Myth of Fact? Weight Gain.

Myth: Low-calorie sweeteners, such as aspartame, cause weight gain.

FACT: Trial after trial consistently demonstrates that substituting aspartame and other low cal sweeteners for caloric sweeteners are associated with modest weight loss.


HUMAN CLINICAL TRIALS — Modest weight loss with substitution of diet products/beverages

Blackburn et al, AJCN, 1997 (http://ajcn.nutrition.org/content/65/2/409.long)
  • Landmark study (RCT), n=163 obese women (Harvard Med. School)
  • Randomly assigned to consume vs. abstain from aspartame
  • Research question:  Does the addition of aspartame to a multidisciplinary weight-control program improve weight loss and long-term control of body weight?
 Results Aspartame group lost significantly more weight overall and regained significantly less weight during maintenance [1-yr] and follow-up [2-yrs] than non-aspartame group.
Conclusion excerpt “These data suggest that participation in a multidisciplinary weight-control program that includes aspartame may facilitate the long-term maintenance of reduced body weight.”
Peters et al, Obesity, 2014 (http://onlinelibrary.wiley.com/doi/10.1002/oby.20737/epdf)
  • 12-week Prospective Study, (RCT); two sites (N=303) (Univ. CO, Temple Univ.)
  • Comparison of water vs. NNS beverages (including aspartame) on weight loss
  • Diet Beverage group ↓ 13 lbs
  • Water group ↓ 9 lbs
Conclusion excerpt “These results strongly suggest that NNS beverages can be part of an effective weight loss strategy and individuals who desire to consume them should not be discouraged from doing so because of concerns that they will undermine short-term weight loss efforts.”
 Tate et al. AJCN, 2012 (“CHOICE” RCT) (http://ajcn.nutrition.org/content/95/3/555.full)
  • 6 month, n= 318 (UNC/Chapel Hill)
  • Research question: Will substituting diet beverages or water for caloric beverages aid in weight loss comparable to a basic weight loss support program? (LCS not defined)
 Results Myth 1

  • Answer: “Yes”
  • Average weight losses:
    • Counseling (AC) group – lost ~1.75% bw
    • Water (WA) substitution group — lost ~2% bw
    • Diet beverage (DB) substitution – lost ~2.5% bw
  • Water or diet beverage group doubled their odds of achieving a 5% weight loss.
  • Preference for sweet foods/beverages did NOT increase.
Conclusion excerpt “This strategy could have public health significance and is a simple, straightforward message.”
 de Ruyter et al, NEJM, 2012 (http://www.nejm.org/doi/full/10.1056/NEJMoa1203034#t=article)
  • 18-month Double-Blind, Placebo Control, (RCT) (Univ. Amsterdam)
  • (n=641, normal weight children, 4.8 years – 11.9 years of age)
  • Replaced sugar-containing beverages w/ LCS beverages (including sucralose + Ace K)
 Results BMI, body weight, skin-fold thickness, waist-to-hip ratio, and fat mass increased significantly less in the sugar-free group.
Conclusion excerpt “Masked replacement of sugar-containing beverages with non-caloric beverages reduced weight gain and fat accumulation in normal-weight children.”
 Ebbeling et al, NEJM, 2012  (http://www.nejm.org/doi/full/10.1056/NEJMoa1203388#t=article)
  • One-year intervention (RCT) to assess the effect on weight gain by overweight and obese adolescents (Multi-center, Boston)
  • Substituted non-caloric beverages; reduce consumption of sugar-sw. beverages (LCS not specified).
  • Smaller increase in BMI and greater decrease body weight at 1 year intervention with substitution of water or diet beverage.
  • Effect was neutral at year 2 (1 year post intervention)
Conclusion excerpt “Replacement of sugar-sweetened beverages with non-caloric beverages did not improve body weight over a 2-year period, but group differences in dietary quality and body weight were observed at the end of the 1-year intervention period.”

