Vegetable and fruit intake and risk of type 2 diabetes: Japan Public Health Center-based Prospective Study

The Interactive Effects of Fruit Intake Frequency and Serum miR-484 Levels as Biomarkers for Incident Type 2 Diabetes in a Prospective Cohort of the Spanish Adult Population: The Di@bet.es Study

Background/Objectives: Although evidence suggests that miR-484 and several fruit components are involved in glucose metabolism and insulin resistance metabolic pathways, the relationship between serum miR-484 levels and fruit consumption in relation to the risk of Type 2 diabetes (T2DM) remains elusive. The aim of this study was to evaluate the possible association between serum miR-484 levels and fruit intake frequency with the risk of T2DM in the Spanish adult population. Methods: 2234 subjects from the Di@bet.es cohort study without T2DM at baseline were studied. Socio-demographic, anthropometric and clinical data were recorded, as well as responses to a questionnaire on habits, including frequency of fruit consumption (daily vs. occasional). T2DM was diagnosed at baseline and after 7.5 years of follow-up. Baseline serum miR-484 levels were measured using real-time qPCR and categorized based on the 25th percentile. Association analyses were performed using logistic regression models adjusted for potential confounders. Interaction effects were evaluated on the multiplicative and additive scales. Results: There was no association between miR-484 levels and fruit intake frequency. Categorized miR-484 levels and fruit consumption were inversely and independently associated with the likelihood of incident T2DM. Analysis of the interaction effect suggests the presence of both positive multiplicative and additive interactions between miR-484 categories and fruit consumption frequency. Conclusions: Our study demonstrates a protective effect of daily fruit intake and high miR-484 levels regarding the risk of T2DM and supports the nutritional recommendations advocating daily fruit consumption. This study also suggests that the combined effect of low miR-484 levels and occasional fruit intake may increase the risk of T2DM beyond their independent effects.

Suboptimal diet quality is associated with the incidence of type 2 diabetes mellitus in middle-aged and older populations in China: evidence from a population-based cross-sectional study

The association between dietary quality and type 2 diabetes mellitus (T2DM) based on the Chinese Dietary Balance Index (DBI-16) is seldom reported. We hypothesized that poor dietary quality might increase the risk of T2DM in the middle-aged and older populations. A total of 1816 individuals (≥50 years) were included in the study. Demographic characteristics and dietary intake data were collected. Logistic regression and restricted cubic spline (RCS) analyses were conducted to explore the association between DBI-16 indexes and the risk of T2DM. The insufficient intake of vegetables and dairy might decrease the risk of T2DM (ORVegetable = 0.77, 95% CI = 0.60-0.97; ORDairy = 0.58, 95% CI = 0.35-0.96), but the individuals with insufficient intake of fruit were more likely to have a higher risk of T2DM (ORfruit = 2.26, 95% CI = 1.69-3.06). Compared with the subjects with the lowest quartile of Low Bound Score (LBS) or Diet Quality Distance (DQD), the individuals with Q2 and Q3 level of LBS (ORQ2 = 1.40, 95% CI = 1.03-1.90, P = .033; ORQ3 = 1.52, 95% CI = 1.11-2.08, P < .01) or DQD (ORQ2 = 1.45, 95% CI = 1.06-1.99, P = .021; ORQ3 = 1.64, 95% CI = 1.20-2.24, P < .01) showed increased risk of T2DM with a nonlinear association observed by RCS analysis. We concluded that imbalanced dietary intake, especially insufficient daily fruit intake, might predict an increased risk of T2DM in the middle-aged and elderly Chinese.

Prospective association between fruit and vegetable intake and the risk of type 2 diabetes amongst Chinese adults: the China Health and Nutrition Survey

This study aimed to prospectively explore the relationship between fruit and vegetable intake (FVI) and type 2 diabetes (T2D) risk amongst 13,175 Chinese adults. Cox proportional hazards models were used to estimate the hazard ratios (HRs) of T2D events in relation to FVI. Results showed that the highest quintile of FVI was inversely associated with T2D risk in men (HR = 0.72, 95% CI: 0.50, 0.98) and women (HR = 0.74, 95% CI: 0.55, 0.97), whereas no such associations were observed between total vegetable intake and T2D in either men (HR = 0.92, 95% CI: 0.65, 1.26) or women (HR = 1.02, 95% CI: 0.77, 1.38). In addition, greater fruit intake was inversely associated with T2D risk in men (HR = 0.42, 95% CI: 0.28, 0.63) and women (HR = 0.64, 95% CI: 0.45, 0.90). Overall, FVI and total fruit intake were inversely associated with T2D risk amongst Chinese adults.

Health effects associated with vegetable consumption: a Burden of Proof study

Previous research suggests a protective effect of vegetable consumption against chronic disease, but the quality of evidence underlying those findings remains uncertain. We applied a Bayesian meta-regression tool to estimate the mean risk function and quantify the quality of evidence for associations between vegetable consumption and ischemic heart disease (IHD), ischemic stroke, hemorrhagic stroke, type 2 diabetes and esophageal cancer. Increasing from no vegetable consumption to the theoretical minimum risk exposure level (306-372 g daily) was associated with a 23.2% decline (95% uncertainty interval, including between-study heterogeneity: 16.4-29.4) in ischemic stroke risk; a 22.9% (13.6-31.3) decline in IHD risk; a 15.9% (1.7-28.1) decline in hemorrhagic stroke risk; a 28.5% (-0.02-51.4) decline in esophageal cancer risk; and a 26.1% (-3.6-48.3) decline in type 2 diabetes risk. We found statistically significant protective effects of vegetable consumption for ischemic stroke (three stars), IHD (two stars), hemorrhagic stroke (two stars) and esophageal cancer (two stars). Including between-study heterogeneity, we did not detect a significant association with type 2 diabetes, corresponding to a one-star rating. Although current evidence supports increased efforts and policies to promote vegetable consumption, remaining uncertainties suggest the need for continued research.

Fruit and vegetable intake and risk of prediabetes and type 2 diabetes: results from a 20-year long prospective cohort study in Swedish men and women

Purpose

To investigate the association between fruit and vegetable intake (FVI) and the risk of developing prediabetes and type 2 diabetes (T2D) in a Swedish prospective cohort study.

Methods

Subjects were 6961 men and women aged 35–56 years old at baseline, participating in the Stockholm Diabetes Prevention Program cohort. By design, the cohort was enriched by 50% with subjects that had family history of diabetes. Anthropometric measurements, oral glucose tolerance tests and questionnaires on lifestyle and dietary factors were carried out at baseline and two follow-up occasions. Cox proportional hazard models were used to estimate hazard ratios with 95% CIs.

