Fast eating and the risk of type 2 diabetes mellitus: A case-control study

Eating behaviors and incidence of type 2 diabetes in Japanese people: The population-based Panasonic cohort study 15

AIM/INTRODUCTION

This historical cohort study sought to research the relationship between eating behaviors and the incidence of type 2 diabetes in a large, long-term cohort of Japanese subjects.

MATERIALS AND METHODS

Panasonic Corporation employees who had no history of diabetes and attended yearly health surveys between 2008 and 2018 were included in this study. The main outcome measure was diabetes onset.

RESULTS

This study included 128,594 participants and 6,729 participants who developed type 2 diabetes in the study period. Skipping breakfast, fast eating, snacking after dinner, and eating meals before sleeping were linked with the risk of the incidence of type 2 diabetes. In individuals with a BMI < 25 kg/m2, fast eating (hazard ratio [HR]: 1.61, 95% confidence interval [CI]: 1.37-1.90), and eating meals before sleeping (HR: 1.09, 95% CI: 1.02-1.17) were likewise associated with an increased risk of incident type 2 diabetes. Nevertheless, fast eating (HR: 1.08, 95% CI: 0.89-1.30) and meals before sleeping (HR: 0.94, 95% CI: 0.88-1.01) were not related to the occurrence of type 2 diabetes in individuals with a BMI ≥25 kg/m2 (P value for interaction = 0.0007 [fast eating] and 0.007 [meals before sleeping], respectively). No significant interaction effect between sex and eating behavior was found.

CONCLUSIONS

With respect to Japanese people, especially in people with a BMI < 25 kg/m2, eating behaviors may be a risk factor for the occurrence of type 2 diabetes.

Fast Eating Speed Could Be Associated with HbA1c and Salt Intake Even after Adjusting for Oral Health Status: A Cross-Sectional Study

This study aimed to examine the relationship between eating speed and hemoglobin A1c (HbA1c), considering the number of teeth, using cross-sectional health examination data from community-dwelling older individuals in Japan. We used data from the Center for Community-Based Healthcare Research and Education Study in 2019. We collected data on gender, age, body mass index, blood test results, Salt intake, bone mineral density, body fat percentage, muscle mass, basal metabolic rate, number of teeth, and lifestyle information. Eating speed was evaluated subjectively as fast, normal, or slow. Overall, 702 participants were enrolled in the study and 481 participants were analyzed. Multivariate logistic regression analysis revealed a significant association between fast eating speed and being a male (odds ratio [95% confidence interval]: 2.15 [1.02-4.53]), HbA1c (1.60 [1.17-2.19]), salt intake (1.11 [1.01-1.22]), muscle mass (1.05 [1.00-1.09]), and enough sleep (1.60 [1.03-2.50]). Fast eating may be associated with overall health and lifestyle. The characteristics of fast eaters, after taking oral information into consideration, tended to increase the risk of type 2 diabetes, renal dysfunction, and hypertension. Dental professionals should provide dietary and lifestyle guidance to fast eaters.

Meal frequency and incidence of type 2 diabetes: a prospective study

Dietary habits play an important role in the development of obesity and type 2 diabetes. However, evidence on association between diet frequency and type 2 diabetes was limited and inconclusive. We aimed to examine the association between meal frequency and risk of type 2 diabetes. The cohort study used data from China Health and Retirement Longitudinal Study of 8874 community-dwelling people aged over 45 years. Participants were classified as eating two meals per day, three meals per day and four meals per day. Multiple Poisson regression models were used to examine risk of 4-year incident type 2 diabetes among people who ate more or less than three meals per day compared with people who ate three meals per day. We documented 706 type 2 diabetes cases during follow-up. After adjustment for known risk factors for type 2 diabetes, except for BMI, participants who ate four meals per day were at a lower risk of type 2 diabetes than those who ate three meals per day (relative risk(RR) = 0·73 (0·58, 0·92)). After further adjustment for baseline BMI, the association was slightly attenuated but remained statistically significant (RR = 0·76 (0·60, 0·97)). Subgroup analysis showed that the fully adjusted RR of type 2 diabetes for people eating four meals per day were 0·66 (0·48, 0·91) and 0·93 (0·65, 1·34) among those had a BMI < 25 and ≥ 25 kg/m², respectively. Eating four meals per day, compared with eating three meals per day was associated with lower risk of developing type 2 diabetes in a Chinese population, particularly in those with a BMI < 25 kg/m².

