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1.
High consumption of vegetables and fruits is associated with reduced risk for cardiovascular disease. However, little information is available about diets based predominantly on consumption of fruits and their health consequences. We investigated the effects of an extremely high dietary intake of raw vegetables and fruits (70-100% raw food) on serum lipids and plasma vitamin B-12, folate, and total homocysteine (tHcy). In a cross-sectional study, the lipid, folate, vitamin B-12, and tHcy status of 201 adherents to a raw food diet (94 men and 107 women) were examined. The participants consumed approximately 1500-1800 g raw food of plant origin/d mainly as vegetables or fruits. Of the participants, 14% had high serum LDL cholesterol concentrations, 46% had low serum HDL cholesterol, and none had high triglycerides. Of raw food consumers, 38% were vitamin B-12 deficient, whereas 12% had an increased mean corpuscular volume (MCV). Plasma tHcy concentrations were correlated with plasma vitamin B-12 concentrations (r = -0.450, P < 0.001), but not with plasma folate. Plasma tHcy and MCV concentrations were higher in those in the lowest quintile of consumption of food of animal origin (P(trend) < 0.001). This study indicates that consumption of a strict raw food diet lowers plasma total cholesterol and triglyceride concentrations, but also lowers serum HDL cholesterol and increases tHcy concentrations due to vitamin B-12 deficiency.  相似文献   

2.
Watermelon is a rich natural source of lycopene, a carotenoid of great interest because of its antioxidant capacity and potential health benefits. Assessment of bioavailability of lycopene from foods has been limited to tomato products, in which heat processing promotes lycopene bioavailability. We examined the bioavailability of lycopene from fresh-frozen watermelon juice in a 19-wk crossover study. Healthy, nonsmoking adults (36-69 y) completed three 3-wk treatment periods, each with a controlled, weight-maintenance diet. Treatment periods were preceded by "washout" periods of 2-4 wk during which lycopene-rich foods were restricted. All 23 subjects consumed the W-20 (20.1 mg/d lycopene, 2.5 mg/d beta-carotene from watermelon juice) and C-0 treatments (controlled diet, no juice). As a third treatment, subjects consumed either the W-40 (40.2 mg/d lycopene, 5.0 mg/d beta-carotene from watermelon juice, n = 12) or T-20 treatment (18.4 mg/d lycopene, 0.6 mg/d beta-carotene from tomato juice, n = 10). After 3 wk of treatment, plasma lycopene concentrations for the W-20, W-40, T-20 and C-0 treatments were (least squares means +/- SEM) 1078 +/- 106, 1183 +/- 139, 960 +/- 117 and 272 +/- 27 nmol/L, respectively. Plasma concentrations of beta-carotene were significantly greater after W-20 (574 +/- 49 nmol/L) and W-40 (694 +/- 73 nmol/L) treatments than after the C-0 treatment (313 +/- 27 nmol/L). Plasma lycopene concentrations did not differ at wk 3 after W-20, W-40 and T-20 treatments, indicating that lycopene was bioavailable from both fresh-frozen watermelon juice and canned tomato juice, and that a dose-response effect was not apparent in plasma when the watermelon dose was doubled.  相似文献   

3.
BACKGROUND: Previous studies of associations between diet, obesity, and blood concentrations of alpha-tocopherol and beta-carotene have been equivocal. Furthermore, most studies used only body mass index (BMI) as an obesity measure. OBJECTIVES: Our objectives were to examine the associations between energy and nutrient intakes, alcohol consumption, tobacco use, and serum cholesterol and serum concentrations of alpha-tocopherol and beta-carotene, and to examine the associations between different measures of general and central adiposity and serum concentrations of alpha-tocopherol and beta-carotene. DESIGN: This was a cross-sectional, population-based study of 253 men and 276 women aged 46-67 y. Nutrient data were collected by a modified diet history method. Measures of obesity included BMI, percentage of body fat (impedance analysis), waist-to-hip ratio, and waist circumference. The associations between serum nutrient concentrations and the other factors were examined by multiple linear regression. RESULTS: Twenty-one percent of men and 34% of women used antioxidant supplements. The mean BMI was 26.1 in men and 25.4 in women. Serum beta-carotene concentration was positively associated with serum cholesterol concentration, fiber intake, and beta-carotene intake, and negatively associated with smoking and all measures of obesity. In men, serum beta-carotene concentration was not significantly associated with central adiposity after adjustment for body fat. Serum alpha-tocopherol concentration was positively correlated with serum cholesterol, obesity, and vitamin E intake. In women, serum alpha-tocopherol concentration was also positively associated with intakes of ascorbic acid and selenium. Serum alpha-tocopherol concentration was associated with central adiposity after adjustment for body fat. CONCLUSION: Serum beta-carotene and alpha-tocopherol concentrations have different associations with diet, smoking, general adiposity, and central adiposity.  相似文献   

