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Our Body is not Communist: Competition and those Aggressive Fat Cells

September 21, 2005 09:39 AM

In my previous post, I tried to show that cell colonies execute their own programs; programs that aid their survival and reproduction within the body. There is real competition in the body for resources; it is not some planned central economy where each type of cell gets exactly what would be best for the overall health of the body. The view that the body is in harmony and homeostasis is one of the last vestiges of the central planning thesis that sees a coordinated order as the result of centalized, rational direction.

The central planning thesis of order used to be invoked in attempts to understand the operation of the brain. It had been crudely modeled as a centralized system in which the "little man" or humonculus sat somewhere inside the brain and directed its actions. That naive view is gone, though it seems to be part of folk psychology even now because people tend to attribute an organized process to an organizer. Naive religions cling to this view when they attribute the order that seems to exist in the world a prime or centralized Mover.

The same thesis underlies a belief that centrally planned economies are somehow better than decentralized ones. If only someone were in charge so they could direct resources to where they are most "needed" the resulting allocation would produce the social optimum. "From each according to his ability and to each according to his need" was the allocation goal communism purported to attain. The problem was it never happened; every communist society we know of allocated resources to a privileged few and all but a few have collapsed.

We are lucky the body is not a planned economy or we wouldn't be alive for long.

In my post, I made the argument that every cell in the body is a self-interested agent, executing its dna program. This is a "tough" program that puts the cell's survival and reproduction first. It could not be otherwise for these cells are derived from primordial organisms programmed to live on their own. Multicellular organisms formed when individual cells accumulated into groups that somehow coordinated their actions. The difference between a collection of individual cells, like slime mold, and a multicellular organism it that, in the latter, the cells specialize their function. Since multicellular organization permits specialization, a multicellular creature has advantages over mere aggregations of like cells. Thus, we can have a liver or eyes whereas slime mold must get by with the restricted facilities available to identical, single, non-specialized cells.

Adam Smith said it all when he told us of the division and specialization of labor and how self interest sustained the coordination among agents, or cells in this case. He could have been the first modern biologist had he turned his great mind to this problem. The discovery of stem cells, those little undifferentiated cells that can turn into just about any kind of cell if they are put in the right neighborhood where they get that important local information from the cells around them, is a compelling proof of the decentalized organization of cellular specialization and coordination.

It appears that a stem cell with the same dna program as every other cell can become a heart cell or an eye cell or a pancreas cell if it is put where its neighbors are heart cells, or eye cells, or pancreas cells. Its all in the neighborhood because the common-to-all dna program is executed under local signals from neighboring cells. A liver cell is no closer to other liver cells than it is to heart cells in gene space, but its dna program is executed from local signals which makes it a liver cell. So, it becomes specialized.

Which brings us back to those fat cells. If the body were a communist, cells would not take more than their "share" somehow determined to be in the best interests of the body. But, they really are self-interested to the point of ruthlessness. They don't care about the harmony of the body or maintaining homeostasis, they care about themselves because that is how evolution programmed them. Its in their dna and the same holds true of all the other cells.

When the body is in chronic positive caloric balance, fat cells grow and proliferate. Its a good thing that they do because it would be dangerous to have excess nutrients constantly circulating in the body. We would have so many free radical reactions that we would die. And our kidneys and livers would quickly fail. If many fat cells simultaineously were to execute their apoptosis program, die and release their contents, it could kill us. So, fat is good up to a point, when we are in chronic positive energy balance.

The problem is when the colony gets to be so large that its mass action and self-interest directs a larger proportion of our total resources to fat. I detailed how that happens in the last post.

There are two strategies for attacking the problem: 1. eliminate the chronic positive energy balance by taking in less energy and expending more energy, and 2. shifting the allocation of resources from fat to the other organs and muscle.

This is easy to do, but the fat cells won't go willingly and you don't want them to release their contents massively because it would be toxic. Change the energy balance by eating less energy dense foods, eating less in total, and by being more active. Walking is part of this, but a small part. It doesn't burn much energy and it doesn't alter the hormone drives that direct energy to fat and the other organs sufficiently. To change the hormone drives you must eat intermittently, eat foods that do not release a strong insulin signal, and you must exercise with enough intensity.

This is easy to do too, but you have to ignore the signals out there in the external world that put choices before us that our brains and bodies never faced before and for which they may have inadequate defenses.

· Evolutionary Fitness

Comments

Posted by: outsider [TypeKey Profile Page] at May 17, 2007 1:27 PM

Posted by: Flower Online [TypeKey Profile Page] at September 12, 2006 2:14 AM

I'm afraid it looks to me like the article is relating two things that I'm not convinced are definitively related, namely a notion of central control and that optimizing wrt a specified objective function and constraints fails when the "real" objective function and constraints starts to be changed. To take an example in the UK health system, all the "planning/action" is essentially decentralised down to the level of individual hospitals. However, the "objectives"/"targets" (waiting list statistics, etc) are all imposed from central government. It's entirely plausible that the same "concrete actions" would be taken if control came from central government as well. But there're complaints that the interests of patients are disadvantaged because the targets, being global and simplified do not encourage the careful analysis and balancing of local circumstances. So there's a problem that arises not from lack of freedom of action -- there is no comeback to hospitals regarding the actions they take -- but because the objective's they are tasked & rewarded for acheiving are misleading. Similarly, I make my living writing computer programs to try and solve machine learning tasks. I both write full programs myself with what you'd call "full central planning" and I've experimented with genetic algorithms, which are closer to decentralised approaches. And almost always the reason for poor results when used in the real world isn't the difference between the two ways of doing things, it's because the abstracted, simplified objective function used to model the problem during development is a poor approximation of the objective function that actually applies in reality. (I'm not disputing that decentralised as opposed to central planning may be different in many important ways, just that it seems to be less relevant when the objective being "planned against" isn't the objective being used in reality.)

Likewise, I can't see how you can say that teh decentralised as opposed to collectivist nature of cells is a particular issue, as opposed ot the fact that the objective fn they attempt to optimise and the implicit environmental constraints "they assume" simply aren't the right ones for the modern world. To put it another way: you're essentially claiming that, given knowledge of the conditions that applied over most of human evolutionary history (and not foreknowledge of what conditions apply now), a central design would have produced a human where the various cells behaved differently from the "design" resulting from decentralised behaviour, so that their collective behaviour would be more beneficial to the being as a whole (for the conditions at that time). I'd be surprised if you believed
there'd be such a better behaviour (without foreknowledge of the conditions that apply now)

The point that the various feedback mechanisms in the body are vulnerable to the fact that the objective and implicit constraints are very different from what evolution has programmed into them is well taken though.

Posted by: david tweed [TypeKey Profile Page] at September 21, 2005 11:54 PM

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