Is Fructose Bad For You?

fructose-ratUCLA researchers have concluded that this is at least the case for ratsRight off the bat, there are two really good arguments against the idea that fructose is dangerous: 1) most of us aren’t rats, and 2) fructose is found in nature.

The researchers found that fructose alters genes found in the brain, and that these link to a variety of diseases. Here is the link to that story.

Interestingly, there appears to be an antidote: omega-3 oil. The UCLA researchers found that omega-3 oil reversed the damage to the brain genes.

Who eats what?

Let’s compare our diet to our direct ancestors: the hunter-gatherers. There are two flashing red lights here. They got a lot more omega-3 that we get, and they consumed a lot less fructose. So should the above rat research turn out to apply to humans, it may well be that in our million years of evolution, we were never in danger from fructose consumption because we got a lot of omega-3 and very little fructose.

fructose-fruitOmega-3 is found in grass fed meat primarily. Obviously hunter-gatherers ate grass fed meat. It may have been dead for a week when they got it, but it was grass fed. At the same time, the only source of fructose would have been fruit. This would have been seasonal for most, and typically, wild fruit is much smaller.

The Western diet is awash in fructose.

We have access to a lot more fruit, and every year the fruit seems to mutate to larger sizes. But this isn’t the real problem. Refined sugar, unavailable in hunter-gatherer societies, is 50% fructose. But even that isn’t the worst source.

In the 70s, there was a realization that excess circulating glucose was at the root of many diseases. The ever-vigilant food industry saw an existential threat and thus was born high-fructose corn syrup. Fructose isn’t glucose, and so it therefore must be better, so reasoned the food-industry marketing departments, and it could be made very cheaply from corn, so more profit. A win-win, at least from the food industry’s point of view. So into the Western diet went high fructose corn syrup. In the U.S., the annual average consumption per family is around 200 pounds, but for many it’s two to three times higher. (Pause for a moment and ask: how is that even possible? Yet it is true.)

So once again the Western diet pushed the nutrient ratios way out of kilter. This is always bad, and we know we are in the midst of a decades long degenerative disease epidemic largely caused by our own lifestyle. (An epidemic so enduring we now consider it normal and inevitable.)

Our “normal” diseases are heart disease, cancer, adult onset diabetes, Alzheimer’s, etc. At least 70% of us die from these. However, these diseases are all but unknown among hunter-gatherers. We don’t have to be getting them either.

What is fructose anyway?


Good sugar —— Bad sugar ?

The two predominant sugars are glucose and fructose. The body metabolizes glucose, and, from an energy point of view, could live on it, although this wouldn’t be ideal. Glucose has six sides, fructose five.

The body doesn’t seem to like fructose.

The body goes to a lot of trouble to keep fructose out of circulation. There has to be a good reason for this, and the UCLA research may shedding light on this. Dietary fructose first appears in the liver. The liver converts almost all of it to glycogen, a concentrated form of glucose. Any excess will go into circulation, but at a concentration far lower than glucose. And within a short period that is gone too.

This glycogen is our energy store. The liver uses it to keep our circulating glucose up, and muscles store glycogen for energy purposes. The fact that the liver prefers fructose to glucose when topping up its glycogen unravels the grand food industry notion that eating fructose would reduce glucose. In effect, the liver completely cancels out any such effect. The net effect is that high fructose causes high glucose. So no help there, and with the evidence that fructose may carry its own dangers, we clearly can’t be too optimistic.

Further research will sort this out.

Be prepared for some anti-research from the food industry should the dangers of fructose become mainstream.


Hunter-gatherer nutrition manual

For those of us unwilling to wait for the rat research to progress to humans, it would probably be safe to try to follow our hunter-gatherer ancestor’s lead. This would mean fructose from fruit only, and prudent amounts at that, no added sugar, and certainly no high-fructose corn syrup. Plus, more omega-3 foods in the diet too. Omega-3 comes from grass fed meat, oily fish, and various other sources.


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