Salome A. Rebello

Coffee and tea consumption in relation to inflammation and basal glucose metabolism in a multi-ethnic Asian population: a cross-sectional study

BackgroundHigher coffee consumption has been associated with a lower risk of type 2 diabetes in cohort studies, but the physiological pathways through which coffee affects glucose metabolism are not fully understood. The aim of this study was to evaluate the associations between habitual coffee and tea consumption and glucose metabolism in a multi-ethnic Asian population and possible mediation by inflammation.MethodsWe cross-sectionally examined the association between coffee, green tea, black tea and Oolong tea consumption and glycemic (fasting plasma glucose, HOMA-IR, HOMA-beta, plasma HbA1c) and inflammatory (plasma adiponectin and C-reactive protein) markers in a multi-ethnic Asian population (N = 4139).ResultsAfter adjusting for multiple confounders, we observed inverse associations between coffee and HOMA-IR (percent difference: - 8.8% for ≥ 3 cups/day versus rarely or never; Ptrend = 0.007), but no significant associations between coffee and inflammatory markers. Tea consumption was not associated with glycemic markers, but green tea was inversely associated with plasma C-reactive protein concentrations (percent difference: - 12.2% for ≥ 1 cup/day versus < 1 cup/week; Ptrend = 0.042).ConclusionsThese data provide additional evidence for a beneficial effect of habitual caffeinated coffee consumption on insulin sensitivity, and suggest that this effect is unlikely to be mediated by anti-inflammatory mechanisms.

Coffee Consumption and Cardiovascular Health: Getting to the Heart of the Matter

As coffee-consumption is a widespread tradition, its possible impact on health has been of considerable interest. This review examines the effects of coffee on cardiovascular risk, outlines underlying biological mechanisms, and discusses implications for public health. In the past, coffee was often viewed as a cardiovascular risk-factor. However, in meta-analyses of recent well-controlled prospective epidemiologic studies, coffee-consumption was not associated with risk of coronary heart disease and weakly associated with a lower risk of stroke and heart failure. Also, available evidence largely suggests that coffee-consumption is not associated with a higher risk of fatal cardiovascular events. In randomized trials coffee-consumption resulted in small increases in blood pressure. Unfiltered coffee increased circulating LDL cholesterol and triglycerides concentrations, but filtered coffee had no substantial effects on blood lipids. In summary, for most healthy people, moderate coffee consumption is unlikely to adversely affect cardiovascular health. Future work should prioritize understanding the effects of coffee in at-risk populations.

Amount, type, and sources of carbohydrates in relation to ischemic heart disease mortality in a Chinese population: a prospective cohort study

BACKGROUND The relation between carbohydrate intake and risk of ischemic heart disease (IHD) has not been fully explored in Asian populations known to have high-carbohydrate diets. OBJECTIVE We assessed whether intakes of total carbohydrates, different types of carbohydrates, and their food sources were associated with IHD mortality in a Chinese population. DESIGN We prospectively examined the association of carbohydrate intake and IHD mortality in 53,469 participants in the Singapore Chinese Health Study with an average follow-up of 15 y. Diet was assessed by using a semiquantitative food-frequency questionnaire. HRs and 95% CIs were calculated by using a Cox proportional hazards analysis. RESULTS We documented 1660 IHD deaths during 804,433 person-years of follow-up. Total carbohydrate intake was not associated with IHD mortality risk [men: HR per 5% of energy, 0.97 (95% CI: 0.92, 1.03); women: 1.06 (95% CI: 0.99, 1.14)]. When types of carbohydrates were analyzed individually, starch intake was associated with higher risk [men: 1.03 (95% CI: 0.99, 1.08); women: 1.08, (95% CI: 1.02, 1.14)] and fiber intake with lower risk of IHD mortality [men: 0.94 (95% CI: 0.82, 1.08); women: 0.71 (95% CI: 0.60, 0.84)], with stronger associations in women than men (both P-interaction < 0.01). In substitution analyses, the replacement of one daily serving of rice with one daily serving of noodles was associated with higher risk (difference in HR: 26.11%; 95% CI: 10.98%, 43.30%). In contrast, replacing one daily serving of rice with one of vegetables (-23.81%; 95% CI: -33.12%, -13.20%), fruit (-11.94%; 95% CI: -17.49%, -6.00%), or whole-wheat bread (-19.46%; 95% CI: -34.28%, -1.29%) was associated with lower risk of IHD death. CONCLUSIONS In this Asian population with high carbohydrate intake, the total amount of carbohydrates consumed was not substantially associated with IHD mortality. In contrast, the shifting of food sources of carbohydrates toward a higher consumption of fruit, vegetables, and whole grains was associated with lower risk of IHD death.

