Dietary intake and rural-urban migration in India: a cross-sectional study

Effectiveness of a school-based behavioural change intervention in reducing chronic disease risk factors in Chandigarh, India: a cluster-randomised controlled trial

Background

Early behavioural risk factors such as unbalanced diets, physical inactivity and tobacco and alcohol consumption lead to chronic diseases in later life. We conducted a cluster-randomised controlled trial to measure the effect of a school-based health-promotion intervention in reducing the behavioural risk factors of chronic diseases.

Methods

Twelve public schools in the Chandigarh, India were randomised to the intervention and control arm. Adolescents studying in eighth grade (n = 453), their parents (n = 395) and teachers (n = 94) were recruited for the current study. The Precede-Proceed Model was followed for intervention development. Intervention in each cluster comprised of one classroom session, four physical activity (PA) sessions every week for adolescents and four separate sessions for parents and teachers. Primary outcomes were eight binary or continuous measures of behavioural risk factors among adolescents (n = 359). Physical Activity Questionnaire-Adolescents (PAQ-A) scores were used to estimate physical activity. The ANCOVA based on cluster proportions or means was used to estimate the intervention effect accounting for baseline data.

Findings

Among adolescents, the intervention reduced salt intake by 0.5 g/d (95% CI: -0.9, -0.1), proportion of current alcohol users by 5% (95% CI: -9, -0.007), and increased fruit consumption by 18 g/d (95% CI: 5, 30) and PA by 0.2 PAQ-A score (95% CI: 0.07, 0.3). However, the intervention had no effect on the sugar and vegetable intake and on smokers and tobacco chewers. Exploratory analysis revealed that among parents, PA increased by 205 metabolic equivalents task (MET) units (95% CI: 74.5, 336), fruits intake by 20 g/d (95% CI: 6, 34), and vegetable intake by 117 g/d (95% CI: 50.5, 183). Whereas salt consumption decreased by 0.5 g/d (95% CI: 0.15, 0.9) and the proportion of current alcohol users declined by 5% (95% CI: 9, -1) among parents. Vegetable consumption increased by 149 g/d (95% CI: 12, 286) among teachers.

Interpretation

The intervention package implemented among adolescents by involving parents and teachers is an effective model for school-based behaviour-change interventions.

Funding

MK received partial funding from the George Institute for Global Health, Hyderabad, India for the salt-reduction component of the study.

Dietary patterns and their socio-demographic correlates in the context of migration and urbanisation demonstrate nutrition transitions in South Africa

This paper investigates the demographic and socio-economic correlates of dietary patterns in South Africa, drawing on a sample of young adults experiencing internal migration and urbanisation. We use data from the 2018 baseline survey of the Migrant Health Follow-Up Study, an original longitudinal cohort study consisting of 3,087 internal migrants and rural residents aged 18-40 nested within the Agincourt Health and socio-Demographic Surveillance System in rural northeast South Africa. We employ principal components analysis to identify dietary patterns from food frequency questionnaires and ordinary least squares regression to assess whether migration and other socio-economic characteristics correlate with specific dietary patterns at baseline. We observe five distinct dietary patterns characterised by frequent consumption of processed foods, red meat, fruits and vegetables, diverse foods, and high sugar/fat foods. We find migration to be significantly associated with more frequent consumption of both processed foods and fruits and vegetables; we also find the association between migration status and dietary patterns to be heterogenous depending on migrants' destinations. This paper extends current understanding of changing dietary patterns in the context of nutrition transitions with attention to dynamic migration processes rather than static rural-urban differences.

Heterogeneity of Dietary practices in India: current status and implications for the prevention and control of type 2 diabetes

Diet is one of the important modifiable factors in prevention of type 2 diabetes (T2D), making it important to understand geographical variations of food consumption pattern, their similarities and differences across various regions. Asian Indian diet patterns are mostly carbohydrate-based and with vast regional diversity. Staple food, food groups consumed, meat consumption pattern, type of fermented foods, food preparations, type of cooking oil used and food ingredients vary with different regions of India. There has been a slow transition from consumption of coarse grains to refined grains owing to socio-economic, cultural and other factors. Consumption of fruits and vegetables, fats, ready-to-eat foods and sugar is higher in urban population whereas consumption of carbohydrates in the form of cereals and millets is higher among the rural population. Cereal grains followed by pulses and legumes are main sources of protein, given that the frequency of meat consumption is low even among non-vegetarians in India compared to other countries. Overall, there is a tendency towards consumption of calorie-dense foods at the cost of food diversity, which may also result in micronutrient deficiencies as well as development of T2D and related metabolic diseases. Public health strategies and policy level decisions involving stakeholders with diet and lifestyle modification as focal points are absolute priorities to prevent and manage the burden of obesity and T2D in India.

Lifestyle risk factors and metabolic markers of cardiovascular diseases in Bangladeshi rural-to-urban male migrants compared with their non-migrant siblings: A sibling-pair comparative study

Background

The increasing prevalence of cardiovascular diseases (CVDs) in developing countries like Bangladesh has been linked to progressive urbanisation. Comparisons of rural and urban populations often find a higher prevalence of CVD risk factors in the urban population, but rural-to-urban migrants might have different CVD risk profiles than either rural or urban residents. This study aimed to describe differences in CVD risk factors between migrants and non-migrants siblings and to determine whether acculturation factors were associated with CVD risk factors among migrants.

Methods

Using a sibling-pair comparative study, 164 male migrant who migrated from Pirganj rural areas to Dhaka City and their rural siblings (total N = 328) were assessed by interview, anthropometric measurement, blood pressure and blood samples. Comparisons were made using linear or logistic mixed effects models.

Findings

Physical inactivity, inadequate intake of fruit and vegetables and possible existence of a mental health disorder had 3.3 (1.73; 6.16), 4.3 (2.32; 7.92) and 2.9 (1.37; 6.27) times higher odds among migrants than their rural siblings, respectively. Migrants watched television on average 20 minutes (95% CI 6.17–35.08 min/day) more per day than the rural sibling group whereas PUFA intake, fruit and vegetable and fish intake of the migrants were -5.3 gm/day (-6.91; -3.70), -21.6 serving/week (-28.20; -15.09), -14.1 serving/week (-18.32; -9.87), respectively, lower than that of the rural siblings. No significant difference was observed for other variables. After adjusting, the risk of physical inactivity, inadequate fruit and vegetable intake, a mental health disorder and low HDL were significantly higher in migrants than in rural siblings and tended to be higher for each increasing tertile of urban life exposure.

Conclusion

The findings suggest that migration from rural-to-urban environment increases CVD risk which exacerbate with time spent in urban area due to acculturation. This study gives new insights into the increased CVD risk related with migration and urbanization in Bangladesh.

Urban-rural disparities in blood pressure and lifestyle risk factors of hypertension among Indian individuals

Objectives

This study aims to assess the urban-rural difference in prevalence of hypertension (HT) and to explore the disparities in lifestyle risk factors of HT among urban and rural individuals aged 15-49 years in India.

Study Design

The cross-sectional data collected as a part of the fourth round of National Family Health Survey (NFHS-4) was analysed in this observational study. NFHS-4 was conducted between January 2015 and December 2016 amongst men aged 15-54 years and women aged 15-49 years. In order to maintain uniformity, age group of 15-49 years was considered. Descriptive analyses were performed for sociodemographic and lifestyle factors. Binary logistic regression was conducted to assess the predictors of HT in men and women in urban and rural settings. The presence of HT was considered as the outcome variable.

Results

The overall age adjusted prevalence of HT was 17.2% and was greater in urban (18.3%) than in rural population (15.5%). The age adjusted prevalence was also higher in males (18.2%) as compared to females (16.1%). Age and wealth were associated with HT in both urban and rural population. Education and dietary habits played a role in all except rural men. Alcohol consumption, diabetic status and marital status were significantly associated with HT in both urban and rural women. Occupation was associated with HT only in urban women.

Conclusions

The study has shown higher HT prevalence in urban areas despite higher prevalence of lifestyle risk factors in rural settings. This calls for more robust screening and health education in the entire population, especially in rural areas.

The role of dairy in healthy and sustainable food systems: community voices from India

BACKGROUND

Managing the role of dairy foods in healthy and sustainable food systems is challenging. Milk production is associated with greenhouse gas emissions and milk-based processed foods can be high in fat, sugar and salt; yet, milk production provides income generating opportunities for farmers and dairy foods provide essential nutrients to young children, with a cultural significance in many communities. This is particularly relevant to India, the world's largest producer of milk. The aim of this study was to use Photovoice, a participatory research method, to explore the experiences and perceptions of communities in India on the role of dairy products in local sustainable and healthy food systems.