Clinical practice advice on lifestyle modification in the management of nonalcoholic fatty liver disease in Japan: an expert review

Nonalcoholic fatty liver disease (NAFLD) is the most common cause of chronic liver diseases worldwide, including in Japan. The Japanese Society of Gastroenterology (JSGE) and the Japanese Society of Hepatology (JSH) have established the Japanese NAFLD/NASH guidelines in 2014 and revised these guidelines in 2020. As described in these guidelines, weight reduction by diet and/or exercise therapy is important for the treatment of NAFLD patients. The I148M single nucleotide polymorphism (rs738409 C > G) of PNPLA3 (patatin-like phospholipase domain-containing 3 protein) is widely known to be associated with the occurrence and progression of NAFLD. In the Japanese, the ratio of PNPLA3 gene polymorphisms found is approximately 20%, which is higher than that found in Westerners. In addition, the ratio of lean NAFLD patients is also higher in Japan than in Western countries. Therefore, the method for lifestyle guidance for the NAFLD patients in Japan would be different from that for the people in Western countries. The problems in the treatment of NAFLD patients include alcohol consumption and sarcopenia. Therefore, guidelines that can help clinicians treat Japanese patients with NAFLD are needed. In this expert review, we summarize evidence-based interventions for lifestyle modification (diet, exercise, alcohol, and sarcopenia) for the treatment of patients with NAFLD, especially from Japan and Asian countries.

Association Between Eating Speed and Metabolic Syndrome: A Systematic Review and Meta-Analysis

Objective: This review aimed to systematically summarize and meta-analyze the association between eating speed and metabolic syndrome (MetS). Methods: Following the Preferred Reporting Items for Systematic Reviews, and Meta Analyses (PRISMA) guidelines, four electronic databases (PubMed, Web of Science, MEDLINE, and EMBASE) were searched until March 2021 to identify eligible articles based on a series of inclusion and exclusion criteria. Heterogeneity was examined using I ² statistics. Using random-effects models, the pooled odds ratios (ORs), and 95% CIs were calculated to evaluate the association between eating speed with MetS and its components, including central obesity, blood pressure (BP), high-density lipoprotein cholesterol (HDL), triglyceride (TG), and fasting plasma glucose (FPG). Results: Of the 8,500 original hits generated by the systematic search, 29 eligible studies with moderate-to-high quality were included, involving 465,155 subjects. The meta-analysis revealed that eating faster was significantly associated with higher risks of MetS (OR = 1.54, 95% CI: 1.27-1.86), central obesity (OR = 1.54, 95% CI: 1.37-1.73), elevated BP (OR = 1.26, 95% CI: 1.13-1.40), low HDL (OR = 1.23, 95% CI: 1.15-1.31), elevated TG (OR = 1.29, 95% CI: 1.18-1.42), and elevated FPG (OR = 1.16, 95% CI: 1.06-1.27) compared to eating slowly. Conclusions: The results of the review indicated that eating speed was significantly associated with MetS and its components. Interventions related to decreasing eating speed may be beneficial for the management of MetS. Systematic Review Registration: https://www.crd.york.ac.uk/prospero/display_record.php?ID=CRD42021242213, identifier: CRD42021242213.

Impact of income and eating speed on new-onset diabetes among men: a retrospective cohort study

OBJECTIVE

To examine the impact of income and eating speed on new-onset diabetes among men.

DESIGN

This was a retrospective cohort study.

SETTING

We used the administrative claims and health check-up data for fiscal years 2010-2015 obtained from the Fukuoka branch of the Japan Health Insurance Association.

PARTICIPANTS

Participants were 15 474 non-diabetic male employees, aged between 40 and 74 years. They were categorised based on their eating speeds (ie, fast, normal and non-fast).

PRIMARY AND SECONDARY OUTCOME MEASURES

To calculate the OR of the development of diabetes, we created generalised linear regression models with diabetes onset as the dependent variable and eating speed and income as covariates and calculated corresponding 95% CI values. The analyses were performed after adjusting the data for age, obesity and comorbidities.

