DIABETICMedicine DOI: 10.1111/dme.13081
Short Report: Epidemiology When’s dinner? Does timing of dinner affect the cardiometabolic risk profiles of South-Asian Canadians at risk for diabetes Supna K. Sandhu and Tricia S. Tang Division of Endocrinology and Metabolism, University of British Columbia, Vancouver, Canada Accepted 19 January 2016
Abstract Aim To explore the relationship between the time dinner is consumed (dinnertime or timing of dinner) and cardiometabolic risk factors among South-Asian Canadians at risk for diabetes. Methods We recruited 432 South-Asian adults affiliated with Sikh and Hindu Temples in Metro Vancouver. Participants deemed to be at risk of diabetes underwent a clinical and behavioural assessment. Dinnertime was measured via self-report. Clinical endpoints included HbA1c, apolipoprotein, blood pressure, weight, BMI and waist circumference.
The mean age of participants was 65 years and 59% were male. Dinnertime was categorized into three groups: early (before 18:00 h); average (18:00 to 20:00 h); and late (later than 20:00 h). Among the participants, 19% (n = 79), 44% (n = 187) and 37% (n = 157) reported early, average and late dinnertimes, respectively. Significant differences were found for dinnertime groups and years of residence in Canada, gender and employment. Compared with the early dinnertime group, the late dinnertime group lived in Canada for a shorter duration, comprised a higher proportion of males (66 vs 48%; P = 0.01) and were currently employed (37 vs 22%; P = 0.02). With regard to clinical endpoints, compared with the early dinnertime group, the late dinnertime group had lower systolic blood pressure (135.9 vs 131.7 mmHg; P = 0.03). After controlling for demographic characteristics, this difference was diminished. No significant differences were found between dinnertime and HbA1c, apolipoprotein, diastolic blood pressure, weight, BMI and waist circumference. Results
Findings suggest that, among this sample of South-Asian Canadians at risk of Type 2 diabetes, there was no association between timing of the evening meal and cardiometabolic profiles.
Conclusion
Diabet. Med. 00, 000–000 (2016)
Introduction South Asians in Canada have one of the highest rates of coronary heart disease and metabolic syndrome compared with other ethnicities, and tend to develop these diseases years earlier [1–4]. They represent one of the country’s largest growing ethnic groups, with ~75% having immigrated from elsewhere [1]. As a result of immigration, SouthAsian people may adopt a more Westernized lifestyle and become susceptible to the health burdens associated with the dominant culture. Given this phenomenon, there has been greater attention given to acculturation and the increased
Correspondence to: Supna K. Sandhu. E-mail: [email protected]
ª 2016 Diabetes UK
cardiovascular risk in Canada’s South-Asian community [1– 5]. Among lifestyle risk factors, low engagement in physical activity and high consumption of Westernized food (e.g. simple sugars and refined foods) has been reported by SouthAsian immigrants in Canada, the USA and the UK [4–6]. These dietary patterns become more prominent as the length of residence in the new host country increases [6]. Previous research has found that diets high in refined carbohydrates and sugar-sweetened beverages have been associated with a decrease in HDL cholesterol, an increase in insulin resistance, an increase in obesity and, overall, a less favourable metabolic profile [7]. Although the relationship between specific dietary food intake and metabolic syndrome has been established, the
1
DIABETICMedicine
relationship between time of meal consumption and cardiometabolic risk factors in South Asians has been under-investigated. Existing studies in non-South-Asian populations have reported later evening mealtimes to be correlated with an increased rate of obesity, hyperglycaemia and dyslipidaemia [8–10]. The only study that examined mealtime in the South-Asian community was conducted in the UK. Simmons et al. [11] found that South Asians reported, on average, evening meal times 2–3 h later than their European counterparts, but absent in this investigation was the exploration of timing of meals and health-related factors. The aim of the present study was to address the following questions. (1) What is the profile of evening mealtimes for South-Asian Canadians at risk of diabetes and what demographic factors is this related to? (2) What is the relationship between the timing of dinner and cardiometabolic risk factors (HbA1c, apolipoprotein B, blood pressure, waist circumference and BMI) for this community?