4.
Although taurine is not dietarily essential for dogs, taurine deficiency and dilated cardiomyopathy (DCM) are sporadically reported in large-breed dogs. Taurine status and husbandry were examined in 216 privately owned Newfoundlands, a giant dog breed with high incidence of idiopathic DCM (1.3-2.5%). Plasma taurine concentration was positively correlated (P < 0.01) with plasma cyst(e)ine (r = 0.37) and methionine (r = 0.35) concentrations and was similar across age, sex, neutering status, body weight, and body-condition scores. Plasma taurine concentration was low (< or =40 micromol/L) in 8% of dogs. Dogs with low plasma taurine were older, less active, had more medical problems and treatments, and had lower plasma albumin, cyst(e)ine, tryptophan, and alpha-amino-n-butyric acid concentrations than the other dogs (P < 0.05). Of 9 taurine-deficient, clinically evaluated dogs, 3 had DCM that was reversed by taurine supplementation and 1 had retinal degeneration. When given a diet apparently adequate in sulfur amino acids (5.4 g/kg) for 3 wk, 6 Newfoundlands (52.5 +/- 2.3 kg, 3.5-7 y), compared with 6 Beagles (13.2 +/- 2.3 kg, 5.5 y), had lower (P < 0.01) concentrations of plasma taurine (49 +/- 16 vs. 97 +/- 25 micromol/L) and cyst(e)ine and blood glutathione, lower (P < 0.01) de novo taurine synthesis (59 +/- 15 vs. 124 +/- 27 mg x kg(-0.75) x d(-1)), and greater (P < 0.05) fecal bile acid excretion (1.7 +/- 0.2 vs. 1.4 +/- 0.2 micromol/g). Newfoundlands would appear to have a higher dietary sulfur amino acid requirement than Beagles, a model breed used in nutrient requirement determinations.  相似文献   

5.
The Paleolithic diet is promoted worldwide for improved gut health. However, there is little evidence available to support these claims, with existing lite  相似文献   

6.
Higher plasma lycopene concentrations have been associated with a reduced risk of several chronic diseases. Determinants of lycopene concentrations in humans have received limited attention. We had blood lycopene concentrations and lycopene consumption data available from 111 participants in a two-center cancer prevention trial involving beta-carotene and examined determinants of plasma lycopene levels cross-sectionally. The median plasma lycopene level was 0.59 micromol/L (range 0.07-1.79). Low plasma concentrations of lycopene were associated with the following variables in univariate analyses: study site (Florida lower than Connecticut, P = 0.001), being nonmarried (P = 0.02), having lower income (P = 0.003), being nonwhite race/ethnicity (P = 0.03), having lower dietary lycopene intake (r = 0.29, P = 0.002), having lower plasma cholesterol (r = 0. 43, P = 0.0001) and triglyceride levels (r = 0.26, P = 0.005), and consuming less vitamin C (r = 0.20, P = 0.03). Women had slightly higher plasma lycopene levels than men (0.65 vs. 0.58 micromol/L; P = 0.31), despite lower dietary intake of lycopene (1,040 vs. 1,320 microg/d; P = 0.50). Plasma lycopene levels did not differ in smokers and nonsmokers. In stepwise regression analyses, the determinants of plasma lycopene were plasma cholesterol, dietary lycopene, and marital status; these three variables explained 26% of the variance in plasma lycopene. Relatively few lifestyle and demographic factors were important determinants of plasma lycopene levels, with plasma cholesterol, marital status, and lycopene intake being of greatest importance.  相似文献   

