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Childhood (ages 2-9 years) and adolescence (ages 10-19 years) make up important periods of human life. Food preferences and dietary behaviors are developing during this time, and health status can impact noncommunicable disease (NCD) risk in adulthood. Many of the behaviors associated with developing NCD are modifiable and include dietary behaviors. Globally, children and adolescents are impacted by NCD, and obesity prevalence is growing among this population. One of the recommendations for combating obesity is to promote the consumption of healthy foods and beverages and the reduction of sugar-sweetened beverage intake. In order to assess beverage patterns, the Healthy Beverage Index (HBI) was created for adults. This tool provides a score from 0-100, with higher scores indicating better adherence to evidence-based beverage recommendations. Because many beverage recommendations for children and adolescents differ from those for adults, the purpose of this thesis was to develop the HBI for U.S. Children and Adolescents (HBI-CA). National Health and Nutrition Examination Survey (NHANES) data was used to calculate HBI-CA scores among a sample of U.S. children and adolescents. The HBI-CA resulted in scores similar to the adult HBI and provides a reference of beverage pattern quality in this population. Significant differences in scores were found among males and females and certain races. Evaluation of the HBI-CA demonstrated its construct validity and reliability. The HBI-CA still needs to undergo predictive validity tests. Overall, the HBI-CA provides a method to assess beverage pattern quality in clinical, public health, and research settings for this important population. / Master of Science / Children (ages 2-9 years) and adolescents (ages 10-19 years) makeup an important population for the implementation of dietary interventions because they are still developing their food preferences and dietary behaviors. The rise of obesity among these age groups indicates that their dietary behaviors may not be aligned with recommendations. Beverages can easily be overlooked as a dietary component, but they currently constitute a large portion of daily energy intake. In order to assess beverage pattern quality in this population, the Healthy Beverage Index for U.S. Children and Adolescents (HBI-CA) was developed based on the HBI for adults. This tool provides a score from 0-100, with higher scores indicating better adherence to evidence-based beverage recommendations. The HBI-CA also provides a resource of comprehensive beverage recommendations for these age groups, which was previously limited in the literature. National Health and Nutrition Examination Survey (NHANES) data was used to calculate HBICA scores among a sample of U.S. children and adolescents. The HBI-CA resulted in scores similar to the adult HBI and provides a reference of beverage pattern quality in this population. Significant differences in scores were found among males and females and certain races. Evaluation of the HBI-CA demonstrated its ability to reliably and consistently measure beverage pattern quality. Future evaluation of the HBI-CA should include examination of the relationship between HBI-CA scores and dietary-related health outcomes. Overall, the HBI-CA provides a method to assess beverage pattern quality in clinical, public health, and research settings for this important population.

To properly evaluate initiatives targeting children's fruit and vegetable (FV) consumption, we need feasible and valid dietary assessment methods that are time, cost, and resource effective. The objectives of this study were to test the feasibility and validity of two methods, digital imaging (DI) and aggregate plate waste (APW), for assessing children's FV consumption. UVM dietary assessment team graduate students prepared and distributed FV snacks in two pre-school classrooms over 30 consecutive school days. Feasibility of APW was tested by recording the frequency and weight of waste sorting errors by pre-school children and performing paired t-tests comparing uncorrected and corrected FV waste. Feasibility was tested for DI by determining the total number of individual FV snacks from which FV consumption could be estimated using the digital images. Validity was tested for DI using paired t-tests to compare FV consumption as assessed by DI against actual consumption as assessed by weighed plate waste (WPW). A total of 159 cluster APW weights were recorded during the 20 days of APW collection, with an overall mean difference of 0.57 grams (p=0.440) between uncorrected and corrected FV waste. Researchers were able to capture 100-percent usable digital images, effectively displaying 214 individual FV snack servings over the 10-day DI study period. Percent agreement between the two digital image coders was 99.1-percent. DI estimations for individual FV item and cumulative consumption were strongly correlated with WPW (all above r=0.97). Overall FV consumption as estimated by DI differed from WPW by less than one gram, and DI estimations for individual FV items differed from WPW by no more than two grams. Paired t-tests revealed no significant difference between DI estimations of clementine (p=0.954) and peapod (p=0.806) consumption and WPW measurements. However, paired t-tests indicated statistically significant differences between DI and WPW measurements for overall (p=0.001), grape (p=0.031), carrot (p=0.008), and pepper (p=0.027) consumption. Both methods were feasible for assessing mean FV consumption. DI estimations for individual FV items and cumulative consumption were strongly correlated with WPW, suggesting that despite statistical significance between DI and WPW measurements in some cases, the DI method is still precise for mean FV consumption evaluation. APW may be especially advantageous for rapid and efficient evaluation of behavior change in response to interventions targeting children's FV consumption. Due to ease of administration and instantaneous results, the APW method reduces the need for trained research staff to be present, drastically increasing accessibility to group-level dietary assessment.

