Dietary lycopene,tomato-based food products and cardiovascular disease in women

In addition to the inverse association of dietary lycopene with various cancers, studies suggest a role for lycopene in cardiovascular disease (CVD) prevention. We determined whether the intake of lycopene or tomato-based foods is associated with the risk of CVD in a prospective cohort of 39,876 middle-aged and older women initially free of CVD and cancer. Participants completed a food-frequency questionnaire and provided self-reports of coronary risk factors. Dietary lycopene levels were divided into quintiles, and primary lycopene food sources (total tomato-based products, including tomatoes, tomato juice, tomato sauce and pizza) were categorized. During 7.2 y of follow-up, 719 CVD cases (including myocardial infarction, stroke, revascularization and CVD death) occurred. Compared with women in the 1st quintile of lycopene, those in increasing quintiles had multivariate relative risks (RR) of CVD of 1.11, 1.14, 1.15 and 0.90 (P for trend = 0.34). For the consumption of tomato-based products, women consuming 1.5 to <4, 4 to <7, 7 to <10 and >or=10 servings/wk had RR (95% CI) of CVD of 1.02 (0.82-1.26), 1.04 (0.82-1.31), 0.68 (0.49-0.96) and 0.71 (0.42-1.17) (P for trend = 0.029) compared with women consuming <1.5 servings/wk. Among lycopene food sources, those in the highest levels of tomato sauce (>or=2 servings/wk) and pizza intake (>or=2 servings/wk), with multivariate RR of 0.76 (0.55-1.05) and 0.66 (0.37-1.18), respectively, had potential reductions in CVD risk. Dietary lycopene was not strongly associated with the risk of CVD. However, the possible inverse associations noted for higher levels of tomato-based products, particularly tomato sauce and pizza, with CVD suggest that dietary lycopene or other phytochemicals consumed as oil-based tomato products confer cardiovascular benefits.     

Vegetable but not fruit consumption reduces the risk of type 2 diabetes in Chinese women

We examined associations between fruit and vegetable intake and the incidence of type 2 diabetes (T2D) in a population-based prospective study of 64,191 women with no history of T2D or other chronic diseases at study recruitment and with valid dietary information. Dietary intake was assessed by in-person interviews using a validated FFQ. During 297,755 person-years of follow-up, 1608 new cases of T2D were documented. We used a Cox regression model to evaluate the association of fruit and vegetable intake (g/d) with the risk of T2D. Quintiles of vegetable intake and T2D were inversely associated. The relative risk for T2D for the upper quintile relative to the lower quintile of vegetable intake was 0.72 (95%CI: 0.61-0.85; P < 0.01) in multivariate analysis. Individual vegetable groups were all inversely and significantly associated with the risk of T2D. Fruit intake was not associated with the incidence of diabetes in this population. Our data suggest that vegetable consumption may protect against the development of T2D.     

Plasma lycopene, other carotenoids, and the risk of type 2 diabetes in women

The authors conducted a nested case-control study from 1992 to 2003 among US women aged 45 years or older and free from cardiovascular disease and cancer to examine the prospective association among plasma lycopene, other carotenoids, and the risk of developing type 2 diabetes. During 10 years of follow-up, 470 cases of incident type 2 diabetes were selected and individually matched on age (+/- 1 year) and follow-up time to 470 nondiabetic controls. Baseline plasma levels of lycopene, alpha-carotene, beta-carotene, beta-cryptoxanthin, and lutein/zeaxanthin were similar in cases and controls (all p > 0.05). A possible crude inverse association between plasma lycopene and risk of type 2 diabetes was attenuated upon multivariate adjustment. After control for plasma total cholesterol and known diabetes risk factors, the multivariate odds ratios of type 2 diabetes in the highest versus the lowest quartile of plasma carotenoids were 1.13 (95% confidence interval (CI): 0.60, 2.13) for lycopene, 1.27 (95% CI: 0.63, 2.57) for alpha-carotene, 1.10 (95% CI: 0.57, 2.13) for beta-carotene, 0.91 (95% CI: 0.46, 1.81) for beta-cryptoxanthin, and 1.35 (95% CI: 0.68, 2.69) for lutein/zeaxanthin. There was no prospective association between baseline plasma carotenoids and the risk of type 2 diabetes in middle-aged and older women.     