Results

During a mean follow-up time of 20 ± 4 years, 1024 subjects developed T2D and 870 prediabetes. After adjustments for confounders, the highest tertile of total FVI was associated with a lower risk of developing T2D in men (HR 0.76, 95% CI 0.60–0.96). There was also an inverse association between total fruit intake and prediabetes risk in men, with the HR for the highest tertile being 0.76 (95% CI 0.58–1.00). As for subtypes, higher intake of apples/pears was inversely associated with T2D risk in both sexes, whereas higher intakes of banana, cabbage and tomato were positively associated with T2D or prediabetes risk in either men or women.

Conclusion

We found an inverse association between higher total FVI and T2D risk and between higher fruit intake and prediabetes risk, in men but not in women. Certain fruit and vegetable subtypes showed varying results and require further investigation.

Supplementary Information

The online version contains supplementary material available at 10.1007/s00394-022-02871-6.

Fruit and vegetable consumption and the risk of type 2 diabetes: a systematic review and dose-response meta-analysis of prospective studies

BACKGROUND

The association between intake of fruit and vegetables and their subtypes, and the risk of type 2 diabetes has been investigated in several studies, but the results have been inconsistent.

OBJECTIVE

We conducted an updated systematic review and dose-response meta-analysis of prospective studies on intakes of fruit and vegetables and fruit and vegetable subtypes and the risk of type 2 diabetes.

DESIGN

PubMed and Embase databases were searched up to 20 October 2020. Prospective cohort studies of fruit and vegetable consumption and type 2 diabetes mellitus were included. Summary relative risks (RRs) and 95% CIs were estimated using a random effects model.

RESULTS

We included 23 cohort studies. The summary RR for high versus low intake and per 200 g/day were 0.93 (95% CI: 0.89 to 0.98, I²=0%, n=10 studies) and 0.98 (95% CI: 0.95 to 1.01, I²=37.8%, n=7) for fruit and vegetables combined, 0.93 (95% CI: 0.90 to 0.97, I²=9.3%, n=20) and 0.96 (95% CI: 0.92 to 1.00, I²=68.4%, n=19) for fruits and 0.95 (95% CI: 0.88 to 1.02, I²=60.4%, n=17) and 0.97 (95% CI: 0.94 to 1.01, I²=39.2%, n=16) for vegetables, respectively. Inverse associations were observed for apples, apples and pears, blueberries, grapefruit and grapes and raisins, while positive associations were observed for intakes of cantaloupe, fruit drinks, fruit juice, brussels sprouts, cauliflower and potatoes, however, most of these associations were based on few studies and need further investigation in additional studies.

CONCLUSIONS

This meta-analysis found a weak inverse association between fruit and vegetable intake and type 2 diabetes risk. There is indication of both inverse and positive associations between intake of several fruit and vegetables subtypes and type 2 diabetes risk, however, further studies are needed before firm conclusions can be made.

Branched-chain amino acid synthesis and glucosinolate-myrosinase system during takuan-zuke processing of radish root

The traditional Japanese fermented pickle, takuan-zuke, is produced via dehydration and salt-aging of the Japanese winter radish root (Raphanus sativus L.). It has been reported that γ-aminobutyric acid (GABA; antihypertensive factor) accumulates during this production. Herein, the results of the comprehensive study (metabolites, enzyme activity, and gene expression levels were investigated) on the mechanism of branched-chain amino acid (BCAA) synthesis and glucosinolate (GLS)-myrosinase system of daikon dehydration have been reported. BCAAs, GLS, and their precursors were temporarily upregulated, and the genes linked to BCAA, GLS, and isothiocyanate synthesis (BCAT4, MAM3, IPMDH1, RMB1, RMB2, and GRS1) were upregulated during daikon dehydration. BCAAs and GLS accumulated in daikon during dehydration owing to the upregulation of genes, encoding these synthases as a stress response. These results suggest that the biological response of daikon adds characteristic flavor and health functionality to takuan-zuke and helps optimize the processing parameters to produce pickles with improved health benefits. PRACTICAL APPLICATIONS: Takuan-zuke is a popular pickle in Japan, which is produced from a Japanese winter radish root (Raphanus sativus L.), commonly referred to as daikon in Japan. Takuan-zuke is produced by dehydrating daikon either by the process of salt-pressing (shio-oshi) or sun-drying (hoshi). The processes influence the variations in the nutritional value of the final product. The results reveal that both the daikon dehydration processes can be followed to generate increased amounts of health-promoting components (e.g., branched-chain amino acid and glucosinolate) in takuan-zuke.

Cabbage (Brassica oleracea var. capitata): A food with functional properties aimed to type 2 diabetes prevention and management

Type 2 diabetes mellitus (T2DM) is increasing the prevalence worldwide at an alarming rate, becoming a serious public health problem that mainly affects developing countries. Functional food research is currently of great interest because it contributes to developing nutritional therapy strategies for T2DM prevention and treatment. Bioactive compounds identified in some plant foods contribute to human health by mechanisms of action that exert biological effects on metabolic pathways involved in the development of T2DM. Hence, vegetables with high bioactive compounds content may be a source of functional value for the control of T2DM. Cabbages varieties (Brassica oleracea var. capitata) such as green (GCB), white (WCB), and red (RCB) are foods consumed (raw or cooked) and cultivated in different regions of the world. Scientific evidence shows that cabbage has multi-target effects on glucose homeostatic regulation due to its high content of bioactive compounds. It has also been shown to decrease damage to organs affected by T2DM complications, such as the liver and kidney. Additionally, it could contribute as a preventive by attenuating problems underlying the development of T2DM as oxidative stress and obesity. This review highlights the functional properties of cabbage varieties involved in glucose regulation and the main mechanisms of the action exerted by their bioactive compounds. In conclusion, cabbage is a valuable food that can be employed as part of nutritional therapy or functional ingredient aimed at the prevention and treatment of T2DM.

Specific fruit but not total fruit intake during early pregnancy is inversely associated with gestational diabetes mellitus risk: a prospective cohort study

OBJECTIVES

Fruit intake may influence gestational diabetes mellitus (GDM) risk. However, prospective evidence remains controversial and limited. The current study aimed to investigate whether total fruit and specific fruit intake influence GDM risk.

DESIGN

A prospective cohort study was conducted. Dietary information was collected by a 3-d 24-h dietary recall. All participants underwent a standard 75-g oral glucose tolerance test at 24-28 gestational weeks. Log-binomial models were used to estimate the association between fruit intake and GDM risk, and the results are presented as relative risks (RR) and 95 % CI.