Salt Intakes and Salt Reduction Initiatives in Southeast Asia: A Review

Increased dietary sodium intake is a modifiable risk factor for cardiovascular disease. The monitoring of population sodium intake is a key part of any salt reduction intervention. However, the extent and methods used for as-sessment of sodium intake in Southeast Asia is currently unclear. This paper provides a narrative synthesis of the best available evidence regarding levels of sodium intake in six Southeast Asian countries: Indonesia, Malaysia, Philippines, Singapore, Thailand, Vietnam, and describes salt reduction measures being undertaken in these countries. Electronic databases were screened to identify relevant articles for inclusion up to 29 February 2012. Reference lists of included studies and conference proceedings were also examined. Local experts and researchers in nutrition and public health were consulted. Quality of studies was assessed using a modified version of the Downs and Black Checklist. Twenty-five studies fulfilled the inclusion criteria and were included in this review. Full texts of 19 studies including government reports were retrieved, with most studies being of good quality. In-sufficient evidence exists regarding salt intakes in Southeast Asia. Dietary data suggest that sodium intake in most SEA countries exceeded the WHO recommendation of 2 g/day. Studies are needed that estimate sodium intake using the gold standard 24-hour urinary sodium excretion. The greatest proportion of dietary sodium came from added salt and sauces. Data on children were limited. The six countries had salt reduction initiatives that differed in specificity and extent, with greater emphasis on consumer education.

Development of a Semi-Quantitative Food Frequency Questionnaire to Assess the Dietary Intake of a Multi-Ethnic Urban Asian Population

Assessing habitual food consumption is challenging in multi-ethnic cosmopolitan settings. We systematically developed a semi-quantitative food frequency questionnaire (FFQ) in a multi-ethnic population in Singapore, using data from two 24-h dietary recalls from a nationally representative sample of 805 Singapore residents of Chinese, Malay and Indian ethnicity aged 18–79 years. Key steps included combining reported items on 24-h recalls into standardized food groups, developing a food list for the FFQ, pilot testing of different question formats, and cognitive interviews. Percentage contribution analysis and stepwise regression analysis were used to identify foods contributing cumulatively ≥90% to intakes and individually ≥1% to intake variance of key nutrients, for the total study population and for each ethnic group separately. Differences between ethnic groups were observed in proportions of consumers of certain foods (e.g., lentil stews, 1%–47%; and pork dishes, 0%–50%). The number of foods needed to explain variability in nutrient intakes differed substantially by ethnic groups and was substantially larger for the total population than for separate ethnic groups. A 163-item FFQ covered >95% of total population intake for all key nutrients. The methodological insights provided in this paper may be useful in developing similar FFQs in other multi-ethnic settings.

Determinants of individuals' participation in integrated chronic disease screening in Singapore.

Background A large pool of patients with chronic diseases remains undiagnosed globally and in Singapore. We explored factors associated with participation in a health screening exercise, using revealed preference, that is, actual attendance, to understand why people remain undiagnosed with chronic diseases. Methods A cross-sectional, community-based sample of Singapore residents was invited to participate in home interviews, and subsequently to attend centre-based health screening, between 2004 and 2007. Determinants of health screening participation were identified using logistic regression models based on Andersens Behavioral Model. Results Of the 6366 participants who completed health interview, 4092 attended the health screening, while 2274 did not. Older age, Chinese or Indian ethnicity, higher education levels, greater intake of monounsaturated fat, greater transport and leisure-time physical activity were the key predisposing factors associated with greater health screening participation. Greater family cohesion was the key associated enabling factor, while previous diagnosis of dyslipidaemia or musculoskeletal conditions, absence of previously diagnosed diabetes or hypertension and lower perceived physical health were the associated need factors. Conclusions Our study suggests that ethnicity, education, family cohesion, healthy behaviour patterns and perceived physical health status were key determinants of health screening participation. Enhancing the cultural competence of preventive health services may help increase participation of these groups in screening efforts and reduce the proportions of undiagnosed chronic disease in the community.

Relative Validity and Reproducibility of a Food Frequency Questionnaire for Assessing Dietary Intakes in a Multi-Ethnic Asian Population Using 24-h Dietary Recalls and Biomarkers

The assessment of diets in multi-ethnic cosmopolitan settings is challenging. A semi-quantitative 163-item food frequency questionnaire (FFQ) was developed for the adult Singapore population, and this study aimed to assess its reproducibility and relative validity against 24-h dietary recalls (24 h DR) and biomarkers. The FFQ was administered twice within a six-month interval in 161 adults (59 Chinese, 46 Malay, and 56 Indian). Fasting plasma, overnight urine, and 24 h DR were collected after one month and five months. Intra-class correlation coefficients between the two FFQ were above 0.70 for most foods and nutrients. The median correlation coefficient between energy-adjusted deattenuated FFQ and 24 h DR nutrient intakes was 0.40 for FFQ1 and 0.39 for FFQ2, highest for calcium and iron, and lowest for energy and carbohydrates. Significant associations were observed between urinary isoflavones and soy protein intake (r = 0.46), serum carotenoids and fruit and vegetable intake (r = 0.34), plasma eicosapentaenoic acid and docosahexaenoic acid (EPA + DHA) and fish/seafood intake (r = 0.36), and plasma odd chain saturated fatty acids (SFA) and dairy fat intake (r = 0.25). Associations between plasma EPA + DHA and fish/seafood intake were consistent across ethnic groups (r = 0.28–0.49), while differences were observed for other associations. FFQ assessment of dietary intakes in modern cosmopolitan populations remains feasible for the purpose of ranking individuals’ dietary exposures in epidemiological studies.