METHODS

Purposive sampling recruited two women's self-help groups in Visakhapatnam, Andhra Pradesh: one in a rural area and one in an urban area. A total of 31 participants (10-17 urban group and 12-14 rural group), produced photographs with captions to represent their views on how dairy was produced, sold, and consumed in their community. A discussion workshop was held in each area, with prompts to consider health and the environment. Workshop transcripts, photographs and captions were analysed qualitatively using thematic analysis.

RESULTS

A range of experiences and perceptions were discussed by the two women's self help groups. Participants had an awareness of their local food system and how stages of dairy food supply chains were non-linear and inherently interconnected. Three main themes were identified: 1) Quality and value matters to producers and consumers; 2) The need to adapt to sustain dairy farmer livelihoods in water scarce areas; 3) It's not only about health.

CONCLUSIONS

Moderate milk-producing states such as Andhra Pradesh will continue to develop their dairy industry through policy actions. Including communities in policy discussions through innovative methods like Photovoice can help to maximise the positive and minimise the negative role of dairy in evolving local food systems.

Nutrition-related knowledge, practice, and weight status of patients with chronic diseases attending a district hospital in Nigeria

Background:

Aim:

Methods:

Results:

Conclusion:

Effect of internal migration on diabetes and metabolic abnormalities in India - The ICMR-INDIAB study

AIMS

To assess the effect of migration (rural-to-urban and vice versa) on prevalence of diabetes and metabolic disorders in Asian Indians participating in the Indian Council of Medical Research-India Diabetes (ICMR-INDIAB) study.

MATERIALS AND METHODS

The ICMR-INDIAB study is a national study on diabetes and associated cardiometabolic disorders in individuals aged ≥20 years from 28 states and 2 union territories of India. Individuals who moved to a different place from their place of birth and had resided in the new location for at least one year were considered as migrants. Anthropometric measurements, blood pressure estimation and a capillary oral glucose tolerance test were performed.

RESULTS

Of the 113,043 participants, 66.4% were non-migrant rural dwellers, 19.4% non-migrant urban dwellers, 8.4% rural-urban migrants, 3.8% multiple migrants and 2.0% urban-rural migrants. Weighted prevalence of diabetes was highest in rural-urban migrants followed by urban dwellers, urban-rural migrants and rural dwellers [14.7%, 13.2%, 12.7% and 7.7% respectively (p < 0.001)]. Rural-urban migrants had highest prevalence of abdominal obesity (50.5%) compared to the other three groups. The risk for diabetes was 1.9 times higher in rural-urban migrants than among rural dwellers. Five risk factors [hypertension, abdominal and generalized obesity, physical inactivity and low fruit and vegetable intake] together explained 69.8% (partial population attributable risk) of diabetes among rural-urban migrants and 66.4% among non-migrant urban dwellers.

CONCLUSIONS

Rural-to-urban migration is associated with increased risk of developing diabetes and other cardiometabolic abnormalities. Adoption of healthier lifestyle patterns among migrants could help prevent/delay onset of these abnormalities in this population.

Sociodemographic correlates of abnormal blood profile in tribal districts of Eastern India

Objective

To assess the correlates of sociodemographic profile with abnormal blood profile in tribal districts of Odisha.

Design

This was a cross-sectional study. The abnormal blood profile cut-offs were: Random blood sugar >200 mg/dl, Triglycerides >150 mg/dl, and Cholesterol >200 mg/dl.

Setting

The study was carried out in Daringbadi and Tangi (Choudwar) blocks from Kandhamal and Cuttack district, respectively, in the eastern state of Odisha in India.

Participants

Data of 2,000 households selected consecutively from 30 villages was collected for persons aged more than 6 years from either block on sociodemographic aspects and food consumption by households. Anthropometric measurements were taken for persons aged 11 years and above. Approximately 10%, that is, 400 households were chosen for blood sample collection for estimation of random blood sugar (RBS) and lipid profile [Serum Triglycerides (TG) and cholesterol] in persons aged 11 years and above.

Results

The blood reports revealed that out of the total samples collected, 9.2% had elevated RBS, 20.8% had elevated TG, and 8.8% had elevated cholesterol levels overall. The prevalence of elevated RBS, TG, and Cholesterol was 2.3%, 15%, and 5.3%, respectively, in Daringbadi, while in Tangi-Choudwar the elevated markers were 17%, 27.2%, and 12.8% for RBS, TG, and Cholesterol, respectively. Our study found that compared to the Daringbadi block, a significantly higher (P < 0.05) proportion of people from the Tangi-Choudwar block suffered from hyperglycemia (OR = 0.11; 95% CI: 0.06, 0.20), hypertriglyceridemia (OR = 0.47; 95% CI: 0.34, 0.64), and hypercholesterolemia (OR = 0.38; 95% CI: 0.24, 0.59). Hence, it was observed that the population of Daringbadi was 89%, 53%, and 62% less likely to have elevated random blood sugar level, serum triglycerides, and serum cholesterol, respectively, than the population of Tangi-Choudwar block. Overall, the population of Tangi-Choudwar was found to be more predisposed to an abnormal blood profile which might be indicate a less healthy lifestyle and diet in this block as compared to Daringbadi block.

Conclusions

This study found that the sociodemographic factors influencing lifestyle and diet patterns of a population have an impact on the health of a population. We found that the tribal block which was more developed and had more intake of junk food and sedentary lifestyle similar to urban areas also had a greater proportion of population with an abnormal blood profile as compared to the less-developed tribal block. Hence, health promotion for a healthy lifestyle and diet is needed as a part of national health policy to implement primordial prevention and to prevent the emergence of risk factors from an early age. The frontline health workers and family physicians can play an important role in promoting a healthy lifestyle.

CYP2C19 & UGT1A6 genetic polymorphisms and the impact on Valproic acid-induced weight gain in people with epilepsy: Prospective genetic association study

OBJECTIVES

To study the association between CYP2C19*2 (681 G > A) and UGT1A6*2 (552A > C) polymorphisms on Valproic acid (VPA)-induced weight gain in People with epilepsy (PWE).

METHODS

We recruited PWE on VPA monotherapy and genotyped for CYP2C19 and UGT1A6 polymorphisms. Association between CYP2C19 polymorphism and weight gain was the primary outcome parameter. We followed them up monthly for six months and recorded Body mass index (BMI), drug compliance, side effects, food frequency, physical activity.

RESULTS

Of 108 participants recruited, we assessed the association between the polymorphism and weight gain in 101 PWE for CYP2C19*2 and 103 PWE for UGT1A6*2 polymorphism. The proportion of participants with weight gain was higher in those with poor and intermediate metabolizer genotypes of CYP2C19 (*1/*2 and *2/*2) compared to extensive metabolizers (*1/*1) [53.3 % vs 31.7 %, RR 1.68, 95 % CI (1.01-2.79), P = 0.03]. However, CYP2C19*2 allele did not show an increased risk of weight gain over the CYP2C19*1 allele. No association could be demonstrated with UGT1A6 genotypes and weight gain. In logistic regression analysis, CYP2C19*2 carrier genotype was the independent predictor of weight gain. OR 2.89 [95% CI (1.07-7.84)]. There were no significant association with serum TSH, fT4, testosterone, and valproate levels with CYP2C19 or UGT1A6 polymorphisms.

SIGNIFICANCE

People with epilepsy carrying CYP2C19 polymorphisms (*1/*2) and (*2/*2) had 3 times higher risk of VPA-induced weight gain compared to wild type (*1/*1).

Urban-rural differences in the association between long-term exposure to ambient air pollution and obesity in China

INTRODUCTION

Ambient air pollution might increase the risk of obesity; however, the evidence regarding the relationship between air pollution and obesity in comparable urban and rural areas is limited. Therefore, our aim was to contrast the effect estimates of varying air pollution particulate matter on obesity between urban and rural areas.

METHODS

Four obesity indicators were evaluated in this study, namely, body mass index (BMI), waist circumference (WC), waist-to-hip ratio (WHR), and waist-to-height ratio (WHtR). Exposure to ambient air pollution (e.g., particulate matter with aerodynamic diameters 1.0 μm [PM₁], PM_2.5, and PM₁₀) was estimated using satellite-based random forest models. Linear regression and logistic regression models were used to assess the associations between air pollution particulate matter and obesity. Furthermore, the effect estimates of different air pollution particulates were contrasted between urban and rural areas.

RESULTS

A total of 36,998 participants in urban areas and 31, 256 in rural areas were included. We found positive associations between long-term exposure to PM₁, PM_2.5, and PM₁₀ and obesity. Of these air pollutants, PM_2.5 had the strongest association. The results showed that the odds ratios (ORs) for general obesity were 1.8 (95% CI, 1.64 to 1.98) per interquartile range (IQR) μg/m³ increase in PM₁, 1.89 (95% CI, 1.71 to 2.1) per IQR μg/m³ increase in PM_2.5, and 1.74 (95% CI, 1.58 to 1.9) per IQR μg/m³ increase in PM₁₀. The concentrations of air pollutants were lower in rural areas, but the effects of air pollution on obesity of rural residents were higher than those of urban residents.

