This article was downloaded by: [New York University] On: 04 May 2015, At: 03:10 Publisher: Routledge Informa Ltd Registered in England and Wales Registered Number: 1072954 Registered office: Mortimer House, 37-41 Mortimer Street, London W1T 3JH, UK
Journal of the American College of Nutrition Publication details, including instructions for authors and subscription information: http://www.tandfonline.com/loi/uacn20
Association Between Dietary Patterns and Serum Leptin-to-Adiponectin Ratio in Apparently Healthy Adults a
a
b
Hamed Jafari-Vayghan MS , Ali Tarighat-Esfanjani PhD , Mohammad Asghari Jafarabadi PhD , a
a
a
Mehrangiz Ebrahimi-Mameghani PhD , Sevda Saleh Ghadimi PhD & Zahra Lalezadeh BS a
Nutrition Research Center, School of Nutrition, Tabriz University of Medical Sciences, Tabriz, IRAN b
Tabriz Health Services Management Research Center, School of Health, Tabriz University of Medical Sciences, Tabriz, IRAN Published online: 03 Feb 2015.
Click for updates To cite this article: Hamed Jafari-Vayghan MS, Ali Tarighat-Esfanjani PhD, Mohammad Asghari Jafarabadi PhD, Mehrangiz Ebrahimi-Mameghani PhD, Sevda Saleh Ghadimi PhD & Zahra Lalezadeh BS (2015) Association Between Dietary Patterns and Serum Leptin-to-Adiponectin Ratio in Apparently Healthy Adults, Journal of the American College of Nutrition, 34:1, 49-55, DOI: 10.1080/07315724.2014.880389 To link to this article: http://dx.doi.org/10.1080/07315724.2014.880389
PLEASE SCROLL DOWN FOR ARTICLE Taylor & Francis makes every effort to ensure the accuracy of all the information (the “Content”) contained in the publications on our platform. However, Taylor & Francis, our agents, and our licensors make no representations or warranties whatsoever as to the accuracy, completeness, or suitability for any purpose of the Content. Any opinions and views expressed in this publication are the opinions and views of the authors, and are not the views of or endorsed by Taylor & Francis. The accuracy of the Content should not be relied upon and should be independently verified with primary sources of information. Taylor and Francis shall not be liable for any losses, actions, claims, proceedings, demands, costs, expenses, damages, and other liabilities whatsoever or howsoever caused arising directly or indirectly in connection with, in relation to or arising out of the use of the Content. This article may be used for research, teaching, and private study purposes. Any substantial or systematic reproduction, redistribution, reselling, loan, sub-licensing, systematic supply, or distribution in any form to anyone is expressly forbidden. Terms & Conditions of access and use can be found at http:// www.tandfonline.com/page/terms-and-conditions
Original Research
Association Between Dietary Patterns and Serum Leptin-to-Adiponectin Ratio in Apparently Healthy Adults Hamed Jafari-Vayghan, MS, Ali Tarighat-Esfanjani, PhD, Mohammad Asghari Jafarabadi, PhD, Mehrangiz Ebrahimi-Mameghani, PhD, Sevda Saleh Ghadimi, PhD, Zahra Lalezadeh, BS Nutrition Research Center, School of Nutrition (H.J.-V., A.T.E., M.E.-M., S.S.G., Z.L.), and Tabriz Health Services Management Research Center, School of Health (M.A.J.),Tabriz University of Medical Sciences, Tabriz, IRAN
Downloaded by [New York University] at 03:10 04 May 2015
Key words: dietary pattern, leptin, adiponectin, adults, healthy Objective: Dietary patterns reflect diet and nutritional habits of individuals in a society. Various dietary patterns could influence leptin and adiponectin secretion from adipose tissue. These hormones are associated with metabolic diseases. It is suggested that the leptin-to-adiponectin (L/A) ratio might be a more useful diagnostic marker in predicting chronic diseases than leptin and adiponectin separately. The aim of this study was to investigate the association between various dietary patterns and L/A ratio in Iranian adults. Methods: This cross-sectional study was conducted on 150 apparently healthy subjects aged 25–50 years in Tabriz, Iran. Dietary patterns were determined using 132-item semiquantitative food frequency questionnaire on a 5-point scale. Weight, height, waist circumference (WC), as well as fasting serum leptin and adiponectin levels were measured to assess the association between dietary patterns and L/A ratio. Results: Four major dietary patterns were identified using a factor analysis approach: Western, healthy, mixed, and traditional dietary patterns. Linear regression analysis showed that a Western dietary pattern was negatively associated with serum adiponectin concentration, even after adjusting for the confounders (r D ¡0.19, p D 0.02). No statistically significant associations were found between any dietary pattern and leptin (r D ¡0.14, p D 0.06) or L/A ratio (r D ¡0.10, p D 0.09). Conclusion: Our findings indicate an inverse association between a Western dietary pattern and serum adiponectin levels but not for serum leptin or L/A ratio.
