Despite being used as substitutes for sugar, a team of researchers from the School of Health at the University of Manitoba (Canada) has reviewed more than 11,000 scientific studies , discovering that, for overweight people, with hypertension or diabetes, the benefits of consuming zero calorie “non-nutritive sweeteners” are modest or nil. For other people, consuming these sweeteners can lead to heart disease and a host of other health problems such as type 2 diabetes, hypertension, or weight gain. The work has been published in CMAJ ( Canadian Medical Association Journal).
The consumption of artificial sweeteners is widespread and growing . Until now, the evidence about its negative effect on metabolism, appetite, or gut bacteria was mixed, so researchers at the George & Fay Yee Center for Healthcare Innovation at the University of Manitoba decided to conduct a systematic review of 37 studies (out of a total of 11,774) with more than 400,000 participants with a follow-up of at least one year. Only 7 of these studies were randomized controlled trials.
In the experiments, half of the participants were asked to consume alternative sweeteners such as aspartame and the other half were asked not to, with the intention of looking for differences between the two groups.
The trials did not show a consistent effect of artificial sweeteners on weight loss, and longer observational studies showed a link between artificial sweetener consumption and a relatively higher risk of weight gain and obesity, hypertension, diabetes, heart disease, and other health problems. That is, the non-nutritive sweeteners did not substantially help the study participants and, in many cases, caused a health problem.
“Despite the fact that millions of people regularly consume artificial sweeteners, relatively few patients have been included in clinical trials of these products,” says Ryan Zarychanski, co-author of the work. “We found that data from clinical trials do not clearly support the expected benefits of artificial sweeteners for weight management.”
“Caution is warranted until the long-term health effects of artificial sweeteners are fully characterized,” says study leader Meghan Azad.
In fact, his team has decided to launch a new study to understand how the consumption of artificial sweeteners by pregnant women can influence the weight gain, metabolism and intestinal bacteria of babies.
“Given the widespread and growing use of artificial sweeteners and the current epidemic of obesity and related diseases, more research is needed to determine the long-term risks and benefits of these products, as we need to learn how they work and how they affect different populations, if they do, “Azad said.
Reactions
The International Sweeteners Association, in response to this research states that ‘the conclusions of a new systematic review that low-calorie or no-calorie sweeteners could be associated with the risk of weight gain and heart disease based on the results of observational cohort studies, are not supported by the collective scientific evidence from well-designed human intervention studies and previous comprehensive systematic reviews and meta-analyzes . Importantly, these claims have not been confirmed by the results of the meta-analysis of randomized controlled trials conducted by the authors of this article. ‘
Therefore, ‘the design of a randomized controlled trial is necessary to attribute the observation of higher obesity rates in frequent consumers of low-calorie or no-calorie sweeteners in relation to the consumption of low-calorie or no-calorie sweeteners per se, rather than to other unquantified bias factors, with the intention of proving causality. This is the only study design relative to human studies that raises the level of demonstrating cause and effect, and in the case of the effect on body weight of low-calorie or no-calorie sweeteners, the evidence from randomized controlled trials is clear. and consistent, pointing to a modest benefit from the use of low-calorie or no-calorie sweeteners in the loss and maintenance of body weight, ‘concludes the IEA.
Referencia: Nonnutritive sweeteners and cardiometabolic health: a systematic review and meta-analysis of randomized controlled trials and prospective cohort studies. Canadian Medical Association Journal (2017). doi/10.1503/cmaj.161390
