The effects of L-carnitine supplementation on glycemic control: a systematic review and meta-analysis of randomized controlled trials

The findings of trials investigating the effect of L-carnitine administration on glycemic control are controversial. This meta-analysis of randomized controlled trials (RCTs) was performed to explore the effects of L-carnitine intake on glycemic control. Two authors independently searched electronic databases including MEDLINE, EMBASE, Cochrane Library, Web of Science, PubMed and Google scholar from 1990 until February 2019, in order to find relevant RCTs. 37 studies with 44 effect sizes met the inclusion criteria and were eligible for the meta-analysis. L-carnitine supplementation resulted in a significant reduction in fasting plasma glucose (FPG) (WMD: -4.57; 95 % CI: -6.88, -2.25), insulin (WMD: -1.21; 95 % CI: -1.85, -0.57), homeostatic model assessment for insulin resistance (HOMA-IR) (WMD: -0.67; 95 % CI: -0.90, -0.44) and HbA1C concentrations (WMD: -0.30; 95 % CI: -0.47, -0.13). L-Carnitine supplementation significantly reduced FPG, insulin, HOMA-IR, and HbA1c levels

Smoking and dietary inadequacy among Inuvialuit women of child bearing age in the Northwest Territories, Canada

Objective The prevalence of smoking in Aboriginal Canadians is higher than non-Aboriginal Canadians, a behavior that also tends to alter dietary patterns. Compared with the general Canadian population, maternal smoking rates are almost twice as high. The aim of this study was to compare dietary adequacy of Inuvialuit women of childbearing age comparing smokers versus non-smokers. Research methods & procedures A cross-sectional study, where participants completed a culturally specific quantitative food frequency questionnaire. Non-parametric analysis was used to compare mean nutrient intake, dietary inadequacy and differences in nutrient density among smokers and non-smokers. Multiple logistic regression analyses were performed for key nutrients inadequacy and smoking status. Data was collected from three communities in the Beaufort Delta region of the Northwest Territories, Canada from randomly selected Inuvialuit women of childbearing age (19-44 years). Results Of 92 participants, 75% reported being smokers. There were no significant differences in age, BMI, marital status, education, number of people in household working and/or number of self employed, and physical activity between smokers and non-smokers. Non-parametric analysis showed no differences in nutrient intake between smokers and non-smokers. Logistic regression however revealed there was a positive association between smoking and inadequacies of vitamin C (OR = 2.91, 95% CI, 1.17-5.25), iron (OR = 3.16, 95% CI, 1.27-5.90), and zinc (OR = 2.78, 95% CI, 1.12-4.94). A high percentage of women (>60%), regardless of smoking status, did not meet the dietary recommendations for fiber, vitamin D, E and potassium. Conclusions This study provides evidence of inadequate dietary intake among Inuvialuit of childbearing age regardless of smoking behavior

