Wednesday, September 22, 2010

Low nonexercise activity thermogenesis: Uncooperative genes or comfy furniture?

The degree of nonexercise activity thermogenesis (NEAT) seems to a major factor influencing the amount of fat gained or lost by an individual. It also seems to be strongly influenced by genetics, because NEAT is largely due to involuntary activities like fidgeting.

But why should this be?

The degree to which different individuals will develop diseases of civilization in response to consumption of refined carbohydrate-rich foods can also be seen as influenced by genetics. After all, there are many people who eat those foods and are thin and healthy, and that appears to be in part a family trait. But whether we consume those products or not is largely within our control.

So, it is quite possible that NEAT is influenced by genetics, but the fact that NEAT is low in so many people should be a red flag. In the same way that the fact that so many people who eat refined carbohydrate-rich foods are obese should be a red flag. Moreover, modern isolated hunter-gatherers tend to have low levels of body fat. Given the importance of NEAT for body fat regulation, it is not unreasonable to assume that NEAT is elevated in hunter-gatherers, compared to modern urbanites. Hunter-gatherers live more like our Paleolithic ancestors than modern urbanites.

True genetic diseases, caused by recent harmful mutations, are usually rare. If low NEAT were truly a genetic “disease”, those with low NEAT should be a small minority. That is not the case. It is more likely that the low NEAT that we see in modern urbanites is due to a maladaptation of our Stone Age body to modern life, in the same way that our Stone Age body is maladapted to the consumption of foods rich in refined grains and seeds.

What could have increased NEAT among our Paleolithic ancestors, and among modern isolated hunter-gatherers?

One thing that comes to mind is lack of comfortable furniture, particularly comfortable chairs (photo below from: prlog.org). It is quite possible that our Paleolithic ancestors invented some rudimentary forms of furniture, but they would have been much less comfortable than modern furniture used in most offices and homes. The padding of comfy office chairs is not very easy to replicate with stones, leaves, wood, or even animal hides. You need engineering to design it; you need industry to produce that kind of thing.


I have been doing a little experiment with myself, where I do things that force me to sit tall and stand while working in my office, instead of sitting back and “relaxing”. Things like putting a pillow on the chair so that I cannot rest my back on it, or placing my computer on an elevated surface so that I am forced to work while standing up. I tend to move a lot more when I do those things, and the movement is largely involuntary. These are small but constant movements, a bit like fidgeting. (It would be interesting to tape myself and actually quantify the amount of movement.)

It seems that one can induce an increase in NEAT, which is largely due to involuntary activities, by doing some voluntary things like placing a pillow on a chair or working while standing up.

Is it possible that the unnaturalness of comfy furniture, and particularly of comfy chairs, is contributing (together with other factors) to not only making us fat but also having low-back problems?

Both obesity and low-back problems are widespread among modern urbanites. Yet, from an evolutionary perspective, they should not be. They likely impaired survival success among our ancestors, and thus impaired their reproductive success. Evolution “gets angry” at these things; over time it wipes them out. In my reading of studies of hunter-gatherers, I don’t recall a single instance in which obesity and low-back problems were described as being widespread.

10 comments:

Scott W said...

I have worked standing up for about 10 years at my desk job. I started when I worked in an office and had some shoulder pain that was aggravated by slouching. My employer at the time thought it was weird but granted my wish.

Once my company allowed me to work from home, I built my own standing desk at the exact height that I had learned worked for me. After years of doing this I have grown completely accustomed to it and would not go back to sitting all day.

It is just so easy to race off and take care of something - instead of having to shove your chair back - that I do it more often. I probably fidget more too I guess.

People are always aghast that I stand all day...and I just say, "you mean like a check-out clerk or a postal worker or a construction worker or..." For some reason people assume that computer workers have to sit on their butts all day or they are punishing themselves somehow.

Scott

Aaron Blaisdell said...

Interesting post, as usual. I must say I have a slightly different slant on fidgeting/energy regulation/thermoregulation. I used to be a typical skinny fidgeter but always ran cold, especially in my extremities. But since ditching the grains/legumes and reducing carbohydrates, I've noticed two things (among many others). a) I don't fidget nearly as much as I used to. b) I don't feel cold nearly as often as I used to. In fact, fell comfortable in shorts and a t-shirt for far longer into the Fall and far earlier into the Spring than ever before in my life. I rarely complain of cold nowadays, despite always complaining about it and bringing a sweatshirt with me everywhere prior to going primal. So I think diet had a huge impact on both my restlessness and my basal thermal condition.

Kindke said...

Although I'm still not convinced about the effect NEAT would have on one's overall body fat levels and fat metabolism, I think comfy chair's are a big cause of lower back problems.

