The purpose of this cluster-randomized equivalence trial was to investigate the effectiveness of two supplemental foods in children with moderate malnutrition by comparing: (i) time to recovery by survival analysis, and (ii) recovery rates (after 16 weeks of treatment). A total of 2,600 children 6-60 months of age were randomized by cluster (district) to receive 16 weeks of conventional (Corn-Soya Blended flour, CSB) or intervention (Ready-to-Use Supplemental Food, RUSF) foods. Overall, time to recovery from malnutrition (mean 74 days) and recovery rates (mean 76%) were equivalent with both foods. The time to recovery outcomes were equivalent, independent of location, whereas the recovery rate in children receiving CSB was significantly higher in the more food insecure southern region. Intra-household food sharing was significantly higher in the CSB group compared to RUSF. Overall, the response to the two different supplemental foods was equivalent for the treatment of moderately malnourished children in Ethiopia.

Gestational Diabetes Mellitus develops in 3.7-18% of Canadian women, and can cause serious maternal-fetal complications. Low-GI foods have been shown to increase β-cell function in subjects with impaired glucose tolerance. Theoretically, this effect should improve glucose tolerance and reduce the risk of gestational hyperglycemia. Thus, we aimed to explore the effects of a low-GI diet on glucose challenge test (GCT) results in women at risk for GDM. Women were randomized to receive education during pregnancy focused on incorporation of low- or medium- to high-GI foods. Key foods were provided to assist compliance. Information was obtained from medical records and questionnaires. Ninety-four (94) women completed the study. After adjustment for confounding variables, there was no significant difference in GCT values between intervention groups. Results suggest that low-GI foods do not affect blood glucose control during pregnancy.

Individuals with abdominal obesity are at higher risk for developing type 2 diabetes, predisposing cardiovascular events and insulin resistance. Low glycemic index (GI) diets may be beneficial in the management of insulin resistance. Insulin resistance is associated with increased intramyocellular lipid (IMCL) content as measured by proton nuclear magnetic resonance spectroscopy (1H-MRS). The primary objective of this thesis was to determine whether a low GI diet can improve insulin sensitivity by reducing IMCL of skeletal muscle. One hundred and twenty-one male and female participants aged 30 to 70 years (mean+SD, 53+10)) with abdominal obesity, entered a 4 to 6 week weight-maintaining, low-fat dietary advice run-in phase. Of the 121 eligible participants, 95 completed the run-in phase and were randomly assigned to either a low-GI (LGID, n=48) or high-GI diet (HGID, n=47) for 24 weeks. Participants underwent a 75g oral glucose tolerance test (OGTT) and had soleus-muscle IMCL measured by 1H-MRS at the beginning and end of the intervention period. Insulin sensitivity was assessed by the homeostatic model assessment index (HOMA) and the insulinogenic index (ISI) was calculated for insulin secretion. At the end of the run-in phase, there were significant reductions in serum total-, LDL-, and HDL-cholesterol (all, p<0.0001) and an increase in fasting plasma glucose (p<0.05). In 57 participants who wore a continuous glucose monitoring system for 24 hours during the run-in period, a total of 30% (p<0.001) of the variation in the incremental area under the blood glucose curve after self-selected breakfast meals was explained by GI. After 24 weeks, diet GI was significantly lower in the LGID than HGID group (55.5+3.1 vs 63.9+3.1, p<0.0001). Plasma glucose 60 minutes after the OGTT was significantly lower on the LGID than at baseline (p<0.05) and there was a non-significant trend towards an increase in ISI (p=0.07). On the HGID, ISI increased significantly from baseline (p<0.01). It is concluded that the LGID reduced 60 minute plasma glucose but did not significantly affect IMCL or insulin sensitivity in individuals with abdominal obesity.

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.

The provision of free or low cost meals is an integral component of community services working to address problems of poverty and homelessness in Canada. However, there has been little systematic examination of how they function relative to clients&rsquo; nutrition needs. The objective of this research was to investigate the scope and nature of meal programs by examining an inventory of charitable food provisioning activities, created between 2010 and 2011, in five Canadian cities. Of 290 agencies offering meal programs, 548000 meals were served every month. However, service scheduling varied throughout the week, and the majority of agencies were reliant on volunteer labour, donated food supplies, and experienced difficulties managing the current demand for food assistance. Findings from this study highlight the strengths and limitations of the current food provisioning system and a need to improve the capacity of agencies to respond to populations experiencing food insecurity in Canada.