Dietary flavonoids and flavonoid-rich foods are not associated with risk of type 2 diabetes in postmenopausal women

Flavonoids have anti-inflammatory and antioxidative effects and thus may protect against diabetes. Therefore, we hypothesized that consumption of flavonoids and specific food and beverage sources of flavonoids would be associated with reduced risk of incident diabetes. At baseline (1986), diet (by food frequency questionnaire) and health information were collected from 35,816 postmenopausal women free of diabetes. Self-reported incident diabetes was ascertained 5 times during the study (1987, 1989, 1992, 1997, and 2004). Cox proportional hazards regression was used to calculate hazard ratios for incident diabetes according to categories of total flavonoids and anthocyanidins, flavones, flavanones, flavonols, flavan-3-ol monomers, isoflavones, and proanthocyanidins. Hazard ratios according to intake categories of flavonoid-rich foods and beverages were also calculated (apples, pears, berries, broccoli, bran, citrus, tea, and red wine). Flavonoid consumption was not associated with diabetes risk after multivariable adjustment. Although other flavonoid-rich foods and beverages were not associated, red wine was inversely associated with diabetes. Women who reported drinking red wine >or=1 time/wk had a 16% reduced risk of diabetes than those drinking wine <1 time/wk [HR (95% CI): 0.84 (0.71, 0.99)], with parallel findings for white wine, beer, and liquor. In conclusion, these data do not support a diabetes-protective effect of flavonoids. The suggestive evidence of a protective effect of regular red wine consumption is shared with an inverse association between alcohol drinks in general and diabetes risk and may reflect the effects of nonflavonoid constituents that are common to all alcohol drinks.     

Soy food consumption is associated with lower risk of coronary heart disease in Chinese women

Soy food intake has been shown to have beneficial effects on cardiovascular disease risk factors. Data directly linking soy food intake to clinical outcomes of cardiovascular disease, however, are sparse. We examined the relationship between soy food intake and incidence of coronary heart disease (CHD) among participants in the Shanghai Women's Health Study, a population-based prospective cohort study of approximately 75000 Chinese women aged 40-70 y at the baseline survey that was conducted from 1997 to 2000. Included in this study were 64915 women without previously diagnosed CHD, stroke, cancer and diabetes at baseline. Information on usual intake of soy foods was obtained at baseline through an in-person interview using a validated food-frequency questionnaire. Cohort members were followed biennially through in-person interviews. After a mean of 2.5 y (162277 person-years) of follow-up, 62 incident cases of CHD (43 nonfatal myocardial infarctions and 19 CHD deaths) were documented. There was a clear monotonic dose-response relationship between soy food intake and risk of total CHD (P for trend = 0.003) with an adjusted relative risk (RR) of 0.25 (95% CI, 0.10-0.63) observed for women in the highest vs. the lowest quartile of total soy protein intake. The inverse association was more pronounced for nonfatal myocardial infarction (RR = 0.14; 95% CI, 0.04-0.48 for the highest vs. the lowest quartile of intake; P for trend = 0.001). This study provides, for the first time, direct evidence that soy food consumption may reduce the risk of CHD in women.     

Potato and french fry consumption and risk of type 2 diabetes in women

BACKGROUND: Potatoes, a high glycemic form of carbohydrate, are hypothesized to increase insulin resistance and risk of type 2 diabetes. OBJECTIVE: The objective was to examine prospectively the relation between potato consumption and the risk of type 2 diabetes. DESIGN: We conducted a prospective study of 84,555 women in the Nurses' Health Study. At baseline, the women were aged 34-59 y, had no history of chronic disease, and completed a validated food-frequency questionnaire. The participants were followed for 20 y with repeated assessment of diet. RESULTS: We documented 4496 new cases of type 2 diabetes. Potato and french fry consumption were both positively associated with risk of type 2 diabetes after adjustment for age and dietary and nondietary factors. The multivariate relative risk (RR) in a comparison between the highest and the lowest quintile of potato intake was 1.14 (95% CI: 1.02, 1.26; P for trend = 0.009). The multivariate RR in a comparison between the highest and the lowest quintile of french fry intake was 1.21 (95% CI: 1.09, 1.33; P for trend < 0.0001). The RR of type 2 diabetes was 1.18 (95% CI: 1.03, 1.35) for 1 daily serving of potatoes and 1.16 (95% CI: 1.05, 1.29) for 2 weekly servings of french fries. The RR of type 2 diabetes for substituting 1 serving potatoes/d for 1 serving whole grains/d was 1.30 (95% CI: 1.08, 1.57). The association between potato consumption and risk of type 2 diabetes was more pronounced in obese women. CONCLUSIONS: Our findings suggest a modest positive association between the consumption of potatoes and the risk of type 2 diabetes in women. This association was more pronounced when potatoes were substituted for whole grains.     