RESULTS

Of the total participants, 620 developed diabetes during the 5-year study period. A univariate analysis using the generalised linear regression model revealed that eating fast (OR: 1.35, 95% CI 1.17 to 1.55) and having a low income wereincome (OR: 1.47, 95% CI 1.24 to 1.74) were significantly associated with the onset of diabetes. After adjusting for age, obesity and comorbidities, both eating fast (OR: 1.17, 95% CI 1.02 to 1.35) and having a low income (OR: 1.24, 95% CI 1.03 to 1.50) were recognised as independent risk factors for diabetes onset.

CONCLUSIONS

The study revealed that eating fast and having a low income were independent risk factors, leading to the development of diabetes. While it is difficult to address income differences, it may be possible to address the factors that contribute to income differences to manage diabetes appropriately and at low healthcare costs. However, eating speed can be controlled. Hence, the provision of education and coaching on dietary habits, including eating speed, may be effective in preventing diabetes onset.

Eating Speed and Incidence of Diabetes in a Japanese General Population: ISSA-CKD

Background: We investigated whether eating speed was associated with the incidence of diabetes in a Japanese general population. Methods: A total of 4853 Japanese individuals without diabetes at baseline were analyzed. Self-reported eating speed was categorized as slow, medium, and fast on the basis of questionnaire responses. The study outcome was the incidence of diabetes. Results: After an average follow-up period of 5.1 years, 234 individuals developed diabetes. The incidence of diabetes per 1000 person-years was 4.9 in the slow eating speed group, 8.8 in the medium eating speed group, and 12.5 in the fast eating speed group, respectively (*** p < 0.001 for trend). The HRs were 1.69 (95%CI 0.94–3.06) for the medium eating speed and 2.08 (95%CI 1.13–3.84) for the fast eating speed, compared to the slow eating speed (* p = 0.014 for trend) after adjustment for age, gender, smoking status, drinking, exercise, obesity, hypertension, and dyslipidemia. Conclusion: Faster eating speed increased a risk for the incidence of diabetes in a general Japanese population.

Association between eating speed and newly diagnosed nonalcoholic fatty liver disease among the general population

Fast eating speed is a risk factor for obesity, which is also closely related to nonalcoholic fatty liver disease (NAFLD), suggesting that fast eating speed may contribute to the development of NAFLD. But the extent to which obesity may mediate the association between eating speed and NAFLD is uncertain. We hypothesized that obesity plays a mediating role in the association between eating speed and prevalence of NAFLD in the general population. A cross-sectional study (n = 23,611) was conducted in a general population sample from Tianjin, China. We measured anthropometrics and biochemical variables. The self-reported eating speed per meal was recorded and classified into 4 categories: slow, medium, relatively fast, and very fast. NAFLD was diagnosed by liver ultrasonography. Multiple logistic regression analysis was used to assess the associations between the eating speed and the prevalence of NAFLD, as well as the mediation effects of obesity on the association between eating speed and NAFLD. The prevalence of newly diagnosed NAFLD was 19.0%. After adjusting for potentially confounding factors, the odds ratios (95% confidence interval) of NAFLD across categories of eating speed were 1.00 (reference), 1.39 (1.18-1.64), 1.71 (1.45-2.01), and 2.04 (1.70-2.46). All these significant odds ratios were attenuated to be nonsignificant by adjustment for body mass index and/or waist circumference. This is the first study to demonstrate that eating speed is not independently associated with increased risk of NAFLD.

Eating speed and the risk of type 2 diabetes: explorations based on real-world evidence

Metabolic syndrome, especially diabetes, has gained global attention over the past few decades and became one of the major public health concerns. Alongside known and well-established risk factors, eating behaviors, mainly eating speed has shown the potential as one of the novel risk factors that could supplement the development of diabetes. However, there is a paucity in evidence, and only a few studies have addressed this question so far. In this review, with a focus on eating speed and the risk of developing diabetes, authors attempted to shed some light on the high-quality studies that were conducted around the world using real-world data in drawing inferences, which could add-on to the literature and assist public in making informed decisions.

How dietary intake of type 2 diabetes mellitus outpatients affects their fasting blood glucose levels?

OBJECTIVE

The study aims to explore the association between the adherence to dietary recommendations among type 2 diabetes mellitus (T2DM) patients with their fasting blood glucose levels.

METHOD

This is a cross-sectional anthropometric and dietary study conducted on 169 T2DM patients receiving outpatient treatment at the Central Nursing and Rehabilitation Hospital in Thanh Hoa provincial hospital in Vietnam in 2018.