Patients and methods This cross-sectional study was approved by the University of British Columbia and Fraser Health Clinical Research Ethics Boards and is part of a larger investigation exploring health profiles and lifestyle behaviours in Canadian South Asians at risk of diabetes. We recruited a convenience sample of South Asian adults affiliated with Sikh and Hindu temples in the Metro Vancouver area between July 2013 and June 2014. A two-stage eligibility screening process was used. For initial screening, individuals had to: 1) identify as South Asian; 2) be aged ≥21 years; 3) speak Punjabi and/or English; and 4) live in the Metro Vancouver area. If deemed eligible, follow-up screening required individuals to complete the American Diabetes Association diabetes risk test. This consists of seven items that assess age, gender, history of gestational diabetes, family history of diabetes, diagnosis of hypertension, physical activity status and weight status. Individuals who scored ≥5 (out of a possible 11 points) were deemed eligible. Those interested in participating provided informed consent and enrolled in the study. Assessment included the clinical and behavioural measures described below.
Measures
Dinnertime (i.e. the timing of dinner) was assessed via an interviewer-administered survey and posed the following question, ‘On average, what time do you eat dinner (or supper) every evening?’. Metabolic and cardiovascular measures were collected in person at assessment sessions and included HbA1c, apolipoprotein B, systolic and diastolic blood pressure, weight, BMI and waist circumference. HbA1c and apolipoprotein B were obtained via venous puncture.
2
South Asian dinnertime S. K. Sandhu and T. S. Tang
Sociodemographic characteristics were self-reported and included age, gender, marital status, education level, income, years in Canada and employment status.
Statistical analysis
The demographic characteristics were summarized for all participants and separately for the early, average and late dinnertime group. Continuous variables were expressed as means and standard deviations. Categorical variables were reported as percentages. Comparisons between groups were conducted with the use of a two-sample t-test for continuous data and a chi-squared or Fisher’s exact test as appropriate for categorical data. A linear regression model was fitted for each clinical outcome. In the model, the clinical outcome was the response variable and the dinner group was the primary variable of interest. The model was adjusted for age and gender. All analyses were performed in SAS 9.4. Reported P-values were two-sided. A P value < 0.05 was considered to indicate statistical significance.
Results Demographic and clinical characteristics
Participants (n = 432) had a mean age of 65 years and were 59% male. Education was lower than high-school level in 48% of participants, 54% were retired, 86% were currently married, 90% identified as Sikh, 93% spoke Punjabi as their primary language and 27% reported a household income of < $20,000 CAD. The mean BMI was 28.18 3.99 kg/m2 with a mean waist circumference of 103.14 9.93 cm for men and 99.62 10.69 for women. The mean systolic and diastolic blood pressure was 134.31 17.32 mmHg and 80.46 42 mmol/mol, respectively, the mean HbA1c level was 5.97 0.73% and the mean apolipoprotein B level was 0.99 0.25 mmol/l. Relationship between the timing of dinner and demographic characteristics
Data on the timing of dinner were available for 423 participants. The timing of dinner was stratified into three categories: early (before 18:00 h), average (18:00 to 20:00 h), and late (later than 20:00 h). Dinnertimes for 19% of participants (n = 79) were classified as early, 44% (n = 187) as average, and 37% (n = 157) as late. Significant group differences (P < 0.0001) were found for years of residence in Canada with early, average and late groups reporting means of 35, 24 and 17 years, respectively. Significant group differences between early and late groups were also found for gender and employment, with the late group more likely to be male (66.03 vs. 48.10%; P = 0.01) and currently employed (36.94 vs 21.79%; P = 0.02) ª 2016 Diabetes UK
Research article
DIABETICMedicine
compared with the early group. Significant group differences between the average and late groups were found for marital status and employment, with the late group more likely to be currently married (91.08 vs 81.72%; P = 0.01) and currently employed (36.94 vs 20.97%; P = 0.001) than the average group. No significant group differences were found for age, English proficiency, education and household income.