CONCLUSION

Long-term (3 years average) exposure to ambient air pollution was associated with an increased risk of obesity. We observed regional disparities in the effects of particulate matter exposure from air pollution on the risk of obesity, with higher effect estimates found in rural areas. Air quality interventions should be prioritized not only in urban areas but also in rural areas to reduce the risk of obesity.

Association between duration of residence and prevalence of type 2 diabetes among male South Asian expatriate workers in the United Arab Emirates: a cross-sectional study

Expatriates account for about 80% of the total population in the United Arab Emirates (UAE). This study aimed to evaluate the hypothesis that prevalence of type 2 diabetes in male South Asian expatriates increases with increased length of residence in the UAE.

DESIGN, SETTINGS AND PARTICIPANTS

This cross-sectional study recruited a representative sample (n=1375) of male South Asian expatriates aged ≥18 years in Al Ain, UAE. Sociodemographic, anthropometric and lifestyle data were obtained using a pilot-tested adapted version of the WHO STEPS instrument.

MAIN OUTCOME MEASURES

Duration of residence was used as a marker for acculturation. Type 2 diabetes was defined as a self-reported physician diagnosis of diabetes or a glycosylated haemoglobin blood level ≥6.5%.

RESULTS

Mean (±SD) age of participants was 34.0±9.9 years. Overall, the prevalence of type 2 diabetes was 8.3% (95% CI 6.8% to 9.8%). Diabetes prevalence was positively associated with longer duration of residence in the UAE, 2.7%, <5 years; 8.2%, 5-10 years; and 18.8%, >10 years. After adjusting for age, nationality, and income and age, expatriates were more likely to develop diabetes if residing in the UAE for 5-10 years (OR=2.18; 95% CI 1.02 to 4.67) or >10 years (OR=3.23; 95% CI 1.52 to 6.85) compared with those residing for <5 years.

CONCLUSIONS

After controlling for potential confounding factors, longer duration of residence was significantly associated with a higher prevalence of type 2 diabetes in male South Asian expatriate workers in the UAE.

Is night-time light intensity associated with cardiovascular disease risk factors among adults in early-stage urbanisation in South India? A cross-sectional study of the Andhra Pradesh Children and Parents Study

OBJECTIVES

To explore associations of night-time light intensity (NTLI), a novel proxy for continuous urbanisation levels, with mean systolic blood pressure (SBP), body mass index (BMI), fasting serum low-density lipoprotein (LDL) and fasting plasma glucose (FPG), among adults in early-stage urbanisation in Telangana, South India.

DESIGN

Cross-sectional analysis of the third wave of the Andhra Pradesh Children and Parents Study cohort.

SETTING

28 villages representing a continuum of urbanisation levels, ranging from rural settlement to medium-sized town in Telangana, South India.

PARTICIPANTS

Data were available from 6944 participants, 6236 of whom were eligible after excluding pregnant women, participants younger than 18 years of age and participants missing data for age. Participants were excluded if they did not provide fasting blood samples, had implausible or missing outcome values, were medicated for hypertension or diabetes or had triglyceride levels invalidating derived LDL. The analysis included 5924 participants for BMI, 5752 participants for SBP, 5287 participants for LDL and 5328 participants for FPG.

RESULTS

Increasing NTLI was positively associated with mean BMI, SBP and LDL but not FPG. Adjusted mean differences across the range of village-level NTLI were 1.0 kg/m2 (95% CI 0.01 to 1.9) for BMI; 4.2 mm Hg (95% CI 1.0 to 7.4) for SBP; 0.3 mmol/L (95% CI -0.01 to 0.7) for LDL; and -0.01 mmol/L (95% CI -0.4 to 0.4) for FPG. Associations of NTLI with BMI and SBP were stronger in older age groups.

CONCLUSION

The association of NTLI with cardiovascular disease (CVD) risk factors identify NTLI as a potentially important tool for exploring urbanisation-related health. Consistent associations of moderate increases in urbanisation levels with important CVD risk factors warrant prevention strategies to curb expected large public health impacts from continued and rapid urbanisation in India.

Protocol for a case-control study of vitamin D status, adult multidrug-resistant tuberculosis disease and tuberculosis infection in Mumbai, India

INTRODUCTION

Vitamin D status may be an important determinant of multidrug-resistant tuberculosis (MDR-TB) infection, progression to disease and treatment outcomes. Novel and potentially cost-effective therapies such as vitamin D supplementation are needed to stem the tide of TB and MDR-TB globally, particularly in India, a country that accounts for the largest fraction of the world's TB incidence and MDR-TB incidence, and where vitamin D deficiency is endemic. While vitamin D has shown some promise in the treatment of MDR-TB, its role in the context of MDR-TB infection and progression to disease is largely unknown.

METHODS AND ANALYSIS

Through a case-control study in Mumbai, India, we aim to examine associations between vitamin D status and active MDR-TB and to investigate vitamin D status and TB infection among controls. Cases are adult outpatient pulmonary patients with MDR-TB recruited from two public TB clinics. Controls are recruited from the cases' household contacts and from non-respiratory departments of the facilities where cases were recruited. Cases and controls are assessed for serum 25-hydroxyvitamin D concentration, nutrient intake, diet quality, anthropometry and other relevant clinical and sociodemographic parameters. Controls undergo additional clinical assessments to rule out active TB and laboratory assessments to determine presence of TB infection. Statistical analysis investigates associations between vitamin D status and active MDR-TB and between vitamin D status and TB infection among controls, accounting for potential confounding effects of diet, anthropometry and other covariates.

ETHICS AND DISSEMINATION

This study has been approved by Harvard T.H. Chan School of Public Health Institutional Review Board; Foundation for Medical Research Institutional Research Ethics Committee and Health Ministry's Screening Committee of the Indian Council for Medical Research. Permission was granted by the Municipal Corporation of Greater Mumbai, India, a collaborating partner on this research. Outcomes will be disseminated through publication and scientific presentation.

TRIAL REGISTRATION NUMBER

NCT04342598.

Urbanization and food consumption in India

The shift towards urban living is changing food demand. Past studies on India show significant urban–rural differences in food consumption. However, a scientific understanding of the underlying relationships between urbanization and food consumption is limited. This study provides the first detailed analysis of how urbanization influences both quantity and diversity of food consumption in India by harnessing the strength of multiple datasets, including consumer expenditure surveys, satellite imagery, and census data. Our statistical analysis shows three main findings. First, in contrast to existing studies, we find that much of the variation in food consumption quantity is due to income and not urbanization. After controlling for income and state-level differences, our results show that average consumption is higher in urban than rural areas for fewer than 10% of all commodities. That is, there is nearly no difference in average consumption between urban and rural residents. Second, we find the influence of urbanization as a population share on food consumption diversity to be statistically insignificant (p-value > 0.1). Instead, the results show that infrastructure, market access, percentage working women in urban areas, and norms and institutions have a statistically significant influence. Third, all covariates of food consumption diversity we tested were found to be associated with urbanization. This suggests that urbanization influences on food consumption are both indirect and multidimensional. These results show that increases in the urban population size alone do not explain changes in food consumption in India. If we are to understand how food consumption may change in the future due to urbanization, the study points to the need for a more complex and multidimensional understanding of the urbanization process that goes beyond demographic shifts.

India has natural resource capacity to achieve nutrition security, reduce health risks and improve environmental sustainability

Sustainable development of India's food system must ensure a growing population is fed while minimizing both widespread malnutrition and the environmental impacts of food production. After assessing current adequacy of nutrient supplies at the national level, associated natural resource use (land, fresh water) and greenhouse gas (GHG) emissions, we apply an integrated subnational environmental and nutritional optimization approach to explore resource constraints that might limit the achievement of national food self-sufficiency goals. We find that India currently has the capacity to produce sufficient amounts of nutritious foods, supplying vitamins and minerals that would mostly exceed requirements. Regional cropland use could be reduced by up to 50%, water demand by up to 65% and combined resource inputs by up to 40% while still supporting adequate nutrition. Associated GHG emissions would decline by 26-34% and could possibly be sequestered in agroforestry systems. Such dietary shifts could lower the number of diet-related premature deaths by 14-30%. Achieving these potential gains, however, would require a major transition from current production and consumption patterns, particularly of refined cereals, to free-up resources for more traditional and nutritious foods.