SETTING

Southwest China.

PARTICIPANTS

Totally, 1453 healthy pregnant women in 2017.

RESULTS

Total fruit intake was not associated with lower GDM risk (RR of 1·03 (95 % CI 0·83, 1·27) (Ptrend = 0·789)). The RR of GDM risk was 0·73 for the highest anthocyanin-rich fruit intake quartile compared with the lowest quartile (95 % CI 0·56, 0·93; Ptrend = 0·015). A higher grape intake had a linear inverse association with GDM risk (Q4 v. Q1: RR = 0·65; 95 % CI 0·43, 0·98; Ptrend = 0·044), and after further adjustment for anthocyanin intake, the inverse association tended to be non-linear (Q4 v. Q1: RR = 0·65; 95 % CI 0·44, 0·98; Ptrend = 0·079). However, we did not find an association between glycaemic index-grouped fruit, glycaemic load-grouped fruit or other fruit subtype intake and GDM risk.

CONCLUSIONS

In conclusion, specific fruit intake (particularly anthocyanin-rich fruit and grapes) but not total fruit intake was inversely associated with GDM risk.

Fruit Intake and Changes of Cardio-Metabolic Risk Factors in People with Obesity

BACKGROUND

This study aimed to explore the relationship between fruit intake, changes in fruit intake, and changes in cardiometabolic factors in people with obesity.

METHODS

A total of 21,270 subjects (8,718 men, 12,552 women) aged 40 years and over, from the Korean-based Genome and Epidemiology Study, were followed up for an average of 4.4 years. Fruit intake was assessed using a food frequency questionnaire at baseline and the second follow-up. The beta coefficient and confidence intervals for changes in cardiometabolic risk factors according to fruit consumption were calculated using a linear regression model.

RESULTS

In men, the abdominal circumference decreased with changes in fruit intake (P=0.029). Fruit intake and increased fruit intake in men were associated with a lower systolic blood pressure (P=0.012 and P=0.02, respectively) and lower triglyceride levels (P=0.002 and P<0.001, respectively). In women, abdominal circumference decreased with both fruit intake and increased fruit intake (P<0.001 and P=0.013, respectively). Systolic blood pressure and triglycerides tended to decrease only with fruit intake (P=0.048 and P<0.001, respectively). Unlike in men, fasting blood glucose tended to decrease in women with both fruit intake and increased fruit intake (P=0.011 and P=0.005, respectively).

CONCLUSION

Fruit intake and increased fruit intake may have beneficial effects on cardiometabolic risk factors among individuals who are obese.

Prediction of disability-adjusted life years for diseases due to low fruit intake in 2017-2040 in Japan

OBJECTIVE

The current study aimed to predict disability-adjusted life years (DALY) rate in Japan through 2040 with plausible future scenarios of fruit intake for neoplasms, cardiovascular diseases (CVD) and diabetes and kidney diseases (DKD).

DESIGN

Data from National Health and Nutrition Surveys and the Global Burden of Diseases study in 2017 were used. We developed an autoregressive integrated moving average model with four future scenarios. Reference scenario maintains the current trend. Best scenario assumes that the goal defined in Health Japan 21 is achieved in 2023 and is kept constant afterwards. Moderate scenario assumes that the goal is achieved in 2040. Constant scenario applies the same proportion of 2016 for the period between 2017 and 2040.

SETTING

DALY rates in Japan were predicted for the period between 2017 and 2040.

PARTICIPANTS

Population aged more than than 20 years old.

RESULTS

In our reference forecast, the DALY rates in all-ages group were projected to be stable for CVD and continue increasing for neoplasms and DKD. Age group-specific DALY rates for these three disease groups were forecasted to decrease, with some exceptions. Among men aged 20-49 years, DALY attributable to CVD differed substantially between the scenarios, implying that there is a significant potential for reducing the burden of CVD by increasing fruit intake at the population level.

CONCLUSIONS

Our scenario analysis shows that higher fruit intake is associated with lower disease burden in Japan. Further research is required to assess which policies and interventions can be used to achieve an increase in fruit intake as modelled in the scenarios of the current study.

Projections of disability-adjusted life years for major diseases due to a change in vegetable intake in 2017-2040 in Japan

Background

Low vegetable intake is one of the key dietary risk factors known to be associated with a range of health problems, including cardiovascular diseases (CVDs), cancer, and diabetes and kidney diseases (DKDs). Using data from Japan’s National Health and Nutrition Surveys and the Global Burden of Diseases study in 2017, this study aimed to forecast the impact of change in vegetable intake on disability-adjusted life years (DALYs) between 2017 and 2040 for three diseases.

Methods

We generated a three-component model of cause-specific DALYs, including changes in major behavioural and metabolic risk predictors, the socio-demographic index and an autoregressive integrated moving average model to project future DALY rates for 2017–2040 using the data between 1990 and 2016. Data on Vegetable consumption and risk predictors, and DALY rate were obtained from Japan’s National Health and Nutrition Surveys and the Global Burden of Diseases Study in 2017. We also modelled three scenarios of better, moderate and worse cases to evaluate the impact of change in vegetable consumption on the DALY rates for three diseases (CVDs, cancer, and DKDs).

Results

Projected mean vegetable intake in the total population showed a decreasing trend through 2040 to 237.7 g/day. A significant difference between the reference scenario and the better case scenario was observed with un-overlapped 95% prediction intervals of DALY rates in females aged 20–49 years (− 8.0%) for CVDs, the total population for cancer (− 5.6%), and in males (− 8.2%) and females (− 13.7%) for DKDs.

Conclusions

Our analysis indicates that increased vegetable consumption would have a significant reduction in the burdens of CVDs, cancer and DKDs in Japan. By estimating the disease burden attributable to low vegetable intake under different scenarios of future vegetable consumption, our study can inform the design of targeted interventions for public health challenges.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12889-021-10772-2.

Does the association between patterns of fruit and vegetables and metabolic syndrome incidence vary according to lifestyle factors and socioeconomic status?

BACKGROUND AND AIMS

The aim of this study is to investigate the association between the identified patterns of fruits and vegetables and metabolic syndrome (MetS) incidence, and to investigate whether lifestyle factors and socioeconomic status modify the effect of the patterns on MetS risk.

