Myth or Fact: Metabolic Syndrome.

MYTH: Low-calorie sweeteners, such as aspartame, promote Metabolic Syndrome, glucose intolerance, and increased risk of diabetes.

FACT: Aspartame has no effect on blood sugar levels; it has been declared safe for people with diabetes.

Human Clinical Trials
	Maersk et al, AJCN, 2012 (http://ajcn.nutrition.org/content/95/2/283.full.pdf+html)
Overview	6-month intervention, (RCT), n=47 overweight subjects (Multi-center, Denmark) Assigned to 4 different test drinks: regular soda, isocaloric semi-skim milk, aspartame–sweetened diet cola, and water Objective to compare the effects of sugar-sweetened soft drinks (SSSD) with those of isocaloric milk and noncaloric soft drink on changes in total fat mass and ectopic fat deposition (in liver and muscle tissue).
Results	Daily intake of SSDs for 6 months increased ectopic fat accumulation and lipids compared with milk, diet cola, and water. The effect of diet cola is mainly neutral and very similar to that of water
Conclusion excerpt	“The suggestions from observational studies that intake of diet cola can result in obesity, type 2 diabetes, and the metabolic syndrome are not supported by the findings of our current intervention, i.e., that the effect of diet cola on fatness, ectopic fat, and metabolic factors is mainly neutral and very similar to that of water. Also, diet cola was found to have effects nearly similar to milk in reducing blood pressure.”
	Bryant et al, Eur J Clin Nutr, 2014 (http://www.citeulike.org/article/13097452)
Overview	Randomized study design, n=10, healthy, normal weight individuals, mean age 21, studied on 4 separate days (Multi-center, UK and New York) To determine the effect of a panel of non-nutritive sweeteners: aspartame, saccharin, and acesulfame-K, delivered in doses that would be consumed in normal usage Given in combination with glucose, assessing effect on glycemic responses and appetite
Results	No additional effect of aspartame or saccharin on the blood glucose response to oral glucose at any time point Ace-K exerted a small effect None had an effect on perceptions of huger or fullness
Conclusion excerpt	“We conclude that there is no consistent evidence that non-nutrient sweeteners, when acutely consumed with glucose in dietetically relevant doses, have a class effect in modulating blood glucose in healthy human subjects. However, acesulfame-K may require further exploration.”
	Abdallah et al, AJCN, 1997 (http://ajcn.nutrition.org/content/65/3/737.full.pdf)
Overview	Double-blind placebo randomized trial, n=12 normal weight men (France) Investigated the effect of oral sensation of sweetness on cephalic-phase insulin release (CPIR) and other indexes associated with glucose metabolism using nutritive and nonnutritive sweetened tablets (aspartame/polydextrose) as stimuli.
Results	No change in plasma glucose, insulin or glucagon after aspartame consumption.
Conclusion excerpt	“This study suggested that oral stimulation provided by sweet non-flavored tablets is not sufficient for inducing CPIR.”
LITERATURE REVIEWS
	Gibson et al, Nutrition Bulletin, 2014 (http://onlinelibrary.wiley.com/doi/10.1111/nbu.12116/pdf)
Overview	Consensus statement on benefits of low-calorie sweeteners, International Sweetener Association Conference 2014
Conclusion excerpt	“LCS may have a beneficial effect on post-prandial glucose and insulin in healthy individuals and in people with diabetes.”
	Magnuson et al, Crit Rev Tox, 2007 (http://bit.ly/1XUbz9X)
Overview	Convene an independent international panel of experts* to review all scientific studies and assess the safety of current consumption of aspartame. Panel spent 11 months reviewing > 500 scientific articles and reports on aspartame from past 30 years *Experts: Food toxicology, metabolism, carcinogenesis, pathology, neurotoxicology, epidemiology, toxicology of methanol & formaldehyde
Conclusion excerpt	“The weight of existing evidence is that aspartame is safe at current levels of consumption as a nonnutritive sweetener.” . . .“Aspartame does not affect glycemic response in normal or diabetic individuals, and does not affect metabolic control or insulin release.”
	Pereira, Nutrition Reviews, 2013 (http://bit.ly/1O66FDm)
Overview	To provide a synthesis of the literature on the effects of non-nutritive or artificial sweeteners (ASBs) on body weight, cardiovascular disease, and type 2 diabetes. (review of 34 studies)
Results	Prospective observational studies have revealed mixed results, and it appears that reverse causality is a particular problem, since individuals who are at higher risk for weight gain may choose to consume ASBs in an attempt to control their weight or reduce disease risk. For experimental studies, the evidence currently suggests that obesity risk may be lower when low calorie sweetened beverages replace sugar-sweetened beverages (SSB) in the diet. It appears that the association between low calorie sweetened beverage intake and type 2 diabetes is likely an artifact of reverse causality.
Conclusion excerpt	“In terms of general public health recommendations or clinical advice, the scientific evidence does not presently support a blanket recommendation to either consume or avoid <low calorie sweetener> consumption in and of itself. However, for individuals who are frequent (several times per week or more) consumers of SSB and are overweight or at risk for weight gain and obesity, it seems reasonable, based on the evidence, to recommend replacing SSBs with either <low calorie sweetened beverages>, water, or other unsweetened low-calorie beverages, such as plain tea or coffee.”
	Renwick & Molinary, Br J Nutr, 2010 (http://bit.ly/1F2yNEo)
Overview	To explore the interactions between sweeteners and enteroendocrine cells and consequences for glucose absorption and insulin release. (33 studies reviewed)
Conclusion excerpt	“Data from numerous publications on the effects of low-energy sweeteners on appetite, insulin and glucose levels, food intake and body weight have shown that there is no consistent evidence that low energy sweeteners increase appetite or subsequent food intake, cause insulin release or affect blood pressure in normal subjects. The data from extensive in vivo studies in human subjects show that low-energy sweeteners do not have any of the adverse effects predicted by in vitro, in situ or knockout studies in animals.”

Presented at: Academy of Nutrition and Dietetics FNCE 2015

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