Evaluation of risk factors for insulin resistance: a cross sectional study among employees at a private university in Lebanon.

BACKGROUND: Worldwide, the prevalence of insulin resistance ranges from 15.5 to 46.5%, among adults. Lebanon reported one of the highest rates reaching 44.6%. The literature suggests an association between dairy product consumption and insulin resistance, however results are inconclusive. To our knowledge, no study examined this association in the Middle Eastern Region. The aim of the study was to investigate the prevalence of insulin resistance among a sample of Lebanese adults, to identify its risk factors depending on gender, and to evaluate the association between insulin resistance and dairy products consumption. METHODS: A cross-sectional study was conducted among employees at Notre Dame University - Louaize. Four questionnaires were administered including a background and International Physical Activity Questionnaire short form questionnaires, food frequency questionnaire and a 24 h recall. Bioelectric Impedance Analysis (BIA) was used to measure percent body fat (PBF). Homeostatic Model Assessment for Insulin Resistance (HOMA-IR) was used to quantify insulin resistance. A person with HOMA-IR ≥ 2.5 was considered as insulin resistant. Statistical analyses were performed using the Statistical Package for Social Sciences version 23 for Windows. P < 0.05 was considered statistically significant. RESULTS: Out of 286 study participants, 38.0% were insulin resistant. Average dairy product intake in the total sample was 2.2 ± 1.0 servings per day. Among males, the odds of having insulin resistance were 3.9 times higher (95%CI 1.4-11.0; p = 0.009) for those having a risky waist circumference compared to those having a healthy waist circumference. Among females, being married (OR: 0.2, 95%CI 0.1-0.5; p = 0.002), PBF (OR: 1.2, 95%CI 1.0-1.3; p = 0.008) and hypertriglyceridemia (OR: 8.7, 95%CI: 2.1-35.9; p = 0.003) were associated with HOMA-IR, after controlling for confounders. Dairy intake was not associated with HOMA-IR neither among males (p = 0.777), nor among females (p = 0.968), after controlling for confounders. CONCLUSION: Dairy consumption was not associated with increased insulin resistance. More research focusing on the relationship between dairy intake and insulin resistance is needed, especially in the Arab and Middle-Eastern region. Future studies should examine the effect of different types of dairy products and the effect of different nutrients in dairy products on insulin resistance.

Vitamin D status and intake of lactating Inuit women living in the Canadian Arctic.

OBJECTIVE: To determine the prevalence and correlates of healthy vitamin D status in lactating Inuit women living in remote regions of the Arctic. DESIGN: Cross-sectional. SETTING: Households were selected randomly in thirty-six communities of Nunavut, Nunatsiavut and Inuvialuit Settlement Region. Dietary intake was assessed using a 24 h recall and an FFQ. Anthropometric measurements, household living conditions, supplement use and health status were assessed. In fasting samples, serum 25-hydroxyvitaimn D (25(OH)D) was measured using a chemiluminescent assay (LIAISON; Diasorin Inc.). SUBJECTS: Lactating Inuit women participating in the 2007-2008 International Polar Year Inuit Health Survey conducted in the months of August to October. RESULTS: Among participants (n 34), 8·8, 26·5 and 50·0 % had 25(OH)D concentrations at or above 75, 50 and 40 nmol/l, respectively. More than one-third of participants did not consume traditional foods during the previous day and only 11·3 % of total energy intake was derived from traditional foods. Only 14·7 % of the sample consumed the daily number of milk servings recommended by Canada's Food Guide (two servings) for First Nations, Inuit and Métis. Using multivariable logistic regression to examine 25(OH)D≥40 nmol/l, only higher body fat was inversely correlated with 25(OH)D concentration. CONCLUSIONS: The present study is the first to assess simultaneously vitamin D status and other known factors that affect it among lactating Inuit women living in remote communities in the Arctic. Healthy maternal vitamin D status was observed in 25 % of participants during the late summer and early autumn. This requires further assessment in a larger sample spanning more seasons.

Vitamin D status and body composition: a cross-sectional study among employees at a private university in Lebanon.