In primary care (PC) health providers are delivering nutrition advice and counselling to patients. Yet, a number of challenges have been identified in conducting dietary assessment (DA). Electronic DA (e-DA) tools within mobile apps or websites can potentially facilitate DA in team-based PC. The objective of the study was to explore current DA practices and use of e-DA tools by various disciplines of health providers in Family Health Teams (FHTs) using a mixed-methods sequential design. Data collection included interdisciplinary focus groups (FGs) and a web-based survey. Fifty health providers from various disciplines participated in 11 FGs. Identified themes included: 1) Assessment of diet in an interdisciplinary fashion; 2) Improvement of patients’ eating habits with use of e-DA tools; 3) Support of health providers with use of e-DA tools; and, 4) Integration of e-DA tools into FHTs. One hundred and ninety-one health providers from 89 FHTs were included in the web-based survey. The two studies found that most providers offer a DA very frequently with diverse DA methods. The use of e-DA tools by health providers and patients is still low, although registered dietitians significantly use more e-DA tools than other health providers. There was high interest among all disciplines in the use of e-DA tools for the management of obesity, diabetes and heart disease, especially for patient self-monitoring. Several recommendations were suggested to facilitate uptake of e-DA tools into practice. / Ministry of Health and Long-Term Care (MOHLTC). Primary Health Care Transition Fund.

Food fortification and nutrient supplementation are important strategies to address micronutrient deficiencies. Mandatory folic acid fortification was implemented in Canada and the U.S. in 1998 to reduce the incidence of neural tube defects (NTD). However, the actual amount of folic acid added to foods has not been reported in Canada. We analyzed 95 fortified foods and found that there is 50% more folate in foods than that reported in food composition tables, which are primarily based on minimum mandated fortification levels. We then determined if these observed folate overages impacted the prevalence of dietary folate inadequacy or intakes above the Tolerable Upper Intake Level (UL). Using data from the 2004 nationally-representative Canadian Community Health Survey (CCHS) 2.2 (n = 35,107), adjusted for folate overages, we found a low prevalence of folate inadequacy in Canada post-fortification. However, few women 14-50y consumed 400µg/d of synthetic folic acid, an amount associated with maximal protection against an NTD. Conversely, we also showed that use of folic acid-containing supplements led to intakes >UL in the general population. To develop a tool that would help clinicians identify women with red blood cell (RBC) folate concentrations that were not maximally protective against an NTD (<906nmol/L), we used data from the nationally-representative U.S. National Health and Nutrition Examination Survey 2003-2006 to define risk factors of RBC folate <906nmol/L. We found that 35% of American women 19-45y had RBC folate <906nmol/L. Younger age, low dietary folate intake, not consuming supplemental folic acid, smoking, and being African-American were associated with increased risk of RBC folate <906nmol/L. Given our observations of a low prevalence of folate inadequacy and folic acid supplement use leading to intakes >UL, we used CCHS 2.2 data to compare the diets of supplement users and non-users in terms of inadequacy and intakes >UL for other nutrients. We showed that the prevalence of inadequacy was low for most nutrients, and from diet alone, supplement users were not at increased risk of inadequacy compared to non-users. Furthermore, inclusion of supplements led to intakes >UL above 10% for vitamins A, C, niacin, folic acid, and iron, zinc and magnesium.

