Splenda may not be so splendid after all

25-Sep-2008 -
Consumption of the sweetener Splenda at doses within the US FDA’s Acceptable Daily Intake may suppress beneficial bacteria in the gut, and cause weight gain, says a new rat study.
According to findings published in the peer-reviewed Journal of Toxicology and Environmental Health, Part A, a 12-week feeding study with the sweetener also affected the expression of certain enzymes known to interfere with the absorption of nutrients and pharmaceuticals.

The study, performed by researchers from Duke University in North Carolina and co-sponsored by the Sugar Association, raises questions about the safety profile of the sweetener, reported to be used as an ingredient in over 4,000 products worldwide.
Professor Abou-Donia and his co-workers report that, at the end of the initial 12 weeks, significant reductions in the levels of so-called beneficial bacteria were observed. Specifically, the numbers of total anaerobes was decreased by 50 per cent, relative to the control animals, while bifidobacteria, lactobacilli, and Bacteroides were reduced by 37, 39, and 67.5 per cent respectively. (Good Good Ya-all! That's as bad as taking penicillin long term!)

The body weight of the animals in all the groups increased, but significant increases were observed in animals receiving Splenda, said the researchers. Control animals experienced an increase in body weight of 93 per cent over the 12 weeks. Body weight increases in the 100, 300, 500, and 1,000 mg of Splenda per kg per day groups were 104, 101, 102, and 88.5 per cent, respectively.

“The lack of a dose-response effect of Splenda on body weight is likely due to the combined elevation of both intestinal P-gp and CYP that affected the bioavailability of Splenda,” stated the researchers. “At the higher concentrations, less Splenda was absorbed due to the increase in the expression of both P-gp and CYP proteins.”

(They talk some scientific gabbly stuff, then...)

Low beneficial bacteria levels, and elevated P-gp and CYP levels were maintained after the 12 week recovery period, said the researchers. (So they ate Splenda for 12 weeks, then didn't eat it for 12 weeks and still hadn't recoved their healthy gut bacteria. I wonder if people to use Splenda get a lot of yeast infections?)

“Evidence indicates that a 12 week administration of Splenda exerted numerous adverse effects, including a reduction in beneficial faecal microflora, an increased faecal pH, and enhanced expression levels of P-gp, CYP3A4, and CYP2D1, which are known to limit the bioavailability of orally administered drugs,” concluded the researchers.