Ovarian cancer and diet: from nutrients to lifestyle

Abstract Ovarian cancer is the 6th most common cancer in women worldwide and mortality from this cancer is high, because early diagnosis is difficult (Sankaranarayanan et al. 2006). Thus, identification of modifiable factors contributing to its aetiology is important in reducing the burden of a very fatal form of women’s cancer. The overall aim of this thesis was to investigate the association between diet and ovarian cancer risk within the context of a framework ‘from nutrients to lifestyle’. The study examined dietary and lifestyle factors that had not previously been investigated comprehensively in four main areas: nutrients (retinol, beta-carotene, vitamins E, C, and B), foods (fruit, vegetables, dairy products, eggs, meat and liver), diet patterns and lifestyle (smoking, alcohol, and body-mass-index). The study used the data from two population-based case-control studies of women aged 18-79 years conducted in Australia 10 years apart; the Survey of Women’s Health (SWH, 1990-1993) involves 683 cases and 777 controls, and the Australian Ovarian Cancer Study (AOCS, 2002-2005) includes 1329 cases and 1397 controls. Cases were recruited from gynaecological oncology treatment centres and controls were selected at random from the electoral roll. Detailed information on non-dietary risk factors was obtained using a questionnaire and dietary information was obtained via a semi-quantitative food frequency questionnaire. Multivariable-adjusted odds ratios (ORs) (adjusting for age, parity, oral contraceptive use, education, and energy intake) for ovarian cancer risk were estimated separately for each study with logistic regression modelling and weighted pooled risk estimates for the two studies were calculated using fixed-effects models. Principal components analysis of around 40 food groups was performed to identify dietary patterns in each study separately. There was an increased risk of ovarian cancer associated with retinol intake in both studies (combined OR for the highest vs. lowest quartile =1.42, 95%CI 1.19-1.69), while intake of beta-carotene was inversely related to cancer risk (combined OR=0.80, 95%CI 0.67-0.96). The associations between retinol and beta-carotene and risk appeared to be independent. Liver was also associated with an increased risk; however this association seemed to be explained by the high levels of retinol in liver. Dairy products and eggs are other good sources of retinol, but no clear relations were seen and additional adjustment for saturated fat further attenuated the associations. High vitamin E intake (combined OR=0.73, 95%CI 0.61-0.87) was associated with a decreased risk, but no overall association was seen for vitamin C (combined OR=1.06, 95%CI 0.89-1.27). It is noteworthy that vitamin C seemed to be more beneficial for current smokers than for never/past smokers. For the B vitamins, a significant inverse association was apparent only for niacin intake (combined OR=0.69, 95%CI 0.58-0.82). While there was no association between cancer risk and sources of niacin such as total meat and red meat, other niacin-rich foods such as poultry (combined OR=0.77, 95%CI 0.66-0.89) and fish (combined OR=0.83, 95%CI 0.71-0.97) were significantly inversely associated with risk. In contrast to poultry and fish, high consumption of processed meat was associated with a 24% increase in risk (combined OR=1.24, 95%CI 1.06-1.45). Total fruit (combined OR=0.75, 95%CI 0.60-0.94) and total vegetables (combined OR=0.69, 95%CI 0.52-0.92), specifically cruciferous vegetables (combined OR=0.79, 95%CI 0.63-0.98) and green leafy vegetables (combined OR=0.79, 95%CI 0.67-0.94), were associated with a modestly decreased risk, whereas the inverse association between red/yellow vegetables and risk did not quite reach statistical significance (combined OR=0.84, 95%CI 0.64-1.08). High fruit intake was, like vitamin C intake, somewhat more beneficial for current/past smokers than for never smokers. Exclusion of women who took dietary supplements did not substantially change the observed associations between nutrients and risk. Three major eating patterns were identified: ‘snacks and alcohol’, ‘fruit and vegetable’, and ‘meat and fat’. Significant inverse associations between the snacks and alcohol pattern and risk were attenuated after further adjustment for white/red wine intake in both studies; it thus appeared that the observed association was at least partly due to wine intake. A significant association between the fruit and vegetable pattern and risk was seen only in the more recent study. A diet characterized by high meat and fat was associated with an increased risk of ovarian cancer, although the observed association was stronger in the SWH There was no evidence that the associations between diet pattern and cancer risk varied by women’s lifestyle. Although there was some variation in the analyses stratified by the histologic subtype of ovarian cancer, no consistent patterns of variation were observed for either study. These findings provide additional evidence that a healthy diet defined by high intake of fruit, vegetables, particularly cruciferous and green leafy vegetables, white meat and fish and low in meat and fat, especially processed meats might be beneficial against ovarian cancer

Dietary adequacies among South African adults in rural KwaZulu-Natal.

BACKGROUND: Food quality, determined by micronutrient content, is a stronger determinant of nutritional status than food quantity. Health concerns resulting from the co-existence of over-nutrition and under-nutrition in low income populations in South Africa have been fully recognized in the last two decades. This study aimed to further investigate dietary adequacy amongst adults in rural KwaZulu-Natal, by determining daily energy and nutrient intakes, and identifying the degree of satisfaction of dietary requirements. METHODS: Cross-sectional study assessing dietary adequacy from 24-hour dietary recalls of randomly selected 136 adults in Empangeni, KwaZulu-Natal, South Africa. RESULTS: Results are presented for men (n = 52) and women (n = 84) 19-50 and >50 years old. Mean energy intake was greatest in women >50 years (2852 kcal/day) and exceeded Dietary Reference Intake's for both men and women, regardless of age. Mean daily energy intake from carbohydrates was 69% for men and 67% for women, above the Dietary Reference Intake range of 45-65%. Sodium was also consumed in excess, and the Dietary Reference Intakes of vitamins A, B12, C, D, and E, calcium, zinc and pantothenic acid were not met by the majority of the population. CONCLUSION: Despite mandatory fortification of staple South African foods, micronutrient inadequacies are evident among adults in rural South African communities. Given the excess caloric intake and the rising prevalence of obesity and other non-communicable diseases in South Africa, a focus on diet quality may be a more effective approach to influence micronutrient status than a focus on diet quantity

