Non-nutritive sweeteners (NNS) have been used to replace added sugars in foods/beverages. Research related to NNS consumption and metabolic syndrome (MetS) is of great importance as NNS are often used by individuals who are looking to improve their health. The objectives of this investigation were to determine whether an association between NNS consumption (total and individual types) and MetS exists, and if any of the five risk factors for MetS were more significantly impacted by NNS consumption. Four NNS were included in this study: saccharin, sucralose, aspartame, and acesulfame potassium. Adult participants (n = 125) from Southwest Virginia were recruited for a cross-sectional investigation. Demographics, three 24-hour dietary recalls, and values for MetS (blood pressure, waist circumference, and glucose, triglyceride, and HDL levels) were collected. Statistical analyses included descriptives and multiple linear regressions models. Of the 125 participants, 63 were classified as NNS consumers and 18 met the criteria for MetS. There was a significant positive relationship between MetS and total NNS consumption (p=0.007) and MetS and aspartame (p=0.012). When looking at individual MetS risk factors, waist circumference, triglyceride and glucose values were significantly positively associated with NNS consumption (p≤0.001) and aspartame, sucralose, and saccharin (all p≤0.027). Some limitations to current NNS research were addressed, such as, examining associations between individual NNS types and not using diet soda as a proxy for NNS consumption. More research is needed to address the bias of self-reported data and the lack of randomized controlled trials to inferentially test the impact of NNS consumption. / Master of Science

The overconsumption of added sugars leads to negative effects on health such as an increased risk for obesity, cardiovascular disease, and diabetes. With approximately 50% of added sugars in the American diet being attributed to sugar-sweetened beverage (SSB) intake, non-nutritive sweeteners (NNS) are recommended as potential replacements. The purpose of this secondary analysis of Talking Health, a 6-month SSB reduction intervention, was to explore 1) changes in NNS consumption patterns between SIPsmartER (n=101) and MoveMore (n=97) interventions, and 2) differences in demographics between three groups of various SSB-NNS consumption change patterns (Group 1: decreased SSB, increased NNS; Group 2: decreased SSB, no change in NNS; Group 3: increased SSB, regardless of NNS). Results showed that the SIPsmartER intervention significantly created more new NNS users than MoveMore after the 6 month intervention. There were significant between group over time differences for intake of aspartame, sucralose, and total NNS, with intake increasing for SIPsmartER participants as compared to MoveMore. However, when exploring demographics between the three SSB-NNS consumption change groups, no differences were found between those who successfully decreased SSB while increasing NNS and the other groups. While diet beverages were the most commonly consumed dietary source of NNS across groups over time, other sources such as tabletop sweeteners, yogurt, and meal replacement products contributed to total NNS intake. Future research is needed to identify those who would benefit most from using NNS as a tool to decrease SSB intake. This will help inform future interventions and provide appropriate strategies to decrease added sugars intake. / Master of Science / The overconsumption of added sugars leads to negative effects on health such as an increased risk for obesity, cardiovascular disease, and diabetes. With approximately 50% of added sugars in the American diet being attributed to sugar-sweetened beverage (SSB) intake, non-nutritive sweeteners (NNS) are recommended as potential replacements. The purpose of this secondary analysis of Talking Health, a 6-month SSB reduction intervention, was to explore 1) changes in NNS consumption patterns between SIPsmartER (n=101) and MoveMore (n=97) interventions, and 2) differences in demographics between three groups of various SSB-NNS consumption change patterns (Group 1: decreased SSB, increased NNS; Group 2: decreased SSB, no change in NNS; Group 3: increased SSB, regardless of NNS). Results showed that the SIPsmartER intervention significantly created more new NNS users than MoveMore after the 6 month intervention. There were significant between group over time differences for intake of aspartame, sucralose, and total NNS, with intake increasing for SIPsmartER participants as compared to MoveMore. However, when exploring demographics between the three SSB-NNS consumption change groups, no differences were found between those who successfully decreased SSB while increasing NNS and the other groups. While diet beverages were the most commonly consumed dietary source of NNS across groups over time, other sources such as tabletop sweeteners, yogurt, and meal replacement products contributed to total NNS intake. Future research is needed to identify those who would benefit most from using NNS as a tool to decrease SSB intake. This will help inform future interventions and provide appropriate strategies to decrease added sugars intake.