Urinary F2-isoprostanes are not associated with increased risk of type 2 diabetes

OBJECTIVE: Free radicals have been implicated in the etiology of type 2 diabetes. Cross-sectional studies have demonstrated associations between oxidative damage and type 2 diabetes. However, no prospective data on this association are available. RESEARCH METHODS AND PROCEDURES: A case control study was conducted within the prospective cohort of the Insulin Resistance Atherosclerosis Study: 26 cases who developed type 2 diabetes in the follow-up period and 26 controls who remained free of type 2 diabetes were randomly selected. Oxidative status was assessed by measuring 2,3-dinor-5,6-dihydro-15-F2t-isoprostane (F2-IsoPM) in baseline urine samples using gas chromatography/mass spectroscopy. Type 2 diabetes was defined by serial oral glucose tolerance tests and World Health Organization criteria. RESULTS: Urinary F2-IsoPM varied between 0.18 and 2.60 ng/mg creatinine; 25th/50th/75th percentiles were 0.42, 0.60, and 0.89, respectively. A trend toward higher levels were observed in women and in persons with impaired glucose tolerance at baseline (p = 0.1). F2-IsoPM increased with BMI (r = 0.36, p = 0.01). After adjustment for age, gender, baseline impaired glucose tolerance status, and BMI, F2-IsoPM levels were inversely associated with development of type 2 diabetes: odds ratio = 0.32 (95% confidence interval, 0.12 to 0.81) for the difference between the 75th and 25th percentiles. DISCUSSION: These results suggest that oxidative damage is not a cause of type 2 diabetes. Positive cross-sectional associations of F2-IsoPM with the risk factors for diabetes, BMI, and impaired glucose tolerance and inverse associations with development of type 2 diabetes indicate that F2-IsoPM might reflect a compensatory mechanism.     

Coffee consumption and the decreased risk of diabetes mellitus type 2

Coffee is among the most commonly consumed beverages in The Netherlands. Caffeine can acutely lower insulin sensitivity, but it is not clear whether tolerance for this effect develops after long-term regular intake. Furthermore, it is plausible that the effects of coffee are different from those of caffeine. Coffee contains hundreds of substances and there are indications that certain components may partly counter-act the effect of caffeine or may have independent beneficial effects. Intake of the coffee components chlorogenic acid, quinides, lignans, and trigonelline improved glucose metabolism in animal studies. Habitual coffee consumption has been studied in relation to the risk of diabetes mellitus type 2 in 12 cohort studies in Europe, the USA, and Japan. Generally, high coffee consumption was associated with a substantially lower risk of type-2 diabetes. The findings were similar for caffeinated and decaffeinated coffee, suggesting that the non-caffeine components of coffee may be responsible. Identification of these coffee components may lead to the development or selection of coffee types with improved effects on health.     

Frequent salad vegetable consumption is associated with a reduction in the risk of diabetes mellitus

This cross-sectional study was undertaken to investigate the association between the reported frequency of consumption of vegetables and fruits, the choice of staple carbohydrate, and glucose intolerance. One thousand one hundred twenty-two subjects aged 40-64 years in a population-based study underwent an oral glucose tolerance test, and their food consumption was assessed using a food-frequency questionnaire. The crude prevalence of undiagnosed non-insulin-dependent diabetes mellitus (NIDDM) was 4.5%, and that of impaired glucose tolerance (IGT) 16.8%. The age-standardized prevalence rates were 2.3 and 11.2%, respectively. Frequent consumption of vegetables throughout the year was inversely associated with the risk of having NIDDM (odds ratio [OR] = 0.16; 95% confidence interval [CI] = 0.04-0.69). This association was maintained after adjustment for age, gender, and family history. Vegetable consumption during the summer months had a much weaker inverse association with the risk of having NIDDM that failed to reach statistical significance. A nonsignificant inverse association between frequent consumption of fruits and NIDDM was observed. Frequent self-reported pasta and rice consumption was associated with a reduction in the risk of having IGT and NIDDM. (OR = 0.62, 95% CI = 0.44-0.87, and OR = 0.51, 95% CI = 0.27-0.99, respectively) but this relationship was not independent of age. Whether these associations reflect specific effects of particular nutrients or are a reflection of the patterning of lifestyle factors remains to be determined.     

