Artificial sweeteners may be linked to risk of weight gain and a greater risk of obesity, high blood pressure, diabetes, and heart disease, found a Canadian systematic review.
Intake of artificial sweeteners is not consistently linked to a decrease in body weight, body mass index, or waist circumference, found the review of randomised control studies. However, a significant association was found between consumption of artificial sweeteners and increases in measures of body weight, BMI, and waist circumference, drawing from observational studies.
Obesity is a public health challenge that affects more than one third of adults in the US. Furthermore, obesity contributes to type 2 diabetes and cardiovascular disease, reports Medical News Today. Research showing that sugar consumption may fuel the obesity epidemic has triggered the upsurge in popularity of non-nutritive sweeteners (artificial sweeteners), such as aspartame, stevioside, and sucralose. In fact, in 2008, more than 30% of US adults consumed artificial sweeteners daily, and this proportion is on the rise.
The report says emerging evidence indicates that artificial sweeteners may have an adverse effect on metabolism, gut bacteria, and appetite. What is more, studies suggest that chronic exposure to artificial sweeteners may result in increased food consumption and weight gain.
According to the Academy of Nutrition and Dietetics, artificial sweeteners can be used as a strategy to manage weight or blood sugar by helping to limit energy intake. However, artificial sweetener consumption has been correlated with weight gain and obesity.
Dr Ryan Zarychanski and Dr Meghan Azad, assistant professors of the Rady faculty of health sciences at the University of Manitoba, and colleagues aimed to determine whether regular artificial sweetener consumption is associated with adverse long-term effects on weight and heart disease.
The team conducted a systematic review that included 37 studies that followed more than 400,000 individuals for around 10 years. In total, seven of the studies were randomized controlled trials, which are considered the gold standard in clinical research. The randomized controlled trials followed 1,003 people for around 6 months
The randomised controlled trials with a short follow-up period indicated that intake of artificial sweeteners is not consistently linked to a decrease in body weight, body mass index (BMI), or waist circumference.
In the longer observational studies, however, findings pointed toward a significant association between consumption of artificial sweeteners and increases in measures of body weight, BMI, and waist circumference.
Moreover, the researchers reported a link between artificial sweetener consumption and a higher risk of obesity, high blood pressure, type 2 diabetes, stroke, and heart disease. The authors note that there is no data available from randomised controlled trials to confirm these observations, however.
“Despite the fact that millions of individuals routinely consume artificial sweeteners, relatively few patients have been included in clinical trials of these products. We found that data from clinical trials do not clearly support the intended benefits of artificial sweeteners for weight management,” says Zarychanski
Lead author Azad follows on by saying, “Caution is warranted until the long-term health effects of artificial sweeteners are fully characterised.” Azad and her collaborators at the Children’s Hospital Research Institute of Manitoba are researching how consumption of artificial sweeteners by women in pregnancy may influence their infant’s weight, metabolism, and gut bacteria.
“Given the widespread and increasing 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,” Azad concludes.
Background: Nonnutritive sweeteners, such as aspartame, sucralose and stevioside, are widely consumed, yet their long-term health impact is uncertain. We synthesized evidence from prospective studies to determine whether routine consumption of non-nutritive sweeteners was associated with long-term adverse cardiometabolic effects.
Methods: We searched MEDLINE, Embase and Cochrane Library (inception to January 2016) for randomized controlled trials (RCTs) that evaluated interventions for nonnutritive sweeteners and prospective cohort studies that reported on consumption of non-nutritive sweeteners among adults and adolescents. The primary outcome was body mass index (BMI). Secondary outcomes included weight, obesity and other cardiometabolic end points.
Results: From 11 774 citations, we included 7 trials (1003 participants; median follow-up 6 mo) and 30 cohort studies (405 907 participants; median follow-up 10 yr). In the included RCTs, nonnutritive sweeteners had no significant effect on BMI (mean difference −0.37 kg/m2; 95% confidence interval [CI] −1.10 to 0.36; I2 9%; 242 participants). In the included cohort studies, consumption of nonnutritive sweeteners was associated with a modest increase in BMI (mean correlation 0.05, 95% CI 0.03 to 0.06; I2 0%; 21 256 participants). Data from RCTs showed no consistent effects of nonnutritive sweeteners on other measures of body composition and reported no further secondary outcomes. In the cohort studies, consumption of nonnutritive sweeteners was associated with increases in weight and waist circumference, and higher incidence of obesity, hypertension, metabolic syndrome, type 2 diabetes and cardiovascular events. Publication bias was indicated for studies with diabetes as an outcome.
Interpretation: Evidence from RCTs does not clearly support the intended benefits of nonnutritive sweeteners for weight management, and observational data suggest that routine intake of nonnutritive sweeteners may be associated with increased BMI and cardiometabolic risk. Further research is needed to fully characterize the long-term risks and benefits of nonnutritive sweeteners.
Meghan B Azad, Ahmed M Abou-Setta, Bhupendrasinh F Chauhan, Rasheda Rabbani, Justin Lys, Leslie Copstein, Amrinder Mann, Maya M Jeyaraman, Ashleigh E Reid, Michelle Fiander, Dylan S MacKay, Jon McGavock, Brandy Wicklow, Ryan Zarychanski