Distribution of Dietary Risk Factors in Iran: National and Sub-National Burden of Disease

Negar Zamaninour, PhD1; Moein Yoosefi, MSc2,3; Mojdeh Soleimanzadehkhayat, MSc4,2; Forough Pazhuheian, MSc2; Sahar Saeedi Moghaddam, MSc2; Shirin Djalalinia, PhD5,2; Nazila Shahbal, BSc2; Rosa Haghshenas, BSc2,6; Mona Marzban, PhD7,2; Arezou DilmaghaniMarand, MSc2; Ameneh Kazemi, MSc6,2; Nasim Hadian, MSc2; Hossein Zokaei, MSc2; Abbas Pariani, MSc8; Mohammad Javad Hajipour, PhD9,2; Shirin Hasani-Ranjbar, MD10; Farshad Farzadfar, MD, MPH, DSC2,6*

disorders. Additionally, protein, omega 3 fatty acids, vitamin D, iodine and selenium in fish all have protective effects on metabolic profiles. 12 On the other hand, it has been well established that trans fatty acids consumed from hydrogenated oil, as well as high salt intake, are associated with cardiovascular diseases. 13,14 Interestingly, previous studies have published reports regarding the sub-optimal dietary intake figures in Iranian adults, 6 although no subnational level data are available. Iran is also facing relatively high rates of diabetes and cardiovascular diseases, [15][16][17][18] which impose direct and indirect health costs on the society. 19,20 Considering SDGs 3.4 (Sustainable Development Goals) "to reduce the unconditional NCDs probability of death by 30% by 2030", 21 scientists, policymakers and managers at national and sub-national levels need data on risk factor distribution. Identifying various food consumption patterns as modifiable risk factors may be imperative in reducing the risk of multiple chronic illnesses and their future costs. For this reason, in the present study, the aim was to investigate the national and sub-national distribution of certain dietary risk factors by age, sex, socio-demographic, socio-economic variables and medical risk factors in Iran.

Materials and Methods
This study was a community population-based, crosssectional survey, and was conducted by the Non-Communicable Diseases Research Center group between April and November 2016, using the modified version of WHO-based STEPS (STEPwise approach to Surveillance) risk factor questionnaire. 22 The target population included adults (male and female) aged 18 and above who lived in urban and rural areas of Iran. It was designed to collect data on 31 050 individuals who were selected through systematic proportional to size cluster random sampling; however, a final total of 30 541 eligible adults were selected to participate in the study (Figure 1). A signed informed consent form was obtained prior to initiation of the study. The study protocol has been previously published 22 and included detailed information on setting, data collection, sampling protocol, and the precise controls used for possible errors such as questioner error, non-response error and error in data entry. 22 The above-mentioned questionnaire measured the daily consumption of fruits, vegetables, milk or dairy products, type of cooking oil, and the frequency of fish and salty processed foods (SPFs) consumed per week. Current tobacco smoking status, household information, and anthropometric and biological measurements were also recorded. The validity and reliability of the questionnaire have been previously evaluated. 22 Selection of Dietary Risk Factors Six dietary risk factors were selected, all of which have demonstrated associations with chronic diseases. Low intake of fruits (<2 servings/day), low intake of vegetables (<3 servings/day), 23,24 low intake of dairy products (<2 servings/day), 25 low intake of fish (<twice/week), 26 high intake of SPF (>0 time/week), 27 and daily intake of HF 28 were considered as nutritional risk factors.
Physical Activity Assessment The Global Physical Activity Questionnaire (GPAQ) was used to assess physical activity levels. 29 The intensity of physical activity was expressed using metabolic equivalents (METs)-minutes per week.

Data Analysis
The distribution of nutritional risk factors in Iran was examined generally by province, sex, age, education level, marital status, wealth index, lipid profiles, and specific NCDs such as diabetes, cardiovascular disease, and hypertension, and was reported as percentage and frequency. Additionally, missing data was controlled for by applying weightings to participants in the responding sample. Data were analyzed using the STATA statistical software version 14.0 (StataCorp. 2015. STATA Statistical Software: Release 14. College Station, TX: StataCorp LP). Survey data analysis was used to analyze the data. Furthermore, the consumption of hydrogenated vegetable oil and margarine was higher in rural populations and among people with lower education levels, lower wealth indices, as well as lower body mass index (BMI<18.5 kg/ m 2 versus ≥ 25 kg/m 2 ). Sub-optimal intake of vegetables (<3 servings/day) was seen in two out of three underweight people. Furthermore, the similarities in the distribution of most of the nutritional risk factors were found in the patient (having diabetes and/or cardiovascular disease and/ or hypertension and/or lipid disorders) and non-patient subgroups. However, the consumption of SPFs was lower in people with cardiovascular diseases and hypertension than in non-patient subgroups.

Distribution of Dietary
It is also worth noting that the frequency and percentage of the missing values of each nutritional risk factor was as follows  Figure 3).

