A team of researchers at the University of Manitoba have found that artificial sweeteners can lead to an increased body mass index and cardiovascular disease. The study analysed existing research pertaining to the health effects of sugar substitutes, such as aspartame and sucralose. The findings have, however, come as a surprise due to previous research on these sweeteners promoting the benefits of these substitutes.
In 2014, both the American Diabetes Association and the American Heart Association approved the benefits of artificial sweeteners in comparison to regular sugar. On their websites, it was stated that all of the artificial sweeteners, with the exception of aspartame, can be passed through our bodies with no extra calories.
“I think originally it was calories which were the problem, and we’ve made something that was zero calories, so we’re good,” Azad told The Washington Post. “But we’re learning that it’s not just about the calories.”
Azad and her team searched MEDLINE, Embase and Cochrane Library for randomized controlled trials (RCTs) that measured the effects of non-nutritive sweeteners as well as cohort studies that reported on the consumption of these sugar substitutes amongst adults and teenagers.
Data from the RCTs showed that non-nutritive sweeteners do not have a strong correlation with body mass index (BMI) or other measures of body composition. However, the cohort studies showed that the consumption of non-nutritive sweeteners was linked to a slight rise in BMI, as well as increases in weight and waist circumference, and higher incidence of obesity, hypertension, metabolic syndrome, type 2 diabetes and cardiovascular diseases.
Earlier this year, a new study in the Journal of the Academy of Nutrition and Dietetics reported that almost half of adults and a quarter of children in America consume artificial sweeteners every day. Most of these sugar substitutes are taken from diet soda, while others are from products such as yogurt and granola bars, Azad said.
“We need more evidence from better quality studies to know for sure the cause and effect, but there does seem to be at least a question about the daily consumption of these drinks,” she said.
Even though Azad stressed that the studies centred on individuals trying to lose weight or had other medical conditions, and therefore more thorough studies are required, Azad believes that a general conclusion can still be drawn about these non-nutritive sweeteners: that they are linked to long-term increases in body weight, body mass index and waist circumference.
A link between artificial sweeteners and weight gain does indeed appear to exist, Azad said, but she also stressed the importance of continues research to provide more insight. For now, however, Azad has recommended that the assumption should not be that food and drinks with artificial sweeteners are the best replacement for sugar.
William Cefalu, an officer from the American Diabetes Association, commented that artificial sweeteners are useful for decreasing carbohydrates and blood-glucose levels, but he agreed that more studies about the long-term effects were needed. Cefalu stated that these observational studies have their own limitations because of self-reporting. Instead, a randomized control trial measuring the precise intakes of artificial sweeteners and their impacts would be much more precise.
Si Wu is a Physics alumnus from Imperial College London
Banner image: diet drinks, Wichai