METHODS AND RESULTS

We prospectively studied 1915 participants of the Tehran Lipid and Glucose Study, who were aged 19-74 years and followed up for dietary assessment using a validated, semi-quantitative food frequency questionnaire. After adjustment for confounding factors, total vegetable intake was inversely related to the risk of MetS. Total fruit and total fruit and vegetable were not associated with MetS risk. We identified four major patterns of fruits and vegetables by factor analysis: "fresh fruit pattern", "vegetable pattern", "dried fruit and cruciferous vegetable pattern", and "potatoes and fruit juice pattern". "Vegetable pattern" was negatively associated with MetS risk, and "potatoes and fruit juice pattern" increased the risk of MetS. Among participants with weight gain <7% during follow-up, all four identified patterns reduced MetS risk. When stratified by smoking, "vegetable pattern" and "dried Fruit and cruciferous vegetable pattern" lowered MetS risk among non-smokers. Stratification based on education resulted in MetS risk reduction across tertiles of "fresh fruit pattern" and "vegetable pattern". First and second tertiles of "dried fruit and cruciferous vegetable pattern" lowered MetS risk among educated participants, compared to the reference.

CONCLUSIONS

The reduction in MetS risk caused by fruits and vegetables intake depends on the modifying effect of lifestyle and socioeconomic factors.

Fruit and vegetable intake is inversely associated with type 2 diabetes in Chinese women: results from the China Health and Nutrition Survey

This study aimed to evaluate the associations between fruit and vegetable (FV) intake and the risk of prediabetes or type 2 diabetes (T2D). It is a cross-sectional study that involved 6802 participants aged 18-65 years. Dietary intake and other variables were assessed by questionnaires. The prevalence of prediabetes and T2D was ascertained by self-report and analyses of fasting blood samples. In the multiple logistic regression models, FV intake was negatively associated the risk of T2D in women (OR = 0.45, 95% CI: 0.28, 0.71), whereas no such association was observed in men (OR = 0.98, 95% CI: 0.65, 1.47). Furthermore, FV consumption was inversely associated with prediabetes risk in men and women. Results suggested that higher intake of FV was associated with a decreased risk of T2D or prediabetes in Chinese women and a reduced risk of prediabetes in men only.

Consumption of fruit and vegetables and the risk of type 2 diabetes: a 4-year longitudinal study among Swedish adults

A low intake of fruit and vegetables is a significant contributor to the global burden of disease. The aim of this study was to estimate the size of the risk of type 2 diabetes (T2D) of a low intake and to investigate possible sex differences. In this regard, this study used a longitudinal data from the Stockholm Public Health Cohort located in Sweden, collected in 2010 and 2014. The analysis included 14 718 men and 20 589 women aged 25 to 84 years. Fruit and vegetable intake, separately <2 servings/d or combined <4 servings/d (one serving corresponding to 100 g) was set as a cut-point for low intake. The sex difference at baseline was examined. Sex-stratified logistic regression was performed with onset of T2D as the outcome and fruit and vegetable intake at baseline as the exposure with adjustment for other known risk factors. Results indicate that men consumed significantly (P < 0⋅001) less fruit and vegetables compared with women. A 62 % higher risk to develop T2D over the 4-year period was observed in men who had low vegetable intake compared with high intake after adjusting for age, education, BMI, smoking, alcohol and physical activity (OR 1⋅62; 95 % CI 1⋅00, 2⋅63). In women, a significantly higher risk of T2D was also observed with a low intake of vegetables, but not after adjustment. The present study suggests that higher consumption of vegetables seems to be protective for the onset of T2D in men. Thus, increasing the intake of vegetables in men should be a public health priority.

Fruits, vegetables, and health: A comprehensive narrative, umbrella review of the science and recommendations for enhanced public policy to improve intake

Fruit and vegetables (F&V) have been a cornerstone of healthy dietary recommendations; the 2015-2020 U.S. Dietary Guidelines for Americans recommend that F&V constitute one-half of the plate at each meal. F&V include a diverse collection of plant foods that vary in their energy, nutrient, and dietary bioactive contents. F&V have potential health-promoting effects beyond providing basic nutrition needs in humans, including their role in reducing inflammation and their potential preventive effects on various chronic disease states leading to decreases in years lost due to premature mortality and years lived with disability/morbidity. Current global intakes of F&V are well below recommendations. Given the importance of F&V for health, public policies that promote dietary interventions to help increase F&V intake are warranted. This externally commissioned expert comprehensive narrative, umbrella review summarizes up-to-date clinical and observational evidence on current intakes of F&V, discusses the available evidence on the potential health benefits of F&V, and offers implementation strategies to help ensure that public health messaging is reflective of current science. This review demonstrates that F&V provide benefits beyond helping to achieve basic nutrient requirements in humans. The scientific evidence for providing public health recommendations to increase F&V consumption for prevention of disease is strong. Current evidence suggests that F&V have the strongest effects in relation to prevention of CVDs, noting a nonlinear threshold effect of 800 g per day (i.e., about 5 servings a day). A growing body of clinical evidence (mostly small RCTs) demonstrates effects of specific F&V on certain chronic disease states; however, more research on the role of individual F&V for specific disease prevention strategies is still needed in many areas. Data from the systematic reviews and mostly observational studies cited in this report also support intake of certain types of F&V, particularly cruciferous vegetables, dark-green leafy vegetables, citrus fruits, and dark-colored berries, which have superior effects on biomarkers, surrogate endpoints, and outcomes of chronic disease.

Association Between Okinawan Vegetables Consumption and Risk of Type 2 Diabetes in Japanese Communities: The JPHC Study

Background

Some Okinawan vegetables have been reported to have anti-diabetic activity; however, no prospective cohort study has clarified whether consumption of Okinawan vegetables is associated with a risk of type 2 diabetes. This study aimed to determine the association between consumption of Okinawan vegetables and risk of type 2 diabetes through a large-scale, population-based, prospective study in Japan.

Methods

We examined 10,732 participants (4,714 men and 6,018 women) aged 45–74 years who resided in Okinawa. Participants were asked to answer a 147-item food frequency questionnaire. We calculated the overall amount of Okinawan vegetables consumed and the amount of seven specific kinds of Okinawan vegetables consumed. The odds ratios (ORs) for self-reported type 2 diabetes during 5 years of follow-up were estimated via multivariate logistic regression analysis.

Results

During the 5-year period, 216 new cases (123 men and 93 women) of type 2 diabetes were reported. Comparing the highest tertile to the lowest tertile of intake, the overall amount of Okinawan vegetables consumed was not associated with risk of type 2 diabetes in men (OR 1.22; 95% confidence interval [CI], 0.74–2.01, P-trend = 0.53) or in women (OR 0.96; 95% CI, 0.57–1.62, P-trend = 0.89). The consumption of seven specific kinds of Okinawan vegetables was also not associated with the risk of type 2 diabetes.

Conclusions

The consumption of total Okinawan vegetables was not associated with the risk of type 2 diabetes.