Relationship between the timing of dinner and cardiometabolic risk factors
Table 1 shows the clinical characteristics by dinnertime categories. A significant group difference between early and late groups was found for systolic blood pressure, with the early group having higher values than the late group (135.9 vs 131.7 mmHg; P = 0.03); however, that difference lost significance after adjusting for age, gender, martial status, education, income, employment and years living in Canada. No significant group differences were found for HbA1c, apolipoprotein B, BMI, weight, waist circumference, or diastolic BP.
Discussion This is the first study to investigate the relationship between the timing of dinner and cardiometabolic risk factors among South-Asian Canadian adults at risk of diabetes. In contrast to previous research suggesting that consuming meals later rather than earlier in the evening has a deleterious impact on cardiometabolic profiles [6–8], we found no relationship between the timing of dinner and glycaemic control, apolipoprotein B, blood pressure, weight, BMI and waist circumference (after controlling for demographic characteristics). It is possible that, in the South-Asian community, the timing of dinner is a distal rather than proximal factor associated with cardiometabolic risk factors. Instead, food composition may play a more significant role. Considering
that the traditional South- Asian diet consists of foods high in fat, salt, simple sugars and carbohydrates, and food preparation relies heavily on deep frying or sauteing in ghee (i.e. clarified butter), these dietary patterns may exert the greatest impact on health outcomes. In fact, previous studies have found that higher consumption of sugar-sweetened beverages and alcohol in this population may contribute to increased abdominal obesity, thereby leading to negative cardiometabolic consequences [1,4,5]. Moreover, a recent meta-analysis by Brown et al. [12] found that culturally tailored dietary counselling emphasizing food choice and food preparation (rather than the timing of dinner) led to a lower BMI in South-Asian adults in the UK; thus, lifestyle modification interventions targeting the South-Asian community should avoid recommendations that, although seemingly benign (eating dinner earlier in the evening rather than later), are not yet evidence-based. Another possible explanation for the lack of group differences in cardiometabolic profiles is participants’ preexisting health status. Specifically, those individuals with few to no cardiometabolic risk factors before the study may not be concerned with adopting an earlier dinnertime as it has not had an influence on their health, to date. Consistent with the study by Simmons et al. [11] in a South-Asian population in the UK, approximately one-third of participants reported a late dinnertime. The fact that the present findings showed an association between the timing of dinner and years of residence in Canada suggest that acculturation does have an impact on dietary patterns. Specifically, the longer an individual lives in Canada, the more likely the individual will have an earlier dinner. The present study has some limitations. First, this investigation was not originally powered to detect a relationship between the timing of dinner and cardiometabolic risk factors. With a larger sample size, we may have found an effect. In addition, we measured dinnertime using self-report which is subject to potential bias. For instance, it may be socially desirable to report an earlier dinnertime as this is
Table 1 Cardiometabolic characteristics, stratified by early (before 18:00 h), average (18:00 to 20:00 h) or late (after 20:00 h) dinnertime in SouthAsian Canadians Variable
Early dinner (n = 79)
Average dinner (n = 187)
Late dinner (n = 157)
P
HbA1c, mmol/lmol HbA1c, % Apolipoprotein B, g/l Systolic blood pressure, mmHg Diastolic blood pressure, mmHg Weight, kg BMI, kg/m2 Male waist circumference, cm Female waist circumference, cm
41 5.90 0.50 0.99 0.21 136.72 14.71 81.97 9.01 75.35 11.31 28.055.9 3.55 101.36 9.98 98.95 9.54
40 5.94 0.68 1 0.27 135.75 18.96 80.21 10.57 76.20 12.37 28.45 4.13 103.93 8.94 100.90 11.86
42 6.03 1.01 131.68 80.15 75.98 27.84 102.45 98.39
0.16‡ 0.16‡ 0.57† 0.02†,‡ 0.19† 0.61* 0.15† 0.14* 0.19‡
0.89 0.26 15.61 10.05 12.60 3.59 9.01 9.63
*P value between early and average dinner groups. † P value for early vs late dinner groups. ‡ P value for average vs late dinner groups.