7.
Low selenium levels in humans have been associated with several pathologies; however, an earlier animal investigation found a direct association between Se intake and total plasma homocysteine (tHcy) concentrations. To date, the importance of serum selenium levels in association with tHcy in humans has not been determined. We evaluated the cross-sectional association of blood selenium concentrations with plasma tHcy and other determinants of this cardiovascular disease risk factor. We estimated protein intake and measured the blood status of selenium, tHcy, and several other related factors in serum such as folate, vitamin B-12, and creatinine. Serum selenium was inversely associated with tHcy, explaining 5.8% of tHcy variance with respect to 2.2% accounted for by serum folate. Furthermore, there was a 63% decreased risk of higher tHcy concentrations (>14 micro mol/L) for subjects with serum selenium in the highest tertile (P = 0.013). We also found an inverse association of protein intake with tHcy in men (beta = -0.144; P = 0.036), which disappeared after controlling for serum Se concentrations (beta = -0.055; P = 0.003). In conclusion, selenium should be considered as a potential factor to lower tHcy. In addition, the described association between protein intake and homocysteine levels could be mediated by this trace element.  相似文献   

8.
The aim of the present study was to assess the influence of age on plasma concentration of alpha-tocopherol, retinol and carotenoids with a special attention paid to natural differences in body composition. Forty healthy subjects were recruited: twenty were less than 35 years old and twenty above 60 years old. Males and females were equally represented in each age group. Subjects were kept in energy balance and received controlled diets for 36 h. Fat mass and fat-free mass were determined with the (18)0-enriched water dilution technique. Plasma vitamins A and E, and carotenoid levels were determined after 12 h fasting and were shown to be similar in women and men. Plasma alpha-tocopherol concentration increased with age (+44 % elderly v. young), and correlated with % fat mass and plasma cholesterol. After adjustment for plasma cholesterol, the effect of age and % fat mass disappeared. In contrast, plasma lycopene level was 2-fold lower in the elderly than in the young group, and was inversely correlated with fat mass. When lycopene values were adjusted for fat mass, the effect of age disappeared. These results suggest that plasma levels of vitamin E and lycopene differed in the two age groups and that differences in plasma cholesterol and fat mass might participate in such an effect. Short-term vitamin intake did not appear to influence plasma vitamin concentrations.  相似文献   

9.
The hypocholesterolemic effects of phytosterols have not been evaluated in bakery products, and the addition of liposoluble antioxidants to the carrier has never been tested. We investigated the effects of consuming croissants and magdalenas (Spanish muffins) enriched with sterol esters, alpha-tocopherol and beta-carotene on plasma lipid and fat-soluble antioxidant concentrations in normocholesterolemic, habitual consumers of bakery products following their usual diet and lifestyle. Using a randomized, double-blind, placebo-controlled design, the control (C) group (n = 29) received two pieces daily (standard croissant and muffin) and the sterol ester (SE) group (n = 28), the same products with sterol esters added (3.2 g/d) for 8 wk. Total and LDL cholesterol (LDL-C) decreased in the SE group by 0.24 mmol/L (P < 0.01) and 0.26 mmol/L (P < 0.005), respectively, whereas these variables did not change in the control group. The total difference in total and LDL-C changes between groups was 0.38 mmol/L (8.9%) and 0.36 mmol/L (14.7%), respectively (P < 0.001). Within-group changes in HDL cholesterol, triacylglycerol or lipoprotein(a) concentrations did not differ. Similarly, within-group changes over time in plasma tocopherol and carotenoid concentrations did not differ between groups. Our findings suggest that bakery products are excellent carriers for phytosterols, and their consumption is associated with a decrease in total and LDL-C concentrations, with no changes in alpha-tocopherol and beta-carotene. The ability of bakery products to include sufficient quantities of beta-carotene to compensate for a potential deficiency, and the fact that their efficacy was not associated with the time of day at which they were consumed, are interesting findings.  相似文献   

