What the Iranians can teach us about fructose

Aaah the old 'sorry I've not blogged for ages' blog post. I've been on limited internet for a while due to the whole packing-moving-unpacking thing. And to be honest, I've also felt like I don't have anything new to share. Maybe writing about going sugar-free isn't blog worthy. I mean, it seemed like such a big step, a topic which would keep me writing for ages. But turns out that, once past the initial withdrawal and so on, and after trying a few recipes and finding that glucose is nearly as easy to work with as sucrose, it's not such a big deal. It's actually really easy. I've lost nearly 8kg so far, and it keeps going slowly down.

But then again, I do love to write, and so I find myself back here. I was inspired tonight by a study which David Gillespie posted to the Sweet Poison Facebook group. The original study is here. In a nutshell this study showed that high levels of fructose in the diet of men and women in Tehran, Iran was associated with an increased risk of metabolic syndrome, including higher body mass index and abdominal obesity.

Yeah, so? you might be saying. Isn't that the point of this blog, that fructose is bad, bad, bad, and that there is research to prove it? Well, yes, of course. But remember that most of the previous published research in this field has been in rats. And it's easy to dismiss this- a rat is (by definition) not a human. And while there have been other studies on people which showed that the rats were on the right track, they were limited, and open to criticism, for example that they fed people an unrealistic amount of fructose. A 2010 review of research published in the same journal as the new one concluded that "No fully relevant data account for a direct link between moderate dietary fructose intake and health risk markers".

So what we have now is one of the first human (ie, non rat) studies to show strong links between dietary fructose (the fructose that actual humans actually ate as part of their actual normal everyday diet) and metabolic syndrome, independent of age, physical activity, energy intake, dietary intake of other nutrients (eg fat) and BMI (all of which the researchers controlled for in their analysis).

The levels of fructose that this study suggest leads to problems seem quite high: >50g per day. At first glance it may seem like most of us are ok- surely I don't eat more than 50g fructose (100g sucrose), you might say. That's a heck of a lot of sugar. Visualise 22 teaspoons if you can, because that's how much it is. But consider that the average intake of fructose in this study was around 50g. So around half those studied (normal, everyday people) were eating over 50g per day. In their usual diet. And in case you think this only applies to Tehranian Iranians, US figures suggest that on average, Americans eat 55g of fructose per day- again, meaning that around half eat more than this. The data for Aussies is sketchy. In 1995 an Australian Bureau of Statistics survey showed that 20% of Australian energy intake came from sugar (in processed foods, fruit and veg, honey and other sweeteners). 20% of energy intake for a male aged 31-50 is between 104g and 185g per day (in fructose terms, 52-92.5g per day). More current figures are sparse to nonexistent because the ABS no longer conducts this particular survey, but a study being conducted with staff at the Epworth hospital (the SWEET study) may provide more answers (if and when it is published- will be looking out for that one). Preliminary data collected from participants showed that they ate 17 teaspoons per day in added sugars alone. Add in your fruit and veg (these are counted in the fructose total, even if they are healthy!) and I'll bet we are close to averaging the magic (in a bad way) 22 teaspoons.

I can't help but feel that this new study means that David Gillespie and others sounding the warning on fructose like Dr Robert Lustig should take some time out this week to give themselves a little pat on the back and maybe just send a little 'told you so' email to the nay-sayers who have insisted that fructose is fine and dandy like sugar candy. Like the university professors interviewed for this article reassuring the public that sugar is no threat, and that the National Health and Medical Research Council draft nutrition guidelines are being ridiculous for daring to suggest that Australians limit added sugars.

The bottom line is that we (most of us) eat a LOT of sugar. And we can now be more confident that this sugar may be doing us, the humans, and not just the rats, a lot of harm.