Determinants of eating at local and western fast-food venues in an urban Asian population: a mixed methods approach

BackgroundLike several Southeast Asian countries, Singapore has a complex eating-out environment and a rising eating-out prevalence. However the determinants and drivers of eating-out in urban Asian environments are poorly understood.MethodsWe examined the socio-demographic characteristics of persons who frequently ate away from home in local eateries called hawker centres and Western fast-food restaurants, using data from 1647 Singaporean adults participating in the National Nutrition Survey (NNS) 2010. We also assessed the underlying drivers of eating out and evaluated if these were different for eating at local eateries compared to Western fast-food restaurants using 18 focus group discussions of women (130 women).ResultsParticipants reported a high eating-out frequency with 77.3% usually eating either breakfast, lunch or dinner at eateries. Main venues for eating-out included hawker centres (61.1% usually ate at least 1 of 3 daily meals at this venue) and school/workplace canteens (20.4%). A minority of participants (1.9%) reported usually eating at Western fast-food restaurants. Younger participants and those of Chinese and Malay ethnicity compared to Indians were more likely to eat at Western fast-food restaurants. Chinese and employed persons were more likely to eat at hawker centres. The ready availability of a large variety of affordable and appealing foods appeared to be a primary driver of eating out, particularly at hawker centres.ConclusionsOur findings highlight the growing importance of eating-out in an urban Asian population where local eating venues play a more dominant role compared with Western fast-food chains. Interventions focusing on improving the food quality at venues for eating out are important to improve the diet of urban Asian populations.

Infant Feeding Practices in a Multi-Ethnic Asian Cohort: The GUSTO Study.

The optimal introduction of complementary foods provides infants with nutritionally balanced diets and establishes healthy eating habits. The documentation of infant feeding practices in multi-ethnic Asian populations is limited. In a Singapore cohort study (GUSTO), 842 mother-infant dyads were interviewed regarding their feeding practices when the infants were aged 9 and 12 months. In the first year, 20.5% of infants were given dietary supplements, while 5.7% took probiotics and 15.7% homeopathic preparations. At age 9 months, 45.8% of infants had seasonings added to their foods, increasing to 56.3% at 12 months. At age 12 months, 32.7% of infants were given blended food, although 92.3% had begun some form of self-feeding. Additionally, 87.4% of infants were fed milk via a bottle, while a third of them had food items added into their bottles. At both time points, more than a third of infants were provided sweetened drinks via the bottle. Infants of Indian ethnicity were more likely to be given dietary supplements, have oil and seasonings added to their foods and consumed sweetened drinks from the bottle (p < 0.001). These findings provide a better understanding of variations in infant feeding practices, so that healthcare professionals can offer more targeted and culturally-appropriate advice.

A randomized placebo-controlled trial of the effect of coffee consumption on insulin sensitivity: Design and baseline characteristics of the Coffee for METabolic Health (COMETH) study

Background Coffee consumption has been consistently associated with a lower risk of type 2 diabetes mellitus in cohort studies. In addition, coffee components increased insulin sensitivity in animal models. However, data from intervention studies on the effect of coffee consumption on glucose metabolism have been limited by small sample sizes, lack of blinding, short follow-up duration and the use of surrogate indices of insulin sensitivity. We designed the Coffee for Metabolic Health (COMETH) study to evaluate the effect of coffee consumption on insulin sensitivity. Methodology The COMETH study is a double-blind randomized placebo-controlled 24-week trial. Participants were overweight, male and female habitual coffee consumers who were of Chinese, Malay and Asian-Indian ethnicity. We excluded smokers, persons with diabetes, and persons with low insulin resistance (HOMA-IR < 1.30). Participants were randomly assigned to receive daily 4 cups of instant regular coffee or 4 cups of a coffee-like placebo beverage. The hyperinsulinemic euglycemic clamp was performed at baseline and at the end of 24 weeks to determine changes in the bodyweight standardized M-value. Secondary outcomes included changes in fasting glucose and insulin sensitivity mediators such as adiponectin, markers of inflammation, liver function, and oxidative stress. We enrolled 128 participants, 126 (57.1% males; aged 35–67 years) of whom completed baseline assessments. Discussion If improvement in insulin sensitivity in the coffee group is significantly greater than that of the placebo group, this would support the hypothesis that coffee consumption reduced risk of type 2 diabetes through biological pathways involving insulin sensitivity. Trial registration ClinicalTrials.gov identifier: NCT01738399. Registered on 28 November 2012. Trial Sponsor: Nestlé Research Center, Lausanne, Switzerland. Trial Site: National University of Singapore.