10.
Lycopene is a major carotenoid with potent antioxidant properties that may provide protection against the development of type 2 diabetes mellitus (DM). In this study we examined the association between baseline dietary intakes of lycopene, lycopene-containing foods, and the subsequent development of type 2 DM in a large prospective cohort study. We analyzed a total of 35,783 women from the United States, aged > or =45 y and free from self-reported cardiovascular disease, cancer, and DM at baseline. Intakes of lycopene and total and individual tomato-based food products were assessed by a 131-item-validated semiquantitative food-frequency questionnaire. During a median follow-up of 10.2 y, 1544 cases of incident type 2 DM were documented. After adjusting for age, total energy intake, randomized treatment assignment, body mass index, and other known DM risk factors, the multivariate-adjusted relative risks and 95% CI of type 2 DM across increasing quintiles of dietary lycopene, were 1.00 (baseline), 1.10 (0.94-1.29), 1.10 (0.94-1.29), and 1.07 (0.91-1.26) (P linear trend = 0.56). Compared with women who consumed <1.5 servings/wk total tomato-based food products, women who consumed 1.5 to <4, 4 to <7, 7 to <10, and > or =10 servings/wk had multivariate relative risks (95% CI) of 1.03 (0.88-1.20), 1.02 (0.87-1.20), 1.09 (0.89-1.33), and 1.04 (0.80-1.36), respectively (P linear trend = 0.54). The associations for individual tomato-based food products were similar to the results for the combination of all tomato products. Our study found little evidence for an association between dietary intake of lycopene or lycopene-containing foods and the risk of type 2 DM.  相似文献   

11.
12.
OBJECTIVE: This study investigated the effects of soymilk on lipid metabolism in Sprague-Dawley rats fed a cholesterol-enriched (0.3%) diet. METHODS: Thirty male Sprague-Dawley rats weighing 230.0 +/- 9.8 g were randomly assigned to one of three groups: control, S1 (containing 15% soymilk powder in the diet), and S2 (22.5%). After 8 wk, lipid profiles of the plasma, liver, and feces were determined. RESULTS: Body weight gain, daily food intake, and feeding efficiency showed no differences across groups (P > 0.05). The experimental groups had significantly lower plasma levels of cholesterol, triacylglycerol, and low-density lipoprotein cholesterol than the control group (P < 0.05) at weeks 4 and 8. However, total fecal excretion of neutral steroid did not significantly differ across groups (P > 0.05). CONCLUSION: Soymilk affects the metabolism of plasma cholesterol in Sprague-Dawley rats.  相似文献   

13.
We previously demonstrated that the castration of male rats profoundly increases hepatic lycopene compared with intact controls. Here we further characterized the role of testosterone in modulating hepatic lycopene accumulation and isomer patterns in male rats. Furthermore, because castration significantly decreases ad libitum food consumption, we investigated the influence of food restriction on lycopene metabolism. Forty male F344 rats 8 wk of age were randomly assigned to one of four treatments (n = 10/group): 1) intact, free access to food, 2) castration, free access to food, 3) castration plus testosterone implants, free access to food and 4) intact, 20% food restricted. All rats were fed an AIN-based diet with 0.25 g lycopene (as 10% water-soluble beadlets)/kg diet for 3 wk. Serum testosterone was 5.31 +/- 1.46 nmol/L in intact controls allowed free access to food, reduced in castrated animals (0.52 +/- 0.10, P < 0.0001 versus controls) and intact, food-restricted rats (1.53 +/- 0.49 nmol/L, P < 0.0001 versus controls) and greater (17.23 +/- 3.09 nmol/L) in castrated rats administered testosterone (P < 0.0001 versus controls). Castrated rats accumulated approximately twice as much liver lycopene (74.5 +/- 8.5 nmol/g; P < 0.01 versus controls) as intact rats allowed free access to food (39.5 +/- 5.0) despite 13% lower dietary lycopene intake (P < 0.001; 3.38 +/- 0.07 versus 3.95 +/- 0.06 mg lycopene/d). Testosterone replacement in castrated rats returned liver lycopene concentrations (32.5 +/- 5.5 nmol lycopene/g with 3.76 +/- 0.05 mg dietary lycopene/d) to those observed in intact rats. Food restriction resulted in a 20% decrease in lycopene intake but significantly increased liver lycopene by 68% (66.3 +/- 7.9 nmol lycopene/g with 3.38 +/- 0.00 mg lycopene/d) compared with controls and castrated rats administered testosterone. These results suggest that androgen depletion and 20% food restriction increase hepatic lycopene accumulation. We hypothesize an endocrine and dietary interaction, where higher androgen concentrations and greater energy intake may stimulate lycopene metabolism and degradation.  相似文献   

