Another study suggesting fructose is harmful

New study from UCLA:

A range of diseases – from diabetes to cardiovascular disease, and from Alzheimer’s disease to attention deficit hyperactivity disorder – are linked to changes to genes in the brain. A new study by UCLA life scientists has found that hundreds of those genes can be damaged by fructose, a sugar that’s common in the Western diet, in a way that could lead to those diseases.

[Insert sugar industry assurances that it’s just one study, is probably flawed, etc.]

I’m still hoping that Soylent can return to being fructose-free.


From what I heard a long time ago… Fructose isn’t directly harmful/bad… Only in large amounts… I recall something about ratios between fructose and glucose* being a factor. You don’t need a product that is fructose free :sweat_smile: The dose makes the poison is also a saying.

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A serving of 1.5 has less fructose than half an apple.


Has anyone watched this film? it can be found online. Since I started doing my own DIY about 2 months ago for 60% of my diet I have stopped drinking many soda’s a day, stopped eating little debbie snacks every day. I have cut out sooo much and have not really missed it at all.

I looked for a little information regarding all this… something really interesting came up which I never heard about before…
@mentalnomad :stuck_out_tongue: do you think there is any truth to this?
@conor is the team aware of something like this? the idea that the team could potentially add these fruit phytonutrients from berries (or other fruits) to lower the glycemic load of Soylent if wanted/needed? (or potentially just suggest people to add fruits)

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Does fructose contained in a disaccharide have the same effects are free fructose? Does anyone know the safe limits of fructose intake from disaccharides?

Yes, fructose originating in a disaccharide is processed in the liver just like any other fructose.

Right. A disaccharide like sucrose (table sugar) is easily cleaved into a fructose and a glucose… and that fructose and glucose are chemically identical to any other fructose and glucose, and will be have all the same effects as any other fructose or glucose.

(Some disaccharides are less easily cleaved, and so it takes a long time before they base sugars are free… but those disaccharides aren’t relevant to this discussion.)

Yes - if you want to read the whole study he referenced, click here.

The fiber in whole berries slows down the sugar absorption, but also, the berries contain proanthocyanins and anthocyanins which inhibit the sugar uptake. The ugly side of this is to consider the role of proanthocyanins: it’s a plant defense which is toxic to insects. It also happens to screw with our digestion and inhibit our ability to take up sugar. Fortunately, it’s not nearly as bad for us as it is for insects, and slower sugar uptake is a good thing for modern diets.

However, he does get one important detail wrong… he talks about the body spiking the blood with fats in response to the hypoglycemic “starvation” effect after drinking the sugar-water… that’s pretty bogus. What’s really happening is that after you consume berries or sugar-water, the body stops putting fats into the bloodstream (because when sugar shows up in the blood, the fat is not necessary, so it stops - sugar is your body’s preferred fuel.) When the sugar runs out, the body starts putting fat back in the blood. Since the sugar runs out quickest after a sugar-water meal, the fat returns sooner - but it’s not some sort of fat-spike panic response, as he suggests. It’s just the body trying to return the fat levels to normal. In other words, returning the fat levels to where they were before you drank the sugar.

Here’s the relevant picture from the study, which he didn’t show:

So, as you see, the sugar drink (called “Reference”) does have a bump up in fat between the 60 and 120 minute (2 hour) marks, but it’s not some sort of crazy spike. It’s just working its way back up to normal after the sugar is used up at 60 minutes. And normal, by the way, is where it started at minute 0, when they started drinking. As soon as the sugars start hitting the blood, the fat starts dropping… and it doesn’t start to rise back to normal until all the sugar is gone.

For easy reference, here’s the corresponding blood sugar chart:

The fat would also rise in the next hour for the berry trials, because the fat is going to rise back to normal in all three cases. It just doesn’t start until the sugar is all used up - which, for the berries, doesn’t happen until about 120 minutes.

No, I don’t think Soylent wants to be caught putting a toxin that inhibits digestion into Soylent to slow down sugar uptake. People would point and scream.


Looking back to the OP - this was an interesting study, but you don’t mention the actually interesting parts.

This study wasn’t testing to see whether dietary fructose is good or bad in normal diets… it was specifically testing to see how DHA counters the negative effects of an unhealthy spike in fructose.

It isn’t even called a fructose study, by name; it’s: “Systems Nutrigenomics Reveals Brain Gene Networks Linking Metabolic and Brain Disorders.”

They gave the rats a healthy diet, PLUS they spiked their water with fructose, so that they were getting a an unhealthy level of excess sugar. (Equivalent to a 60 kg human eating a normal diet, but then adding on a 2L bottle of sweetened soda every day.)

The rats reacted as expected - those getting a lot of extra sugar in the form of fructose had blood glucose spikes well above the mice that didn’t get the extra sugar… moreover, since the excess was all in the form of fructose, they could look at how gene expression was affected by fructose, specifically.

But the really cool thing was that the addition of DHA prevented the negative effects of the fructose. (They got theirs from flax seed.oil and a DHA supplement.) They did fat-equalize the diets with and without extra DHA, but they did not carb-equalize the diets with and without the fructose - this was intentionally testing the effects of a sugar overload (specifically, a fructose overload).

They did a lot of interesting work analyzing the gene expression involved, using gene-knockout mice, but that’s not too relevant to the discussion in this thread.

Whole study, for those who want to read it:

Systems Nutrigenomics Reveals Brain Gene Networks Linking Metabolic and Brain Disorders