Instruct: Given a question, retrieve relevant documents that answer the question.
Query: Are the nutrients from blended vegetables absorbed better than raw vegetables?
Epidemiological studies indicate that diets rich in fruits and vegetables (F&V) are protective against CVD. Puréed F&V products retain many beneficial components, including flavonoids, carotenoids, vitamin C and dietary fibres. The present study aimed to establish the physiological effects of acute ingestion of a F&V purée-based drink (FVPD) on vasodilation, antioxidant status, phytochemical bioavailability and other CVD risk factors. A total of twenty-four subjects, aged 30-70 years, completed the randomised, single-blind, controlled, crossover test meal study. Subjects consumed 400 ml of the FVPD, or a fruit-flavoured sugar-matched control, after following a low-flavonoid diet for 5 d. Blood and urine samples were collected throughout the study day, and vascular reactivity was assessed at 90 min intervals using laser Doppler iontophoresis. The FVPD significantly increased plasma vitamin C (P= 0·002) and total nitrate/nitrite (P= 0·001) concentrations. There was a near significant time by treatment effect on ex vivo LDL oxidation (P= 0·068), with a longer lag phase after consuming the FVPD. During the 6 h after juice consumption, the antioxidant capacity of plasma increased significantly (P= 0·003) and there was a simultaneous increase in plasma and urinary phenolic metabolites (P< 0·05). There were significantly lower glucose and insulin peaks after ingestion of the FVPD compared with control (P= 0·019 and 0·003) and a trend towards increased endothelium-dependent vasodilation following FVPD consumption (P= 0·061). Overall, FVPD consumption significantly increased plasma vitamin C and total nitrate/nitrite concentrations, with a trend towards increased endothelium-dependent vasodilation. Puréed F&V products are useful vehicles for increasing micronutrient status, plasma antioxidant capacity and in vivo NO generation, which may contribute to CVD risk reduction.
A predominantly plant-based diet reduces the risk for development of several chronic diseases. It is often assumed that antioxidants contribute to this protection, but results from intervention trials with single antioxidants administered as supplements quite consistently do not support any benefit. Because dietary plants contain several hundred different antioxidants, it would be useful to know the total concentration of electron-donating antioxidants (i.e., reductants) in individual items. Such data might be useful in the identification of the most beneficial dietary plants. We have assessed systematically total antioxidants in a variety of dietary plants used worldwide, including various fruits, berries, vegetables, cereals, nuts and pulses. When possible, we analyzed three or more samples of dietary plants from three different geographic regions in the world. Total antioxidants was assessed by the reduction of Fe(3+) to Fe(2+) (i.e., the FRAP assay), which occurred rapidly with all reductants with half-reaction reduction potentials above that of Fe(3+)/Fe(2+). The values, therefore, expressed the corresponding concentration of electron-donating antioxidants. Our results demonstrated that there is more than a 1000-fold difference among total antioxidants in various dietary plants. Plants that contain most antioxidants included members of several families, such as Rosaceae (dog rose, sour cherry, blackberry, strawberry, raspberry), Empetraceae (crowberry), Ericaceae (blueberry), Grossulariaceae (black currant), Juglandaceae (walnut), Asteraceae (sunflower seed), Punicaceae (pomegranate) and Zingiberaceae (ginger). In a Norwegian diet, fruits, berries and cereals contributed 43.6%, 27.1% and 11.7%, respectively, of the total intake of plant antioxidants. Vegetables contributed only 8.9%. The systematic analysis presented here will facilitate research into the nutritional role of the combined effect of antioxidants in dietary plants.
Broccoli consumption may reduce the risk of various cancers and many broccoli supplements are now available. The bioavailability and excretion of the mercapturic acid pathway metabolites isothiocyanates after human consumption of broccoli supplements has not been tested. Two important isothiocyanates from broccoli are sulforaphane and erucin. We employed a cross-over study design in which 12 subjects consumed 40 grams of fresh broccoli sprouts followed by a 1 month washout period and then the same 12 subjects consumed 6 pills of a broccoli supplement. As negative controls for isothiocyanate consumption four additional subjects consumed alfalfa sprouts during the first phase and placebo pills during the second. Blood and urine samples were collected for 48 hours during each phase and analyzed for sulforaphane and erucin metabolites using LC-MS/MS. The bioavailability of sulforaphane and erucin is dramatically lower when subjects consume broccoli supplements compared to fresh broccoli sprouts. The peaks in plasma concentrations and urinary excretion were also delayed when subjects consumed the broccoli supplement. GSTP1 polymorphisms did not affect the metabolism or excretion of sulforaphane or erucin. Sulforaphane and erucin are able to interconvert in vivo and this interconversion is consistent within each subject but variable between subjects. This study confirms that consumption of broccoli supplements devoid of myrosinase activity does not produce equivalent plasma concentrations of the bioactive isothiocyanate metabolites compared to broccoli sprouts. This has implications for people who consume the recommended serving size (1 pill) of a broccoli supplement and believe they are getting equivalent doses of isothiocyanates.