RESULTS

The rate of patients who had good fasting glycemic control was still low (30.8%). Their diets were poor in energy and unbalanced; the contribution of carbohydrates to the total dietary intake was high (68.2%), and only 24.9% of patients consumed 4-6 meals/day. There was a statistically significant association between the dietary intake with carbohydrate dietary intake containing ≥60% carbohydrate and the number of meals per day (<4 meals) with their fasting blood glucose levels (OR = 4.964, p < 0.05 and OR = 16.508; p < 0.01, respectively).

CONCLUSIONS AND RECOMMENDATIONS

Hospital staff are advised to combine treatment with dietary counseling to help patients controlling their weights and glycemic levels more efficient, thereby contributing to improving their treatment outcomes.

Fast eating is a strong risk factor for new-onset diabetes among the Japanese general population

Although many studies that have examined the relationship of type and amount of food and the frequency of eating with new onset of diabetes, there are few reports on the relationship between how meals are eaten, such as skipping breakfast, snacking or food ingestion speed, and the onset of diabetes. We investigated the relationship between eating speed, as well as other eating habits such as snacking and skip breakfast, and new onset of diabetes in a nation-wide Japanese cohort. We obtained data from the nation-wide annual health check program in Japan. In 197,825 participants without diabetes in 2008, questionnaires recorded data on the diet habits (eating speed, snack after supper or before sleep, and skipping breakfast) and unadjusted and multivariable-adjusted logistic regression models were used to measure the odds ratio of new-onset diabetes mellitus in a 3-year follow up. The proportion of fast eaters, those who snack after supper, snack before sleep, and skip breakfast was higher in the new-onset diabetes group than in the group who did not develop diabetes mellitus. As compared with the non-fast eater group, fast eaters were generally younger, had higher BMI, had more weight gain from 20 years onwards, and experienced frequent weight fluctuations of ≥3 kg within 1 year. The risk of fast eaters developing diabetes mellitus remained even after correction for multiple factors including age, body weight, rate of weight change, blood pressure, smoking, and alcohol consumption. No other eating habits were independent predictors for onset of diabetes mellitus. Results show that fast eating is a sole predisposing factor among eating habits for new-onset diabetes. Future studies were warranted to evaluate whether avoidance of fast eating is beneficial for prevention of diabetes mellitus.

Systematic estimation of BMI: A novel insight into predicting overweight/obesity in undergraduates

The prevalence of overweight-obesity has increased sharply among undergraduates worldwide. In 2016, approximately 52% of adults were overweight-obese. This cross-sectional study aimed to investigate the prevalence of overweight-obesity and explore in depth the connection between eating habits and overweight-obesity among Chinese undergraduates.The study population included 536 undergraduates recruited in Shijiazhuang, China, in 2017. They were administered questionnaires for assessing demographic and daily lifestyle characteristics, including sex, region, eating speed, number of meals per day, and sweetmeat habit. Anthropometric status was assessed by calculating the body mass index (BMI). The determinants of overweight-obesity were investigated by the Pearson χ test, Spearman rho test, multivariable linear regression, univariate/multivariate logistic regression, and receiver operating characteristic curve analysis.The prevalence of undergraduate overweight-obesity was 13.6%. Sex [male vs female, odds ratio (OR): 1.903; 95% confidence interval (95% CI): 1.147-3.156], region (urban vs rural, OR: 1.953; 95% CI: 1.178-3.240), number of meals per day (3 vs 2, OR: 0.290; 95% CI: 0.137-0.612), and sweetmeat habit (every day vs never, OR: 4.167; 95% CI: 1.090-15.933) were significantly associated with overweight-obesity. Eating very fast was positively associated with overweight-obesity and showed the highest OR (vs very slow/slow, OR: 5.486; 95% CI: 1.622-18.553). However, the results of multivariate logistic regression analysis indicated that only higher eating speed is a significant independent risk factor for overweight/obesity (OR: 17.392; 95% CI, 1.614-187.363; P = .019).Scoremeng = 1.402 × scoresex + 1.269 × scoreregion + 19.004 × scoreeatin speed + 2.546 × scorenumber of meals per day + 1.626 × scoresweetmeat habit and BMI = 0.253 × Scoremeng + 18.592. These 2 formulas can help estimate the weight status of undergraduates and predict whether they will be overweight or obese.