INTRODUCTION
transport to the central nervous system or downergulation of leptin receptors [6]. In addition, concentration of this hormone decreases in hunger and fasting states. Therefore, diet plays a direct and indirect role in the circulatory leptin levels [7]. Adiponectin is another adipocytokine that decreases in obesity, type 2 diabetes, and CVD in contrast to all other adipocytokines. In addition, an increase in serum levels of adiponectin is shown to be associated with insulin sensitivity [8]. These two adipocytokines function oppositely in fat metabolism and incidence of chronic diseases, and various studies have shown that the ratio of leptin to adiponectin (L/A) may be a better indicator of many metabolic diseases than when they are assessed separately [9,10]. In a previous study the adiponectin did not show any correlation with blood pressure, whereas the L/A ratio was correlated to blood pressure and other components of metabolic syndrome [11]. Moreover, this
Obesity is one of the most important public health concerns worldwide. It is associated with a significantly higher prevalence of chronic diseases, including hypertension, diabetes, and cardiovascular diseases (CVDs) [1, 2]. Excessive energy intake leads to accumulation of fat mass and body weight [3]. Adipose tissue, as an endocrine organ, secretes a wide range of adipocytokines such as leptin, adiponectin, visfatin, and tumor necrosis factor-a, which are responsible for majority of the endocrine, metabolic, and vascular disorders related to obesity [4]. Leptin exerts an important role in the regulation of food intake and energy expenditure [5]. Whenever energy intake exceeds the expenditure, adipose tissue increases in mass and leads to obesity. Some obese subjects have high serum leptin levels, suggesting leptin resistance. This condition might be due to decrease in leptin
Address correspondence to: Ali Tarighat-Esfanjani, Nutrition Research Center, School of Nutrition, Tabriz University of Medical Sciences, Attar Nishabouri St., Tabriz 5166614711, I. R. IRAN. E-mail: [email protected]
Journal of the American College of Nutrition, Vol. 34, No. 1, 49–55 (2015) Ó American College of Nutrition Published by Taylor & Francis Group, LLC 49
Downloaded by [New York University] at 03:10 04 May 2015
Dietary Patterns and Leptin-to-Adiponectin Ratio index is more useful than the homeostasis model assessment– estimated insulin resistance in accurate assessment of insulin resistance in subjects without hyperglycemia [12] and patients with diabetes [10]. Indeed, the L/A ratio is considered as an atherosclerotic index in type 2 diabetes [13]. It has been shown that the L/ A ratio is a strong independent predictor of intima media thickness, and it is preferred compared to other adipocytokines [14]. People consume a complex combination of food items that contain a variety of nutrients; thus, recently most nutritional epidemiologic studies have focused on dietary patterns and their associations with the incidence of chronic disease. Simultaneous intake of foods results in a synergistic effect or interaction between them that may influence the absorption and bioavailability of nutrients [15]. Dietary patterns are related with adiponectin and leptin levels. According to these data, there is a positive association between high intakes of whole grains, dietary fiber, and low-fat dairies with levels of adiponectin [16,17]. Moreover, some studies have implied the positive role of a Mediterranean diet [18,19], a dietary pattern high in vegetables, sea foods, soy products, and green tea [20], in elevated levels of serum adiponectin and prevention of CVD. It has been reported that vegetable and dietary fiber intake are negatively associated with serum leptin concentration [21, 22]. Another study did not show any association between dietary patterns and serum leptin levels [23]. To the best of our knowledge, no studies have assessed the association between dietary patterns and L/A ratio. Because the L/A ratio serves as a chronic disease index superior to leptin or adiponectin levels alone, decreased serum adiponectin levels and elevated serum leptin levels are 2 critical biomarkers in prediction of chronic diseases [11], and by considering differences in dietary patterns of various communities we aimed to determine the major dietary patterns of Iranian subjects and their association with the L/A ratio in apparently healthy adults.
