Artificial sweeteners may offer short-term weight loss, but at what cost?
According to the article, Trends in the consumption of low-calorie sweeteners, more than 30% of Americans report daily consumption of non-nutritive sweeteners such as aspartame, sucralose, and stevioside. As Americans’ weight continues to trend upward, more and more people are searching for alternatives to sugar to help shed unwanted pounds. In 2016, the CDC reported that more than one-third (36.5%) of American adults are obese. Linear time trends forecast that by 2030 over one-half of the United States population will be obese. The Academy of Nutrition and Dietetics have stated that non-nutritive sweeteners can help limit energy intake as one strategy to manage weight and blood glucose, however continual consumption has been paradoxically linked to weight gain and obesity. A previous meta-analysis reported conflicting findings; randomized controlled trials (RCTs) resulted in modest weight loss, whereas observational studies showed a significant association with an increase in BMI.
Researchers aimed to address the following objective: “Is routine consumption of non-nutritive sweeteners by adults and adolescents associated with adverse long-term cardiometabolic effects in RCTs and prospective cohort studies?” Researchers completed a systematic review and meta-analysis utilizing Embase, Cochrane Central Register and Medline databases. For RCTs, researchers required all participants to be enrolled in a study for 6 months or longer with the primary focus on long-term effects to reflect routine consumption of non-nutritive sweeteners. For observational studies, baseline intake of non-nutritive sweeteners along with baseline characteristics such as: weight, disease states, glucose metabolism and incidence of obesity were reported. From almost 12,000 citations researchers assessed 938 articles, 30 cohort studies and 7 RCTs involving a total of 406,910 individuals. The duration of the interventions averaged 6 months and most studies utilized food frequency questionnaires to evaluate consumption of non-nutritive sweeteners. The average follow-up was 10 years, range: 1-38 years. Two RCTs involving stevioside intake in hypertensive patients, and one RCT involving overweight participants consuming any artificially sweetened beverages displayed little change in BMI at 6 months [95% CI, median weight-loss 0.37kg]. Two cohort studies of non-nutritive sweetener use in healthy individuals demonstrated minor weight gain [95% CI, median weight-gain 0.6kg], similarly a third cohort study found that participants who consumed artificial sweeteners daily showed greater increase in BMI after 8 years than participants who did not.
There is little evidence in observational studies that non-nutritive sweetener use aids in maintainable weight loss. In 5 RCTs that evaluated the use of non-nutritive sweeteners in obese patients, there was no consistent change in weight [95% CI, median weight-loss 0.54 kg].
Secondary outcomes of the meta-analysis include cardiorenal outcomes and metabolic outcomes. Cardiorenal outcomes were not reported in any of the 7 RCTs, however among the cohort studies, researchers found that high non-nutritive sweetener intake was associated with an increased risk of developing hypertension over 5-38 years of follow-up. Additionally, high non-nutritive sweetener consumption was associated with an increased risk of obesity, diabetes, and cardiovascular events. Evidence from the RCTs evaluated does not overwhelmingly support the anticipated benefits of artificial sweeteners on weight management. However, the observational data suggests that regular intake of artificial sweeteners may increase a patient’s risk of experiencing a cardiovascular event, gaining weight, or developing diabetes. Patients consuming non-nutritive sweeteners regularly may believe they are making healthy choices and may compensate with extra food or treats because they are “saving calories” drinking diet drinks. Healthcare providers are split, with one-half arguing that ultimately the calorie deficit helps with weight loss while others argue that routine consumption may confuse and reprogram the metabolism resulting in weight gain, insulin resistance and glucose intolerance. The lack of research on the long-term effects of non-nutritive sweeteners is astounding and clearly more studies are needed to understand the effects non-nutritive sweeteners have on the body.
- Trials averaging 6 months– 1 year have shown that non-nutritive sweeteners may aid in initial weight loss but that most patients find this unsustainable.
- Non-nutritive sweeteners have been paradoxically linked to weight gain, obesity, development of diabetes and increased risk of cardiovascular events.
- Some patients may see the calories “saved” by drinking diet drinks as rationale to consume higher calorie food items resulting in weight gain.
Azad, Meghan B., et al. “Nonnutritive sweeteners and cardiometabolic health: a systematic review and meta-analysis of randomized controlled trials and prospective cohort studies.” Canadian Medical Association Journal 189.28 (2017): E929-E939.
Finkelstein, Eric A., et al. “Obesity and severe obesity forecasts through 2030.” American journal of preventive medicine 42.6 (2012): 563-570.
Wendling, Patrice. “Artificial Sweeteners Linked to Higher BMI, Cardiometabolic Risk.” Medscape Log In. N.p., 31 July 2017. Web. 10 Aug. 2017.
Jessica Lambert R.Ph., PharmD. Candidate, USF College of Pharmacy