Low-carbohydrate-diet score and risk of type 2 diabetes in women

BACKGROUND: Low-carbohydrate weight-loss diets remain popular; however, the long-term effects of these diets are not known. OBJECTIVE: The objective was to examine the association between low-carbohydrate-diet score and risk of type 2 diabetes DESIGN: We prospectively examined the association between low-carbohydrate-diet score (based on percentage of energy as carbohydrate, fat, and protein) and risk of diabetes among 85 059 women in the Nurses' Health Study. RESULTS: During 20 y of follow-up, we documented 4670 cases of type 2 diabetes. The multivariate relative risk (RR) of diabetes, after adjustment for body mass index and other covariates, in a comparison of the highest decile of low-carbohydrate-diet score with the lowest was 0.90 (95% CI: 0.78, 1.04; P for trend = 0.26). The multivariate RR for the comparison of extreme deciles of low-carbohydrate-diet score based on total carbohydrate, animal protein, and animal fat was 0.99 (95% CI: 0.85, 1.16; P for trend = 1.0), whereas the RR for a low-carbohydrate-diet score based on total carbohydrate, vegetable protein, and vegetable fat was 0.82 (95% CI: 0.71, 0.94; P for trend = 0.001). A higher dietary glycemic load was strongly associated with an increased risk of diabetes in a comparison of extreme deciles (RR: 2.47; 95% CI: 1.75, 3.47; P for trend < 0.0001)). A higher carbohydrate consumption was also associated with an increased risk of diabetes in a comparison of extreme deciles (RR: 1.26; 95% CI: 1.07, 1.49; P for trend = 0.003). CONCLUSION: These data suggest that diets lower in carbohydrate and higher in fat and protein do not increase the risk of type 2 diabetes in women. In fact, diets rich in vegetable sources of fat and protein may modestly reduce the risk of diabetes.     

E-selectin genotypes and risk of type 2 diabetes in women

Endothelial dysfunction increases risk for type 2 diabetes. We examined whether variation in the gene for E-selectin (SELE), a biomarker of endothelial dysfunction, was associated with levels of E-selectin or diabetes quantitative traits (including fasting levels of insulin and hemoglobin A(1c)) in 719 nondiabetic participants of the Nurses' Health Study or with risk of diabetes in 602 incident (over 10 years of follow-up) cases and 655 control women matched for age, race, and fasting status. Variation in three single nucleotide polymorphisms previously associated with cardiovascular disease risk and having effects on E-selectin function, S128R, G98T, and L554F, was not significantly (p > 0.05) associated with levels of E-selectin or diabetes quantitative traits, or with risk of incident diabetes in the primary analysis. Among women with low levels of subclinical inflammation (C-reactive protein levels below the population median), S128R R allele carriers had a diabetes risk factor-adjusted relative risk of incident diabetes of 1.71 (95% confidence interval, 1.04 to 2.81) relative to those with the SS genotype. Apart from an association in this subgroup, we conclude that the E-selectin variants we examined are not important genetic risk factors for type 2 diabetes in women.     

Associations between dairy products consumption and risk of type 2 diabetes: Tehran lipid and glucose study

Abstract

We aimed to examine the relationship between total dairy and dairy subtypes with the risk of type 2 diabetes (T2DM) in an Asian population. A nested case–control study of 178 cases of incident T2DM and 520 matched controls was conducted within the Tehran lipid and glucose study (TLGS). A 27% lower risk of T2DM was found per 100?g/d total dairy consumption that tend to be significant (95% CI: 0.52–1.02). Milk intake was inversely associated with diabetes after adjustment for confounders (p-trend: 0.042). Milk intake was associated with decreased T2DM risk in men (p-trend: 0.025), but not in women (p-trend: 0.527). Each 100?g/d increase in milk intake corresponded to 41% lower T2DM risk in fully adjusted model (95% CI: 0.39–0.89) in men. In conclusion, there is no significant association between diabetes and total dairy intake in the present study, but high intake of milk may reduce T2DM risk among men.     