Controversy surrounds the use of artificial sweeteners (non-nutritive sweeteners [NNS]) as an effective weight-loss and/or maintenance strategy. This controversy is especially important as obesity is an epidemic in the United States. Excessive added sugar intake, primarily from sugar-sweetened beverages, has been linked to increased risk of overweight and obesity, as well as type 2 diabetes and cardiovascular disease. NNS provide minimal to no calories and thus, they have been suggested as a method to reduce added sugar intake, and consequently decrease energy intake, weight, and cardiometabolic risk. However, NNS intake has been associated with various health outcomes in observational studies and randomized controlled trials, including cancer, weight gain and loss, physiological and intestinal changes, cardiovascular disease, and diabetes. The uncertainties around the effect of NNS on health outcomes stem from a variety of limitations, one of which is inadequate dietary assessment methodology. Accuracy of dietary intake assessment methods is limited by the inability to distinguish between different types of NNS and lack of information about consumer use of NNS in a variety of beverages and foods. The purpose of this investigation is to explore NNS consumer characteristics and to characterize NNS intake in a sample of rural Southwest Virginian adults. This characterization is especially important for rural populations, as they are known to be high sugar-sweetened beverage consumers and are at an increased risk of obesity and chronic disease; thus, NNS could serve as a replacement method to facilitate cardiometabolic health. Cross-sectional data from a large randomized controlled trial, Talking Health (n=301), was utilized in this investigation to compare demographic characteristics, anthropometrics, biochemical markers, dietary quality, and dietary factors between NNS consumers and NNS non-consumers. This data was also used to characterize NNS intake (frequency, type, and source of sweetener). Of this rural sample, 33% consumed NNS, with sucralose being the most prevalent type of NNS and diet soda being the most frequently consumed source of NNS. NNS consumers had a higher BMI status than NNS non-consumers. However, NNS consumers had better overall dietary quality than NNS non-consumers. The characteristics of these NNS consumers and their intake patterns can be used to develop well-designed dietary intake assessment tools that accurately measure NNS intake, which can facilitate a better understanding of the associations of NNS with health outcomes. / Master of Science

Non-nutritive sweeteners (NNS) are frequently used as substitutes for added sugars. NNS are difficult to study due to the inability to accurately measure the amounts individuals consume, as well as limitations in study design and methods, including reliance on observational study designs, the use of diet soda as a proxy of total NNS intake, and the grouping of NNS into a single category rather than studying NNS as individual products. New dietary assessment methods and improved study design and methods are needed to advance researchers' abilities to study NNS and their impact on consumers' health. The objectives of this dissertation were to 1) determine validity and reproducibility of a novel NNS food frequency questionnaire (NNS-FFQ), 2) develop methodology for an objective NNS urinary biomarker, 3) identify an appropriate carrier for NNS intake in studies, and 4) examine the literature on the relationship between NNS and weight-related outcomes based on study design and methods. Objectives 1 and 2: participants (n=125) completed three 24-hr dietary recalls, the NNS-FFQ, and 2 24-hr urine samples. NNS intake via NNS-FFQ and recalls were compared using Bland-Altman analyses, with agreement levels ranging from 92.7-99.2% for individual NNS types and total intake. The NNS biomarker methodology was developed using ultra performance liquid chromatography (UPLC-MS/MS), which analyzes each sample for the presence of NNS and related metabolites. This method observed a range from very strong presence of NNS to not detectable, indicating that this biomarker could identify specific NNS consumption (n=9). Objective 3: a sensory evaluation (n=67) was conducted to identify if applesauce or water was a more appropriate carrier for NNS for future interventions. Applesauce was preferred (sucralose=83.6%; aspartame=79.1%; stevia=74.6%) significantly more than water (p≤0.001), indicating that applesauce could be used as an acceptable carrier of NNS in research studies. Objective 4: a systematic literature review focusing on study design and methods used in investigations on NNS and weight-related outcomes found that 81% of RCT had improved weight outcomes, while 76% of observational studies had higher weight outcomes. Improving NNS study design and methods will increase the quality of research conducted on NNS and related health outcomes. / Ph. D. / Artificial sweeteners [non-nutritive sweeteners (NNS)] are often used to replace added sugars. NNS are difficult to study due to the inability to accurately measure the amounts individuals consume, as well as limitations in study design and methods, including reliance on observational study designs, the use of diet soda to represent total NNS intake, and the grouping of NNS into a single category rather than studying NNS as individual products. New dietary assessment tools and improved study design and methods are needed to allow researchers better to study NNS and their impact on health. The objectives of this dissertation were to 1) to determine the ability of a NNS food frequency questionnaire (NNS-FFQ) to measure typical NNS intake, 2) develop methodology for an objective NNS urinary biomarker, 3) identify an appropriate carrier for NNS intake in studies, and 4) to review the currently available research on the relationship between NNS and weight status. Objectives 1 and 2: 125 participants completed three 24-hr dietary recalls, the NNS-FFQ to measure usual NNS intake, and 24-hour urine samples for a NNS biomarker. Amounts of NNS that consumers reported in recalls were compared to amounts reported in the NNS-FFQ, with the tools finding similar NNS amounts in participants’ diets. The NNS biomarker methodology was developed using ultra performance liquid chromatography (UPLC-MS/MS). This rapid method measures the presence of NNS and related products (saccharin, acesulfame potassium, sucralose, steviol glucuronide, and erythritol) in urine. Among 9 participants, this method identified wide differences, ranging from strong presence of NNS to not measureable. Objective 3: participants (n=67) completed a sensory evaluation (taste testing) study to identify a more appropriate food or beverage (applesauce or water) for NNS (sucralose, aspartame, and stevia) to be mixed with in research studies. Applesauce was preferred over water for all sweeteners (>74%), indicating that applesauce would be an acceptable NNS carrier. Objective 4: a systematic review on study design and research methods used in studies on NNS and weight-related outcomes. Improving NNS measurement tools and study design methods will improve the quality of research that can be conducted on NNS and related health outcomes.