ª 2016 Diabetes UK
3
South Asian dinnertime S. K. Sandhu and T. S. Tang
DIABETICMedicine
generally considered to be more healthy. Finally, given that the present study population was older and there was a mean BMI of 28 kg/m2 across all three groups, results are not generalizable to the larger population. Moreover, because participants were recruited exclusively from faith-based institutions, the findings may not even reflect the SouthAsian community overall. Future research should examine these questions with a more representative sample. Making dietary changes is inherently challenging, especially if the alteration impinges on cultural habits and traditions. With the increasing rate of metabolic syndrome for South-Asian immigrants, we need to better understand the lifestyle and dietary patterns of this community, how acculturation influences these behaviours, and what lifestyle modifications are important in promoting health and preventing disease.
3
4
5
6
7
8
Funding sources
We would like to thank the Vancouver Foundation, Heart and Stroke Foundation and Sanofi Aventis for funding this study.
9
10
Competing interests
None declared.
11
References
12
1 Rana A, de Souza RJ, Kandasamy S, Lear S, Anand SS. Cardiovascular risk among South Asians living in Canada: a systematic review and meta-analysis. CMAJ 2014; 2: E183–E191. 2 Anand SS, Yusuf S, Vuksan V, Devanesen S, Teo KK, Montague PA et al. Differences in risk factors, atherosclerosis and cardiovascular
4
disease between ethnic groups in Canada: the Study of Health Assessment and Risk in Ethnic groups (SHARE). Lancet 2000; 356: 279–284. Nijjar AP, Wang H, Quan H, Khan NA. Ethnic and sex differences in the incidence of hospitalized acute myocardial infarction: British Columbia, Canada 1995–2002. BMC Cardiovasc Disord 2010; 10: 38. Gadgil M, Anderson CA, Kandula NR, Kanaya AM. Dietary Patterns in Asian Indians in the United States: An Analysis of the Metabolic Syndrome and Atherosclerosis in South Asians Living in America Study. J Acad Nutr Diet 2014; 114: 238–243. Gardu~ no-Diaz SD, Khokhar S. South Asian dietary patterns and their association with risk factors for the metabolic syndrome. J Hum Nutr Diet 2012; 26: 145–155. Lesser IA, Gasevic D, Lear SA. The Association between Acculturation and Dietary Patterns of South Asian Immigrants. PloS One 2014; 9: 1–6. Holmboe-Ottesen G, Wandel M. Changes in dietary habits after migration and consequences for health: a focus on South Asians in Europe. Food Nutr Res 2012; 56: 1–13. Baron KG, Reid KJ, Horn LV, Zee PC. Contribution of evening macronutrient intake to total caloric intake and body mass index. Appetite 2013; 60: 246–251. Morgan ML, Shi JW, Hampton SM, Frost G. Effect of meal timing and glycaemic index on glucose control and insulin secretion in healthy volunteers. Br J Nutr 2012; 108: 1286–1291. Yoshizaki T, Tada Y, Hida A, Sunami A, Yokoyama Y, Yasuda J et al. Effects of feeding schedule changes on the circadian phase of the cardiac autonomic nervous system and serum lipid levels. Eur J Appl Physiol 2013; 113: 2603–2611. Simmons D, Williams R. Dietary practices among Europeans and different South Asian groups in Coventry. Br J Nutr 1997; 78: 5– 14. Brown T, Smith S, Bhopal R, Kasim A, Summerbell C. Diet and physical activity interventions to prevent or treat obesity in South Asian children and adults: a systematic review and meta-analysis. Int J Environ Res Public Health 2015; 12: 566–594.