绝经后女性2型糖尿病患者发生骨质疏松性骨折的危险因素分析

目的 探讨绝经后女性2型糖尿病(T2DM)患者发生骨质疏松性骨折的危险因素.方法 采用回顾性研究方法,选取绝经后女性T2DM骨质疏松患者220例,根据有无骨折分为骨折组(n = 100)和无骨折组(n = 120),记录患者的一般资料,收集其空腹血样本用于血糖、血脂、尿酸、HbA1c等检测.结果 骨折组BMI、TG、F...     

Metabolic inflexibility in women with PCOS is similar to women with type 2 diabetes

Background

An ability to switch between primarily oxidizing fat in the fasted state to carbohydrate in the fed state, termed metabolic flexibility, is associated with insulin sensitivity. Metabolic flexibility has been explored previously in women with polycystic ovary syndrome (PCOS), yet the independent or synergistic contributions of androgen excess and/or insulin resistance is not yet known. Therefore, the purpose of this article was to characterize metabolic flexibility in women with PCOS compared to women of normal BMI, obesity, or type 2 diabetes (T2DM).

Methods

Eighty-six weight-stable women; thirty with either PCOS (n?=?30), or fifty-six with obesity (n?=?12), T2DM (n?=?27), or normal BMI (n?=?17) underwent a hyperinsulinemic euglycemic clamp and indirect calorimetry to measure insulin sensitivity and substrate oxidation via indirect calorimetry, respectively.

Results

All analyses were adjusted for differences in age, ethnicity, and BMI between groups. Women with PCOS were less metabolically flexible compared to healthy women with obesity (p?<?0.0001), normal BMI (p?<?0.0001), but after controlling for glucose disposal rate, were similar to women with T2DM (p?=?0.99). When dividing women with PCOS above and below the mean cutoff for insulin resistance, the insulin resistant women with PCOS had lower rates of non-oxidative glucose metabolism (p?=?0.0001), higher levels of percent free testosterone (p?=?0.04), a higher free androgen index (p?=?0.006), more visceral adipose tissue (p?=?0.02), and were less metabolically flexible (p?=?0.007).

Conclusions

Women with T2DM were as metabolically inflexible as women with PCOS. When stratifying women with PCOS into those who are metabolically flexible and inflexible, the women who are inflexible display greater amounts of visceral fat and androgen excess. The inability to alter substrate use given the physiological stimulus may lead to subsequent increases in adiposity in women with PCOS thereby further worsening the insulin resistance.

Trial registration number

Clinical Trials.gov, NCT01482286. Registered 30 November 2011.

     

Systematic review and meta-analysis of soy products consumption in patients with type 2 diabetes mellitus

Clinical trials have reported the lipid-lowering effect of consuming soy products, and epidemiological studies have shown that soy intake is associated with decreased risk of type 2 diabetes mellitus (T2DM). The aim of this meta-analysis was to systematically review the effects of soy products consumption on serum lipid profiles and glycaemic control in T2DM patients. Potential papers were initially searched from PubMed (1966 to 2010) and Cochrane Library (1984 to 2010) without language limitations. All randomized controlled trials were included in which soy products supplementation was the only intervention in subjects with type 2 diabetes. Weighted mean effect size was calculated for net changes in serum lipids and fasting glucose concentrations using fixed-effect or random-effect models. Previously defined subgroup analyses were performed to identify the source of heterogeneity. Eight studies were included according to the criteria. The intake of soy products was associated with a significant reduction in serum total cholesterol (by 0.42 mmol/L; 95% confidence interval (CI): -0.70, -0.14; p<0.001), triacylglycerol (by 0.22 mmol/L; 95% CI: -0.38, -0.07; p<0.001) and low-density lipoprotein-cholesterol (by 0.30 mmol/L; 95% CI: -0.60, -0.00; p<0.001), and a significant increase in high-density lipoprotein-cholesterol (0.05 mmol/L; 95% CI: 0.04, 0.06; p=0.89). There were no significant effects on fasting glucose, insulin and glycated hemoglobin. It can be concluded that intake of soy and soy products has beneficial effects in T2DM patients in relation to serum lipids.