Association between age at arrival, duration of migration, and overweight/obesity in Chinese rural-to-urban migrants: the Yi migrant study

Background:

Urbanization in China is rapidly proceeding, but rural-to-urban migration and its association with overweight and obesity is not well studied. This study aimed to explore the age at arrival, duration of migration, and the corresponding association with overweight/obesity in Yi migrants in China.

Methods:

A cross-sectional study was conducted in rural and urban areas in 2015 in Sichuan province, China. Demographic characteristics, lifestyle factors, and anthropometry were collected. General linear regression models were used to assess the effect of duration of migration (1–10, 11–20, 21–30, and >30 years) on body mass index (BMI). Multi-variable logistic regression was used to examine the association between duration of migration and overweight/obesity (BMI ≥ 25 kg/m²).

Results:

A total of 3056 Yi people (1894 Yi farmers and 1162 Yi migrants) aged 20 to 80 years were enrolled. After adjusting for age, sex, and other potential confounders, Yi migrants had 1.71 kg/m² (95% confidence interval [CI]: 1.36–2.06) higher BMI and a 2.13-fold (95% CI: 1.71–2.65) higher risk of overweight/obesity than Yi farmers. In Yi migrants, stratified by age at arrival, no significant association between duration of migration and overweight/obesity was observed in those who were 0 to 20 years old at arrival. In comparison, in migrants >20 years old at arrival, compared with the reference group (1–10 years), long-term migration (>30 years) was found to be associated with overweight/obesity after adjustment (odds ratio: 1.85, 95% CI: 1.04–3.29).

Conclusions:

Yi migrants were observed to have greater risk of overweight/obesity than Yi farmers. In Yi migrants, the risk of overweight/obesity increased according to the duration of migration, especially in those who were older upon their arrival.

The relationship between lifestyle components and dietary patterns

We conducted a narrative review on the interaction between dietary patterns with demographic and lifestyle variables in relation to health status assessment. The food pattern has the advantage of taking into account the correlations that may exist between foods or groups of foods, but also between nutrients. It is an alternative and complementary approach in analysing the relationship between nutrition and the risk of chronic diseases. For the determination of dietary patterns one can use indices/scores that evaluate the conformity of the diet with the nutrition guidelines or the established patterns (a priori approach). The methods more commonly used are based on exploratory data (a posteriori): cluster analysis and factor analysis. Dietary patterns may vary according to sex, socio-economic status, ethnicity, culture and other factors, but more, they may vary depending on different associations between these factors. The dietary pattern exerts its effects on health in a synergistic way or even in conjunction with other lifestyle factors, and we can therefore refer to a 'pattern of lifestyle'.

Prevalence and regional variations of coexistence of child stunting and maternal overweight or obesity in Myanmar

OBJECTIVE

The current study aimed to investigate double burden of malnutrition within households at the national and subnational levels and to identify its association with sociodemographic factors in Myanmar.

DESIGN

All the variables were extracted from children's file of the Myanmar Demographic and Health Survey 2015-2016. Children under five were identified as stunted based on a height-for-age < -2 sd below the WHO reference median. Maternal overweight/obesity was defined as a BMI ≥ 23 kg/m2. A stunted child with an overweight/obese mother (SCOM) was classified as a double-burden household.

SETTING

A national household survey in Myanmar.

PARTICIPANTS

Children under five and their mothers (n 3954 pairs).

RESULTS

Mean ages of children and mothers were 29 (se 0·14) months and 30·9 (se 0·32) years, respectively. National prevalence of childhood stunting and maternal overweight/obesity was 28·0 % and 39·4 %, respectively, and the prevalence of SCOM was 9·1 %. Significant regional differences were found in SCOM, ranging from 3·6 % in Naypyitaw to 12 % in Kachin and Mon and 14·6 % in Kayah. In the multinomial logistic regression analysis, relative to neither a stunted child nor an overweight/obese mother, child's age, maternal age, maternal experience of a teen birth, short mothers, mothers with primary education and in middle or rich wealth tertiles, and some regions (Kachin, Kayah, Shan, Sagaing, Taninthayi, Ayeyarwaddy, Mon and Yangon) were associated with greater odds of SCOM.

CONCLUSIONS

The current study showed a relatively high national prevalence of SCOM and significant regional variations. Overarching policies and programmes with culturally sensitive strategies need to be formulated and implemented.

Meat, fruit, and vegetable consumption in sub-Saharan Africa: a systematic review and meta-regression analysis

CONTEXT

The dietary choices people make affect personal health and have consequences for the environment, both of which have serious implications for the 2030 Sustainable Development Agenda. In global reviews, the literature on meat, fruit, and vegetable consumption in sub-Saharan Africa (SSA) is limited.

OBJECTIVE

This systematic review set out to quantify meat, fruit, and vegetable consumption in SSA populations and to answer the following question: How much meat, fruit, and/or vegetables are being consumed daily by which individuals in SSA over the years?

DATA SOURCES

Following the PRISMA guidelines, the authors systematically searched the MEDLINE, EMBASE, ASSIA CINAHL, Web of Science, POPLINE, and Google Scholar databases to identify 47 (out of 5922 search results) studies reporting meat, fruit, and/or vegetable consumption in SSA populations.

DATA EXTRACTION

Three independent investigators extracted data on year of data collection, study country, study population and geographical context, and population intake of meat, fruit, and/or vegetables.

DATA ANALYSIS

Using STATA SE version 15 software, random-effects meta-regression analyses were used to test the effect of year of data collection and method of data collection on population meat, fruit, and vegetable consumption. The analyses also tested any association between age, sex, rural/urban residence, or a country's economic development and population intake of meat, fruits, and/or vegetables. The review was started in 2017 and completed in 2019.

RESULTS

Richer SSA countries were likely to consume more meat (ß = 36.76, P = 0.04) and vegetables (ß =43.49, P  = 0.00) than poorer countries. Vegetable intake has increased dramatically over the last 3 decades from ≈10 g to ≈110 g (ß = 4.43, P  = 0.00). Vegetable (ß= -25.48, P  = 0.00) consumption was higher in rural than in urban residents. Although the trend of meat consumption has risen (≈25 g to ≈75 g), the trend is nonsignificant (ß = 0.63, N.S.). Daily average per capita meat consumption was 98 g - above the 70 g recommendation - while fruit and vegetable intake (268 g) remain below the World Health Organization's recommendation (400 g).

CONCLUSIONS

Given the low intake of plant-based foods, it is likely that SSA populations may be deficient in high-quality protein and micronutrients as suggested by the EAT-Lancet Commission. There is a need to promote both an adequate supply and demand of plant-based protein and micronutrients, including fruit, vegetables, nuts, seeds, and legumes, in SSA countries. While dietary changes in SSA may offer large absolute benefits, consideration of the magnitude of dietary change, particularly increasing or reducing meat consumption, will need to occur in a way that ensures that policy and interventions support the reduction of undernutrition and micronutrient deficiencies without worsening the prevalence and environmental impacts of noncommunicable diseases. There is also the need for preventive action that ensures that SSA populations do not increase their meat consumption as disposable incomes increase and countries' economic development rises, as is seen in most countries undergoing economic transformation.

SYSTEMATIC REVIEW REGISTRATION

PROSPERO registration no. CRD42018090497.

Longitudinal Association between Urbanicity and Total Dietary Fat Intake in Adults in Urbanizing China from 1991 to 2015: Findings from the CHNS

Few studies have examined the longitudinal association between urbanicity and dietary fat intake in Chinese adults. A population-based longitudinal observational study was carried out in Chinese adults aged 18–65 from the China Health and Nutrition Survey. Three consecutive 24 h dietary recalls were used to assess dietary fat intake. Multilevel models were used to explore the relationship between urbanicity and dietary fat intake. People in the highest urbanicity quartile had the increments of 7.48 g/d (95% CI:5.42–9.58) and 8.92 g/d (95% CI: 7.03–10.80) in dietary fat intake, 2.86 (95% CI: 2.29–3.44) and 2.69 (95% CI: 2.13–3.25) in proportion of energy from total fat, and odds ratios (ORs) for the risk of excess dietary fat intake of 1.84 (95% CI: 1.65–2.05) and 2.01 (95% CI: 1.78–2.26) for men and women, respectively, compared to the lowest quartile after controlling for potential confounders. These results indicate that urbanicity was an important factor influencing dietary fat intake among Chinese adults. Aggressive nutritional education action coupled with governmental guidelines and programs tailored for the Chinese population are required to promote less dietary fat intake, especially in those adults living in less urbanized areas and whose dietary fat intake is ≥ 30% of their total energy intake per day.

