|Could diet coke really be more obeso- genic than regular coke? There is no evidence to prove that and still the mainstream interpretation of the latest rodent study in Nature says just that.|
Before I go on with my criticism of a recently published study in Nature (Suez. 2014), I would suggest we'll first take a look at study design and outcome, to make sure not just Steven and Conor, both of whom asked my opinion on the study on Facebook, know what we are talking about.
Suez et al. claim that their study, a 10-week study in the course of which germ-free mice (no bacteria in the gut at the onset of the study) were fed standard chow and supplied with unlimited access to
- saccharin (artificially), sucralose or aspartame sweetened drinking water,
- naturally sweetened drinking water with either sucrose or glucose as a sweetener, or
- plain water as a control,
"[...t]hese NAS-mediated deleterious metabolic effects are abrogated by antibiotic treatment, and are fully transferrable to germ-free mice upon faecal transplantation of microbiota configurations from NAS-consuming mice, or of microbiota anaerobically incubated in the presence of NAS," (Suez. 2014)but they don't tell the reader without full-text access that the negative effects occurred only in four of the animals, were saccharin- and sccralose exclusive and did not occur with the often (falsely) derided sweetener aspartame (see Figure 1, right hand side).
|Figure 1: Changes in the bacterial make-up (left) and consequences for the glycemic response after 11 weeks on regularly or artificially sweetened drinking water and antibacterial treatment (Suez. 2014).|
You, as a SuppVersity reader know that this is not the first study to show significant effects of alternative sweeteners on the gut microbiome of the host.
|Previous experimental evidence shows that NAS promote, not hinder weight loss | learn more|
Accordingly, the results Suez et al. present in their latest paper would hardly be considered significant evidence of the existence of a similar problem in human beings, if there weren't the results of an on-going study the scientists are doing. A study that clearly indicates that "similar NAS-induced dysbiosis and glucose intolerance in healthy human subjects." (Suez. 2014)
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- Chen, Liwei, et al. "Reduction in consumption of sugar-sweetened beverages is associated with weight loss: the PREMIER trial." The American journal of clinical nutrition 89.5 (2009): 1299-1306.
- Daly, Kristian, et al. "Dietary supplementation with lactose or artificial sweetener enhances swine gut Lactobacillus population abundance." British Journal of Nutrition 111.S1 (2014): S30-S35.
- de Ruyter, Janne C., et al. "A trial of sugar-free or sugar-sweetened beverages and body weight in children." New England Journal of Medicine 367.15 (2012): 1397-1406.
- Goyal, S. K., and R. K. Goyal. "Stevia (Stevia rebaudiana) a bio-sweetener: a review." (2010).
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- Sørensen, Lone B., et al. "Sucrose compared with artificial sweeteners: a clinical intervention study of effects on energy intake, appetite, and energy expenditure after 10 wk of supplementation in overweight subjects." The American journal of clinical nutrition (2014): ajcn-081554.
- Subudhi, E., et al. "In vitro antimicrobial study of plant essential oils and extracts." Int. J. Microbiol 8.1 (2010): 1-6.
- Suez et al. "Artificial sweeteners induce glucose intolerance by altering the gut microbiota." Nature (2014). Ahead of Print.