Snack selection influences glucose metabolism, antioxidant capacity and cholesterol in healthy overweight adults: A randomized parallel arm trial

Including carbohydrate/fructose-rich foods (predominantly fruit) in the diets of overweight individuals can improve chronic disease risk factors. We hypothesized dried plums (DP) would improve nutrient consumption, total antioxidant capacity (TAC), lipid and adipokine profiles, and would decrease adiposity and inflammation. To test this, we studied the effects of 8-weeks of twice-daily snacking of macronutrient-matched 100kcal servings of DP or refined carbohydrate-rich snack (low-fat muffins: LFM) on daily energy and nutrient consumption, and chronic disease risk factors in overweight adults. Body weight/composition, waist circumference, blood pressure, plasma glucose, insulin, c-peptide, lipids, TAC, adipokines and inflammation were measured at baseline and throughout the study. Postprandial glucose and insulin were assessed following assigned test foods at baseline and 8-weeks. Repeated measures ANOVAs were undertaken to examine group and time differences. Post-hoc independent and paired samples t-tests were conducted where necessary. DP increased (P<.05) overall intake of dietary fiber and potassium, and TAC, from baseline to 8-weeks. Baseline postprandial glycemia tended (P=.09) to be lower with DP versus LFM, while both groups had a decreased response after 8-weeks. Postprandial insulinemia was lower (P<.05) for DP at both time-points. No differences in body weight/composition, blood pressure, or fasting glucose, insulin, triglycerides, total cholesterol, HDL-C, inflammation or adipokines were detected. Low-density lipoprotein cholesterol (LDL-C) increased (P<.05) throughout the trial following LFM. Overall, DP lessened postprandial insulinemia, improved nutrient consumption and plasma TAC, and maintained plasma LDL-C compared to a macronutrient-matched refined carbohydrate snack, which could decrease chronic disease risk.

Biotechnological approaches in glucosinolate production

Glucosinolates (GLSs) are sulfur-rich, amino acid-derived defense compounds characteristic of the Brassicales order. In the past, GLSs were mostly known as anti-nutritional factors in fodder, biopesticides in agriculture, and flavors in condiments such as mustard. However, in recent times, GLSs have received increased attention as promoters of human health. This has spurred intensive research towards generating rich sources of health-promoting GLSs. We provide a comprehensive overview of the biotechnological approaches applied to reach this goal. This includes optimization of GLS production and composition in native, GLS-producing plants, including hairy root and cell cultures thereof, as well as synthetic biology approaches in heterologous hosts, such as tobacco and the microbial organisms Escherichia coli and Saccharomyces cerevisiae. The progress using these different approaches is discussed.

Impact of serum cholesterol esterification rates on the development of diabetes mellitus in a general population

Background

Lecithin:cholesterol acyltransferase (LCAT) plays an important role in cholesterol esterification in serum. Serum LCAT activity is elevated in patients with serum high triglyceride and low high-density lipoprotein-cholesterol (HDL-C) concentrations, both of which are related to metabolic syndrome and subsequent diabetes mellitus, referred to as lipotoxicity. We hypothesized that increased serum LCAT activity could predict future risk of diabetes mellitus in a general Japanese population.

Methods

We prospectively studied 1496 individuals aged 20–86 years without histories of diabetes mellitus at baseline. Serum lipid concentrations, glucose parameters, and LCAT activity measured as the serum cholesterol esterification rate, were evaluated.

Results

During 11 years of follow-up, 46 newly diagnosed patients with diabetes mellitus were reported. After adjustment for plasma glycosylated hemoglobin A1c (HbA1c) levels, the relative risks (RRs) for the development of diabetes mellitus were 5.45 [95% confidence interval (95% CI) 2.37–12.55; P <  0.001] for body-mass index, 0.22 (95% CI, 0.09–0.53; P = 0.001) for HDL-C, 4.81 (95% CI, 1.96–11.77; P = 0.001) for triglyceride, and 4.64 (95% CI, 1.89–11.41; P = 0.001) for LCAT activity. After adjustment for HbA1c, total cholesterol, triglyceride, HDL-C, phospholipid, and free fatty acid levels, the RR of LCAT activity for future risk of diabetes mellitus remained significant (RR, 4.93; 95% CI,1.32–18.41; P = 0.018). In this analysis, we found a significant association between LCAT activity and risk of diabetes mellitus in men but not in women.

Conclusion

Increased serum cholesterol esterification rate is a potent predictor for future diabetes mellitus.

Dietary habits associated with reduced insulin resistance: The Nagahama study

AIMS

To investigate the association between insulin resistance assessed by a homeostasis model and dietary habits.

METHODS

Cross-sectional analysis using a community-based cohort, the Nagahama Prospective Cohort for Comprehensive Human Bioscience. Multiple linear regression analysis was performed with log HOMA-IR or log HOMA-β as the dependent variable and 20 dietary habits, tobacco smoking, medical history, family medical history of diabetes, age and BMI as the simultaneous independent variables in each sex separately.

RESULTS

Females (n = 2956) eating fish dishes every day had a HOMA-IR 0.90 times that of the reference group (P = 0.043). Females eating miso-soup every day had a HOMA-IR 0.95 times that of the reference group (P = 0.038). Males (n = 1371) eating vegetable dishes every day had a HOMA-IR 0.91 times that of the reference group (P = 0.003). Males eating egg dishes 4 to 5 times per week had a HOMA-IR 1.14 times that of the reference group (P = 0.011). Males eating fruits every day had a HOMA-IR 1.13 that of the reference group (P = 0.008).

CONCLUSIONS

Dietary habits associated with lower insulin resistance were eating fish dishes, miso soup or vegetable dishes every day and eating staple foods for dinner, egg dishes or fruits less frequently.

Dietary glucosinolates and risk of type 2 diabetes in 3 prospective cohort studies

Background

Glucosinolates are a group of phytochemicals that are abundant in cruciferous vegetables and precursors of the potentially chemopreventive isothiocyanates. Isothiocyanates may reduce oxidative stress and inflammation, but little is known regarding the association between glucosinolate intake and risk of type 2 diabetes (T2D).

Objective

To evaluate the association between the intake of glucosinolates and the incidence of T2D in US men and women.

Design

This prospective cohort study investigated 200,907 women and men [71,256 women from the Nurses' Health Study (NHS; 1984-2012), 88,293 women from the NHS II (1991-2013), and 41,358 men from the Health Professionals Follow-Up Study (1986-2012)] who were free of diabetes, cardiovascular disease, and cancer at baseline. Diet was assessed using validated semiquantitative food frequency questionnaires. Self-reported T2D incidence was confirmed by a supplementary questionnaire.

