The dose-response relationship of fruit and vegetable intake and risk of type 2 diabetes among rural China: The Henan Rural Cohort study.

AIMS: To explore the dose-response relationship of fruit and vegetable (F&V) intake and type 2 diabetes (T2D) risk in rural China. METHODS: A total of 38798 adults were recruited from the Henan Rural Cohort Study. F&V intake was assessed by a validated food-frequency questionnaire. Logistic regression and restricted cubic splines analysis were conducted to calculate the odds ratio (OR) for T2D relative to F&V intake and investigate the dose-response relationship. RESULTS: Higher intake of fruit or combined F&V was in connection with a lower risk of T2D, after adjusting for multiple confounders. After analyzing the dose-response relationship, we found that the odds of T2D decreased significantly with fruit consumption ≥ 260 g/day or F&V intake between 600 and 1000 g/day. And in subgroup analysis, we found that the negative correlation between fruit consumption and T2D was more pronounced in non-current smokers and non-current drinkers. CONCLUSIONS: High intake of fruit alone or combined F&V is related to a reduced risk of T2D in rural China. Fruit intake ≥ 260 g/day and total F&V consumption of 600-1000 g/day should be encouraged to promote good health.

Association of intestinal microbiota markers and dietary pattern in Chinese patients with type 2 diabetes: The Henan rural cohort study.

Studies on intestinal microbiota in Chinese type 2 diabetes mellitus (T2DM) patients are scarce and correlation studies with dietary intake are lacking. The case-control study included 150 participants (74 T2DM patients and 76 controls) and microbiome analysis was performed using 16S rDNA sequencing. Principal component analysis was used to determine dietary patterns and correlation analysis was used to evaluate the associations between microbiota diversity, T2DM indicators and dietary variables. Compared to controls, the T2DM group had different gut flora characteristics, including lower alpha diversity, higher Firmicutes/Bacteroidetes ratios, statistically significant beta diversity and other specific bacterial species differences. Gut microbiota was associated with several diabetes-related metabolic markers including HOMA2-ß, fasting plasma glucose, HbA1c and fasting insulin. Significant associations were also observed between dietary intake pattern and gut flora. The animal foods pattern scores were positively correlated with the relative abundance of the phylum Fusobacteria, and the vegetarian diet pattern scores were positively correlated with the relative abundance of the phylum Actinobacteria. Phylum Actinobacteria mediated the association of vegetarian diet pattern with fasting insulin and HOMA2-ß (all P < 0.05). Composition of intestinal microbiota in Chinese T2DM patients differs from that of control population, and the intestinal flora is affected by dietary intake while being associated with several diabetes-related metabolic markers. The gut microbiota may play an important role in linking dietary intake and the etiology of T2DM.

Association between Dietary Protein Intake and Type 2 Diabetes Mellitus in Chinese Rural Elderly Population: A Matched Case-Control Study.

The purpose of this study was to examine the association between dietary protein intake and the risk of type 2 diabetes mellitus (T2DM) among a Chinese rural elderly population. We used the demographic and dietary information of adults over age 65 in the Henan Rural Cohort Study to identify and pair 950 T2DM patients with healthy controls in a 1 : 1 matched case-control study. Dietary data was collected through a Food Frequency Questionnaire. A multivariate logistic regression model was applied to calculate the odds ratio (OR) and 95% confidence interval (CI) of T2DM risk according to protein intake. After adjustment for confounding factors, higher intake of total protein was negatively associated with T2DM risk in the total population (extreme-tertile OR=0.75, 95% CI: 0.58-0.93) and women (extreme-tertile OR=0.84, 95% CI: 0.47-0.93). Multivariate-adjusted ORs for the risk of T2DM in the highest compared with lowest tertile of plant protein intake in the total population and in women were 0.86 (95% CI: 0.60-0.84) and 0.58 (95% CI: 0.36-0.95), respectively. Our results suggest that the protein intake, especially plant protein, has a significant association with the risk of T2DM in rural elderly populations, and the sources of protein may be also important in future guidelines.

Association of sleep duration with risk of type 2 diabetes mellitus in a rural Chinese population: a nested case-control study.