ª 2016 Diabetes UK
Short Report: Epidemiology When’s dinner? Does timing of dinner affect the cardiometabolic risk profiles of South-Asian Canadians at risk for diabetes Supna K. Sandhu and Tricia S. Tang Division of Endocrinology and Metabolism, University of British Columbia, Vancouver, Canada Accepted 19 January 2016
Abstract Aim To explore the relationship between the time dinner is consumed (dinnertime or timing of dinner) and cardiometabolic risk factors among South-Asian Canadians at risk for diabetes. Methods We recruited 432 South-Asian adults affiliated with Sikh and Hindu Temples in Metro Vancouver. Participants deemed to be at risk of diabetes underwent a clinical and behavioural assessment. Dinnertime was measured via self-report. Clinical endpoints included HbA1c, apolipoprotein, blood pressure, weight, BMI and waist circumference.
The mean age of participants was 65 years and 59% were male. Dinnertime was categorized into three groups: early (before 18:00 h); average (18:00 to 20:00 h); and late (later than 20:00 h). Among the participants, 19% (n = 79), 44% (n = 187) and 37% (n = 157) reported early, average and late dinnertimes, respectively. Significant differences were found for dinnertime groups and years of residence in Canada, gender and employment. Compared with the early dinnertime group, the late dinnertime group lived in Canada for a shorter duration, comprised a higher proportion of males (66 vs 48%; P = 0.01) and were currently employed (37 vs 22%; P = 0.02). With regard to clinical endpoints, compared with the early dinnertime group, the late dinnertime group had lower systolic blood pressure (135.9 vs 131.7 mmHg; P = 0.03). After controlling for demographic characteristics, this difference was diminished. No significant differences were found between dinnertime and HbA1c, apolipoprotein, diastolic blood pressure, weight, BMI and waist circumference. Results
Findings suggest that, among this sample of South-Asian Canadians at risk of Type 2 diabetes, there was no association between timing of the evening meal and cardiometabolic profiles.
Conclusion
Diabet. Med. 00, 000–000 (2016)
Introduction South Asians in Canada have one of the highest rates of coronary heart disease and metabolic syndrome compared with other ethnicities, and tend to develop these diseases years earlier [1–4]. They represent one of the country’s largest growing ethnic groups, with ~75% having immigrated from elsewhere [1]. As a result of immigration, SouthAsian people may adopt a more Westernized lifestyle and become susceptible to the health burdens associated with the dominant culture. Given this phenomenon, there has been greater attention given to acculturation and the increased
Correspondence to: Supna K. Sandhu. E-mail: [email protected]
ª 2016 Diabetes UK
cardiovascular risk in Canada’s South-Asian community [1– 5]. Among lifestyle risk factors, low engagement in physical activity and high consumption of Westernized food (e.g. simple sugars and refined foods) has been reported by SouthAsian immigrants in Canada, the USA and the UK [4–6]. These dietary patterns become more prominent as the length of residence in the new host country increases [6]. Previous research has found that diets high in refined carbohydrates and sugar-sweetened beverages have been associated with a decrease in HDL cholesterol, an increase in insulin resistance, an increase in obesity and, overall, a less favourable metabolic profile [7]. Although the relationship between specific dietary food intake and metabolic syndrome has been established, the
1
DIABETICMedicine
relationship between time of meal consumption and cardiometabolic risk factors in South Asians has been under-investigated. Existing studies in non-South-Asian populations have reported later evening mealtimes to be correlated with an increased rate of obesity, hyperglycaemia and dyslipidaemia [8–10]. The only study that examined mealtime in the South-Asian community was conducted in the UK. Simmons et al. [11] found that South Asians reported, on average, evening meal times 2–3 h later than their European counterparts, but absent in this investigation was the exploration of timing of meals and health-related factors. The aim of the present study was to address the following questions. (1) What is the profile of evening mealtimes for South-Asian Canadians at risk of diabetes and what demographic factors is this related to? (2) What is the relationship between the timing of dinner and cardiometabolic risk factors (HbA1c, apolipoprotein B, blood pressure, waist circumference and BMI) for this community?