Discussion
The distribution of six dietary risk factors was investigated at the national and sub-national level in Iran. The results at the national level demonstrated that the majority of people in age, sex and BMI specific subgroups had sub-   West Azerbaijan optimal intakes of fruits, vegetables, dairy products, and fish. Overall, 12.8% of all age groups ate SPFs during the week. Additionally, about one in three respondents in the age and sex subgroups used hydrogenated vegetable oil and margarine to cook. Furthermore, in the BMI subgroups, a higher percentage of underweight people (BMI <18.5 kg/m 2 ) had sub-optimal consumption of fruits, vegetables, and dairy products and also used SPFs and HF compared to other BMI subgroups. This may be a reflection of malnutrition in this group of people. Sub-optimal dietary intakes in Iranian adults has been previously reported in recent years. 6,30 Poor dietary quality is driven by a number of factors affecting inadequate food supply (e.g. food and agricultural policies, food marketing), as well as inadequate food utilization (e.g. education, income, nutritional knowledge, access to the supermarket, and food availability in local stores). 31 Previous studies in Iran have highlighted the impact of these factors on inappropriate food intakes. 32,33 As an example, one qualitative study conducted on Iranian men showed that lack of nutritional knowledge, taste preferences for fatty foods and fast food, the influence of friends and peers on youth eating, media advertisements, nutritional transition, women's societal roles, and lack of access to healthy food due to high prices, time limitation, lack of confidence to select healthy foods, and easy access to unhealthy foods were the main obstacles to healthy eating. 32 In turn, factors such as lack of access to healthy food (due to inadequate knowledge, the high cost of healthy foods, time limits for preparing healthy foods, poor restaurant hygiene, and the limited variety of healthy foods), interpersonal and cultural effects (e.g. unhealthy behavioral modeling and inappropriate prioritization), and food preferences (personal taste and the limited variety of healthy foods) have been suggested as the major barriers to healthy nutrition among Iranian females. 33 In spite of the nutritional obstacles mentioned in Iran, there is growing policy attention on increasing fruit and vegetable consumption, limiting salt intake (through mass media education, salt reduction in food industries and restaurants), and reducing fat intake (through public education with an emphasis on reducing fat and oil consumption, as well as encouraging people to use liquid oils in cooking and governmental educational provision about the harmfulness of saturated and trans fatty acids on human health). 34 Despite these efforts, an alarming distribution of nutritional risk factors for NCDs was also shown across the provinces of Iran (based on Table 3). It seems that inequalities arising from the social, political, cultural, economic and geographical conditions in Iran 35,36 could be the main cause of the widespread distribution of nutritional risk factors in certain provinces. Multiple lines of evidence converge to support the potential role of socioeconomic status (SES) in making appropriate food choices. 37,38 Sub-optimal intakes of fruits, vegetables and fish and also consumption of unhealthy fat have been reported among Iranian Kurdish groups with low SES. 39 Similarly, in a study conducted on Kurdish and Azeri ethnic groups in Urmia, Rezazadeh et al showed that household SES was associated with dietary patterns. 40 In addition to SES, belonging to racial and ethnic minority groups has also been considered as a factor affecting diet-related inequalities. 41 As an example, Mexican-American men living in Texas consumed poorer diets (less fruits and vegetables) compared to Latino men in California. 42 Additionally, food insecurity has been reported to be more prevalent in the Iranian Baluch population compared to Fars ethnic households. 43 It is worth noting that food insecurity also affects dietary choices. [44][45][46] Based on a metaanalysis conducted on the prevalence of food insecurity in Iran, 49% of households suffer from food insecurity. 47 Besides these factors, inadequate geographical access to healthy foods is another challenging issue that has been mentioned in previous studies. 48,49 Greater distances to higher quality food stores are also a major obstacle to accessing healthy foods, especially in low-income areas. 50,51 On the whole, the current study was a step toward understanding the distribution of some dietary risk factors in order to provide a basis for future studies into the deeper causes of these distributions.
The strength of this study was that the distribution of major nutritional risk factors was investigated at both national and sub-national levels. However, the current study had some limitations, as follows. Firstly, the study was designed to provide general information about nutritional risk factors at national and sub-national levels in Iran, without measuring total energy or fat intake. Secondly, the contribution of nutritional risk factors to the national burden of disease has not been investigated. Thirdly, some important dietary risk factors, such as low intake of whole grains, seafood omega-3 fatty acids, nuts, and seeds, and high intake of processed meat and sugarsweetened beverages, were not included in this study.
In conclusion, there is a large gap between the recommendation and consumption of fruits, vegetables, dairy products, fish, SPFs, and sources rich in transfatty acids (hydrogenated vegetable oil and margarine) among the adult population of Iran. Several individual-, community-and national-level factors can explain this gap, which should be considered as a priority for politicians to prevent NCDs.