PURPOSE: To investigate the association of sleep duration with type 2 diabetes mellitus (T2DM) in a rural Chinese population. METHODS: A 1:1 matched nested case-control study was performed based on a cohort that had been established in rural communities in Henan Province, China. T2DM patients and healthy controls (550 pairs) were included in this study. RESULTS: Abnormal sleep duration significantly increased the risk of T2DM with an approximate U-shaped association (sleep duration ≤ 6 h, OR = 1.742, 95% CI = 1.007-3.011, P = 0.047; sleep duration 8-9 h, OR = 1.462, 95% CI = 1.038-2.060, P = 0.030) compared with participants with a night sleep duration of 7-8 h, after adjusting for multiple confounders. When stratified by gender, only women were sensitive to shorter sleep duration (OR = 2.483, 95% CI = 1.149-5.366, P = 0.021). Abnormal sleep duration (too short or too long) had adverse effects on homeostasis model assessment (HOMA) and blood metabolites, and the effect was more noticeable in people with longer sleep durations. CONCLUSION: In a rural Chinese population, both too short and too long sleep duration increased the risk of T2DM. Especially women with less sleep duration have a higher risk of T2DM. Abnormal sleep also affects the HOMA index and metabolites; the relationship between HOMA-IR, total cholesterol, and LDL-Cholesterol with sleep duration was U-shaped, while fasting plasma glucose, body mass index, waist circumference, and triglyceride levels increased significantly only with longer sleep duration.

Association of plant-based diet and type 2 diabetes mellitus in Chinese rural adults: The Henan Rural Cohort Study.

AIMS/INTRODUCTION: Studies have found that a plant-based diet was associated with a lower risk of type 2 diabetes, but evidence is scarce on such associations in China. The aim of this study was to investigate whether a plant-based diet is related to a lower risk of type 2 diabetes among Chinese adults. MATERIALS AND METHODS: A total of 37,985 participants were enrolled from the Henan Rural Cohort Study. An overall plant-based diet index (PDI) was created by assigning positive and reverse scores to 12 commonly consumed food groups. Multivariate logistic regression models and restricted cubic spline analysis were performed to estimate the odds ratio (OR) and 95% confidence interval (95% CI). RESULTS: After multivariable adjustment, the risk of type 2 diabetes was inversely associated with the PDI (extreme-quartile OR = 0.88, 95% CI: 0.79-0.98; P = 0.027), the risk associated with a 1 standard deviation (SD) increase in PDI was 4% lower (95% CI, 0.93-1.00; P trend  = 0.043) for type 2 diabetes. Moreover, the odds of type 2 diabetes was decreased with an increment of PDI after fitting restricted cubic splines (P trend  < 0.01). CONCLUSIONS: Among Chinese populations, diets higher in plant foods and lower in animal foods were associated with a reduced risk of type 2 diabetes.

Consumption of Dairy Products in Relation to Type 2 Diabetes Mellitus in Chinese People: The Henan Rural Cohort Study and an Updated Meta-Analysis.

Recent studies on whether dairy consumption is associated with type 2 diabetes mellitus (T2DM) have yielded inconsistent results, so we explored the relationship between dairy consumption and T2DM through a large-sample, cross-sectional study and a meta-analysis. In the meta-analysis, summary relative risks (RRs) of 23 articles were compiled with a random effects model, and a restricted cubic spline regression model was used to explore whether there is a nonlinear relationship between dairy intake and T2DM risk. This cross-sectional study used baseline data from 38,735 participants of the Henan Rural Cohort study and the association between dairy consumption and T2DM was analyzed by a logistic regression model. The meta-analysis revealed a borderline negative significant association between total dairy intake and risk of T2DM, the RR and 95% confidence interval (CI) was 0.94; (0.89, 1.00), and the risk was lowest at 270 g daily dairy intake. In the cross-sectional study, there were 3654 T2DM patients and 68.3 percent of the respondents had no dairy intake. The average intake of dairy in the total population was 12 g per day. Fully adjusted analyses suggested positive associations, with an odds ratio (OR) comparing the highest with the zero intake of 1.34 (95% CI: 1.22, 1.48) for all participants, which was unaffected by sex. Dairy intake in rural areas of Henan province is low, and we found, in the context of overall low dairy intake, that a high intake was positively associated with T2DM, which is inconsistent with the meta-analysis results suggesting that dairy has marginal protective effects against T2DM.