Patients and methods This cross-sectional study was approved by the University of British Columbia and Fraser Health Clinical Research Ethics Boards and is part of a larger investigation exploring health profiles and lifestyle behaviours in Canadian South Asians at risk of diabetes. We recruited a convenience sample of South Asian adults affiliated with Sikh and Hindu temples in the Metro Vancouver area between July 2013 and June 2014. A two-stage eligibility screening process was used. For initial screening, individuals had to: 1) identify as South Asian; 2) be aged ≥21 years; 3) speak Punjabi and/or English; and 4) live in the Metro Vancouver area. If deemed eligible, follow-up screening required individuals to complete the American Diabetes Association diabetes risk test. This consists of seven items that assess age, gender, history of gestational diabetes, family history of diabetes, diagnosis of hypertension, physical activity status and weight status. Individuals who scored ≥5 (out of a possible 11 points) were deemed eligible. Those interested in participating provided informed consent and enrolled in the study. Assessment included the clinical and behavioural measures described below.
Measures
Dinnertime (i.e. the timing of dinner) was assessed via an interviewer-administered survey and posed the following question, ‘On average, what time do you eat dinner (or supper) every evening?’. Metabolic and cardiovascular measures were collected in person at assessment sessions and included HbA1c, apolipoprotein B, systolic and diastolic blood pressure, weight, BMI and waist circumference. HbA1c and apolipoprotein B were obtained via venous puncture.
2
South Asian dinnertime S. K. Sandhu and T. S. Tang
Sociodemographic characteristics were self-reported and included age, gender, marital status, education level, income, years in Canada and employment status.
Statistical analysis
The demographic characteristics were summarized for all participants and separately for the early, average and late dinnertime group. Continuous variables were expressed as means and standard deviations. Categorical variables were reported as percentages. Comparisons between groups were conducted with the use of a two-sample t-test for continuous data and a chi-squared or Fisher’s exact test as appropriate for categorical data. A linear regression model was fitted for each clinical outcome. In the model, the clinical outcome was the response variable and the dinner group was the primary variable of interest. The model was adjusted for age and gender. All analyses were performed in SAS 9.4. Reported P-values were two-sided. A P value < 0.05 was considered to indicate statistical significance.
Results Demographic and clinical characteristics
Participants (n = 432) had a mean age of 65 years and were 59% male. Education was lower than high-school level in 48% of participants, 54% were retired, 86% were currently married, 90% identified as Sikh, 93% spoke Punjabi as their primary language and 27% reported a household income of < $20,000 CAD. The mean BMI was 28.18 3.99 kg/m2 with a mean waist circumference of 103.14 9.93 cm for men and 99.62 10.69 for women. The mean systolic and diastolic blood pressure was 134.31 17.32 mmHg and 80.46 42 mmol/mol, respectively, the mean HbA1c level was 5.97 0.73% and the mean apolipoprotein B level was 0.99 0.25 mmol/l. Relationship between the timing of dinner and demographic characteristics
Data on the timing of dinner were available for 423 participants. The timing of dinner was stratified into three categories: early (before 18:00 h), average (18:00 to 20:00 h), and late (later than 20:00 h). Dinnertimes for 19% of participants (n = 79) were classified as early, 44% (n = 187) as average, and 37% (n = 157) as late. Significant group differences (P < 0.0001) were found for years of residence in Canada with early, average and late groups reporting means of 35, 24 and 17 years, respectively. Significant group differences between early and late groups were also found for gender and employment, with the late group more likely to be male (66.03 vs. 48.10%; P = 0.01) and currently employed (36.94 vs 21.79%; P = 0.02) ª 2016 Diabetes UK
Research article
DIABETICMedicine
compared with the early group. Significant group differences between the average and late groups were found for marital status and employment, with the late group more likely to be currently married (91.08 vs 81.72%; P = 0.01) and currently employed (36.94 vs 20.97%; P = 0.001) than the average group. No significant group differences were found for age, English proficiency, education and household income.
