Spicy Food Consumption and Risk of Uninvestigated Heartburn in Isfahani Adults.

BACKGROUND/OBJECTIVE: Dietary recommendations for the consumption of spicy foods in uninvestigated heartburn are still under debate. We examine the association between spicy food consumption and the prevalence of uninvestigated heartburn in a large sample of Iranian adults. METHODS: This cross-sectional study was conducted among 4,633 Iranian adults living in Isfahan (2,046 men, 2,587 women) in 2010. The average daily intake of spicy foods was estimated using a dietary habit questionnaire. Uninvestigated heartburn was defined, using a validated Rome III questionnaire, as the presence of heartburn sometimes, often or always during the last 3 months. RESULTS: Uninvestigated heartburn was prevalent in 23.8% (n = 1,103) of participants. After controlling for potential confounders, including dietary behaviors and body mass index, men consuming spicy foods ≥10 times/week were 2.63 times more likely to have uninvestigated heartburn (95% CI:1.28-5.36) compared with those who never consumed spicy foods. Also, those men with the highest consumption of spicy foods were 3 times more likely to experience heartburn frequently (95% CI 1.44-6.39) compared with men with the lowest intake. No overall significant associations were found between the consumption of spicy foods and uninvestigated heartburn, including the frequency and severity of heartburn, in women. When the analysis was restricted to those with uninvestigated heartburn, no significant associations were found between consumption of spicy foods and frequency of heartburn either in men or women. CONCLUSION: The present findings suggest that high consumption of spicy foods was associated with a greater risk of uninvestigated heartburn in men, but not in women. Further studies, particularly of a prospective nature, are needed to confirm our findings, as well as underlying mechanisms.

A Dish-based Semi-quantitative Food Frequency Questionnaire for Assessment of Dietary Intakes in Epidemiologic Studies in Iran: Design and Development.

BACKGROUND: Earlier forms of food frequency questionnaire (FFQ) used in Iran have extensive lists of foods, traditional categories and food-based design, mostly with the interviewer-administered approach. The aim of the current paper is to describe the development of a dish-based, machine-readable, semi-quantitative food frequency questionnaire (DFQ). METHODS: Within the framework of the Study on the Epidemiology of Psychological, Alimentary Health and Nutrition project, we created a novel FFQ using Harvard FFQ as a model. RESULTS: THE FOLLOWING STEPS WERE TAKEN TO DEVELOP THE QUESTIONNAIRE: Construction of a list of commonly consumed Iranian foods, definition of portion sizes, design of response options for consumption frequency of each food item and finally a pilot test of the preliminary DFQ. From a comprehensive list of foods and mixed dishes, we included those that were nutrient-rich, consumed reasonably often or contributed to between-person variations. We focused on mixed dishes, rather than their ingredients, along with foods. To shorten the list, the related food items or mixed dishes were categorized together in one food group. These exclusions resulted in a list of 106 foods or dishes in the questionnaire. The portion sizes used in the FFQ were obtained from our earlier studies that used dietary recalls and food records. The frequency response options for the food list varied from 6-9 choices from "never or less than once a month" to "12 or more times per day". CONCLUSIONS: The DFQ could be a reasonable dietary assessment tool for future epidemiological studies in the country. Validation studies are required to assess the validity and reliability of this newly developed questionnaire.

Moderate replacement of carbohydrates by dietary fats affects features of metabolic syndrome: a randomized crossover clinical trial.

OBJECTIVE: Earlier studies on the management of metabolic syndrome (MetS) have mostly focused on very low carbohydrate diets, whereas long-term adherence to such diets is difficult for apparently healthy people. The aim of this study was to examine the effects of moderate replacement of carbohydrates by dietary fats on insulin resistance and features of MetS among women. METHODS: This randomized crossover clinical trial was performed with 30 overweight or obese (body mass index [BMI] > 25 kg/m(2)) women with MetS. After a 2-wk run-in period, participants were randomly assigned to consume either a calorie-restricted high-carbohydrate (HC) diet (60%-65% of energy from carbohydrates and 20%-25% from fats) or a calorie-restricted moderately restricted carbohydrate (MRC) diet (43%-47% of total calories as carbohydrate and 36%-40% as dietary fats) for 6 wk. Protein contents of both diets were 15% to 17% of total energy. A 2-wk washout period was applied following which participants were crossed over to the alternate treatment arm for an additional 6 wk. Anthropometric, blood pressure, and biochemical measurements were performed before and after each phase of intervention. RESULTS: Mean age and BMI of study participants was 42.4 y and 33 kg/m(2), respectively. A trend toward greater reduction in waist (-3.9 versus -2.6 cm; P = 0.07) and hip circumferences (-2.7 versus -1.5 cm; P = 0.07) as well as serum triglyceride (TG) levels (-31.3 versus 0.13 mg/dL; P = 0.07) was observed after consumption of an MRC diet compared with an HC diet. The TG to high-density lipoprotein cholesterol (HDL-C) ratio had a tendency to improve with the MRC diet rather than the HC diet (-0.9 versus -0.1; P = 0.06). Consumption of the MRC diet resulted in a greater reduction of systolic blood pressure (-8.93 versus -2.97 mm Hg; P = 0.06) and diastolic blood pressure (-12.7 versus -1.77 mm Hg; P = 0.001) compared with the HC diet. The prevalence of MetS was significantly decreased following the consumption of the MRC diet (P = 0.03). The two diets were not significantly different in terms of their effect on fasting plasma glucose, serum HDL-C, low-density lipoprotein cholesterol, and total cholesterol, insulin levels, and Homeostasis Model Assessment-Insulin Resistance. CONCLUSION: Moderate replacement of carbohydrates by dietary fats was not associated with statistically different changes in fasting plasma glucose, insulin, or atherogenic dyslipidemia among individuals with the metabolic syndrome; however, it resulted in decreased diastolic blood pressure and lower prevalence of the metabolic syndrome.