Food fortification and nutrient supplementation are important strategies to address micronutrient deficiencies. Mandatory folic acid fortification was implemented in Canada and the U.S. in 1998 to reduce the incidence of neural tube defects (NTD). However, the actual amount of folic acid added to foods has not been reported in Canada. We analyzed 95 fortified foods and found that there is 50% more folate in foods than that reported in food composition tables, which are primarily based on minimum mandated fortification levels. We then determined if these observed folate overages impacted the prevalence of dietary folate inadequacy or intakes above the Tolerable Upper Intake Level (UL). Using data from the 2004 nationally-representative Canadian Community Health Survey (CCHS) 2.2 (n = 35,107), adjusted for folate overages, we found a low prevalence of folate inadequacy in Canada post-fortification. However, few women 14-50y consumed 400µg/d of synthetic folic acid, an amount associated with maximal protection against an NTD. Conversely, we also showed that use of folic acid-containing supplements led to intakes >UL in the general population. To develop a tool that would help clinicians identify women with red blood cell (RBC) folate concentrations that were not maximally protective against an NTD (<906nmol/L), we used data from the nationally-representative U.S. National Health and Nutrition Examination Survey 2003-2006 to define risk factors of RBC folate <906nmol/L. We found that 35% of American women 19-45y had RBC folate <906nmol/L. Younger age, low dietary folate intake, not consuming supplemental folic acid, smoking, and being African-American were associated with increased risk of RBC folate <906nmol/L. Given our observations of a low prevalence of folate inadequacy and folic acid supplement use leading to intakes >UL, we used CCHS 2.2 data to compare the diets of supplement users and non-users in terms of inadequacy and intakes >UL for other nutrients. We showed that the prevalence of inadequacy was low for most nutrients, and from diet alone, supplement users were not at increased risk of inadequacy compared to non-users. Furthermore, inclusion of supplements led to intakes >UL above 10% for vitamins A, C, niacin, folic acid, and iron, zinc and magnesium.

Adolescence proves to be one of the most vulnerable development stages in the life of humans and therefore dietary assessment of this group is important, but complex. This is due to rapid growth during puberty and the development of new eating patterns that influence dietary intake. Adequate dietary intake in this age group is crucial, since adverse effects such as iron deficiency anemia, inadequate growth and dental caries can occur. Furthermore, dietary imbalance is a significant risk factor that can lay the groundwork for developing preventable complications in late adolescence and adult life such as non-communicable chronic diseases including obesity and diabetes mellitus type II and certain cancers, all leading causes of morbidity and mortality. Given the vulnerability of adolescents in terms of dietary intake, understanding their dietary intake is crucial. Dietary assessment of adolescents is influenced by social, physiological and psychological changes making accurate measurement of this group difficult. Hence, it is of fundamental importance to find a golden standard in terms of a dietary assessment method to use in this group. Several international studies investigated validity and reproducibility of the dietary intake of adolescents, measured with different dietary assessment methods. However, in South Africa only three validity and reproducibility studies have been published and none of them focused exclusively on adolescents. Since the validity of the results of dietary assessment methods of international studies cannot be extrapolated to South African black adolescents, this study emanated from the need to investigate whether multiple 24-hour recalls are valid and reproducible when used to assess the dietary intakes of black adolescents in a convenience sample of grade eight learners from a high school in a township in the North West Province. The study was nested in the multidisciplinary "Physical, Activity in the Young" (PLAY) study. Firstly, the optimal number of 24-hour recalls was determined by calculation of reproducibility coefficients for energy, selected nutrients and food groups. Results showed that four repeated 24-hour recalls provided the optimal reproducibility for black peri-urban South African adolescents. Secondly, the search for a reference method to compare energy intake against energy expenditure led to an investigation into basal metabolic rate equations and physical activity factors with the intention of estimating the energy expenditure. Validity of reported energy intake assessed by multiple 24-hour recalls and estimated energy expenditure was tested using the Pearson correlation coefficient and the dependent t-test. The Pearson correlation test revealed low associations between energy intake and energy expenditure for boys (0.32) and girls (0.17), while the dependent t-test of the energy intake between the different measured occasions showed little difference, which could be explained by the high within participant variation and lower variation between the different participants. The low correlation coefficients showed that there was no association between reported energy intake and mean estimated energy expenditure; thus also no agreement. As a result, multiple 24-hour recalls measured over two years with only five 24-hour recalls did not give a valid