Usually my lower back problems are worse first thing in the morning and depends somewhat on how I've been laying while asleep.

I've noticed that laying down straight and flat on my bed, I get the lower back pain if I let myself completely relax, and it seems to be spurred on by having a large amount of fat tissue around the belly which is being pulled down by gravity and thus deforming the natural concave arch of the lumber spine.

The problem also happens if you have a big bum, the spring of the bed pushes the bum up once again deforming the lumber spine from its natural arc.

Slouching in chairs in another big problem, once again it forces the lumber spine into a convex position.

Ned Kock said...
This comment has been removed by the author.
Ned Kock said...

Hi Aaron.

I don't know if this is your case, but sometimes I hear people say that they they are fidgety when in fact they are a bit anxious. It is a sensation that is associated with stress, is noticeable, and not very healthy. It is also associated with things like increased heart rate.

I wonder if what happened with you was not a reduction in low grade inflammation due to the ditching of grains and seeds. Inflammation causes discomfort at several levels, and anxiety may follow. Perhaps you are feeling more relaxed; a conscious feeling.

Having said that, anxiety-related stress also burns calories, but of the "wrong kind". Since stress is associated with greatly enhanced gluconeogenesis, too high a proportion of the calories burned come from muscle tissue.

The fidgeting associated with NEAT is often not noticed, unless one pays close attention to it.

Ned Kock said...

Hi Kindke.

Good point regarding the unnatural positions and how they create low-back problems.

Another problem with comfy chairs that provide full support for the back is that they weaken the low-back muscles.

Often people who complain about low-back problems for years are "cured" in a matter of weeks by either working while standing up (like Scott), and/or doing strength training with exercises that work the low-back muscles (e.g., good mornings, squats, deadlifts).

But there are a few who injure their low-back further by doing those same exercises wrongly - e.g., with too much weight or poor form.

Aaron Blaisdell said...

Hi Ned,

I'm pretty sure my prior fidgeting was not produced by anxiety, or at least not result in anxiety. Since I was very young, I've always tapped my fingers, rhythmically shake my foot back and forth, etc. Perhaps the inflammation (which is dramatically reduced now that my diet has shifted for the better) was causing some of this. I still tap my fingers a lot, especially when daydreaming or lost in thought (I catch myself at it now and then, not having been aware of it until it pops into consciousness), but the metronome leg (for lack of a better term) has dramatically reduced. Obviously, I may still have higher levels of NEAT than many folks, but since leaning out on the primal diet it's decreased, and I rarely feel cold like I used to, or if I feel it I tolerate it very well.

Ned Kock said...

Hi Scott.

I place a table over my office desk to work standing, and do that often but not all the time. It is a "portable" arrangement; I will upload a picture to a future post.

My impression is that it is not completely natural to stand up for hours, although it is more natural than to sit down in a comfy chair for hours.

Ned Kock said...

Jack C. posted this comment (below) earlier; I think it is relevant for this post.

I should also add that one thing that causes massive muscle loss (net loss of amino acids), almost more than anything else, is physical immobilization of a body part (e.g., a limb).

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Physical inactivity has a powerful effect on suppressing lipoprotein lipase (LPL) activity in skeletal muscle, the rate limiting enzyme for hydrolysis of triglyceride (TG) rich lipoproteins. This, I believe, is a mechanism of self protection to prevent excess free fatty acids that result from TG metabolism from entering the bloodstream.

The result of reduced LPL activity is a sharp drop in TG metabolism which causes a sharp increase in serum TG and increased inflammation.

Increased inflammation results in a decrease in LPL synthesis by the liver which further decreases TG metabolism.

Inflammation also causes increased synthesis of endothelial lipase (EL) by endothelial cells. The preferred substrate of EL is HDL, so serum HDL levels are decreased by increased catabolism by EL.

LDL density pattern was found to be the most accurate lipid indicator of angiographically determined coronary artery disease (CAD). The next most accurate lipid indicator was found to be the ratio TG/HDL-C.

Physcial inactivity increase TG, decreases HDL, and therefore increases ratio of TG/HDL which indictes increase in mass of small dense LDL particles and hence increased risk of CAD, diabetes and obesity.

Apparently, it only takes standing and low grade movements to prevent the complete shutdown of LPL activity and provide marked protection against CAD.

Razwell said...

Hi Ned


I just wanted to let you know that we are not in control of energy balance to a very large degree.


My sources are world renowned scientists Dr. Jeffrey Friedman Ph.D. ( the discoverer of leptin) and Dr. Linda Bacon Ph.D.

Please have a read of my blog, which largely deals with obesity.

razwell.blogspot.com

:)

Take care,
Raz