BACKGROUND: The prevalence of low vitamin D status is increasing globally, and Lebanon is not spared. The objectives of this study are to determine the prevalence and correlates of low vitamin D status, and to assess the association between percent body fat and vitamin D status, independently of obesity. METHODS: A cross-sectional study was performed on NDU employees. Data on dietary intake, physical activity, lifestyle, health status, and demographic variables were collected during a face-to-face interview. Anthropometric measures (weight, height and waist circumference) were measured and body composition was assessed using the bioelectrical impedance analysis (BIA) machine InBody 720 (Biospace, Seoul, Korea). The Nutritionist Pro diet analysis software version 31.0 was used to estimate dietary intake of vitamin D. Serum 25 hydroxyvitamin D (25(OH)D) was measured using enzyme linked immunosorbent assay kit (ELISA) (Calbiotech, Spring Valley, California, USA). Vitamin D status was assessed according to the National Osteoporosis Foundation (sufficiency: ≥ 75 nmol/L / ≥30 ng/mL) and the Institute of Medicine cut-offs (adequacy: ≥50 nmol/L / ≥20 ng/mL). Statistical analyses were performed by SPSS version 22. RESULTS: A total of 344 employees (50% Male) aged between 20 and 74 years participated in the study. More than half of the participants were overweight and obese. Mean serum vitamin D concentrations were 28.2 ± 13.9 ng/mL. Among participants, 37.5% of our study population had 25(OH)D ≥ 30 ng/mL, and 68.3% had 25(OH)D ≥ 20 ng/mL. Individuals with low vitamin D status had significantly higher percent body fat (PBF) (p < 0.005), and higher waist circumference (WC) (p = 0.012) than in the sufficient group, however BMI did not differ by vitamin D status. Logistic regression analysis indicated that a 1% increase in body fat increases the odds of having 25(OH)D ≤ 30 ng/mL by 8% while controlling for BMI and other confounders (p = 0.019). CONCLUSION: This study reinforces the need for regular screening for low vitamin D status in Lebanese adults, particularly individuals at risk, including those with high risk WC, high PBF, who work indoors and have low vitamin D intake, and recommending vitamin D supplementation if needed.

The relationship between hypovitaminosis D and metabolic syndrome: a cross sectional study among employees of a private university in Lebanon.

BACKGROUND: The prevalence of low vitamin D status and metabolic syndrome is increasing globally and in Lebanon. The objectives of this study are to assess the prevalence of metabolic syndrome (MetS) and its components (elevated triglycerides, low HDL, abdominal obesity defined by high waist circumference, hypertension, impaired fasting blood glucose) and investigate the association between serum 25-hydroxyvitamin D (25(OH)D) concentrations and MetS and its components among a sample of Lebanese adults. METHODS: A cross-sectional study was carried out on Notre Dame University employees. A background questionnaire, a short-form of the International Physical Activity Questionnaire and a food frequency questionnaire were administered. Participants were invited to the nutrition laboratory to gather data on anthropometric (height, waist circumference, weight, body composition and body mass index) and biochemical measurements (serum vitamin D, triglycerides, HDL and fasting blood glucose). Vitamin D status was assessed according to the Institute of Medicine cut-offs (inadequate or adequate: 25(OH)D < or ≥ 50 nmol/L).The definition of the Third Report of the National Cholesterol Education Program was used to identify individuals who had MetS. The data were analyzed using the SPSS version 22. P < 0.05 was considered statistically significant. RESULTS: A total of 344 participants (age range of 20 to 74 years) were included in the study. The prevalence of MetS was 23.5%. Among MetS components, central obesity was the most prevalent condition (50.6%), while the least prevalent was impaired fasting blood glucose (20.3%). The odds of having MetS were found to be 2.5 (95% CI 1.3-4.7) higher among those with inadequate vitamin D status, than among those with adequate vitamin D status while controlling for important confounders (age, marital status, education level, income, medical morbidity, smoking and percent body fat and gender). Among the components of MetS, only hypertriglyceridemia (OR: 2.4, 95%CI: 1.3-4.2) and low HDL (OR: 1.8, 95% CI: 1.0-3.0) were associated with inadequate vitamin D status while controlling for important confounders. CONCLUSIONS: Early identification and control of risk factors for cardiovascular diseases in the primary care level is needed, particularly among adults who have low vitamin D status, are obese, and have low income level.

Implications of the nutrition transition for vitamin D intake and status in Aboriginal groups in the Canadian Arctic.

Aboriginal Canadians have low intakes of vitamin D and are shifting away from consumption of traditional foods. Higher body mass index, skin pigmentation, and geographic latitude of residence further predispose Canadian Aboriginal populations to low vitamin D status. Low vitamin D status could compromise bone health and other health outcomes. Studies assessing vitamin D status of different Aboriginal groups are limited. The aim of this review is to examine the literature on vitamin D status and intakes of Canadian Aboriginal populations living in the Arctic. PubMed was searched for relevant articles published from 1983 to 2013. The prevalence of 25-hydroxy vitamin D deficiency ranged from 13.9% to 76.0% among children and adults in the summer. Furthermore, mean vitamin D intakes among all age groups were below the estimated average requirement. As vitamin D deficiency has been recently associated with chronic diseases, and Aboriginal populations living in the Arctic are at high risk for low vitamin D status, their vitamin D status should be assessed regularly across seasons.