14.
It has recently been suggested that fiber exerts a considerable effect on microbiota composition and on fecal short-chain fatty acid (SCFA) production, the concentration of which in the colon is important for immune regulation and for maintaining gut and overall health. To test the hypothesis that the fiber consumed in a regular diet affects fecal SCFA concentrations in the elderly, the authors investigated the association between different types of fiber intake and fecal SCFA concentrations in 32 institutionalized elderly subjects aged between 76 and 95 years. Food intake was recorded by means of a validated food frequency questionnaire. Total, soluble (pectin and hemicellulose) and insoluble (pectin, hemicellulose, Klason lignin, and cellulose) fiber was determined using Marlett Food Composition Tables. Analysis of acetic, propionic, and butyric acid concentrations was performed using gas chromatography–mass spectrometry. Potato intake was directly associated with SCFA concentrations and apple intake with propionate concentration. Of the fibers, cellulose showed an independent association with acetate and butyrate concentrations, and insoluble pectin explained a part of the variation in propionate. In conclusion, our results provide further evidence regarding the relation between diet and SCFA concentration in the elderly. The identification of an association between the regular intake of foods such as potatoes and the production of SCFAs provides an opportunity to improve public health.  相似文献   

15.
Abstract

The Inuit population is undergoing a rapid nutrition transition as a result of reduced consumption of traditional foods. This study aims to describe the differences in dietary adequacy between non-traditional and traditional eaters among Inuit populations in Nunavut, Canada. A cross-sectional survey was conducted using a culturally appropriate quantitative food frequency questionnaire. Participants included 208 Inuit adults from three isolated communities in Nunavut. Traditional eaters consumed a more nutrient-dense diet and achieved better dietary adequacy than non-traditional eaters. Traditional foods accounted for 7 and 27% of energy intake among non-traditional and traditional eaters, respectively. Non-nutrient-dense foods accounted for a greater proportion of energy intake in non-traditional eaters; however, these were consumed in significant amounts by both the groups (36 and 27% of total energy). Consumption of traditional foods is associated with greater diet quality and dietary adequacy. Efforts should be made to promote traditional and non-traditional foods of high-nutritional quality.  相似文献   

16.
17.
The objective of this study was to assess the dose-response effect of almond intake on plasma and red blood cell tocopherol concentrations in healthy adults enrolled in a randomized, crossover feeding trial. Participants were 16 healthy men and women, aged 41+/-13 years. After a 2-week run-in period, participants were fed three diets for 4 weeks each: a control diet, a low-almond diet, and a high-almond diet, in which almonds contributed 0%, 10%, and 20% of total energy, respectively. Changes in blood tocopherol levels were assayed by high pressure liquid chromatography. Incorporating almonds into the diet helped meet the revised Recommended Dietary Allowance of 15 mg/day alpha-tocopherol and increased lipid-adjusted plasma and red blood cell alpha-tocopherol concentrations. A significant dose-response effect was observed between percent energy in the diet from almonds and plasma ratio of alpha-tocopherol to total cholesterol.  相似文献   