Understanding the social determinants of health among Indigenous Canadians: priorities for health promotion policies and actions

Background: Indigenous Canadians have a life expectancy 12 years lower than the national average and experience higher rates of preventable chronic diseases compared with non-Indigenous Canadians. Transgenerational trauma from past assimilation policies have affected the health of Indigenous populations. Objective: The purpose of this paper is to comprehensively examine the social determinants of health (SDH), in order to identify priorities for health promotion policies and actions. Design: We undertook a series of systematic reviews focusing on four major SDH (i.e. income, education, employment, and housing) among Indigenous peoples in Alberta, following the protocol Preferred Reporting Items for Systematic Reviews and Meta-Analysis-Equity. Results: We found that the four SDH disproportionately affect the health of Indigenous peoples. Our systematic review highlighted 1) limited information regarding relationships and interactions among income, personal and social circumstances, and health outcomes; 2) limited knowledge of factors contributing to current housing status and its impacts on health outcomes; and 3) the limited number of studies involving the barriers to, and opportunities for, education. Conclusions: These findings may help to inform efforts to promote health equity and improve health outcomes of Indigenous Canadians. However, there is still a great need for in-depth subgroup studies to understand SDH (e.g. age, Indigenous ethnicity, dwelling area, etc.) and intersectoral collaborations (e.g. community and various government departments) to reduce health disparities faced by Indigenous Canadians

Distribution of the range of dietary adequacy of energy and key micronutrients among men and women in rural KwaZulu-Natal, South Africa.

<p>DRI, Dietary Reference Intake.</p>a<p>Acceptable Macronutrient Distribution Ranges (AMDR) for energy and Estimated Average Requirement (EAR) for nutrients.</p>b<p>As retinol activity equivalents;</p>c<p>As α-tocopherol.</p

Characteristics of rural men and women in KwaZulu-Natal, South Africa (n = 136).

<p>SD, standard deviation,</p>a<p>Self reported information.</p

Mean (SD) daily energy and nutrient intake among South African adults in rural KwaZulu-Natal.

<p>CHO, carbohydrates; DRI, dietary reference intake; SD, standard deviation; ^a DRI for men >50 years 25 g/day and for women >50 years old 21 g/day; ^bAI for men >50 years 14 g/day and for women >50 years old 11 g/day; ^cAs low as possible; ^dAs retinol activity equivalents (RAEs); ^eDRI for men >50 years 1.7 mg/d; ^f DRI for women >50 years old 8 mg/day; ^gAs cholecalciferol; ^hAs α-tocopherol; ⁱDRI for women >50 years old 1200 g/day; ^jDRI for men and women >50 years old 1300 mg/day.</p

Development of a Quantitative Food Frequency Questionnaire for Use among the Yup'ik People of Western Alaska

<div><p>Alaska Native populations are experiencing a nutrition transition and a resulting decrease in diet quality. The present study aimed to develop a quantitative food frequency questionnaire to assess the diet of the Yup'ik people of Western Alaska. A cross-sectional survey was conducted using 24-hour recalls and the information collected served as a basis for developing a quantitative food frequency questionnaire. A total of 177 males and females, aged 13-88, in six western Alaska communities, completed up to three 24-hour recalls as part of the Alaska Native Dietary and Subsistence Food Assessment Project. The frequency of the foods reported in the 24-hour recalls was tabulated and used to create a draft quantitative food frequency questionnaire, which was pilot tested and finalized with input from community members. Store-bought foods high in fat and sugar were reported more frequently than traditional foods. Seven of the top 26 foods most frequently reported were traditional foods. A 150-item quantitative food frequency questionnaire was developed that included 14 breads and crackers; 3 cereals; 11 dairy products; 69 meats, poultry and fish; 13 fruit; 22 vegetables; 9 desserts and snacks; and 9 beverages. The quantitative food frequency questionnaire contains 39 traditional food items. This quantitative food frequency questionnaire can be used to assess the unique diet of the Alaska Native people of Western Alaska. This tool will allow for monitoring of dietary changes over time as well as the identification of foods and nutrients that could be promoted in a nutrition intervention program intended to reduce chronic disease.</p></div