Association between eating behavior and poor glycemic control in Japanese adults

This study investigated the relationship between eating behavior and poor glycemic control in 5,479 Japanese adults with hemoglobin A1c (HbA1c) <6.5% who participated in health checks. Respondents to a 2013 baseline survey of eating behavior, including skipping breakfast and how quickly they consumed food were followed up until 2017. We defined poor glycemic control after follow-up as HbA1c ≥6.5%, or increases in HbA1c of ≥0.5% and/or being under medication to control diabetes. We identified 109 (2.0%) respondents who met these criteria for poor glycemic control. After adjusting for sex, age, smoking status, body mass index (BMI), and eating behavior, the risk of poor glycemic control was increased in males (odds ratio [OR], 2.38; 95% confidence interval [CI] 1.37–4.12; p < 0.01), and associated with being older (OR, 1.07; 95% CI, 1.04–1.11; p < 0.001), having a higher BMI (OR, 1.29; 95% CI 1.23–1.35; p < 0.001), skipping breakfast ≥3 times/week (OR, 2.44; 95% CI, 1.35–4.41; p < 0.01), and changing from eating slowly or at medium speed to eating quickly (OR, 2.11; 95% CI, 1.04–4.26; p < 0.05). In conclusion, Japanese adults who were male, older, had a high BMI, skipped breakfast ≥3 times/week and ate quickly were at increased risk for poor glycemic control.

Association between self-reported eating speed and metabolic syndrome in a Beijing adult population: a cross-sectional study

Background

Research on the relationship between metabolic syndrome (MetS), its components and eating speed is limited in China. The present study aimed to clarify the association between MetS, its components and eating speed in a Beijing adult population.

Methods

This cross-sectional study included 7972 adults who were 18–65 years old and who received health check-ups at the Beijing Physical Examination Center in 2016. Logistic regression was conducted to explore the associations between MetS, its components and eating speed.

Results

The prevalence of MetS in this population was 24.65% (36.02% for males and 10.18% for females). Eating speed was significantly associated with a high risk for MetS, elevated blood pressure, and central obesity for both genders. Eating speed was associated with a high risk for elevated triglycerides and with a reduction in high-density lipoprotein in males, and eating speed was associated with a high risk for elevated fasting plasma glucose in females. Compared with slow eating speed, the multivariate-adjusted odds ratios of medium eating speed and fast eating speed for MetS were 1.65 (95% confidence interval 1.32–2.07) and 2.27 (95% confidence interval 1.80–2.86) for all subjects, 1.58 (95% confidence interval 1.21–2.07) and 2.21 (95% confidence interval 1.69–2.91) for males, and 1.75 (95% confidence interval 1.15–2.68) and 2.27 (95% confidence interval 1.46–3.53) for females, respectively.

Conclusions

Eating speed is positively associated with MetS and its components. Future recommendations aiming to prevent MetS and its components may focus on eating speed.

Electronic supplementary material

The online version of this article (10.1186/s12889-018-5784-z) contains supplementary material, which is available to authorized users.

Objective and Subjective Eating Speeds Are Related to Body Composition and Shape in Female College Students

Eating speed reportedly relates to body composition and shape. Little is known about the relationship between the objectively assessed eating speed and the body composition and shape. This study examined relationships between eating speed as assessed both objectively and subjectively, and body composition and shape. The following variables of body composition and shape were measured in 84 female college students: body mass, relative body fat mass (%Fat), body mass index (BMI), and circumferences of the waist, abdomen and hip. After measuring the body composition and shape, subjects consumed a 174-kcal salmon rice ball. The following chewing variables were measured by observing videotape recordings of the subjects' faces: number of chews per bite, total number of chews, total meal duration, number of bites, and chewing rate. The subjects were categorized into three groups (fast, moderate and slow) according to their own subjective assessments of the actual eating speed. In objective assessments of the eating speed, the total number of chews and the total meal duration were significantly negatively correlated with the body mass, %Fat, BMI, and circumferences of the waist, abdomen and hip. In subjective eating-speed assessments, the body mass, %Fat, BMI, and circumferences of the waist, abdomen and hip were greater in the fast eating group than in the slow eating group. Both the objectively and subjectively assessed eating speeds are related to the body composition and shape. The present study supports that fast eating may relate to gains in body mass and/or fat mass.

Associations among Obesity, Eating Speed, and Oral Health

OBJECTIVE

This study was conducted to understand how eating speed and oral health condition are associated with obesity in Japanese working men.