MATERIALS AND METHODS Subjects This cross-sectional study is a part of a larger study of 670 apparently healthy subjects that aimed to identify dietary patterns in Tabriz, Iran. These participants were selected based on a number of exclusion criteria, including high physical activity level, pregnancy and lactation, taking any anti-inflammatory medications and drugs that have an effect on body metabolism and weight, or having any evidence of chronic disease such as hypertension, diabetes, CVD, hepatic disorders, renal disease, and cancer. A random subsample consisting of 170 males and females was selected for the present study. Sixteen participants were omitted from the analysis because of missing data. In addition, 4 subjects were excluded due to inadequate blood samples. Therefore, the final sample size of our study was 150 subjects. Weight, height, waist circumference (WC), and fasting serum leptin and adiponectin levels were measured to determine the association between dietary patterns and L/A ratio. This study was approved by the ethics committee of Tabriz University of Medical Science.
Assessment of Dietary Intake Dietary pattern scores were determined by using dietary data from a validated and interviewer-administered 132-item semiquantitative food frequency questionnaire on a 5-point scale. The participants reported their mean frequency of consumption of each food item in a day, week, month, or year and the portion size during the past year. Then mean weekly consumption of food items was calculated. Factor analysis was used to identify the dietary patterns.
Assessment of Leptin and Adiponectin Levels Overnight fasting blood samples were drawn and serum was separated by centrifuging at 3500 rpm for 10–12 minutes. Serum was stored at ¡70 C until analysis. Leptin and adiponectin levels were measured using sandwich enzyme-linked immunosorbent
Table 1. Demographic and Biochemical Characteristics of the Study Populationa
Age (years) Weight (kg) Height (cm) Body mass index (kg/m2) Waist circumference (cm) Adiponectin (ng/ml) Leptinc (ng/ml) L/A ratioc
Total (n D 150)
Male (n D 75)
Female (n D 75)
p Valueb
36.76 (8.87) 71.54 (13.07) 166.48 (9.54) 25.92 (4.83) 87.86 (11.44) 30.63 (8.26) 8.43 (4.25–20.05) 0.29 (0.12–0.66)
37.09 (9.02) 75.58 (12.12) 173.62 (6.51) 25.16 (4.21) 91.27 (11.36) 31.13 (7.94) 6.80 (3.86–13.56) 0.20 (0.11–0.40)
36.43 (8.76) 67.49 (12.80) 159.35 (6.13) 26.68 (5.31) 84.5 (10.56) 30.13 (8.59) 13.42 (4.93–25.44) 0.39 (0.17–0.87)
0.667
Journal of the American College of Nutrition Publication details, including instructions for authors and subscription information: http://www.tandfonline.com/loi/uacn20
Association Between Dietary Patterns and Serum Leptin-to-Adiponectin Ratio in Apparently Healthy Adults a
a
b
Hamed Jafari-Vayghan MS , Ali Tarighat-Esfanjani PhD , Mohammad Asghari Jafarabadi PhD , a
a
a
Mehrangiz Ebrahimi-Mameghani PhD , Sevda Saleh Ghadimi PhD & Zahra Lalezadeh BS a
Nutrition Research Center, School of Nutrition, Tabriz University of Medical Sciences, Tabriz, IRAN b
Tabriz Health Services Management Research Center, School of Health, Tabriz University of Medical Sciences, Tabriz, IRAN Published online: 03 Feb 2015.