Cardiometabolic risk profile and diet quality among internal migrants in Brazil: a population-based study

PURPOSE

Studies of migrants can improve understanding of the environmental influence on the risk of chronic diseases. In continental countries, internal migration has been associated with changes in diet and health status. The objective of this study is to assess differences in diet quality and the cardiometabolic risk profile between migrants and the host population.

METHODS

A cross-sectional, population-based study was conducted in the city of São Paulo. The study population included internal migrants, defined as individuals born outside São Paulo city who had lived in the city for ten years or longer. The final population (n = 537) was divided into three groups: natives of São Paulo (45.5%), migrants from the Southeast (26.9%) and migrants from the Northeast (27.5%). The joint interim statement consensus criteria were used for diagnosing MetSyn. Diet quality was estimated using the revised version of the Brazilian Healthy Eating Index (BHEI-R). Comparisons between the data of BHEI-R, cardiometabolic risk factors and MetSyn in migrants and natives were performed using generalized linear models adjusted for confounding factors, respectively.

RESULTS

Southeastern and Northeastern migrants younger than 60 years had a higher average of for whole fruit and oil components, respectively. Northeastern migrants older than 60 years had higher systolic and diastolic blood pressure, atherogenic ratio concentrations, lower HDL-C and were more likely to present metabolic syndrome compared to those born in São Paulo of the same age group.

CONCLUSION

Native and internal migrants from Brazil resident in São Paulo exhibited differences in diet quality and cardiometabolic risk factors.

Drudgery reduction, physical activity and energy requirements in rural livelihoods

Low and middle-income countries in Asia and Africa have been witnessing a process of rural transformation, characterised by rising agricultural productivity, commercialisation of agriculture, improved infrastructure and access to services, over several decades. However, there is little empirical evidence on how this transformation process has affected the patterns and intensity of physical activity and time use in rural livelihoods. The lack of empirical evidence can be attributed to the constraints in accurate measurement of physical activity and energy expenditure in the context of free-living populations. Using wearable accelerometry devices, we develop robust energy expenditure profiles for men and women in rural households for two case studies in India and Ghana. An innovative feature of this study is the integration of data on energy expenditure (derived from accelerometers) with data on time-use, which has hitherto not been feasible in observational studies of rural populations. Using the data on physical activity, energy expenditure and time use from the case studies, we examine the impact of drudgery reduction- the substitution of less intense for more intense activities - on energy requirements for men and women in rural households. Our results show that drudgery reduction can have large effects on human energy (calorie) requirements, with an hour of drudgery reduction reducing energy requirements by 11-22 % for men and 13-17 % for women in Ghana and India. There are significant gender differences in energy expenditure patterns and drudgery reduction effects vary by socio-demographic characteristics and endowments of households. Our results suggest that drudgery reduction can offer rural households an important route to improved nutritional status. At the same time, drudgery reduction can lead to increased incidence of overweight and obesity for some segments of the population. The design of development interventions needs to explicitly consider the effects on nutrition and well-being through the energy expenditure dimension.

Social-Psychological Factors in Food Consumption of Rural Residents: The Role of Perceived Need and Habit within the Theory of Planned Behavior

To address the problem of malnutrition in poor rural areas of China, this study aims to examine the effects of social-psychological factors in food consumption of rural residents in poor counties of Southwest China. In addition, it investigates the role of perceived need and habit within the theory of planned behavior (TPB) in predicting food consumption. A survey with random sampling was conducted on rural residents (n = 424), and the theoretical frameworks of both the standard and extended TPB were applied for comparison purposes. Structural equation modeling was applied to test the relationships among constructs. Consumption of five food items was studied, respectively: meat, eggs, dairy, fish, and fruits. Results showed that incorporation of perceived need and habit substantially increased the explanatory power of the TPB, but these factors only had significant direct effects on intention rather than behavior. Perceived need and habit are stronger predictors of intention than any other TPB construct for consumption of all food items except for meat. We found indirect effects of the constructs in the extended TPB model on consumption to be different across food items. Practical implications to improve consumption of different food items were proposed accordingly.

Physical activity, time use, and food intakes of rural households in Ghana, India, and Nepal

With more than 820 million undernourished people living in rural areas of low- and middle-income countries (LMICs), ending hunger and ensuring access to food by all is a global priority. In the past few decades, the adoption of technological innovations in the agricultural sector and related crop yield improvements have not led to expected improvements in the nutritional status of rural households in many LMICs. The increased energy expenditure associated with the adoption of productivity-enhancing innovations may provide an important explanation of the disconnect between agricultural productivity enhancements and improved nutritional outcomes. We develop a methodology for generating reliable livelihood energy/calorie expenditure profiles for rural agricultural households using research-grade accelerometer devices. We integrate the data on physical activity and energy expenditure in rural households with data on time-use and food intakes to generate a data set that provides a unique window into rural livelihoods. This can be a valuable resource to analyse agriculture-nutrition impact pathways and improve the welfare of rural and agricultural households.

Sociodemographic and Regional Determinants of Dietary Patterns in Russia

An empirical assessment of diets using a posteriori analysis allows us to define actual dietary patterns (DPs) in the food consumption structure of a population. This study represents an a posteriori assessment of DPs for the Russian population in general as well as their dependence on socio-demographic and regional parameters. The data were obtained from 21,923 individuals aged 25-64 years old from a Russian multicenter study of "Epidemiology of Cardiovascular Diseases in the Regions of the Russian Federation" conducted in 2013-2014. Cross-sectional study subjects were interviewed face-to-face in order to obtain data on their diet. DPs were defined using principal component analysis. Four DPs were specified as "Rational", "Salt", "Meat", and "Mixed"; all these variants together accounted for 55.9% of variance. Diets in gender and age groups corresponded to those for an all-Russian population; in several regions, the defined diets differed from the all-Russian ones. More favorable diet trends were observed among women, people with no family, people not working, and urban dwellers, and diet trends were more favorable with an increase in age, level of education, and material wealth. Thus, a posteriori DPs were defined for the Russian population, which were stable in sex/age groups and were mediated by the socio-demographic characteristics of the population.

Influence of internal migration on body mass index: Results of the ELSA-Brasil study

OBJECTIVES

To investigate the association between internal migration and body mass index (BMI) in the adult population with data from the Brazilian Longitudinal Study of Adult Health (ELSA-Brasil) and to determine whether the association differs by the urban hierarchical levels (or influence regions) of Brazilian municipalities.

METHODS

Baseline data from 13 084 participants aged 35 to 74 (2008-2010) in the ELSA-Brasil were analyzed. A migrant was defined as an individual whose municipality of residence at the beginning of schooling (origin) was different from the municipality of residence at the study baseline (destination). The origin and destination municipalities were classified by urban hierarchical levels, or influence regions, and migration was categorized as nonmigrant, stable migrant, downward migrant, or upward migrant.

RESULTS

Of the ELSA-Brasil participants, 51% were migrants. Using gamma regression models, it was observed that for women and men, upward migration was associated with lower mean BMI after adjusting for age, mother's education level, participant's education level, and income. Downward migration, on the other hand, was associated with the highest mean BMI, but this result was statistically significant only for women.

CONCLUSION

These findings highlight the role of environmental factors on nutritional status, noting that the effects on BMI may be positive or negative, depending on the trajectory of displacements between origin and destination.

Vegetarian Epidemiology: Review and Discussion of Findings from Geographically Diverse Cohorts

Epidemiologic cohort studies enrolling a large percentage of vegetarians have been highly informative regarding the nutritional adequacy and possible health effects of vegetarian diets. The 2 largest such cohorts are the European Prospective Investigation into Cancer and Nutrition-Oxford (EPIC-Oxford) and the Adventist Health Study-2 (AHS-2). These cohorts are described and their findings discussed, including a discussion of where findings appear to diverge. Although such studies from North America and the United Kingdom have been important, the large majority of the world's vegetarians live in other regions, particularly in Asia. Findings from recent cohort studies of vegetarians in East and South Asia are reviewed, particularly the Tzu Chi Health Study and Indian Migration Study. Important considerations for the study of the health of vegetarians in Asia are discussed. Vegetarian diets vary substantially, as may associated health outcomes. Cohort studies remain an important tool to better characterize the health of vegetarian populations around the globe.

Nutrition transition, overweight and obesity among rural-to-urban migrant women in Kenya

OBJECTIVE

To assess the effect of rural-to-urban migration on nutrition transition and overweight/obesity risk among women in Kenya.

DESIGN

Secondary analysis of data from nationally representative cross-sectional samples. Outcome variables were women's BMI and nutrition transition. Nutrition transition was based on fifteen different household food groups and was adjusted for socio-economic and demographic characteristics. Stepwise backward multiple ordinal regression analysis was applied.

SETTING

Kenya Demographic and Health Survey 2014.

PARTICIPANTS

Rural non-migrant, rural-to-urban migrant and urban non-migrant women aged 15-49 years (n 6171).

