Another week, another
observational trial showing the evils of artificial sweeteners.
The press releases and general lay public information from this trial are awful. I know universities communication teams love controversial topics as they increase the hit count. But this is garbage.
Observational trials are insensitive to pick up these effects, but they create a nice easy story. You know, the "requires further investigation" type claims at the end of the paper. Sure. It also requires further investigation with examinations that are not just dataset milking piles of junk.
More to the point, this finding is nothing new. Its most likely due to the fact that people know they are fat, therefore consume diet beverages - then treat it as permissive - I've been good and now i get to eat whatever. Much like the gym goers who think because they did 20 minutes of cycling they deserve a triple fat mocha latte with a cookie. Or like the previous research on telling people the product is low fat resulted in increased consumption.
Now, last year in the American Journal of Clinical Nutrition, there was an interesting meta-analysis published looking into this. It was unique, in that it performed a meta-analysis on observational cohorts and also experimental trials.'
This paper can be found
here.
It found that observationally, artificial sweetener consumption was associated with no real differences other than a significantly higher BMI (or significantly associated with a slightly higher BMI - as the authors say).
The meta-analysis of the experimental trials showed decreased bodyweight, decreased BMI, decreased fat mass and decreased waist hip ratio.
Why the difference? Because observational trials are inadequate to decipher most of which they are asked to do. But also, data mining of observational data sets (cough, Willett
et al) will find enormous quantities of spurious associations that have nothing to do with anything. Nothing like performing 5000 statistical tests on the same dataset to throw up some pointless garbage.
Just because fat people drink diet beverages doesn't mean that diet beverages caused the fatness.
Also, quit hyping your latest and greatest observational claptrap just because you want to advertise your University or Department. Have some ethics.