Results

During follow-up in the 3 cohorts, we accumulated 4,303,750 person-years and 16,567 incident cases of T2D. After adjustment for major lifestyle and dietary risk factors for T2D, participants in the highest quintile of total glucosinolate intake had a 19% higher risk (95% CI: 13%, 25%; Ptrend < 0.001) of T2D than did those in the lowest quintile. The intake of 3 major glucosinolate subtypes was consistently and significantly associated with T2D risk, with pooled HRs ranging from 1.13 to 1.18 (all Ptrend < 0.001). A significant association was also observed between total cruciferous vegetable consumption and T2D (HR: 1.16; 95% CI :1.07, 1.25; Ptrend < 0.001). These associations persisted in subgroups defined by demographic, lifestyle, and other dietary factors.

Conclusions

Dietary glucosinolate intake was associated with a moderately higher risk of T2D in US adults. These results need to be replicated in further investigations, including biomarker-based studies. Mechanistic research is also needed to understand the relation between exposures to glucosinolates, isothiocyanates, and other metabolites with T2D risk. This trial was registered at clinicaltrials.gov as NCT03366532.

Green leafy and cruciferous vegetable consumption and risk of type 2 diabetes: results from the Singapore Chinese Health Study and meta-analysis

Several previous prospective studies suggest that consumption of green leafy and cruciferous vegetables may lower the risk of type 2 diabetes (T2D). We investigated the association between consumption of different types of vegetables in relation to T2D risk in an Asian Population. We included 45 411 participants (age range: 45-74 years) of the Singapore Chinese Health Study (SCHS) free of diabetes, cancer or CVD at baseline (1993-1998). Dietary information was collected using a validated FFQ. Physician-diagnosed incident diabetes was reported at follow-up I (1999-2004) and II (2006-2010) interviews. Cox proportional hazards regression was used to estimate hazard ratio (HR) and 95 % CI of T2D risk. An updated meta-analysis was also conducted to summarise results for green leafy and cruciferous vegetables. During 494 741 person-years of follow-up, 5207 incident T2D occurred. After adjustment for potential confounders, neither total vegetables (top v. bottom quintile HR=1·08; 95 % CI 0·98, 1·18, P trend=0·66) nor specific vegetables including dark green leafy vegetables (HR=1·05; 95 % CI 0·96, 1·15, P trend=0·21) and cruciferous vegetables (HR=0·97; 95 % CI 0·88, 1·06, P trend=0·29) were substantially associated with risk of T2D. A meta-analysis (eleven studies with 754 729 participants and 58 297 cases) including the SCHS and all previous prospective studies suggested borderline significant inverse associations between green leafy (summary relative risk (RR)=0·91; 95 % CI 0·84, 1·00) and cruciferous vegetable consumption (RR=0·87; 95 % CI 0·76, 1·00) and T2D risk, with moderate-to-high heterogeneity. In conclusion, green leafy or cruciferous vegetable consumption was not substantially associated with risk of T2D in an Asian population. Meta-analysis of available cohort data indicated that evidence for a beneficial effect of green leafy or cruciferous vegetable consumption on T2D risk is not convincing.

Different Dietary Patterns and New-Onset Diabetes Mellitus After Kidney Transplantation: A Cross-Sectional Study

OBJECTIVE

To verify the association of dietary patterns and dietary components with new-onset diabetes mellitus after transplantation (NODAT).

DESIGN

Cross-sectional study.

SUBJECTS

Adult kidney transplant recipients, without history of diabetes before transplantation, who received a kidney transplant and were followed up for at least 1 year. One hundred and sixteen subjects recruited between January 2013 and August 2014. Diagnosis of NODAT was established according to the American Diabetes Association criteria for type 2 diabetes.

METHODS

Demographic, clinical, and anthropometric data were collected. Dietary intake was assessed by food frequency questionnaire, administered by a registered dietitian. Dietary patterns were identified by cluster analysis. Chi-square test was used to verify the association between dietary patterns and NODAT. Total energy, fiber, and cholesterol intake were calculated. Consumption of macronutrients, carbohydrates, proteins, and fats (total fats and saturated, monounsaturated, polyunsaturated and trans fatty acids), were expressed in percentage of total energy intake.

RESULTS

Twenty-eight patients developed NODAT in the follow-up period. They presented higher body mass index and body fat percentage, as well as higher levels of triglycerides and urinary protein/creatinine ratio than the non-NODAT group. Two dietary patterns, I and II, were identified. Pattern II was characterized by higher intake of total, saturated, monounsaturated, and trans fats than pattern I. No association between the dietary patterns and NODAT was identified (P = .905), and there was no difference in the distribution of macronutrients, dietary fiber, and dietary cholesterol between the groups with and without NODAT.

CONCLUSION

Posttransplant dietary patterns were not different between patients with and without NODAT. Further larger and prospective studies are needed to evaluate a possible relationship between dietary components and NODAT incidence in kidney transplant recipients.

The contribution of alliaceous and cruciferous vegetables to dietary sulphur intake

Despite its importance in many areas of human metabolism, there are no recommended daily intake guide lines for sulphur. It is generally assumed that most dietary sulphur originates from intake of methionine and cysteine. We estimated sulphur intake from food diaries, and validated the results with the use of a duplicate diet analyses. Sulphur intake estimations were highly correlated with that obtain through an elemental analysis of duplicate diets, with a mean±sd daily intakes of 956±327.9mg estimated from diet diary analyses and 935±329.9mg estimated by a duplicate diet analyses. Sulphur intake from alliaceous and cruciferous vegetables contributed up to 42% of total sulphur intake. Daily intake estimation comparisons through diet diary analyses and duplicate diet for other elements showed good agreement, except for sodium and zinc, in which analyses of 24h diet dairies overestimated intake by 35% and 52%, respectively.

Health risk factors associated with meat, fruit and vegetable consumption in cohort studies: A comprehensive meta-analysis

The aim of this study was to perform a meta-analysis to test the association between red, processed, and total meat, as well as fruit and vegetable consumption, and selected health risk factors, including body weight status, smoking habit, physical activity level, level of education, and alcohol drinking in cohort studies on non-communicable disease. A systematic search of electronic databases was performed to identify relevant articles published up to March 2017. In a two-stage approach, frequency-weighted linear regression coefficients were first calculated for each variable, and then combined across studies through meta-regression. Ninety-eight studies including 20 on red meat, 6 on processed meat, 12 on total meat, 37 on fruit and vegetable combined, 21 on fruit and 24 on vegetable consumption were analyzed. Intake of red meat was positively associated with BMI, percentage of overweight and obese, low physical activity, and current and ever smoking and inversely associated with percentage of non-smokers and high physically active individuals. Similar associations were found for red meat were found, although based on fewer data. Intake of fruits and vegetables was positively associated with prevalence of non-smokers, high education and high physical activity, and similar results were found when examining fruit and vegetable consumption separately. Stratification by geographical area revealed that some associations were stronger in US rather than European or Asian cohorts. In conclusions, the distribution of health risk factors associated with high meat and fruit/vegetable consumption may differ from those of low-consumers. Some of these differences may mediate, confound, or modify the relation between diet and non-communicable disease risk.