18.
OBJECTIVE: This analysis was conducted to evaluate the association between plasma beta-carotene, alpha-carotene, lycopene, lutein/zeaxanthin, total carotenoids, retinol, alpha-tocopherol and subsequent mortality. METHODS: Blood samples collected longitudinally from 259 participants in a chemoprevention trial aimed at the prevention of second cancers of the oral cavity, pharynx, or larynx were analyzed by high performance liquid chromatography for selected micronutrients. All-cause mortality (primary outcome) and cause-specific mortality (secondary outcomes) were evaluated in relation to plasma micronutrient concentrations at baseline and longitudinally. RESULTS: A total of 61 deaths occurred over a follow-up time of up to 90 months. Cox proportional hazards models with time-dependent covariates were used for data analyses. In models adjusted for age, plasma cholesterol, time-dependent smoking, treatment arm, study site and gender, only plasma lycopene was significantly inversely associated with total mortality [hazard ratio (HR) above versus below median = 0.53, 95% confidence interval (CI) 0.30-0.93]. Plasma alpha-carotene was inversely associated (HR 0.24, 95% CI 0.08-0.75) while plasma retinol was positively associated (HR 5.12, 95% CI 1.54-17.05) with cardiovascular death. Smoking status modified plasma nutrient associations with total mortality. Lycopene (HR 0.08, 95% CI 0.02-0.36), alpha-carotene (HR 0.25, 95% CI 0.09-0.73) and total carotenoids (HR 0.22, 95% CI 0.07-0.70) were inversely associated with mortality in non-smokers, while plasma retinol (HR = 3.56, 95% CI 1.40-9.09) and alpha-tocopherol (HR = 2.47, 95% CI 1.02-5.98) were positively associated with mortality in smokers. CONCLUSIONS: Only plasma lycopene was significantly associated (inversely) with total mortality in the full study population. Smoking modifies associations between nutrients and mortality.  相似文献   

19.
beta-Carotene uptake by blood plasma and leukocytes was studied in mature beagle dogs. In expt. 1, dogs were fed once orally with 0, 50, 100 or 200 mg of beta-carotene and their blood was sampled at 0, 1. 5, 3, 6, 10, 18 and 24 h. Plasma beta-carotene concentrations increased dose-dependently to peak at 6 h postfeeding. Concentrations decreased rapidly thereafter, showing a half-life of 3 to 4 h. In expt. 2, dogs were given daily doses for seven consecutive days with 0, 12.5, 25, 50 or 100 mg beta-carotene. Plasma beta-carotene concentrations increased dose-dependently; concentrations after the last dose were two- to fourfold higher than after the first dose. In expt. 3, dogs were fed 0, 50 or 100 mg beta-carotene daily for 30 d. beta-Carotene was elevated in lymphocytes and neutrophils in supplemented dogs. Furthermore, beta-carotene was taken up by the cytosol, mitochondria, microsomes (lymphocytes and neutrophils) and nuclei (lymphocytes only), proving that dogs can absorb beta-carotene. beta-Carotene is taken up by subcellular organelles of blood lymphocytes and neutrophils and in the plasma and leukocytes beta-carotene may have physiological importance as it relates to immunity in dogs. Uptake kinetics indicated that dogs are not an appropriate animal model for studying beta-carotene absorption and metabolism in humans.  相似文献   

20.
BACKGROUND: Although the typical diet of the Mediterranean region has received much recognition over the past several years for its association with substantial health benefits, it remains unknown whether its favorable effects are mediated through changes in adiponectin concentrations. OBJECTIVE: The objective was to determine whether adherence to a Mediterranean-type diet is associated with higher plasma adiponectin concentrations. DESIGN: This study was a prospective and cross-sectional evaluation of plasma adiponectin concentrations and dietary data from 987 diabetic women from the Nurses' Health Study who had no history of cardiovascular disease at the time blood was drawn in 1990. RESULTS: Women who scored highest on a 9-point scale that measures adherence to a Mediterranean-type dietary pattern tended to be older, were less likely to be current smokers, had lower body mass indexes and waist circumferences, and had higher total energy intakes, physical activities, and plasma adiponectin concentrations than did women with the lowest scores. Median plasma adiponectin concentrations were 23% higher in women who most closely followed a Mediterranean-type diet than in low adherers after adjustment for age and energy intake (P < 0.01). Body composition, lifestyle, and medical history explained some, but not all, of the observed association between diet and adiponectin concentrations because high adherers tended to have greater adiponectin concentrations than did moderate or low adherers, even after adjustment for these variables. CONCLUSIONS: Our data suggest that, of the several components of the Mediterranean dietary pattern score, alcohol, nuts, and whole grains show the strongest association with adiponectin concentrations. Close adherence to a Mediterranean-type diet is associated with higher adiponectin concentrations.  相似文献   

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