measurement of the energy intake of black peri-urban adolescents. Lastly, the ratio of reported energy intake over energy expenditure was evaluated against the energy cut-off points, specifically calculated for age and ethnic group. It indicated that 85% of the participants underreported their energy intake. These results could have been influenced by the estimated basal metabolic rate equations that could have estimated the basal metabolic rate of this group incorrectly or could be due to the inability of the group to recall their physical activity levels correctly. Therefore it is recommended that further validity studies regarding dietary intake need to be performed on adolescents. It is suggested that energy expenditure as a reference method should be measured by using a calorimeter or the doubly labeled water method and then compared with the reported energy intake. Analysing different biochemical determinants of nutritional intake could also be used as an objective reference method to assess the validity of dietary data obtained from questionnaires. / Thesis (Ph.D. (Dietetics)--North-West University, Potchefstroom Campus, 2009.

Adolescence proves to be one of the most vulnerable development stages in the life of humans and therefore dietary assessment of this group is important, but complex. This is due to rapid growth during puberty and the development of new eating patterns that influence dietary intake. Adequate dietary intake in this age group is crucial, since adverse effects such as iron deficiency anemia, inadequate growth and dental caries can occur. Furthermore, dietary imbalance is a significant risk factor that can lay the groundwork for developing preventable complications in late adolescence and adult life such as non-communicable chronic diseases including obesity and diabetes mellitus type II and certain cancers, all leading causes of morbidity and mortality. Given the vulnerability of adolescents in terms of dietary intake, understanding their dietary intake is crucial. Dietary assessment of adolescents is influenced by social, physiological and psychological changes making accurate measurement of this group difficult. Hence, it is of fundamental importance to find a golden standard in terms of a dietary assessment method to use in this group. Several international studies investigated validity and reproducibility of the dietary intake of adolescents, measured with different dietary assessment methods. However, in South Africa only three validity and reproducibility studies have been published and none of them focused exclusively on adolescents. Since the validity of the results of dietary assessment methods of international studies cannot be extrapolated to South African black adolescents, this study emanated from the need to investigate whether multiple 24-hour recalls are valid and reproducible when used to assess the dietary intakes of black adolescents in a convenience sample of grade eight learners from a high school in a township in the North West Province. The study was nested in the multidisciplinary "Physical, Activity in the Young" (PLAY) study. Firstly, the optimal number of 24-hour recalls was determined by calculation of reproducibility coefficients for energy, selected nutrients and food groups. Results showed that four repeated 24-hour recalls provided the optimal reproducibility for black peri-urban South African adolescents. Secondly, the search for a reference method to compare energy intake against energy expenditure led to an investigation into basal metabolic rate equations and physical activity factors with the intention of estimating the energy expenditure. Validity of reported energy intake assessed by multiple 24-hour recalls and estimated energy expenditure was tested using the Pearson correlation coefficient and the dependent t-test. The Pearson correlation test revealed low associations between energy intake and energy expenditure for boys (0.32) and girls (0.17), while the dependent t-test of the energy intake between the different measured occasions showed little difference, which could be explained by the high within participant variation and lower variation between the different participants. The low correlation coefficients showed that there was no association between reported energy intake and mean estimated energy expenditure; thus also no agreement. As a result, multiple 24-hour recalls measured over two years with only five 24-hour recalls did not give a valid measurement of the energy intake of black peri-urban adolescents. Lastly, the ratio of reported energy intake over energy expenditure was evaluated against the energy cut-off points, specifically calculated for age and ethnic group. It indicated that 85% of the participants underreported their energy intake. These results could have been influenced by the estimated basal metabolic rate equations that could have estimated the basal metabolic rate of this group incorrectly or could be due to the inability of the group to recall their physical activity levels correctly. Therefore it is recommended that further validity studies regarding dietary intake need to be performed on adolescents. It is suggested that energy expenditure as a reference method should be measured by using a calorimeter or the doubly labeled water method and then compared with the reported energy intake. Analysing different biochemical determinants of nutritional intake could also be used as an objective reference method to assess the validity of dietary data obtained from questionnaires. / Thesis (Ph.D. (Dietetics)--North-West University, Potchefstroom Campus, 2009.