METHODS

We studied a total of 863 men attending an annual medical checkup of the Japanese Maritime Self Defense Force in Sasebo City, Japan. Participants answered a questionnaire about their eating speed, and we examined their anthropometric status in terms of BMI, waist circumference, and oral health condition, especially periodontal disease and number of functional teeth. Multivariate logistic regression analyses adjusting for potential confounding variables were performed.

RESULTS

The multivariate-adjusted odds ratio for waist circumference greater than 90 cm of the 'very fast' group compared to the 'slow, very slow' group was 5.22 (95% confidence interval 1.81-15.06) after adjusting for potential confounding factors. Individuals were more likely to have waist circumference greater than 90 cm if they had a larger 'number of missing functional teeth' (odds ratio 1.14; 95% confidence interval 1.01-1.28) and severe periodontal disease (odds ratio 2.74; 95% confidence interval, 1.46-5.13).

CONCLUSION

Eating speed, the number of missing functional teeth, and severe periodontal disease are associated independently with larger waist circumference.

Impact of Speed-Eating Habit on Subsequent Body Mass Index and Blood Pressure Among Schoolchildren - The Ibaraki Children's Cohort Study (IBACHIL)

BACKGROUND

Habitual speed eating is a risk factor of obesity but evidence of this in children is limited. We examined the association between speed-eating habit and subsequent body mass index (BMI) and blood pressure (BP) among Japanese children.Methods and Results:The community-based study comprised 1,490 Japanese boys and girls who were born in 1989, involved in the Ibaraki Children's Cohort Study at age 3 years, and had returned questionnaires at both ages 6 and 12 years. In a subsample, we measured BP (n=263). Speed-eating habit was categorized into 4 groups: Never, Quit, Newly, and Continuous. Sex-specific mean values of questionnaire-based BMI and measured BPs at age 12 were examined according to speed-eating habit. Children with continuous speed eating had a higher BMI at age 12 than those who had never had a speed-eating habit (20.0 vs. 17.9 kg/m²for boys (P<0.001); 20.0 vs. 18.4 kg/m²(P<0.001) for girls). Systolic BP at age 12 was higher in boys with continuous speed eating than in those without (117 vs. 110 mmHg, P=0.01), but such a difference was not observed in girls (112 vs. 111 mmHg, P=0.95).

CONCLUSIONS

Habitualspeed eating was positively associated with subsequent BMI among boys and girls as well as with systolic BP among boys.

Environmental Risk Factors for Diabetes Mellitus in Cats

Background

Diabetes in cats resembles type 2 diabetes in people. The etiology is not fully understood, but both genetic and environmental factors are believed to contribute.

Objectives

To assess the associations of environmental risk factors with diabetes in cats.

Animals

Cats with a diagnosis of diabetes (n = 396) insured by a Swedish insurance company during years 2009–2013, and a control group (n = 1,670) matched on birth year.

Methods

A web‐based questionnaire was used in a case–control study. An invitation to participate was sent to owners of 1,369 diabetic cats and 5,363 control cats. The survey contained questions related to the cat's breed, age, sex, neutering status, body condition, housing, access to the outdoors, activity level, diet, eating behavior, feeding routine, general health, stressful events, other pets in the household, medications, and vaccination status. Data were analyzed by multiple logistic regression.

Results

Response rate was 35% for the diabetic group and 32% for the control group. Indoor confinement, being a greedy eater, and being overweight were associated with an increased risk of diabetes. In cats assessed by owners as being normal weight, there was an association between eating predominantly dry food and an increased risk of diabetes (Odds ratio 3.8; 95% confidence intervals 1.3–11.2).

Conclusions and Clinical Importance

Dry food is commonly fed to cats worldwide. The association found between dry food and an increased risk of diabetes in cats assessed as normal weight by owners warrants further attention.

Lifestyle and diet in relation to risk of type 2 diabetes in Vietnam: a hospital-based case-control study

Background

Lifestyle and diet are important determinants of type 2 diabetes (T2D). Their impact on T2D can be evaluated using clinical and epidemiological approaches. Randomised controlled trials are the most rigorous design but expensive to conduct, whereas prospective cohort studies are time-consuming and less powerful for populations with a low incidence of the disease. Case–control studies are considered appropriate in resource-limited settings. A hospital-based case–control study protocol has been developed to investigate the role of lifestyle and dietary factors in T2D aetiology for adults in Vietnam.