Comparative effects of carbohydrate versus fat restriction on serum levels of adipocytokines, markers of inflammation, and endothelial function among women with the metabolic syndrome: a randomized cross-over clinical trial.

BACKGROUND AND AIMS: Despite the efficacy of low-carbohydrate diets in the management of metabolic syndrome (MetS), it remains unknown if these favorable effects are mediated through changes in inflammation and endothelial dysfunction. We aimed to assess the effects of moderate substitution of dietary fats for carbohydrates on serum levels of adipocytokines, inflammatory indices, and biomarkers of endothelial function among women with the MetS. METHODS: In a randomized cross-over clinical trial, 30 overweight or obese (BMI >25) women with the MetS were randomly allocated to follow either a high-carbohydrate (HC) (60-65% carbohydrates, 20-25% fats) diet or a moderately restricted carbohydrate (MRC) (43-47% carbohydrate, 36-40% fats) diet, each for 6 weeks. After a 2-week washout period, individuals were switched to the alternate diet for an additional 6 weeks. In a fasted state, markers of inflammation [high-sensitivity C-reactive protein (hs-CRP), high-sensitivity interleukin-6 (hs-IL-6), high-sensitivity tumor necrosis factor-α (hs-TNF-α), and serum amyloid A (SAA)], endothelial function [E-selectin, serum intercellular adhesion molecule 1 (sICAM-1), and serum vascular cell adhesion molecule 1 (sVCAM-1)], and adipocytokines (leptin and adiponectin) were measured in both study arms at baseline and after 6 weeks. RESULTS: Consumption of an HC diet was associated with increased levels of SAA (3.27 ± 1.22 µg/ml) and decreased levels of adiponectin (-1.68 ± 2.30 ng/ml), while consumption of an MRC diet did not result in such unfavorable effects. Serum concentrations of leptin were reduced by the HC diet (p = 0.02), while they were not affected by the MRC diet. Changes in serum leptin levels were not significant between the two diets (p = 0.09). Serum concentrations of hs-CRP, hs-TNF-α, and IL-6 were not influenced by either diet. No significant differences between the two diets were found in terms of their effect on sICAM-1 and sVCAM-1 concentrations. Adherence to both diets resulted in a 9 ng/ml decrease in serum E-selectin levels (p < 0.05 for both). CONCLUSIONS: Partial replacement of dietary carbohydrates by unsaturated fats prevents the increased levels of markers of systemic inflammation among women with the MetS.

Dietary choline and betaine intakes and risk of cardiovascular diseases: review of epidemiological evidence.

BACKGROUND: Cardiovascular diseases (CVD) are the most important causes of human mortality in the world. Higher intakes of choline and betaine have been shown to be associated with lower plasma homocysteine levels (the putative CVD risk factor). This study aimed to review the evidence on the association between dietary intakes of choline and betaine and traditional/novel CVD risk factors. METHODS: We searched in PubMed website from 1990 to 2009, with the use of following keywords: "dietary choline and betaine, cardiovascular diseases, metabolic syndrome, inflammation". The cross-sectional and prospective studies as well as the clinical trials were recruited in this investigation. RESULTS: Dietary intakes of "choline"/"choline and betaine" were not significantly associated with CVD risk; however, the higher intakes of choline and betaine were associated with higher serum concentrations of CRP, IL-6 and TNF-α. Individuals with high plasma choline levels were obese and had elevated plasma triglycerides, HDL and non-HDL cholesterol levels; whereas high plasma betaine levels were inversely associated with these biochemical markers. Both choline and betaine supplementation resulted in increased blood lipid profiles. CONCLUSION: Although dietary intakes of choline and betaine were not significantly associated with CVD incidence, the long-term consumption of these nutrients have been shown to prevent CVD mortality by decreasing inflammation and other risk factors.