Individuals with abdominal obesity are at higher risk for developing type 2 diabetes, predisposing cardiovascular events and insulin resistance. Low glycemic index (GI) diets may be beneficial in the management of insulin resistance. Insulin resistance is associated with increased intramyocellular lipid (IMCL) content as measured by proton nuclear magnetic resonance spectroscopy (1H-MRS). The primary objective of this thesis was to determine whether a low GI diet can improve insulin sensitivity by reducing IMCL of skeletal muscle. One hundred and twenty-one male and female participants aged 30 to 70 years (mean+SD, 53+10)) with abdominal obesity, entered a 4 to 6 week weight-maintaining, low-fat dietary advice run-in phase. Of the 121 eligible participants, 95 completed the run-in phase and were randomly assigned to either a low-GI (LGID, n=48) or high-GI diet (HGID, n=47) for 24 weeks. Participants underwent a 75g oral glucose tolerance test (OGTT) and had soleus-muscle IMCL measured by 1H-MRS at the beginning and end of the intervention period. Insulin sensitivity was assessed by the homeostatic model assessment index (HOMA) and the insulinogenic index (ISI) was calculated for insulin secretion. At the end of the run-in phase, there were significant reductions in serum total-, LDL-, and HDL-cholesterol (all, p<0.0001) and an increase in fasting plasma glucose (p<0.05). In 57 participants who wore a continuous glucose monitoring system for 24 hours during the run-in period, a total of 30% (p<0.001) of the variation in the incremental area under the blood glucose curve after self-selected breakfast meals was explained by GI. After 24 weeks, diet GI was significantly lower in the LGID than HGID group (55.5+3.1 vs 63.9+3.1, p<0.0001). Plasma glucose 60 minutes after the OGTT was significantly lower on the LGID than at baseline (p<0.05) and there was a non-significant trend towards an increase in ISI (p=0.07). On the HGID, ISI increased significantly from baseline (p<0.01). It is concluded that the LGID reduced 60 minute plasma glucose but did not significantly affect IMCL or insulin sensitivity in individuals with abdominal obesity.

Objective: This thesis aims to construct a framework for studying vitamin D deficiency in young Canadian children. Methods: A practice based research network was created to collect vitamin D data from children 1-5 years of age in Toronto, Canada (TARGet Kids!). A cross-sectional pilot study was completed and a larger study proposed to determine the prevalence and predictors of low vitamin D. Results: The prevalence of low vitamin D (<50nmol/L) in the pilot study was 32% (29/92, 95% CI: 22-42%). Using multivariable linear regression, lower vitamin D level was associated with lower milk volume, higher BMI and watching TV during snacks. A larger study involving 2400 children 1-5 years of age has been proposed. Interpretation: Pilot data has suggested that 30-80% of toddlers in this setting have low vitamin D. A study to clarify these findings and form the basis of a large longitudinal vitamin D cohort has been proposed.

Objective: This thesis aims to construct a framework for studying vitamin D deficiency in young Canadian children. Methods: A practice based research network was created to collect vitamin D data from children 1-5 years of age in Toronto, Canada (TARGet Kids!). A cross-sectional pilot study was completed and a larger study proposed to determine the prevalence and predictors of low vitamin D. Results: The prevalence of low vitamin D (<50nmol/L) in the pilot study was 32% (29/92, 95% CI: 22-42%). Using multivariable linear regression, lower vitamin D level was associated with lower milk volume, higher BMI and watching TV during snacks. A larger study involving 2400 children 1-5 years of age has been proposed. Interpretation: Pilot data has suggested that 30-80% of toddlers in this setting have low vitamin D. A study to clarify these findings and form the basis of a large longitudinal vitamin D cohort has been proposed.

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.

The provision of free or low cost meals is an integral component of community services working to address problems of poverty and homelessness in Canada. However, there has been little systematic examination of how they function relative to clients&rsquo; nutrition needs. The objective of this research was to investigate the scope and nature of meal programs by examining an inventory of charitable food provisioning activities, created between 2010 and 2011, in five Canadian cities. Of 290 agencies offering meal programs, 548000 meals were served every month. However, service scheduling varied throughout the week, and the majority of agencies were reliant on volunteer labour, donated food supplies, and experienced difficulties managing the current demand for food assistance. Findings from this study highlight the strengths and limitations of the current food provisioning system and a need to improve the capacity of agencies to respond to populations experiencing food insecurity in Canada.