Methods

A total of 1100 patients aged 40–65 years (550 T2D cases and 550 controls) will be recruited from a tertiary hospital in Hanoi, the capital city of Vietnam. Cases and controls will be frequency-matched on age (±3 years), gender, and residential location. T2D will be diagnosed according to the 2006 World Health Organisation criteria. Habitual physical activity will be assessed by the Vietnamese version of the International Physical Activity Questionnaire-Short Form. Food and beverage consumption will be ascertained using a Validated Food Frequency Questionnaire, specifically developed for the Vietnamese population. Information on demographic and other personal characteristics will be collected, together with anthropometric and blood pressure measurements. Descriptive statistics and unconditional logistic regression analyses will be performed to examine factors associated with the T2D prevalence.

Discussion

The proposed study will elucidate the role of lifestyle and diet in T2D prevalence among Vietnamese adults. Findings concerning pertinent factors will provide epidemiological evidence for the development of focused interventions, and contribute to the formulation of national policies to prevent and control T2D in Vietnam.

Association between eating speed and metabolic syndrome in a three-year population-based cohort study

Background

Metabolic syndrome has received increased global attention over the past few years. Eating behaviors, particularly eating speed, have long been of interest as factors that contribute to the development of obesity and diabetes. The aim of this study was to assess the relationship between eating speed and incidence of metabolic syndrome among middle-aged and elderly Japanese people.

Methods

A total of 8941 community residents from Soka City in Saitama Prefecture, aged from 40 to 75 years and without a diagnosis of metabolic syndrome, participated in the baseline survey in 2008 and were followed until 2011. Anthropometric measurements and lifestyle factors were measured at baseline and follow-up. The association between eating speed and incidence of metabolic syndrome was evaluated using Cox proportional hazards models adjusted for potential confounding variables.

Results

During the 3-year follow-up, 647 people were diagnosed with metabolic syndrome (25.0 cases/1000 person-years). The incidence rates of metabolic syndrome among non-fast-eating and fast-eating participants were 2.3% and 3.1%, respectively. The multivariate-adjusted hazard ratio for incidence of metabolic syndrome in the fast-eating group compared to the not-fast-eating group was 1.30 (95% confidence interval [CI], 1.05–1.60) after adjustment for the potential confounding factors. Eating speed was significantly correlated with waist circumference and high-density lipoprotein cholesterol (HDL-C) components of metabolic risk factors. Hazard ratios in the fast-eating group compared with the reference group were 1.35 (95% CI, 1.10–1.66) for waist circumference and 1.37 (95% CI, 1.12–1.67) for HDL-C.

Conclusions

Eating speed was associated with the incidence of metabolic syndrome. Eating slowly is therefore suggested to be an important lifestyle factor for preventing metabolic syndrome among the Japanese.

Self-reported eating rate and metabolic syndrome in Japanese people: cross-sectional study

OBJECTIVES

To examine the association between self-reported eating rate and metabolic syndrome.

DESIGN

Cross-sectional study.

SETTING

Annual health checkup at a health check service centre in Japan.

PARTICIPANTS

A total of 56,865 participants (41,820 male and 15,045 female) who attended a health checkup in 2011 and reported no history of coronary heart disease or stroke.

MAIN OUTCOME MEASURE

Metabolic syndrome was defined by the joint of interim statement of the International Diabetes Federation and the American Heart Association/National Heart, Lung, and Blood Institute.

RESULTS

In multiple logistic regression models, eating rate was significantly and positively associated with metabolic syndrome. The multivariable-adjusted ORs (95% CI) for slow, normal and fast were 0.70 (0.62 to 0.79), 1.00 (reference) and 1.61 (1.53 to 1.70), respectively, in men (p for trend <0.001), and 0.74 (0.60 to 0.91), 1.00 (reference) and 1.27 (1.13 to 1.43), respectively, in women (p for trend <0.001). Of metabolic syndrome components, abdominal obesity showed the strongest association with eating rate. The associations of eating rate and metabolic syndrome and its components were largely attenuated after further adjustment for body mass index; however, the association of slow eating with lower odds of high blood pressure (men and women) and hyperglycaemia (men) and that of fast eating with higher odds of lipid abnormality (men) remained statistically significant.

CONCLUSIONS

Results suggest that eating rate is associated with the presence of metabolic syndrome and that this association is largely accounted for by the difference in body mass according to eating rate.