RESULTS

Crude data analysis showed rural-to-urban migration to be associated with overweight/obesity risk and nutrition transition. After adjustment for household wealth, no significant differences between rural non-migrants and rural-to-urban migrants for overweight/obesity risk and household consumption of several food groups characteristic of nutrition transition (animal-source, fats and sweets) were observed. Regardless of wealth, migrants were less likely to consume main staples and legumes, and more likely to consume fruits and vegetables. Identified predictive factors of overweight/obesity among migrant women were age, duration of residence in urban area, marital status and household wealth.

CONCLUSIONS

Our analysis showed that nutrition transition and overweight/obesity risk among rural-to-urban migrants is apparent with increasing wealth in urban areas. Several predictive factors were identified characterising migrant women being at risk for overweight/obesity. Future research is needed which investigates in depth the association between rural-to-urban migration and wealth to address inequalities in diet and overweight/obesity in Kenya.

Dimensions of internal migration and their relationship to blood pressure in South Africa

Hypertension prevalence is on the rise in low- and middle-income countries (LMICs) like South Africa, and migration and its concomitant urbanization are often considered to be associated with this rise. However, relatively little is known about the relationship between blood pressure (BP) and internal migration - a highly prevalent population process in LMICs. This study employed data for a group of 194 adult men and women from an original pilot dataset drawn from the Agincourt Health and Demographic Surveillance System in north-east South Africa conducted in 2012. Migrants in the sample were identified, tracked and interviewed. The relationship between BP and migration distance and the number of months an individual spent away from his/her home village was estimated using robust OLS regression, controlling for a series of socioeconomic, health and behavioural characteristics. It was found that migrants who moved a longer distance and for longer durations had significantly higher systolic and diastolic blood pressures compared with shorter-term migrants and those who remained nearby or in their home village. These associations remained robust and statistically significant when adjusting for measures of socioeconomic conditions, as well as body mass index and the number of meals consumed per day. Migration, both in terms of distance and time away, explained significant variation in the blood pressure of migrants in this typical South African context. The findings suggest the need for further studies of the nutritional and psycho-social factors associated with geographic mobility that may be important to understand rising hypertension levels in LMICs.

Urban environment as an independent predictor of insulin resistance in a South Asian population

Background

Developing countries, such as India, are experiencing rapid urbanization, which may have a major impact on the environment: including worsening air and water quality, noise and the problems of waste disposal. We used health data from an ongoing cohort study based in southern India to examine the relationship between the urban environment and homeostasis model assessment of insulin resistance (HOMA-IR).

Methods

We utilized three metrics of urbanization: distance from urban center; population density in the India Census; and satellite-based land cover. Restricted to participants without diabetes (N = 6350); we built logistic regression models adjusted for traditional risk factors to test the association between urban environment and HOMA-IR.

Results

In adjusted models, residing within 0–20 km of the urban center was associated with an odds ratio for HOMA-IR of 1.79 (95% CI 1.39, 2.29) for females and 2.30 (95% CI 1.64, 3.22) for males compared to residing in the furthest 61–80 km distance group. Similar statistically significant results were identified using the other metrics.

Conclusions

We identified associations between urban environment and HOMA-IR in a cohort of adults. These associations were robust using various metrics of urbanization and adjustment for individual predictors. Our results are of public health concern due to the global movement of large numbers of people from rural to urban areas and the already large burden of diabetes.

Electronic supplementary material

The online version of this article (10.1186/s12942-019-0169-9) contains supplementary material, which is available to authorized users.

Migration and cognitive function: a conceptual framework for Global Health Research

BACKGROUND

Migration is a fundamental demographic process that has been observed globally. It is suggested that migration is an issue of global health importance that can have an immediate and lasting impact on an individual's health and well-being. There is now an increasing body of evidence linking migration with cognitive function in older adults. In this paper, we synthesized the current evidence to develop a general conceptual framework to understand the factors contributing to the association between migration and cognitive function.

METHODS

A comprehensive review of the literature was conducted on the associations between migration and cognition among middle-aged and older adults.

RESULTS

Five potential mechanisms were identified from the literature: 1) socioeconomic status-including education, occupation, and income; 2) psychosocial factors-including social networks, social support, social stressors, and discrimination; 3) behavioral factors-including smoking, drinking, and health service utilization; 4) physical and psychological health status-including chronic conditions, physical function, and depression; and 5) environmental factors-including both physical and social environment. Several underlying factors were also identified-including early-life conditions, gender, and genetic factors.

CONCLUSIONS

The factors linking migration and cognitive function are multidimensional and complex. This conceptual framework highlights potential implications for global health policies and planning on healthy aging and migrant health. Additional studies are needed to further examine these mechanisms to extend and refine our general conceptual framework.

Risk factors for self-reported diabetes among Bhutanese adults: A nationally representative survey data analysis

Background

Bhutan, a small land-locked country in the eastern Himalayas has been undergoing an epidemiological and nutritional transition in the last two decades. The objective of this paper was to determine the prevalence and explore the risk factors of self-reported diabetes among Bhutanese adults.

Methods

We conducted a secondary data analysis among adults 18 years and older Bhutanese using the data from the National Health Survey 2012 (NHS, 2012) of Bhutan. The self-reported information on risk factors was obtained using standard protocols of the WHO STEPwise approach to Surveillance. The outcome of interest was self-reported diabetes on medication. Adjusted and unadjusted logistic regression analyses were performed to identify the risk factor of diabetes.

Results

A total of 31,066 participants aged 18 years and older were included for the analysis. The prevalence of self-reported hypertension was 1.8% (491). Risk factors for diabetes were: age groups: 35–44 years adjusted odds ratio (AOR) = 2.82 (95% CI, 1.07, 7.41), 45–54 years AOR = 6.02 (95% CI, 2.29, 15.83), 55–64 year AOR = 15.7 (95% CI 5.93, 41.55) and >65 years AOR = 19.60 (95% CI, 6.93, 55.71); high school and diploma/certificate education AOR = 2.57, (95% CI 1.62, 4.07) and AOR = 3.92 (95% CI 1.70, 9.07); and urban dwellers AOR = 2.37, (95% 1.58, 3.57); hypertension AOR = 3.3, (95% CI 2.47, 4.41); and fruit servings of 1–3 per week AOR = 1.63 (95% CI 1.15, 2.31).

Conclusion

The number of Bhutanese adults with diabetes and co-morbidities associated with it is likely to increase with the ageing of the population, nutrition transition, and high rural-urban migration in the near future. This calls for an urgent need to implement strategies to prevent diabetes in the Bhutanese population targeting risk factors including healthy lifestyle with increased physical activities and reduced smoking. At the same time treating other chronic morbidities including hypertension.

Addressing the impact of urban exposure on the incidence of type 2 diabetes mellitus: The PERU MIGRANT Study

The aim of this study was to estimate the incidence of T2DM in three population groups: rural, rural-to-urban migrants and urban dwellers. Data from the PERU MIGRANT Study was analysed. The baseline assessment was conducted in 2007-2008 using a single-stage random sample and further follow-up was undertaken in 2015-16. T2DM was defined based on fasting glucose and self-reported diagnosis. Poisson regression models and robust variance to account for cluster effects were used for reporting risk ratios (RR) and 95%CI. At baseline, T2DM prevalence was 8% in urban, 3.6% in rural-to-urban migrants and 1.5% in rural dwellers. After 7.7 (SD: 1.1) years, 6,076 person-years of follow-up, 61 new cases were identified. The incidence rates in the urban, migrant and rural groups were 1.6, 0.9 and 0.5 per 100 person-years, respectively. Relative to rural dwellers, a 4.3-fold higher risk (95%CI: 1.6-11.9) for developing T2DM was found in urban dwellers and 2.7-fold higher (95%CI: 1.1-6.8) in migrants with ≥30 years of urban exposure. Migration and urban exposure were found as significant risk factors for developing T2DM. Within-country migration is a sociodemographic phenomenon occurring worldwide; thus, it is necessary to disentangle the effect of urban exposure on non-healthy habits and T2DM development.

Geographic differences in overweight and obesity prevalence in Peruvian children, 2010-2015

Background

Childhood obesity is emerging as a major public health problem worldwide. To date, most studies of obesity and overweight in Peru are focused on adults, with few of them involving children, a population at a critical stage of development. The trend in overweight and obesity prevalence in Peruvian children under the age of five has not yet been determined. Thus, the objective of the present study is to evaluate the prevalence rates of overweight and obesity between 2010 and 2015 in children under the age of five, stratified by geographical areas in Peru.

