Honestly, I was typing and cutting and pasting while Wordwoman answered above. PubMed is a great resource.)
posted by kristi at 1:42 PM on December 9, 2011

It's a magic word that means what 'toxins' meant twenty years ago."

I'm surprised to learn that intelligent and otherwise well-informed people hold this opinion.

Inflammation is a real biological phenomenon, and chronic inflammation has been repeatedly linked to various diseases, including heart disease, diabetes, arthritis, alzheimer's, multiple cancers, fibromyalgia, etc.

"It’s different from the classic, red, swelling, white-cell kind of inflammation that we’re used to thinking of," explains Walter Willett...

But not entirely different, as I understand it. Sunburn is, in fact, similar to the kind of inflammation that is linked to disease. Chronic inflammation (when it just goes on and on and on) puts your inflamed tissues in an accelerated state of cell death and division, which might help explain the possible cancer link.

Really, the wikipedia article on inflammation should clear this up for anyone who has doubts.
posted by General Tonic at 1:47 PM on December 9, 2011

Yeah inflammation is totally real. I myself suffer from a disease (colitis, yuck) that involves an unwarranted inflammatory response in my intestine. The term has been co-opted by some woo-woo pseudo-medical types, but is nonetheless totally real. Not just for stomach stuff, either, rheumatoid arthritis is inflammatory, and the list goes on. It's real.
posted by smoke at 1:58 PM on December 9, 2011

I think rr is on point here. It's a real thing, but as co-opted by the paleo/whoever people it's a meaningless term.

I'm currently following some dieting advice from a weight-loss threat on the green from years back which suggested following the "Velocity Diet" but using other brand's product for price savings. In the course of reading their website (and many others) I discovered that there's a LOOOOOTTTTTT of very strident claims about their exact product and the exact combination of things they put in it is somehow the magic solution and The One Right Way. Rather than acknowledging that they'll shilling a high-protein low-carb low-fat product and some metabolic simulators and vitamin powders.

Paleo seems from my reading to be less profit-motivated in this but subject to the same sort of absolute thinking. There may be some relationships there and things that contribute to or decrease susceptibility but I question "inflammatory" as a useful concept. Bodies seem far too complicated and resilient to talk in these absolutes rather than patterns and proportions of healthy diets.
posted by phearlez at 2:16 PM on December 9, 2011

Right, it should be clear that "inflammation" is totally real and can be both a symptom and cause of disease.

However, the idea that inflammation is *caused* by a non-paleo diet is pretty nonsensical. There are exceptions for people with various food allergies, gluten problems, what-have-you, but in general, food doesn't directly cause inflammation. A poor diet can lead to metabolic issues and then to disease such as diabetes, but it's not like you can just add up "inflammation" in food the way you would use caloric counts.
posted by tau_ceti at 2:41 PM on December 9, 2011 [1 favorite]

I think rr is on point here. It's a real thing, but as co-opted by the paleo/whoever people it's a meaningless term.

Likewise, the co-opting of the term "toxins" does not invalidate the scientific concept of toxicity.
posted by desuetude at 2:51 PM on December 9, 2011 [1 favorite]

I didn't mean to suggest that inflammation itself is fictional, and I'm quite sure that's not what the MD I quoted meant, either. No more than toxins are.

Of course inflammation exists and comes along with many ailments, as others have said. It's the use of it as smoke ("quasimedical-term is the secret cause of all serious disease!") that is handwaving nonsense.
posted by rokusan at 4:10 PM on December 9, 2011

In terms of inflammation causing cancer, this is true; anything that causes an increased rate of cell division will increase your cancer risk, because any time a cell divides there is a chance of a mutation, and some of those mutations will be harmful. Asbestos, for example, physixally lodges in the lungs, and the cells around it become inflamed as they try to heal around it; this increased cell division over time can cause cancer. This is also why stomach ulcers can cause stomach cancer, and so forth. It is a very real/true/whatever thing. You can read The Emperor of All Maladies, an excellent book on cancer, for more information.

Inflammation causing cancer confuses people because they sometimes have an idea that it has to be a chemical reaction -- mutagenic chemicals do cause mutations and that is why some elements of tobacco or pollution or pesticides or anything else cause cancer -- or genetic -- all cancer is genetic in a matter of speaking because it's a change to the DNA, but some people are born with some mutations and others acquire them later. Cancer can also be carried by viruses, which copy the mutation into the host (or FROM the host to transmit elsewhere), bacteria if they cause inflammation or produce mutagenic toxins, etc. Rays of energy (from the sun, from radiation, etc) can cause cancer by damaging DNA. Cancer is caused by a ton of things, *anything* that causes cell division or mutations, including just living and having terrible luck with the normal and necessary cell divisions -- and yes, including inflammation.
posted by Nattie at 7:16 PM on December 9, 2011 [2 favorites]

For the record I never said inflammation was fictional but rather that the paleo sphere is taking a legitimate concept and repurposing it. One gander at paleohacks should illustrate the problem.
posted by rr at 11:22 AM on December 10, 2011

For the record I never said inflammation was fictional but rather that the paleo sphere is taking a legitimate concept and repurposing it.

My intention was just to offer another illustrative example, btw, not intimating that you were an inflammation-denier.
posted by desuetude at 4:10 PM on December 10, 2011

In case you're still checking the thread, I just came across this link between inflammation and insulin resistance, chock-full of links to journal articles.
posted by kristi at 7:55 PM on December 21, 2011