Objectives. We considered the relationship between an urban adult population's fruit and vegetable consumption and several selected social and psychological processes, beneficial aesthetic experiences, and garden participation. Methods. We conducted a population-based survey representing 436 residents across 58 block groups in Denver, Colorado, from 2006 to 2007. We used multilevel statistical models to evaluate the survey data. Results. Neighborhood aesthetics, social involvement, and community garden participation were significantly associated with fruit and vegetable intake. Community gardeners consumed fruits and vegetables 5.7 times per day, compared with home gardeners (4.6 times per day) and nongardeners (3.9 times per day). Moreover, 56% of community gardeners met national recommendations to consume fruits and vegetables at least 5 times per day, compared with 37% of home gardeners and 25% of nongardeners. Conclusions. Our study results shed light on neighborhood processes that affect food-related behaviors and provides insights about the potential of community gardens to affect these behaviors. The qualities intrinsic to community gardens make them a unique intervention that can narrow the divide between people and the places where food is grown and increase local opportunities to eat better.
Background/Objectives Vegans and to a lesser extent vegetarians have low average circulating concentrations of vitamin B12; however, the relation between factors such as age or time on these diets and vitamin B12 concentrations is not clear. The objectives were to investigate differences in serum vitamin B12 and folate concentrations between omnivores, vegetarians and vegans and to ascertain whether vitamin B12 concentrations differed by age and time on the diet. Subjects/Methods A cross-sectional analysis involving 689 men (226 omnivores, 231 vegetarians and 232 vegans) from the European Prospective Investigation into Cancer and Nutrition Oxford cohort. Results Mean serum vitamin B12 was highest among omnivores (281, 95% CI: 270-292 pmol/l), intermediate in vegetarians (182, 95% CI: 175-189 pmol/l), and lowest in vegans (122, 95% CI: 117-127 pmol/l). Fifty-two percent of vegans, 7% of vegetarians and one omnivore were classified as vitamin B12 deficient (defined as serum vitamin B12 < 118 pmol/l). There was no significant association between age or duration of adherence to a vegetarian or a vegan diet and serum vitamin B12. In contrast, folate concentrations were highest among vegans, intermediate in vegetarians, and lowest in omnivores, but only two men (both omnivores) were categorised as folate deficient (defined as serum folate < 6.3 nmol/l). Conclusion Vegans have lower vitamin B12 concentrations, but higher folate concentrations, than vegetarians and omnivores. Half of the vegans were categorised as vitamin B12 deficient and would be expected to have a higher risk of developing clinical symptoms related to vitamin B12 deficiency.
Human beings evolved on a diet that was balanced in the omega-6 and omega-3 polyunsaturated fatty acids (PUFA), and was high in antioxidants. Edible wild plants provide alpha-linolenic acid (ALA) and higher amounts of vitamin E and vitamin C than cultivated plants. In addition to the antioxidant vitamins, edible wild plants are rich in phenols and other compounds that increase their antioxidant capacity. It is therefore important to systematically analyze the total antioxidant capacity of wild plants and promote their commercialization in both developed and developing countries. The diets of Western countries have contained increasingly larger amounts of linoleic acid (LA), which has been promoted for its cholesterol-lowering effect. It is now recognized that dietary LA favors oxidative modification of low density lipoprotein (LDL) cholesterol and increases platelet response to aggregation. In contrast, ALA intake is associated with inhibitory effects on the clotting activity of platelets, on their response to thrombin, and on the regulation of arachidonic acid (AA) metabolism. In clinical studies, ALA contributed to lowering of blood pressure, and a prospective epidemiological study showed that ALA is inversely related to the risk of coronary heart disease in men. Dietary amounts of LA as well as the ratio of LA to ALA appear to be important for the metabolism of ALA to longer-chain omega-3 PUFAs. Relatively large reserves of LA in body fat. as are found in vegans or in the diet of omnivores in Western societies, would tend to slow down the formation of long-chain omega-3 fatty acids from ALA. Therefore, the role of ALA in human nutrition becomes important in terms of long-term dietary intake. One advantage of the consumption of ALA over omega-3 fatty acids from fish is that the problem of insufficient vitamin E intake does not exist with high intake of ALA from plant sources.
