Metabolic Syndrome: There is a modern problem with obesity. Despite the fact that a significant number of children in the world are undernourished, in rich countries there is a significant and increasing number who are obese to the point that it is a health hazard. This is commonly blamed on the availability of rich, cheap food and on the fact that many things that used to require physical effort, such as traveling, playing games and earning a living, have been made physically very easy so we do not burn up as many calories as we used to going about our business. And I do not deny that these things contribute. But I suspect there is more to it than that.
For one thing, it appears to be a continuation of a trend that began long before obesity was a problem. In about the 1950’s and extending into the 1960’s America seemed to be on a trend of producing giants. Men who once would have seemed to be normal were now dwarfed by their towering friends. It was only when the trend toward greater height ceased that the trend toward obesity began to appear. At least so it seemed at the time. Like obesity, greater height was attributed to better nutrition.
But there are hints that something has been overlooked. For one thing, we have small statues of women that go back thousands of years. Ceramics were developed for making these statues. It was not until a long time later than the Ainu of Japan began to use ceramics to make dishes. So the statues clearly were of great importance to people at the time. They have been called fertility symbols, and so it may be. But the point at present is what they looked like. They were fat.
In the 1950’s they were commonly described as having, “Exaggerated breasts and thighs, proving that they were created for symbolic or ritual purposes.” One does not hear that any longer. At present, a glance will assure you that these are quite realistic images of perfectly normal fat women. Indeed, they usually do not have faces, so their symbolic meaning was probably real. But otherwise they were just obese.
So how did these ancient artists no what obese women should look like? Probably they had seen obese women. So obesity was a Neolithic problem as well. But this time it cannot have been due to fast foods and video games. It cannot have been due to doing all traveling in motorized vehicles or having the laundry done by machine. So something is missing. I believe that they were made, or at least invented, in a society in which infertility and obesity occurred at the same time, just as they are occurring together now. These were societies that had failed to maintain their gene pools at a size small enough to permit them to survive.
Hybrid vigor is above question. I have ridden many kinds of horses and have always enjoyed doing so. But once I rode a mule from the bottom of Yosemite Valley to the rim. They explained to us that the climb was too strenuous for a horse. And that mule was like no horse I had ever ridden. It was not as big as a draft horse nor as swift and gentle as a Florida cracker horse, but it just felt solid. It felt sturdy. It made you feel that everything was under complete control, Vigor was an understatement. The animal was amazing.
You do not have to go to the degree of gene mixing that will result in a mule to get the equivalent of hybrid vigor. The Danish study cited on the Main Page of this site demonstrates that even increasing the distance between the birthplaces of a couple by a few miles is enough to produce an increase in the number of children in the first generation. Those couples are enjoying the fleeting blessing of hybrid vigor.
So increased height and in later years increased weight seem to be simply hybrid vigor in action as we have made our gene pools ever larger and more diverse. So why should mixing genes make you fat? And for that matter, why should obesity be related to diabetes and hypertension, all of which seem to occur together in what is now called the metabolic syndrome?
Reflect that obesity can kill you. Starvation can kill you too, and generally a lot faster. If your ideal weight is 170 pounds, you might be able to survive for a while at a weight of 240 or more. Dropping to 100 pounds and below, would probably be a worse health problem. Diabetes, high blood sugar, can kill you, but low blood sugar will kill you faster. If 100 is a good blood sugar, then 200 is too high, but you might hardly notice it for a while. A blood sugar of zero would finish you off at once. If 120/80 mm Hg is a good blood pressure, you would be in a state of emergency if it rose to 240/160. 0/0 would mean you were already dead.
So all three components of the metabolic syndrome have this in common: they are bad but probably not so bad as the reverse.
If a system is evolving that is trying to maintain itself in a good homeostatic balance between to deadly extremes, one would expect it to have more robust defenses against the swift killer than against the slow one. The fine tuning that controls the level of blood sugar, blood pressure and intake of nutrition is not symmetrical. It will respond more dramatically to a challenge in one direction than another.
Well and good. So we are equipped to survive many kinds of challenge. Then stir the gene pool up, mixing genes and control signals from different sources. Look what happens to blood sugar as the genes get scrambled. Some of the mismatches of tuning will tend to drive the blood sugar down. Others will tend to elevate it. But since the systems that support blood sugar are more vigorous than those that limit it, the net effect if there is a problem will usually be to raise the blood sugar.
The same logic holds for nutrition and for blood pressure. In other words, accepting as I propose that starvation is worse than obesity, shock worse than hypertension and hypoglycemia worse than diabetes, then the metabolic syndrome is predictable any time the gene pool size gets out of hand, as it probably did in Neolithic times too.
We should have known this would happen. The only way it could not happen would be that evolution never occurred AND we were designed by a total incompetent. I confess I have had my moments of doubt, but in all my life I have never heard anyone seriously maintain both of those notions.
Like so many things, this theory can be tested. Again, we could turn to the Iceland study. I do not know whether they have a significant problem with metabolic syndrome like so many other rich countries, but if they do it would be very simple to count up a bunch of obese people and an age matched bunch of lean people and then use the work they have already done on relatedness and fertility and to see if there was a correlation between metabolic syndrome and a low degree of relatedness.
The problem is so important and the study would be so easy that it is hard to imagine it not happening.
But maybe metabolic syndrome does not occur in Iceland. Since they are the most homogenous population in the world, that would already be a clue. Otherwise, someone ought to undertake the serious and difficult task of making the same comparison in a rich, fat society with incomplete genealogical records.
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