Methods

Data were obtained from the Nutritional Status Information System of Peru. The total number of children evaluated was 14,155,914. For the Geographic Information Systems (GIS), the program Geo Da 1.8® was used to ascertain the spatial distribution of prevalence rates and was mapped for children under five. To assess the degree of spatial dependence, exploratory spatial data analysis was performed using the Moran’s I statistic and was assessed with the Local Indicators of Spatial Association (LISA) analysis to identify geographic concentrations of high and low of obesity and overweight levels.

Results

Between 2010 and 2015, the national prevalence of childhood overweight and obesity ranged from 6.2%- 6.8% and 1.5%–2.7%, respectively. The highest prevalence of childhood overweight and obesity was found in 2014 and 2013, respectively. During these years, we observed that obesity decreased, but overweight remained stable. The highest prevalence of overweight and obesity was found in the departments located on the coast. Significant positive spatial autocorrelation was found for both overweight and obesity. The departments with the highest prevalence of overweight and obesity were concentrated in Lima, Callao, Ica, Moquegua and Tacna. The lowest were found in Loreto, Cusco and San Martin.

Conclusion

The decrease in obesity and the stabilisation of overweight are positive results for the Peruvian childhood. However, in comparison with other Latin American countries, Peru still lags in obesity prevention.

Invited review: Learning from the future-A vision for dairy farms and cows in 2067

The world's population will reach 10.4 billion in 2067, with 81% residing in Africa or Asia. Arable land available for food production will decrease to 0.15 ha per person. Temperature will increase in tropical and temperate zones, especially in the Northern Hemisphere, and this will push growing seasons and dairy farming away from arid areas and into more northern latitudes. Dairy consumption will increase because it provides essential nutrients more efficiently than many other agricultural systems. Dairy farming will become modernized in developing countries and milk production per cow will increase, doubling in countries with advanced dairying systems. Profitability of dairy farms will be the key to their sustainability. Genetic improvements will include emphasis on the coding genome and associated noncoding epigenome of cattle, and on microbiomes of dairy cattle and farmsteads. Farm sizes will increase and there will be greater lateral integration of housing and management of dairy cattle of different ages and production stages. Integrated sensors, robotics, and automation will replace much of the manual labor on farms. Managing the epigenome and microbiome will become part of routine herd management. Innovations in dairy facilities will improve the health of cows and permit expression of natural behaviors. Herds will be viewed as superorganisms, and studies of herds as observational units will lead to improvements in productivity, health, and well-being of dairy cattle, and improve the agroecology and sustainability of dairy farms. Dairy farmers in 2067 will meet the world's needs for essential nutrients by adopting technologies and practices that provide improved cow health and longevity, profitable dairy farms, and sustainable agriculture.

Association between empirically derived dietary patterns with blood lipids, fasting blood glucose and blood pressure in adults - the India migration study

BACKGROUND

Dietary patterns (DPs) in India are heterogenous. To date, data on association of indigenous DPs in India with risk factors of nutrition-related noncommunicable diseases (cardiovascular disease and diabetes), leading causes of premature death and disability, are limited. We aimed to evaluate the associations of empirically-derived DPs with blood lipids, fasting glucose and blood pressure levels in an adult Indian population recruited across four geographical regions of India.

METHODS

We used cross-sectional data from the Indian Migration Study (2005-2007). Study participants included urban migrants, their rural siblings and urban residents and their urban siblings from Lucknow, Nagpur, Hyderabad and Bangalore (n = 7067, mean age 40.8 yrs). Information on diet (validated interviewer-administered, 184-item semi-quantitative food frequency questionnaire), tobacco consumption, alcohol intake, physical activity, medical history, as well as anthropometric measurements were collected. Fasting-blood samples were collected for estimation of blood lipids and glucose. Principal component analysis (PCA) was used to identify major DPs based on eigenvalue> 1 and component interpretability. Robust standard error multivariable linear regression models were used to investigate the association of DPs (tertiles) with total cholesterol (TC), low density lipoprotein-cholesterol (LDL-C), high density lipoprotein-cholesterol (HDL-C), triglycerides, fasting-blood glucose (FBG), systolic and diastolic blood pressure (SBP and DBP) levels.

RESULTS

Three major DPs were identified: 'cereal-savoury' (cooked grains, rice/rice-based dishes, snacks, condiments, soups, nuts), 'fruit-vegetable-sweets-snacks' (Western cereals, vegetables, fruit, fruit juices, cooked milk products, snacks, sugars, sweets) and 'animal food' (red meat, poultry, fish/seafood, eggs) patterns. High intake of the 'animal food' pattern was positively associated with levels of TC (β = 0.10 mmol/L; 95% CI: 0.02, 0.17 mmol/L; p-trend = 0.013); LDL-C (β = 0.07 mmol/L; 95% CI: 0.004, 0.14 mmol/L; p-trend = 0.041); HDL-C (β = 0.02 mmol/L; 95% CI: 0.004, 0.04 mmol/L; p-trend = 0.016), FBG: (β = 0.09 mmol/L; 95% CI: 0.01, 0.16 mmol/L; p-trend = 0.021) SBP (β = 1.2 mm/Hg; 95% CI: 0.1, 2.3 mm/Hg; p-trend = 0.032); DBP: (β = 0.9 mm/Hg; 95% CI: 0.2, 1.5 mm/Hg; p-trend = 0.013). The 'cereal-savoury' and 'fruit-vegetable-sweets-snacks' patterns showed no association with any parameter except for a positive association with diastolic blood pressure for high intake of 'fruits-vegetables-sweets-snacks' pattern.

CONCLUSION

Our results indicate positive associations of the 'animal food' pattern with cardio-metabolic risk factors in India. Further longitudinal assessments of dietary patterns in India are required to validate the findings.

Risk Factors for Obesity and Overfat among Primary School Children in Mashonaland West Province, Zimbabwe

Associated childhood obesity risk factors are not well established in developing countries such as Zimbabwe and this information is essential for tailored intervention development. This study aimed to identify prominent risk factors for overweight/obese and overfat/obese among primary school children of Mashonaland West Province in Zimbabwe. A school-based cross-sectional study was conducted using multi-stage random cluster sampling approach (30 × 30). Bivariate and multivariable logistic regression was employed and identified the risk factors for overweight/obese and overfat/obese. A total of 974 participants were enrolled in the study. Prominent significant risk factors of overweight/obese after multivariable adjustment were higher socio-economic households; parental diabetes status; and living in Makonde, Zvimba, Sanyati or Mhondoro-Ngezi district as opposed to Hurungwe district. Risk factors for overfat/obese that remained statically significant were children in urban areas (aOR = 3.19, 95% CI: 2.18-4.66, p = 0.000), being one child in a household, and parents who have diabetes mellitus. Living in Makonde, Sanyati, and Zvimba district remained associated with overfat/obese compared to Hurungwe district. This study has identified prominent proximal determinants of overweight/obese and overfat/obese among primary school children in Zimbabwe, to better assist policy guidance. Aggressive education on good nutrition activities should be tailored and targeted to most affected urban areas within high-risk districts.

Dietary patterns in internal migrants in a continental country: A population-based study

OBJECTIVE

The objective of this study was to assess the differences and similarities in dietary patterns among migrants and natives.

METHODS

A population-based, cross-sectional study was conducted in the city of São Paulo. The study population included internal migrants, defined as individuals born outside São Paulo city who had lived in the city for ten years or longer. The final population (n = 999) was divided into three groups: natives of São Paulo (n = 354), migrants from the Southeast (n = 349) and migrants from the Northeast (n = 296). Factor and principal component analysis was employed to derive dietary patterns. The standardized scores were compared among groups using linear regression.

RESULTS

Differences in income per capita, years of education, self-reported race, smoking habits, alcohol consumption, nutritional status and prevalence of hypertension were found for place of birth. Three dietary patterns were identified: prudent (salad dressings, vegetables, natural flavorings, fruits, whole-grain bread, white cheeses and juices), traditional (rice, beans, bread/toast/crackers, butter/margarine, whole milk, coffee/teas, sugar), and modern (sodas, pastries/sandwiches/pizzas, yellow cheeses, pastas, sauces, alcoholic beverages, sweets, processed meats). Compared to natives, migrants from the Southeast had an inversely proportional adherence to the modern pattern whereas migrants from the Northeast had an inverse association with the prudent and modern patterns and a positive association with the traditional pattern.

CONCLUSIONS

São Paulo natives and internal migrants from other regions of Brazil exhibited different dietary patterns. The results presented here add perspectives to be considered in the study of non-communicable diseases and its different incidences among migrants and natives.

Determinants of internal migrant health and the healthy migrant effect in South India: a mixed methods study

Background

Internal labour migration is an important and necessary livelihood strategy for millions of individuals and households in India. However, the precarious position of migrant workers within Indian society may have consequences for the health of these individuals. Previous research on the connections between health and labour mobility within India have primarily focused on the negative health outcomes associated with this practice. Thus, there is a need to better identify the determinants of internal migrant health and how these determinants shape migrant health outcomes.