No description available.

Obesity research remains a high priority worldwide, given the sustained high levels of obesity (body mass index ≥30 kg/m2) and class III obesity (body mass index ≥40 kg/m2) across many demographic groups. One component of obesity research is the study of how diet can contribute to obesity, and thus it is crucial to evaluate how existing dietary assessment methods perform for people with obesity, and to develop or refine methods to enhance their accuracy. Researchers should be prepared to include more individuals with obesity and class III obesity, a growing demographic, in studies that assess dietary intake. With the inclusion of these groups, it is vital to consider the potential impact of weight bias and weight stigma on dietary research. Weight bias is negative attitudes and stereotypes about people with obesity, while weight stigma is how these attitudes collectively devalue people with obesity, which could result in acts of discrimination. This dissertation: 1) defined the issues of weight bias and weight stigma, and how they affect dietetics practice, including research, 2) determined the representation of participants with class III obesity in studies validating self-reported measures of dietary assessment using doubly-labeled water, and 3) explored how weight bias and weight stigma might impact misreporting of energy intake among people with overweight and obesity. Findings include that: 1) weight bias and weight stigma are important issues when working with people with obesity, and dietetics professionals can address these in many areas of practice; 2) in studies validating self-reported dietary assessment methods using doubly-labeled water, people with class III obesity are underrepresented, and thus the validity of existing methods to assess diet among people with class III obesity requires further research; 3) in a sample of participants with self-reported overweight and obesity, previous experiences of weight stigma were common, though internalized weight bias, weight bias toward others, and experiences of weight stigma were not predictive of the validity of energy intake reporting. Researchers should consider the potential impact of weight stigma on recruitment, retention, and participant experience when working with participants with obesity. / Doctor of Philosophy / One part of obesity research is the study of how food intake can contribute to obesity. It is crucial to evaluate how well existing methods perform that measure what and how much people eat, especially in people with obesity. As obesity levels rise, researchers should be prepared to include more people with obesity (body mass index ≥30 kg/m2) and class III obesity (body mass index ≥40 kg/m2) in studies that measure dietary intake. When including people with obesity in studies, it is important to consider the potential impact of weight bias and weight stigma on nutrition research. Weight bias is the idea of negative attitudes and stereotypes about people with obesity, while weight stigma is how these attitudes collectively devalue people with obesity. This dissertation 1) defined the issues of weight bias and weight stigma, and how they affect dietetics practice, including nutrition research, 2) determined the representation of people with class III obesity in studies testing the accuracy of methods collecting information about food intake and 3) explored how weight bias and weight stigma might affect how accurately people with overweight and obesity report the number of calories that they eat. This work found: 1) weight bias and weight stigma are important emerging issues when working with people with obesity, and dietetics professionals can address weight bias and weight stigma in many areas of practice; 2) in studies testing the accuracy of measures that collect food information, people with class III obesity are underrepresented, and more research is needed to determine how accurate these measures are in this group; and 3) in a group of people with overweight and obesity, previous experiences of weight stigma were common, though internalized weight bias, weight bias toward others, and experiences of weight stigma did not predict how well a person reported their calorie intake. Future studies should include more people with class III obesity. Researchers should consider how weight stigma might affect a person's willingness to participate in nutrition studies. Minimizing weight stigma in research may decrease participation barriers for people with obesity in research about nutrition, weight, and health.