LITERATURE REVIEWS – Body of human trials confirm potential benefit

 Zheng et al, JAND 2015 (http://www.andjrnl.org/article/S2212-2672(15)00112-4/abstract)
 Overview Systematic review of prospective cohort and RCT’s examining effects of substituting beverage alternatives for SSBs on long-term health outcomes in children and adults.
 Conclusion excerpt “The overall consensus of our review was that SSB substitution with beverage alternatives such as water and low-calorie beverages may have beneficial effects on long-term body weight management.”
 Academy of Nutrition and Dietetics EAL 2009; Reiterated JAND Position Paper 2012 (http://bit.ly/1L6SRXx
 Question In adults, does using foods or beverages with aspartame in an energy restricted or ad libitum diet affect energy balance (weight)?
Conclusion statement
(Grade 1)
 “Use of aspartame and aspartame-sweetened products as part of a comprehensive weight loss or maintenance program by individuals may be associated with greater weight loss and may assist individuals with weight maintenance over time.”
 Miller & Perez, AJCN, 2014  (http://ajcn.nutrition.org/content/early/2014/06/18/ajcn.113.082826.full.pdf+html)
 Overview Meta-analysis of 15 RCT and 9 prospective cohort studies examined the relation between low-calorie sweeteners (from foods, beverages, or table top sweeteners) and body weight and composition.
  • In RCTs, LCS modestly, but significantly reduced all outcomes examined, including body weight, BMI, fat mass and waist circumference.
  • Observational studies showed no association between LCS intake and body weight or fat mass and a small positive association with BMI.
Conclusion excerpt “Data from RCT’s, which provide the highest quality of evidence for examining the potentially causal effects of LCS intake, indicate that substituting LCS options for their regular-calorie versions results in a modest weight loss, and may be a useful dietary tool to improve compliance with weight loss or weight maintenance plans.”
 Mattes and Popkin, AJCN, 2009  (http://ajcn.nutrition.org/content/89/1/1.full.pdf+html)
 Overview Comprehensive review on appetite, food intake and related mechanisms. (224 research studies referenced)
  • Nonnutritive sweeteners were not found to heighten appetite when ingested in conjunction with other energy sources.
  • Addition of NNS to diets poses no benefit for weight loss/ reduced weight gain w/out energy restriction.
  • Mechanisms by which NNS are purported to promote energy intake and contribute to obesity are not supported by the available evidence.
Conclusion excerpt “. . . if nonnutritive sweeteners are used as substitutes for higher-energy-yielding sweeteners, they have the potential to aid in weight management.”
 De la Hunty et al, Brit Nutr J, 2006 (http://bit.ly/1qDGepO)
Overview Meta-analysis (16 studies) on the effect of aspartame on weight loss, weight maintenance and energy intakes in adults; addresses the question of energy compensation and whether the use of aspartame-sweetened foods and drinks is an effective way to lose weight.
 Results The meta-analysis demonstrates that using foods and drinks sweetened with aspartame instead of sucrose results in a significant reduction in both energy intakes and bodyweight.
Conclusion excerpt “This review has shown that using foods and drinks sweetened with aspartame instead of those sweetened with sucrose is an effective way to maintain and lose weight without reducing the palatability of the diet.”


 Mozaffarian et al, NEJM, 2011 (http://bit.ly/1OjsXAH)
  • Prospective investigations, 3 separate cohorts (n=120,877 women and men free of chronic disease and not obese at baseline): Nurses’ Health Study (1986-2006) and NHS 11 (1991-2003), Health Professionals Follow-up Study (1986-2006)
  • The relationships between lifestyle factors and weight change were evaluated at 4-year intervals
 Results Large scale epidemiological studies that controlled for reverse causality; showed neutral to beneficial effect of diet soda on body weight.

Myth 1.2

Conclusion excerpt “Our findings suggest that both individual and population-based strategies to help people consume fewer calories may be most effective when particular foods and beverages are targeted for decreased (or increased) consumption.”


National Weight Control Registry Catenacci et al, Obesity J, 2014 (http://onlinelibrary.wiley.com/doi/10.1002/oby.20834/abstract)
  • Cross-sectional study to evaluate prevalence of and strategies behind low/no calorie sweetened beverage consumption in successful weight loss maintainers.
  • Online survey administered to 434 members of the National Weight Control Registry individuals who had  lost > 13.6 kg (6 lbs) and maintained weight loss for > 1 year
Results Regular consumption of low/no calorie sweetened beverages is common in successful weight loss maintainers for various reasons including helping individuals to limit total energy intake.
Conclusion excerpt ”Changing beverage consumption patterns was felt to be very important for weight loss and maintenance by a substantial percentage of successful weight loss maintainers in the National Weight Control Registry.”


Presented at: Academy of Nutrition and Dietetics FNCE 2015

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