I stumbled across a Horizon programme on friday night on BBC2 called Fat Vs Sugar, and it displayed all the signs of being the kind of pop-science I can’t watch : I find their shallow agenda, narrow focus, and monumental lack of content (padded with 50 minutes of repetition, smarmy camera angles, and tight levis) all too infuriating.
However, I happened to switch back to this programme as they were starting to draw conclusions from the experiments they’d run. I am always interested in scientific data, as long as it is taken within the context it is set, so my interest was sustained for a while.
The premise was that two identical twins, both medical doctors (though that only gives the programme merit, not really the science) were to go on fundamentally different diets – one high in fat, the other high in sugars, and see what happens to their bodies, supposedly built from identical genes (ignoring epigenetics, individualised health histories etc.)
After a month, they were surprised to find that the high-sugar diet had increased his insulin production, but he retained a surprising level of stamina in endurance tests. No surprise there really, given that we are built to run on sugars – see article on our co-evolution with fruit sugars here.
Insulin and Sugars
Surely they should have been expecting high insulin levels, as it is this increased insulin-production in response to refined sugars that eventually exhausts the pancreas, and leads to the insulin failure known as diabetes.
As sugars are being forced into cells to keep the blood-sugar levels tolerable, rather than because the cells are calling for the sugars, these sugar-bloated cells can repackage the sugars as solid fats, and dump them back into the blood, where they don’t antagonise blood-sugar levels anymore, but do add to the fat-saturation levels of the blood and liver. These excess fats then get in the way of further insulation secretions, and lead to the diabetic phenomena found in a purely high-fat diet.
Insulin and Fats
To their surprise, the high fat diet had even higher levels of serum insulin than his sugary counterpart. This is because his system was trying to get the insulin through fat-saturated blood – a situation known to be as much a part of insulin elevation and inevitable pancreatic failure as a high sugar diet, so no news there either.
At the end of the programme they went on to look at the surprising connections found in rats (though tenuous due to the species difference) around their diet-regulating habits regarding fats & sugars.
Captive rats can exist happily on a high fat diet, and do not show outward symptoms we associate to humans on such diets – IE; become obese or suffer coronary issues. And likewise on a high sugar diet.
But when fats and sugars are combined, in an irresistible concoction, all restraint goes out the window, and they gorge themselves to death – literally.
Notably this combination of high-sugar & high-fat exists nowhere in nature, so their systems have not had any evolutionary precedent to learn how to manage it.
Unlike with rats, there are plenty of high-sugar food examples in our lineage – in fact you could almost say that our 120 million years on a high-sugar, low-fat, fruit-rich diet defined apes as a creature separate from the rest of the mammals.
However, even in this deliberately evolved, high-nourishment environment we do not find high-fat AND high-sugar snacks. See the top fruits here
Actually, it is easy to leave the rats out of it, and simple look at which NATURAL foods humans are attracted to – that’s without preparing, mixing, cooking, peeling, or grinding the food at all. Can you think of ANYTHING aside from fruit that really grabs you by the tastebuds ?
And yet, there are no obese apes. Not one with diabetes. Nor hyperglycemia. And the dentistry-profession among the higher apes is notably lacking (or in any other animal for that matter !). Check out article on calcium saturation and distribution here.
In fact all this has only come about since we started refining sugars into sugar, and fats into fat. And then mixing the two – ultimately to make palatable (and therefore saleable) large amounts of cheap, filling, storable grains.
Aside from stimulants like chocolate, tea and coffee, where else do we mix sugars and fats ?
Feel free to comment your answers below.