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NATURE runs clinical trial recruitment, Free Feeding Sugar, Phase 4, genetic response and mortality

TRIAL: A test to determine whether the species will create new organ designs to accommodate chronic over feeding or fail and result in mortality and long term decline.  The alternate endpoint, increased intelligence in feeding strategies.


The test subjects all like sugar but dietary advice mostly says give it up.  The question, what really happens when they eat excess sugar over time?

OK, but sugar is glucose and it is known that glucose is a fundamental fuel so what is wrong with that? Let's take a walk down bio-chemistry lane.  Just a peak so easy peasy. This is really important if one has concerns about livers so don't run away yet.


First, sugar is not glucose.  Sugar is a marketing term.  It is actually two sugars that are joined together with a weak bond.  One is the familiar glucose, the other is the mysterious fructose.  The combination is called sucrose but we all love it as sugar.  Surprisingly both of these have exactly the same chemical formula and are 6 carbon chain molecules.

Details shortly but an interesting factoid is that glucose is barely sweet.  What you taste is mostly fructose when you eat sugar.  On the sweetness scale glucose is a 75 but fructose is 175.  This isn't important to the chemistry but tells you something about food marketing.  Take a look at how the 6 carbon molecules are actually connected, that is the key to the mystery.


No need to go into the details, but that small difference at one end means that these almost identical molecules participate in different chemical reactions.  In this case it means that after the bowel breaks them apart, glucose can circulate freely in the blood but fructose will be trapped by the liver.  Glucose is available as fuel directly but fructose will be converted mostly to triglycerides by the liver and can overload it with fat.  Too much glucose carries its own problems but this is why excess sugar is particularly bad for your liver.  See, it is simple really.

OK, but why does everyone say to eat fruit? That is full of sugar.  I love this question.  All of the experts have punted that and just say that because the fruit is natural all of the other values in the fruit make it OK to eat. It turns out that ain't necessarily so. Remember, you are the transport system the bowel has constructed over eons to deliver food to it.  The bowel is very wise and it always knew that fructose was a potential problem so it built in the ability to convert fructose into glucose in the small intestine before it enters the bloodstream. If the science interests you here is a link to the study.

OK, problem solved.  We like sugar but as food it is hard to get, right?  Well that was true earlier but in the past 200 years the consumption of sugar has increased about 100 times.  The lesson, if you eat fruit like you are supposed to and don't go crazy with sugar your bowel will be happy with you.  The bowel made a mistake in design, however, and didn't provide a stop signal when too much fructose was coming in.  A bug in the system if you would like to think of it in modern language so consuming more fructose than the system can manage is easy to do.


Sometimes we step back a bit and look at the world more broadly.  Consider that nature cares not at all about you individually.  We have a fierce attachment to ourselves but nature built a very sophisticated body over a few million years and we have recently been running an experiment to see if over feeding is harmful.  We have assembled a test group who practice obesity and there is a control group who do not.  It is a fairly long experiment from our perspective but nature isn't bothered by time. Rather like researchers with their mice, just as an analogy.

So we have a free feeding experiment where nature will learn whether the bowel will build an organ able to handle lots of fructose without failing or will the test group fail to thrive.  It is an interesting test because it is also an intelligence test.  It is studying whether the obese group will choose to modify its feeding strategy in the event that the practice is harmful.  If not that group will eventually be sacrificed.  Their deaths will be humane we hope but the fate of failed experiments is usually not a kind one.  The alternative endpoint may be that evolution creates a design that can process excessive sugar successfully. Like any good researcher nature cares not that a test fails as it moves the field along in the process of finding a better way.  Some of the individual bowel transporters do have strong feelings about being in the bad part of the test but research sacrifices test subjects routinely so nature can't really be too concerned with those individual views.

This particular clinical trial is in its early signup stages.  We currently have about a 30% participation in the obese group.  Ideally we would like to see a 50/50 split.  Of course, it is still possible to withdraw from the study. No one is required to be part of the obese test group. Since it is a free feeding model all you have to do is not participate.  Your decision will ultimately be recorded in the mortality data.

Nature thanks you for your participation.