----- "Geoffrey Purcell" <[log in to unmask]> wrote: 
> *I missed this post a while back". 
> 
> Re Todd's comments:- I still don't see the problem.Even if fructose is a real problem(still unproven, overall), 

The effect of fructose on the liver, and the mechanism by which it causes problems, is now understood in minute detail. This is far more direct "proof" than any number of epidemiological studies. 

> then palaeolithic tribes and those following a modern version of the Palaeolithic diet should have no issues re fructose given that they didn't indulge in fruit-juices or vast amounts of raw fruits in their diet. After all, even palaeo-oriented hunter-gatherers are cited as not deriving more than 25% of their overall calories from plant-foods, even when around the equator. And , like I said, while there are a plethora of studies done on refined fructose such as corn-syrup, the number of studies damning natural fructose is minimal by comparison(so far I've only come across 1). 

This is reasonable, but it means that any proposal for a modern version of the Paleolithic diet needs to abandon the simplistic view that paleo=good and non-paleo=bad. The dosage matters. For example, if we take 25% of energy as a reasonable ceiling for plant food intake, that comes to about 100g, in a 2,000 calorie diet. We may still ask what percentage of *that* should be fructose? As you say, actual paleolithic people didn't consume vast amounts of fruit juice, or lots of whole fruits, and the fruits they ate weren't cultivated to express a maximum of fructose (which is considerably sweeter than glucose). But modern well-intentioned paleodieters might easily ingest vast amounts of fructose in these ways, especially if they believe it to be harmless. Despite our wish that the paleodiet concept should be simple, and without need to "count" anything, this is an area where people need to be vigilant. And, as I've stated before, we can't assume that people who already have metabolic syndrome when they come to the paleodiet will be able to tolerate even the 25 or so grams that may well be safe for those who don't have it. 

Todd Moody