Influence of temperate, subtropical, and tropical fruit consumption on risk of type 2 diabetes in an Asian population

Background: Findings on the relation between fruit consumption and the risk of type 2 diabetes mellitus (T2DM) have been inconsistent.Objectives: We examined whether the consumption of total, temperate, subtropical, and tropical fruit is associated with T2DM risk and whether differences in the carbohydrate quality of fruit influence T2DM risk in Asians.Design: We included 45,411 participants in the Singapore Chinese Health Study who were 45-74 y old and had no diabetes, cancer, or cardiovascular disease at recruitment (1993-1998). Fruit intake was assessed with the use of a validated food-frequency questionnaire. Physician-diagnosed incident T2DM cases were reported at follow-up 1 (1999-2004) and follow-up 2 (2006-2010) interviews. Cox proportional hazards regression was used to estimate HRs and 95% CIs of diabetes risk.Results: In 494,741 person-years of follow-up, 5207 participants developed T2DM. After adjustment for lifestyle and dietary risk factors, high total fruit consumption was not consistently associated with lower T2DM risk [men: HR of 1.33 (95% CI: 1.04, 1.71) for ≥3 servings/d compared with <1 serving/wk (P-trend = 0.17); women: HR of 0.88 (95% CI: 0.71, 1.11) (P-trend = 0.008); P-interaction = 0.003]. The direct association in men was observed for higher-glycemic index (GI) fruit [HR: 1.51 (95% CI: 1.22, 1.86) for ≥1 serving/d compared with rarely consumed; P-trend = 0.001] but not for lower or moderate GI fruit. In women, the consumption of temperate fruit, but not of subtropical or tropical fruit, was associated with lower T2DM risk [HR: 0.79 (95% CI: 0.67, 0.92) for ≥1 serving/d compared with rarely; P-trend = 0.006].Conclusions: The consumption of temperate fruit, such as apples, was associated with a lower risk of T2DM in women, whereas the consumption of higher-GI fruit, such as bananas, was associated with higher risk in men. The impact of fruit consumption on the risk of diabetes may differ by the type of fruit, which may reflect differences in the glycemic impact or phytochemical content.

High Dietary Acid Load Score Is Associated with Increased Risk of Type 2 Diabetes in Japanese Men: The Japan Public Health Center-based Prospective Study

BACKGROUND

Diet-induced metabolic acidosis has been linked to cardiometabolic abnormalities in Westerners, but the evidence on this issue is scarce in Asians.

OBJECTIVE

The present study prospectively examined the association between dietary acid load and type 2 diabetes (T2D) in Japanese adults.

METHODS

Study participants were 27,809 men and 36,851 women, aged 45-75 y, who completed a dietary questionnaire of the second survey of the Japan Public Health Center-based Prospective Study and had no previous history of T2D. Dietary intake was assessed by using a validated 147-item food-frequency questionnaire. Potential renal acid load (PRAL) and net endogenous acid production (NEAP) scores were derived from the nutrient intake. A multilevel logistic regression model was used to estimate ORs and 95% CIs of self-reported, physician-diagnosed T2D over 5 y, with adjustment for potential confounding variables.

RESULTS

A total of 1191 cases of newly diagnosed T2D were reported. PRAL score was positively associated with T2D in men; the multivariable-adjusted ORs (95% CIs) for the lowest through the highest quartiles of PRAL were 1.00, 1.09 (0.87, 1.36), 1.10 (0.88, 1.37), and 1.25 (1.01, 1.55) (P-trend = 0.047). Further adjustment for dietary intake strengthened the association. NEAP score was not associated with the risk of T2D (P-trend = 0.20). In stratified analyses, the positive association between PRAL and T2D was confined to younger men (age <50 y; P-trend = 0.046). There was no association between dietary acid load score and T2D in women.

CONCLUSION

A high dietary acid load score is associated with an increased risk of T2D in Japanese men.

Higher intake of fruits, vegetables or their fiber reduces the risk of type 2 diabetes: A meta-analysis

Aims/Introduction

Some previous studies reported no significant association of consuming fruit or vegetables, or fruit and vegetables combined, with type 2 diabetes. Others reported that only a greater intake of green leafy vegetables reduced the risk of type 2 diabetes. To further investigate the relationship between them, we carried out a meta‐analysis to estimate the independent effects of the intake of fruit, vegetables and fiber on the risk of type 2 diabetes.

Materials and Methods

Searches of MEDLINE and EMBASE for reports of prospective cohort studies published from 1 January 1966 to 21 July 2014 were carried out, checking reference lists, hand‐searching journals and contacting experts.

Results

The primary analysis included a total of 23 (11 + 12) articles. The pooled maximum‐adjusted relative risk of type 2 diabetes for the highest intake vs the lowest intake were 0.91 (95% confidence interval [CI] 0.87–0.96) for total fruits, 0.75 (95% CI 0.66–0.84) for blueberries, 0.87 (95% CI 0.81–0.93) for green leafy vegetables, 0.72 (95% CI 0.57–0.90) for yellow vegetables, 0.82 (95% CI 0.67–0.99) for cruciferous vegetables and 0.93 (95% CI 0.88–0.99) for fruit fiber in these high‐quality studies in which scores were seven or greater, and 0.87 (95% CI 0.80–0.94) for vegetable fiber in studies with a follow‐up period of 10 years or more.

Conclusions

A higher intake of fruit, especially berries, and green leafy vegetables, yellow vegetables, cruciferous vegetables or their fiber is associated with a lower risk of type 2 diabetes.

