Monday, February 27, 2012

Do Artificial Sweeteners Help with Weight Loss?

While it's always possible that real and conclusive dangers linked to the consumption of modern day artificial sweeteners will emerge, to date the data suggesting risk has been underwhelming to say the least, in great part due to the fact that the studies have been flawed in that they look at all comers' dietary consumption patterns and without very careful controls for diet, their conclusions are highly suspect. Reason being that there's a very real possibility that many people out there who drink artificially sweetened beverages do so as a means to assuage their guilty consciences in making less than stellar dietary choices - the "I'll have the super-sized combo with a Diet Coke please" phenomenon. Consequently it's certainly possible that artificial sweeteners are serving as a marker for chronic disease inducing diets rather than the chronic diseases' actual cause.

But that's a whole separate debate. Today I want to talk about the role of artificially sweetened beverages in a population that's actively trying to manage their weight, because after all, if there's any reason to encourage the consumption of artificial sweeteners, it has to be in the context of their use as overall calorie reducers, and unlike all comers, folks actively trying to lose weight are the ones I see on an every day basis in my practice.

This month's American Journal of Clinical Nutrition has just such a study where 318 folks with obesity who were drinking 280 or more calories daily from beverages were randomized to 6 months of either:

A) A control group that received monthly weigh ins, weekly monitoring and monthly group sessions on weight management.
B) A group where they received the same education but were encouraged to replace 200 or more of their liquid calories with water.
C) A group where they received the same education but were encouraged to replace 200 or more of their liquid calories with artificially sweetened beverages.

The results?

Somewhat to the chagrin of my own confirmation bias, they were rather underwhelming too. All groups lost roughly the same small amount of weight - including the control group who perhaps unsurprisingly, without explicitly being told to do so, also reduced their liquid calorie intake.

My take?

It was still the wrong population. These weren't the folks drinking 2L (808 calories) of Coca Cola a day, these folks were drinking on average 348 liquid calories a day, from all sources of liquid calories, not just sugar-sweetened ones. So yes, while it might have been soda pop, it could just have easily have been a few coffees with cream, half a glass of juice and a glass of wine a night, or for someone else, 2 fancy lattes. Yes, all targets worthy of reduction, but relatively tiny and potentially unfair targets - after all, it's improssible to replace milk, coffee cream, juice or alcohol with Splenda. Moreover, given the study folks aren't drinking enormous numbers of calories to begin with, reductions will likely be rather small, and indeed, at the end of the intervention the treatment groups were down about 200 liquid calories a day whereas the control group was down 100.

So perhaps it's not actually surprising to see an underwhelming result and I do wonder,would it really have been that difficult to specifically select a group already drinking a large amount of sugar-sweetened beverages with obviously available artificially sweetened alternatives?

So do I recommend artificially sweetened beverages?

Yes and no.

In an ideal world we'd drink far fewer sweet beverages. Whether they're sweetened by means of sugar or by means of artificial sweeteners, having palates craving cloyingly sweet isn't going to help in navigating through lower calorie choices or healthy fare.  For many, liquid calories, are the low hanging fruit of weight management - easy to reduce and consequently, I think it's certainly worth your own personal exploration of liquid calories, and if indeed you're drinking huge amounts of them, especially sugar sweetened ones, as a step-down strategy if you think you can use artificially sweetened beverages as you reduce the sweet drinks overall, I say go for it.

As far as I'm concerned, everyone's end goal is simply the smallest number of liquid calories they need to be satisfied, and ideally, the smallest amount of "sweet" beverages regardless of how the beverages got their "sweet" in the first place.

Tate, D., Turner-McGrievy, G., Lyons, E., Stevens, J., Erickson, K., Polzien, K., Diamond, M., Wang, X., & Popkin, B. (2012). Replacing caloric beverages with water or diet beverages for weight loss in adults: main results of the Choose Healthy Options Consciously Everyday (CHOICE) randomized clinical trial American Journal of Clinical Nutrition, 95 (3), 555-563 DOI: 10.3945/ajcn.111.026278