Relationship between the timing of dinner and cardiometabolic risk factors
Table 1 shows the clinical characteristics by dinnertime categories. A significant group difference between early and late groups was found for systolic blood pressure, with the early group having higher values than the late group (135.9 vs 131.7 mmHg; P = 0.03); however, that difference lost significance after adjusting for age, gender, martial status, education, income, employment and years living in Canada. No significant group differences were found for HbA1c, apolipoprotein B, BMI, weight, waist circumference, or diastolic BP.
Discussion This is the first study to investigate the relationship between the timing of dinner and cardiometabolic risk factors among South-Asian Canadian adults at risk of diabetes. In contrast to previous research suggesting that consuming meals later rather than earlier in the evening has a deleterious impact on cardiometabolic profiles [6–8], we found no relationship between the timing of dinner and glycaemic control, apolipoprotein B, blood pressure, weight, BMI and waist circumference (after controlling for demographic characteristics). It is possible that, in the South-Asian community, the timing of dinner is a distal rather than proximal factor associated with cardiometabolic risk factors. Instead, food composition may play a more significant role. Considering
that the traditional South- Asian diet consists of foods high in fat, salt, simple sugars and carbohydrates, and food preparation relies heavily on deep frying or sauteing in ghee (i.e. clarified butter), these dietary patterns may exert the greatest impact on health outcomes. In fact, previous studies have found that higher consumption of sugar-sweetened beverages and alcohol in this population may contribute to increased abdominal obesity, thereby leading to negative cardiometabolic consequences [1,4,5]. Moreover, a recent meta-analysis by Brown et al. [12] found that culturally tailored dietary counselling emphasizing food choice and food preparation (rather than the timing of dinner) led to a lower BMI in South-Asian adults in the UK; thus, lifestyle modification interventions targeting the South-Asian community should avoid recommendations that, although seemingly benign (eating dinner earlier in the evening rather than later), are not yet evidence-based. Another possible explanation for the lack of group differences in cardiometabolic profiles is participants’ preexisting health status. Specifically, those individuals with few to no cardiometabolic risk factors before the study may not be concerned with adopting an earlier dinnertime as it has not had an influence on their health, to date. Consistent with the study by Simmons et al. [11] in a South-Asian population in the UK, approximately one-third of participants reported a late dinnertime. The fact that the present findings showed an association between the timing of dinner and years of residence in Canada suggest that acculturation does have an impact on dietary patterns. Specifically, the longer an individual lives in Canada, the more likely the individual will have an earlier dinner. The present study has some limitations. First, this investigation was not originally powered to detect a relationship between the timing of dinner and cardiometabolic risk factors. With a larger sample size, we may have found an effect. In addition, we measured dinnertime using self-report which is subject to potential bias. For instance, it may be socially desirable to report an earlier dinnertime as this is
Table 1 Cardiometabolic characteristics, stratified by early (before 18:00 h), average (18:00 to 20:00 h) or late (after 20:00 h) dinnertime in SouthAsian Canadians Variable
Early dinner (n = 79)
Average dinner (n = 187)
Late dinner (n = 157)
P
HbA1c, mmol/lmol HbA1c, % Apolipoprotein B, g/l Systolic blood pressure, mmHg Diastolic blood pressure, mmHg Weight, kg BMI, kg/m2 Male waist circumference, cm Female waist circumference, cm
41 5.90 0.50 0.99 0.21 136.72 14.71 81.97 9.01 75.35 11.31 28.055.9 3.55 101.36 9.98 98.95 9.54
40 5.94 0.68 1 0.27 135.75 18.96 80.21 10.57 76.20 12.37 28.45 4.13 103.93 8.94 100.90 11.86
42 6.03 1.01 131.68 80.15 75.98 27.84 102.45 98.39
0.16‡ 0.16‡ 0.57† 0.02†,‡ 0.19† 0.61* 0.15† 0.14* 0.19‡
0.89 0.26 15.61 10.05 12.60 3.59 9.01 9.63
*P value between early and average dinner groups. † P value for early vs late dinner groups. ‡ P value for average vs late dinner groups.