Click for updates To cite this article: Hamed Jafari-Vayghan MS, Ali Tarighat-Esfanjani PhD, Mohammad Asghari Jafarabadi PhD, Mehrangiz Ebrahimi-Mameghani PhD, Sevda Saleh Ghadimi PhD & Zahra Lalezadeh BS (2015) Association Between Dietary Patterns and Serum Leptin-to-Adiponectin Ratio in Apparently Healthy Adults, Journal of the American College of Nutrition, 34:1, 49-55, DOI: 10.1080/07315724.2014.880389 To link to this article: http://dx.doi.org/10.1080/07315724.2014.880389
PLEASE SCROLL DOWN FOR ARTICLE Taylor & Francis makes every effort to ensure the accuracy of all the information (the “Content”) contained in the publications on our platform. However, Taylor & Francis, our agents, and our licensors make no representations or warranties whatsoever as to the accuracy, completeness, or suitability for any purpose of the Content. Any opinions and views expressed in this publication are the opinions and views of the authors, and are not the views of or endorsed by Taylor & Francis. The accuracy of the Content should not be relied upon and should be independently verified with primary sources of information. Taylor and Francis shall not be liable for any losses, actions, claims, proceedings, demands, costs, expenses, damages, and other liabilities whatsoever or howsoever caused arising directly or indirectly in connection with, in relation to or arising out of the use of the Content. This article may be used for research, teaching, and private study purposes. Any substantial or systematic reproduction, redistribution, reselling, loan, sub-licensing, systematic supply, or distribution in any form to anyone is expressly forbidden. Terms & Conditions of access and use can be found at http:// www.tandfonline.com/page/terms-and-conditions
Original Research
Association Between Dietary Patterns and Serum Leptin-to-Adiponectin Ratio in Apparently Healthy Adults Hamed Jafari-Vayghan, MS, Ali Tarighat-Esfanjani, PhD, Mohammad Asghari Jafarabadi, PhD, Mehrangiz Ebrahimi-Mameghani, PhD, Sevda Saleh Ghadimi, PhD, Zahra Lalezadeh, BS Nutrition Research Center, School of Nutrition (H.J.-V., A.T.E., M.E.-M., S.S.G., Z.L.), and Tabriz Health Services Management Research Center, School of Health (M.A.J.),Tabriz University of Medical Sciences, Tabriz, IRAN
Downloaded by [New York University] at 03:10 04 May 2015
Key words: dietary pattern, leptin, adiponectin, adults, healthy Objective: Dietary patterns reflect diet and nutritional habits of individuals in a society. Various dietary patterns could influence leptin and adiponectin secretion from adipose tissue. These hormones are associated with metabolic diseases. It is suggested that the leptin-to-adiponectin (L/A) ratio might be a more useful diagnostic marker in predicting chronic diseases than leptin and adiponectin separately. The aim of this study was to investigate the association between various dietary patterns and L/A ratio in Iranian adults. Methods: This cross-sectional study was conducted on 150 apparently healthy subjects aged 25–50 years in Tabriz, Iran. Dietary patterns were determined using 132-item semiquantitative food frequency questionnaire on a 5-point scale. Weight, height, waist circumference (WC), as well as fasting serum leptin and adiponectin levels were measured to assess the association between dietary patterns and L/A ratio. Results: Four major dietary patterns were identified using a factor analysis approach: Western, healthy, mixed, and traditional dietary patterns. Linear regression analysis showed that a Western dietary pattern was negatively associated with serum adiponectin concentration, even after adjusting for the confounders (r D ¡0.19, p D 0.02). No statistically significant associations were found between any dietary pattern and leptin (r D ¡0.14, p D 0.06) or L/A ratio (r D ¡0.10, p D 0.09). Conclusion: Our findings indicate an inverse association between a Western dietary pattern and serum adiponectin levels but not for serum leptin or L/A ratio.
INTRODUCTION
transport to the central nervous system or downergulation of leptin receptors [6]. In addition, concentration of this hormone decreases in hunger and fasting states. Therefore, diet plays a direct and indirect role in the circulatory leptin levels [7]. Adiponectin is another adipocytokine that decreases in obesity, type 2 diabetes, and CVD in contrast to all other adipocytokines. In addition, an increase in serum levels of adiponectin is shown to be associated with insulin sensitivity [8]. These two adipocytokines function oppositely in fat metabolism and incidence of chronic diseases, and various studies have shown that the ratio of leptin to adiponectin (L/A) may be a better indicator of many metabolic diseases than when they are assessed separately [9,10]. In a previous study the adiponectin did not show any correlation with blood pressure, whereas the L/A ratio was correlated to blood pressure and other components of metabolic syndrome [11]. Moreover, this
Obesity is one of the most important public health concerns worldwide. It is associated with a significantly higher prevalence of chronic diseases, including hypertension, diabetes, and cardiovascular diseases (CVDs) [1, 2]. Excessive energy intake leads to accumulation of fat mass and body weight [3]. Adipose tissue, as an endocrine organ, secretes a wide range of adipocytokines such as leptin, adiponectin, visfatin, and tumor necrosis factor-a, which are responsible for majority of the endocrine, metabolic, and vascular disorders related to obesity [4]. Leptin exerts an important role in the regulation of food intake and energy expenditure [5]. Whenever energy intake exceeds the expenditure, adipose tissue increases in mass and leads to obesity. Some obese subjects have high serum leptin levels, suggesting leptin resistance. This condition might be due to decrease in leptin