Methods

An exploratory mixed methods study was conducted in 26 villages in the Krishnagiri district of Tamil Nadu. Sixty-six semi-structured interviews were completed using snowball sampling, followed by 300 household surveys using multi-stage random sampling. For qualitative data, an analysis of themes and content was completed. For quantitative data, information on current participation in internal labour migration, in addition to self-reported morbidity and determinants of internal migrant health, was collected. Morbidity categories were compared between migrant and non-migrant adults (age 14–65 years) using a Fisher’s exact test.

Results

Of the 300 households surveyed, 137 households (45.7%) had at least one current migrant member, with 205 migrant and 1012 non-migrant adults (age 14–65 years) included in this study.

The health profile of migrant and non-migrants was similar in this setting, with 53 migrants (25.9%) currently suffering from a health problem compared to 273 non-migrants (27.0%). Migrant households identified both occupational and livelihood factors that contributed to changes in the health of their migrant members. These determinants of internal migrant health were corroborated and further expanded on through the semi-structured interviews.

Conclusions

Internal labour migration in and of itself is not a determinant of health, as participation in labour mobility can contribute to an improvement in health, a decline in health, or no change in health among migrant workers. Targeted public health interventions should focus on addressing the determinants of internal migrant health to enhance the contributions these individuals can make to their households and villages of origin.

Dietary patterns and non-communicable disease risk in Indian adults: secondary analysis of Indian Migration Study data

OBJECTIVE

Undernutrition and non-communicable disease (NCD) are important public health issues in India, yet their relationship with dietary patterns is poorly understood. The current study identified distinct dietary patterns and their association with micronutrient undernutrition (Ca, Fe, Zn) and NCD risk factors (underweight, obesity, waist:hip ratio, hypertension, total:HDL cholesterol, diabetes).

DESIGN

Data were from the cross-sectional Indian Migration Study, including semi-quantitative FFQ. Distinct dietary patterns were identified using finite mixture modelling; associations with NCD risk factors were assessed using mixed-effects logistic regression models.

SETTING

India.

SUBJECTS

Migrant factory workers, their rural-dwelling siblings and urban non-migrants. Participants (7067 adults) resided mainly in Karnataka, Andhra Pradesh, Maharashtra and Uttar Pradesh.

RESULTS

Five distinct, regionally distributed, dietary patterns were identified, with rice-based patterns in the south and wheat-based patterns in the north-west. A rice-based pattern characterised by low energy consumption and dietary diversity ('Rice & low diversity') was consumed predominantly by adults with little formal education in rural settings, while a rice-based pattern with high fruit consumption ('Rice & fruit') was consumed by more educated adults in urban settings. Dietary patterns met WHO macronutrient recommendations, but some had low micronutrient contents. Dietary pattern membership was associated with several NCD risk factors.

CONCLUSIONS

Five distinct dietary patterns were identified, supporting sub-national assessments of the implications of dietary patterns for various health, food system or environment outcomes.

The water use of Indian diets and socio-demographic factors related to dietary blue water footprint

Agriculture accounts for ~90% of India's fresh water use, and there are concerns that future food production will be threatened by insufficient water supply of adequate quality. This study aimed to quantify the water required in the production of diets in India using the water footprint (WF) assessment method. The socio-demographic associations of dietary WFs were explored using mixed effects regression models with a particular focus on blue (irrigation) WF given the importance for Indian agriculture. Dietary data from ~7000 adults living in India were matched to India-specific WF data for food groups to quantify the blue and green (rainfall) WF of typical diets. The mean blue and green WF of diets was 737l/capita/day and 2531l/capita/day, respectively. Vegetables had the lowest WFs per unit mass of product, while roots/tubers had the lowest WFs per unit dietary energy. Poultry products had the greatest blue WFs. Wheat and rice contributed 31% and 19% of the dietary blue WF respectively. Vegetable oils were the highest contributor to dietary green WF. Regional variation in dietary choices meant large differences in dietary blue WFs, whereby northern diets had nearly 1.5 times greater blue WFs than southern diets. Urban diets had a higher blue WF than rural diets, and a higher standard of living was associated with larger dietary blue WFs. This study provides a novel perspective on the WF of diets in India using individual-level dietary data, and demonstrates important variability in WFs due to different food consumption patterns and socio-demographic characteristics. Future dietary shifts towards patterns currently consumed by individuals in higher income groups, would likely increase irrigation requirements putting substantial pressure on India's water resources.

Comparison of food consumption in Indian adults between national and sub-national dietary data sources

Accurate data on dietary intake are important for public health, nutrition and agricultural policy. The National Sample Survey is widely used by policymakers in India to estimate nutritional outcomes in the country, but has not been compared with other dietary data sources. To assess relative differences across available Indian dietary data sources, we compare intake of food groups across six national and sub-national surveys between 2004 and 2012, representing various dietary intake estimation methodologies, including Household Consumption Expenditure Surveys (HCES), FFQ, food balance sheets (FBS), and 24-h recall (24HR) surveys. We matched data for relevant years, regions and economic groups, for ages 16-59. One set of national HCES and the 24HR showed a decline in food intake in India between 2004-2005 and 2011-2012, whereas another HCES and FBS showed an increase. Differences in intake were smallest between the two HCES (1 % relative difference). Relative to these, FFQ and FBS had higher intake (13 and 35 %), and the 24HR lower intake (-9 %). Cereal consumption had high agreement across comparisons (average 5 % difference), whereas fruit and nuts, eggs, meat and fish and sugar had the least (120, 119, 56 and 50 % average differences, respectively). Spearman's coefficients showed high correlation of ranked food group intake across surveys. The underlying methods of the compared data highlight possible sources of under- or over-estimation, and influence their relevance for addressing various research questions and programmatic needs.

Greenhouse gas emissions from agricultural food production to supply Indian diets: Implications for climate change mitigation

Agriculture is a major source of greenhouse gas (GHG) emissions globally. The growing global population is putting pressure on agricultural production systems that aim to secure food production while minimising GHG emissions. In this study, the GHG emissions associated with the production of major food commodities in India are calculated using the Cool Farm Tool. GHG emissions, based on farm management for major crops (including cereals like wheat and rice, pulses, potatoes, fruits and vegetables) and livestock-based products (milk, eggs, chicken and mutton meat), are quantified and compared. Livestock and rice production were found to be the main sources of GHG emissions in Indian agriculture with a country average of 5.65 kg CO₂eq kg^-1 rice, 45.54 kg CO₂eq kg^-1 mutton meat and 2.4 kg CO₂eq kg^-1 milk. Production of cereals (except rice), fruits and vegetables in India emits comparatively less GHGs with <1 kg CO₂eq kg^-1 product. These findings suggest that a shift towards dietary patterns with greater consumption of animal source foods could greatly increase GHG emissions from Indian agriculture. A range of mitigation options are available that could reduce emissions from current levels and may be compatible with increased future food production and consumption demands in India.

Rural-to-urban migration and risk of hypertension: longitudinal results of the PERU MIGRANT study

Urbanization can be detrimental to health in populations due to changes in dietary and physical activity patterns. The aim of this study was to determine the effect of migration on the incidence of hypertension. Participants of the PERU MIGRANT study, that is, rural, urban and rural-to-urban migrants, were re-evaluated after 5 years after baseline assessment. The outcome was incidence of hypertension; and the exposures were study group and other well-known risk factors. Incidence rates, relative risks (RRs) and population attributable fractions (PAFs) were calculated. At baseline, 201 (20.4%), 589 (59.5%) and 199 (20.1%) participants were rural, rural-to-urban migrant and urban subjects, respectively. Overall mean age was 47.9 (s.d.±12.0) years, and 522 (52.9%) were female. Hypertension prevalence at baseline was 16.0% (95% confidence interval (CI) 13.7-18.3), being more common in urban group; whereas pre-hypertension was more prevalent in rural participants (P<0.001). Follow-up rate at 5 years was 94%, 895 participants were re-assessed and 33 (3.3%) deaths were recorded. Overall incidence of hypertension was 1.73 (95%CI 1.36-2.20) per 100 person-years. In multivariable model and compared with the urban group, rural group had a greater risk of developing hypertension (RR 3.58; 95%CI 1.42-9.06). PAFs showed high waist circumference as the leading risk factor for the hypertension development in rural (19.1%), migrant (27.9%) and urban (45.8%) participants. Subjects from rural areas are at higher risk of developing hypertension relative to rural-urban migrant or urban groups. Central obesity was the leading risk factor for hypertension incidence in the three population groups.