ª 2016 Diabetes UK
3
South Asian dinnertime S. K. Sandhu and T. S. Tang
DIABETICMedicine
generally considered to be more healthy. Finally, given that the present study population was older and there was a mean BMI of 28 kg/m2 across all three groups, results are not generalizable to the larger population. Moreover, because participants were recruited exclusively from faith-based institutions, the findings may not even reflect the SouthAsian community overall. Future research should examine these questions with a more representative sample. Making dietary changes is inherently challenging, especially if the alteration impinges on cultural habits and traditions. With the increasing rate of metabolic syndrome for South-Asian immigrants, we need to better understand the lifestyle and dietary patterns of this community, how acculturation influences these behaviours, and what lifestyle modifications are important in promoting health and preventing disease.
3
4
5
6
7
8
Funding sources
We would like to thank the Vancouver Foundation, Heart and Stroke Foundation and Sanofi Aventis for funding this study.
9
10
Competing interests
None declared.
11
References
12
1 Rana A, de Souza RJ, Kandasamy S, Lear S, Anand SS. Cardiovascular risk among South Asians living in Canada: a systematic review and meta-analysis. CMAJ 2014; 2: E183–E191. 2 Anand SS, Yusuf S, Vuksan V, Devanesen S, Teo KK, Montague PA et al. Differences in risk factors, atherosclerosis and cardiovascular
4
disease between ethnic groups in Canada: the Study of Health Assessment and Risk in Ethnic groups (SHARE). Lancet 2000; 356: 279–284. Nijjar AP, Wang H, Quan H, Khan NA. Ethnic and sex differences in the incidence of hospitalized acute myocardial infarction: British Columbia, Canada 1995–2002. BMC Cardiovasc Disord 2010; 10: 38. Gadgil M, Anderson CA, Kandula NR, Kanaya AM. Dietary Patterns in Asian Indians in the United States: An Analysis of the Metabolic Syndrome and Atherosclerosis in South Asians Living in America Study. J Acad Nutr Diet 2014; 114: 238–243. Gardu~ no-Diaz SD, Khokhar S. South Asian dietary patterns and their association with risk factors for the metabolic syndrome. J Hum Nutr Diet 2012; 26: 145–155. Lesser IA, Gasevic D, Lear SA. The Association between Acculturation and Dietary Patterns of South Asian Immigrants. PloS One 2014; 9: 1–6. Holmboe-Ottesen G, Wandel M. Changes in dietary habits after migration and consequences for health: a focus on South Asians in Europe. Food Nutr Res 2012; 56: 1–13. Baron KG, Reid KJ, Horn LV, Zee PC. Contribution of evening macronutrient intake to total caloric intake and body mass index. Appetite 2013; 60: 246–251. Morgan ML, Shi JW, Hampton SM, Frost G. Effect of meal timing and glycaemic index on glucose control and insulin secretion in healthy volunteers. Br J Nutr 2012; 108: 1286–1291. Yoshizaki T, Tada Y, Hida A, Sunami A, Yokoyama Y, Yasuda J et al. Effects of feeding schedule changes on the circadian phase of the cardiac autonomic nervous system and serum lipid levels. Eur J Appl Physiol 2013; 113: 2603–2611. Simmons D, Williams R. Dietary practices among Europeans and different South Asian groups in Coventry. Br J Nutr 1997; 78: 5– 14. Brown T, Smith S, Bhopal R, Kasim A, Summerbell C. Diet and physical activity interventions to prevent or treat obesity in South Asian children and adults: a systematic review and meta-analysis. Int J Environ Res Public Health 2015; 12: 566–594.
ª 2016 Diabetes UK