Address correspondence to: Ali Tarighat-Esfanjani, Nutrition Research Center, School of Nutrition, Tabriz University of Medical Sciences, Attar Nishabouri St., Tabriz 5166614711, I. R. IRAN. E-mail: [email protected]
Journal of the American College of Nutrition, Vol. 34, No. 1, 49–55 (2015) Ó American College of Nutrition Published by Taylor & Francis Group, LLC 49
Downloaded by [New York University] at 03:10 04 May 2015
Dietary Patterns and Leptin-to-Adiponectin Ratio index is more useful than the homeostasis model assessment– estimated insulin resistance in accurate assessment of insulin resistance in subjects without hyperglycemia [12] and patients with diabetes [10]. Indeed, the L/A ratio is considered as an atherosclerotic index in type 2 diabetes [13]. It has been shown that the L/ A ratio is a strong independent predictor of intima media thickness, and it is preferred compared to other adipocytokines [14]. People consume a complex combination of food items that contain a variety of nutrients; thus, recently most nutritional epidemiologic studies have focused on dietary patterns and their associations with the incidence of chronic disease. Simultaneous intake of foods results in a synergistic effect or interaction between them that may influence the absorption and bioavailability of nutrients [15]. Dietary patterns are related with adiponectin and leptin levels. According to these data, there is a positive association between high intakes of whole grains, dietary fiber, and low-fat dairies with levels of adiponectin [16,17]. Moreover, some studies have implied the positive role of a Mediterranean diet [18,19], a dietary pattern high in vegetables, sea foods, soy products, and green tea [20], in elevated levels of serum adiponectin and prevention of CVD. It has been reported that vegetable and dietary fiber intake are negatively associated with serum leptin concentration [21, 22]. Another study did not show any association between dietary patterns and serum leptin levels [23]. To the best of our knowledge, no studies have assessed the association between dietary patterns and L/A ratio. Because the L/A ratio serves as a chronic disease index superior to leptin or adiponectin levels alone, decreased serum adiponectin levels and elevated serum leptin levels are 2 critical biomarkers in prediction of chronic diseases [11], and by considering differences in dietary patterns of various communities we aimed to determine the major dietary patterns of Iranian subjects and their association with the L/A ratio in apparently healthy adults.
MATERIALS AND METHODS Subjects This cross-sectional study is a part of a larger study of 670 apparently healthy subjects that aimed to identify dietary patterns in Tabriz, Iran. These participants were selected based on a number of exclusion criteria, including high physical activity level, pregnancy and lactation, taking any anti-inflammatory medications and drugs that have an effect on body metabolism and weight, or having any evidence of chronic disease such as hypertension, diabetes, CVD, hepatic disorders, renal disease, and cancer. A random subsample consisting of 170 males and females was selected for the present study. Sixteen participants were omitted from the analysis because of missing data. In addition, 4 subjects were excluded due to inadequate blood samples. Therefore, the final sample size of our study was 150 subjects. Weight, height, waist circumference (WC), and fasting serum leptin and adiponectin levels were measured to determine the association between dietary patterns and L/A ratio. This study was approved by the ethics committee of Tabriz University of Medical Science.
Assessment of Dietary Intake Dietary pattern scores were determined by using dietary data from a validated and interviewer-administered 132-item semiquantitative food frequency questionnaire on a 5-point scale. The participants reported their mean frequency of consumption of each food item in a day, week, month, or year and the portion size during the past year. Then mean weekly consumption of food items was calculated. Factor analysis was used to identify the dietary patterns.
Assessment of Leptin and Adiponectin Levels Overnight fasting blood samples were drawn and serum was separated by centrifuging at 3500 rpm for 10–12 minutes. Serum was stored at ¡70 C until analysis. Leptin and adiponectin levels were measured using sandwich enzyme-linked immunosorbent
Table 1. Demographic and Biochemical Characteristics of the Study Populationa
Age (years) Weight (kg) Height (cm) Body mass index (kg/m2) Waist circumference (cm) Adiponectin (ng/ml) Leptinc (ng/ml) L/A ratioc
Total (n D 150)
Male (n D 75)
Female (n D 75)
p Valueb
36.76 (8.87) 71.54 (13.07) 166.48 (9.54) 25.92 (4.83) 87.86 (11.44) 30.63 (8.26) 8.43 (4.25–20.05) 0.29 (0.12–0.66)
37.09 (9.02) 75.58 (12.12) 173.62 (6.51) 25.16 (4.21) 91.27 (11.36) 31.13 (7.94) 6.80 (3.86–13.56) 0.20 (0.11–0.40)
36.43 (8.76) 67.49 (12.80) 159.35 (6.13) 26.68 (5.31) 84.5 (10.56) 30.13 (8.59) 13.42 (4.93–25.44) 0.39 (0.17–0.87)
0.667