Age at menopause, body mass index, and risk of type 2 diabetes mellitus in postmenopausal Chinese women: The Henan Rural Cohort study.

BACKGROUND AND AIM: The present study was conducted to explore the stratified and joint effects of age at menopause and body mass index (BMI) with the risk of type 2 diabetes mellitus (T2DM) in Chinese rural adults. METHODS AND RESULTS: A total of 15,406 postmenopausal Chinese women were included in this study. Multivariable logistic regression analysis was used to quantify the stratified and joint effects of age at menopause and BMI on T2DM. Overall, the mean age at menopause and BMI was 48.8 ± 4.7 years and 25.1 ± 3.6 kg/m2, respectively. In general, data suggest that: 1) women with BMI ≥ 24 had a higher risk of T2DM, irrespective of age at menopause; 2) in women with BMI < 24, later menopause had a higher risk of T2DM (OR, 1.52; 95% CI, 1.16-2.01); 3) the risk of T2DM was higher only in patients with early or normal age at menopause and BMI ≥ 24, with 0R (95% CI) of (1.58, 1.28-1.94) and (1.48, 1.31-1.67), respectively. CONCLUSION: Our findings suggest that: 1) women with BMI ≥ 24 had a higher risk of T2DM, irrespective of age at menopause; 2) in women with BMI < 24, a higher risk of T2DM was found only in those with later menopause; 3) women with later menopause had a higher risk of T2DM, irrespective of BMI; 4) in patients with early or normal age at menopause, a higher risk of T2DM was found only in patients with BMI ≥ 24. THE CHINESE CLINICAL TRIAL REGISTRATION: ChiCTR-OOC-1500669(URL:http://www.chictr.org.cn/showproj.aspx?proj=11375).

Meat and fish intake and type 2 diabetes: Dose-response meta-analysis of prospective cohort studies.

AIMS: This meta-analysis aimed to quantitatively examine the possible associations between total meat, red meat, processed meat, poultry and fish intakes and type 2 diabetes (T2D). METHODS: Relevant articles were identified in PubMed, Embase and Web of Science databases using a search time up to January 2019. Generalized least-squares trend estimations and restricted cubic spline regression models were used for analysis. RESULTS: Twenty-eight articles were included in the analysis. When comparing the highest with the lowest category of meat intake, the summary relative risk of T2D was 1.33 (95% CI: 1.16-1.52) for total meat, 1.22 (95% CI: 1.16-1.28) for red meat, 1.25 (95% CI: 1.13-1.37) for processed meat, 1.00 (95% CI: 0.93-1.07) for poultry and 1.01 (95% CI: 0.93-1.10) for fish. In the dose-response analysis, each additional 100g/day of total and red meat, and 50g/day of processed meat, were found to be associated with a 36% (95% CI: 1.23-1.49), 31% (95% CI: 1.19-1.45) and 46% (95% CI: 1.26-1.69) increased risk of T2D, respectively. In addition, there was evidence of a non-linear dose-response association between processed meat and T2D (P=0.004), with the risk increasing by 30% with increasing intakes up to 30g/day. CONCLUSION: Our meta-analysis has shown a linear dose-response relationship between total meat, red meat and processed meat intakes and T2D risk. In addition, a non-linear relationship of intake of processed meat with risk of T2D was detected.

Dietary Protein Consumption and the Risk of Type 2 Diabetes: ADose-Response Meta-Analysis of Prospective Studies.

The relationship between dietary protein consumption and the risk of type 2 diabetes (T2D) has been inconsistent. The aim of this meta-analysis was to explore the relations between dietary protein consumption and the risk of T2D. We conducted systematic retrieval of prospective studies in PubMed, Embase, and Web of Science. Summary relative risks were compiled with a fixed effects model or a random effects model, and a restricted cubic spline regression model and generalized least squares analysis were used to evaluate the diet-T2D incidence relationship. T2D risk increased with increasing consumption of total protein and animal protein, red meat, processed meat, milk, and eggs, respectively, while plant protein and yogurt had an inverse relationship. A non-linear association with the risk for T2D was found for the consumption of plant protein, processed meat, milk, yogurt, and soy. This meta-analysis suggests that substitution of plant protein and yogurt for animal protein, especially red meat and processed meat, can reduce the risk for T2D.