Fruit intake decreases risk of incident type 2 diabetes: an updated meta-analysis

Association between fruit intake and risk of type 2 diabetes is inconsistent. In this study, we performed a meta-analysis of all prospective cohort studies to clarify the association between fruit intake and risk of type 2 diabetes. Relevant studies were identified by searches of the PubMed and Embase databases up to November 2013. The summary relative risks of association were obtained using a fixed- or random-effects model. A total of nine prospective studies (403,259 participants, including 27,940 with incident type 2 diabetes) from seven publications were included in the meta-analysis of fruit intake and risk of type 2 diabetes. We found that individuals in the highest category of fruit intake had a reduced risk of type 2 diabetes (relative risk 0.92, 95 % confidence interval 0.86-0.97, p = 0.003) compared to those in the lowest category, with moderate evidence of between-study heterogeneity (I (2) = 37.6 %, p = 0.12). There was an evident non-linear association of fruit intake with type 2 diabetes (P for nonlinearity <0.001). A non-linear threshold of 200 g/day of fruit intake was identified and the risk of type 2 diabetes reduced by about 13 % at this cut-off. Our findings are consistent with diet recommendations to consume about 200 g/day of fruits to prevent type 2 diabetes.

Fruit and vegetable intake and risk of type 2 diabetes mellitus: meta-analysis of prospective cohort studies

OBJECTIVE

To clarify and quantify the potential dose-response association between the intake of fruit and vegetables and risk of type 2 diabetes.

DESIGN

Meta-analysis and systematic review of prospective cohort studies.

DATA SOURCE

Studies published before February 2014 identified through electronic searches using PubMed and Embase.

ELIGIBILITY CRITERIA FOR SELECTING STUDIES

Prospective cohort studies with relative risks and 95% CIs for type 2 diabetes according to the intake of fruit, vegetables, or fruit and vegetables.

RESULTS

A total of 10 articles including 13 comparisons with 24,013 cases of type 2 diabetes and 434,342 participants were included in the meta-analysis. Evidence of curve linear associations was seen between fruit and green leafy vegetables consumption and risk of type 2 diabetes (p=0.059 and p=0.036 for non-linearity, respectively). The summary relative risk of type 2 diabetes for an increase of 1 serving fruit consumed/day was 0.93 (95% CI 0.88 to 0.99) without heterogeneity among studies (p=0.477, I(2)=0%). For vegetables, the combined relative risk of type 2 diabetes for an increase of 1 serving consumed/day was 0.90 (95% CI 0.80 to 1.01) with moderate heterogeneity among studies (p=0.002, I(2)=66.5%). For green leafy vegetables, the summary relative risk of type 2 diabetes for an increase of 0.2 serving consumed/day was 0.87 (95% CI 0.81 to 0.93) without heterogeneity among studies (p=0.496, I(2)=0%). The combined estimates showed no significant benefits of increasing the consumption of fruit and vegetables combined.

CONCLUSIONS

Higher fruit or green leafy vegetables intake is associated with a significantly reduced risk of type 2 diabetes.

Incidence of type 2 diabetes in Japan: a systematic review and meta-analysis

BACKGROUND

The definition of incident type 2 diabetes varies across studies; hence, the actual incidence of type 2 diabetes in Japan is unclear. Here, we reviewed the various definitions of incident type 2 diabetes used in previous epidemiologic studies and estimated the diabetes incidence rate in Japan.

METHODS

We searched for related literature in the MEDLINE, EMBASE, and Ichushi databases through September 2012. Two reviewers selected studies that evaluated incident type 2 diabetes in the Japanese population.

RESULTS

From 1824 relevant articles, we included 33 studies with 386,803 participants. The follow-up period ranged from 2.3 to 14 years and the studies were initiated between 1980 and 2003. The random-effects model indicated that the pooled incidence rate of diabetes was 8.8 (95% confidence interval, 7.4-10.4) per 1000 person-years. We observed a high degree of heterogeneity in the results (I(2) = 99.2%; p < 0.001), with incidence rates ranging from 2.3 to 52.6 per 1000 person-years. Three studies based their definition of incident type 2 diabetes on self-reports only, 10 on laboratory data only, and 20 on self-reports and laboratory data. Compared with studies defining diabetes using laboratory data (n = 30; pooled incidence rate = 9.6; 95% confidence interval = 8.3-11.1), studies based on self-reports alone tended to show a lower incidence rate (n = 3; pooled incidence rate = 4.0; 95% confidence interval = 3.2-5.0; p for interaction < 0.001). However, stratified analyses could not entirely explain the heterogeneity in the results.

CONCLUSIONS

Our systematic review and meta-analysis indicated the presence of a high degree of heterogeneity, which suggests that there is a considerable amount of uncertainty regarding the incidence of type 2 diabetes in Japan. They also suggested that laboratory data may be important for the accurate estimation of the incidence of type 2 diabetes.

Fruit consumption and risk of type 2 diabetes: results from three prospective longitudinal cohort studies

OBJECTIVE

To determine whether individual fruits are differentially associated with risk of type 2 diabetes.

DESIGN

Prospective longitudinal cohort study.

SETTING

Health professionals in the United States.

PARTICIPANTS

66,105 women from the Nurses' Health Study (1984-2008), 85,104 women from the Nurses' Health Study II (1991-2009), and 36,173 men from the Health Professionals Follow-up Study (1986-2008) who were free of major chronic diseases at baseline in these studies.

MAIN OUTCOME MEASURE

Incident cases of type 2 diabetes, identified through self report and confirmed by supplementary questionnaires.

RESULTS

During 3,464,641 person years of follow-up, 12,198 participants developed type 2 diabetes. After adjustment for personal, lifestyle, and dietary risk factors of diabetes, the pooled hazard ratio of type 2 diabetes for every three servings/week of total whole fruit consumption was 0.98 (95% confidence interval 0.97 [corrected] to 0.99). With mutual adjustment of individual fruits, the pooled hazard ratios of type 2 diabetes for every three servings/week were 0.74 (0.66 to 0.83) for blueberries, 0.88 (0.83 to 0.93) for grapes and raisins, 0.89 (0.79 to 1.01) for prunes, 0.93 (0.90 to 0.96) for apples and pears, 0.95 (0.91 to 0.98) for bananas, 0.95 (0.91 to 0.99) for grapefruit, 0.97 (0.92 to 1.02) for peaches, plums, and apricots, 0.99 (0.95 to 1.03) for oranges, 1.03 (0.96 to 1.10) for strawberries, and 1.10 (1.02 to 1.18) for cantaloupe. The pooled hazard ratio for the same increment in fruit juice consumption was 1.08 (1.05 to 1.11). The associations with risk of type 2 diabetes differed significantly among individual fruits (P<0.001 in all cohorts).

CONCLUSION

Our findings suggest the presence of heterogeneity in the associations between individual fruit consumption and risk of type 2 diabetes. Greater consumption of specific whole fruits, particularly blueberries, grapes, and apples, is significantly associated with a lower risk of type 2 diabetes, whereas greater consumption of fruit juice is associated with a higher risk.