It has been demonstrated that nitrates are reduced to nitrites in humans, possibly through bacterial activity. Nitrites, together with ubiquitous amines, can lead to an in-vivo synthesis of carcinogenic nitrosamines. The average daily intake of nitrates depends upon the amount of vegetables consumed and on the nitrate concentration in drinking water. Agricultural practices play an important part in the concentration of nitrate in both water and vegetables. If nitrate is taken up by the plant and not metabolised to amino acids, proteins or nucleic acids, it is stored in cell vacuoles as a reserve. However, with an over-supply of nitrate relative to possible photosynthesis, this stored nitrate is still present at harvest and leads to high concentrations in plant tissue. The nitrate content in plants also depends upon other factors, such as plant variety (cultivar), kind and amount of fertiliser, time of harvest and environmental factors such as light intensity, temperature, etc. It is suggested that we should try to meet the recommendations of toxicologists who believe a dramatic reduction nitrate intake for humans is necessary. It has been demonstrated that modern biological-organic farming methods clearly lead both to lower leaching of nitrates and to lower nitrate content in vegetables. Since no synthetic fungicides are used in this farming method, problems with the reaction of metabolites of such products and nitrites e.g. to highly cancerogenic and multigenic nitroso-ethylenethiourea do not exist.
Objective To evaluate whether intake of protein from animal and vegetable origin is associated with ovulatory infertility. Study Design 18,555 married women without a history of infertility were followed as they attempted a pregnancy or became pregnant during an eight year period. Dietary assessments were related to the incidence of ovulatory infertility. Results During follow-up, 438 women reported ovulatory infertility. The multivariate-adjusted relative risk [RR] (95% CI; P, trend) of ovulatory infertility comparing the highest to the lowest quintile of animal protein intake was 1.39 (1.01 – 1.90; 0.03). The corresponding RR (95% CI; P, trend) for vegetable protein intake was 0.78 (0.54 – 1.12; 0.07). Further, consuming 5% of total energy intake as vegetable protein rather than as animal protein was associated with a more than 50% lower risk of ovulatory infertility (P = 0.007). Conclusions Replacing animal sources of protein with vegetable sources of protein may reduce ovulatory infertility risk.
Epidemiological studies find that whole-grain intake is protective against cancer, CVD, diabetes, and obesity. Despite recommendations to consume three servings of whole grains daily, usual intake in Western countries is only about one serving/d. Whole grains are rich in nutrients and phytochemicals with known health benefits. Whole grains have high concentrations of dietary fibre, resistant starch, and oligosaccharides. Whole grains are rich in antioxidants including trace minerals and phenolic compounds and these compounds have been linked to disease prevention. Other protective compounds in whole grains include phytate, phyto-oestrogens such as lignan, plant stanols and sterols, and vitamins and minerals. Published whole-grain feeding studies report improvements in biomarkers with whole-grain consumption, such as weight loss, blood-lipid improvement, and antioxidant protection. Although it is difficult to separate the protective properties of whole grains from dietary fibre and other components, the disease protection seen from whole grains in prospective epidemiological studies far exceeds the protection from isolated nutrients and phytochemicals in whole grains.
We prospectively examined fruit and vegetable intake in relation to cognitive function and decline among aging women. Participants were followed from in 1976 with biennial questionnaires, and food frequency questionnaires were administered in 1984, 1986, and every 4 years thereafter. From 1995 to 2001, we administered, by telephone, six cognitive tests measuring general cognition, verbal memory, category fluency, and working memory. We repeated assessments two years later for 13,388 women (>90% follow-up). We averaged dietary intakes from 1984 through the first cognitive assessment, and used linear regression to obtain multivariable-adjusted mean differences in performance and decline in performance across intake levels. Fruits were not associated with cognition or cognitive decline. However, total vegetable intake was significantly associated with less decline. Specifically, on a global score combining all tests, women in the highest quintile of cruciferous vegetables declined slower (by 0.04 unit; 95% confidence interval, 0.003, 0.07; p trend = 0.1) compared with the lowest quintile. Women consuming the most green leafy vegetables also experienced slower decline than women consuming the least amount (by 0.05 unit; 95% confidence interval, 0.02, 0.09; p trend < 0.001). These mean differences were equivalent to those observed for women about 1 to 2 years apart in age.
The consequences of a change from a mixed to a lactovegetarian diet for 12 mo on trace element concentrations in plasma, hair, urine, and feces were studied in 16 women and 4 men. After the diet shift, intakes of zinc and magnesium did not change but that of selenium decreased by 40%. Three months after the diet shift, plasma and hair concentrations of zinc, copper, and selenium had decreased but those of magnesium had increased and the concentrations of mercury, lead, and cadmium in hair were lower. Also, the excretion of zinc, copper, and magnesium in urine, and that of selenium in urine and feces had decreased. Only small changes occurred during the remaining lactovegetarian-diet period. Three years later trace element concentrations had reverted towards baseline concentrations; copper values were similar to baseline concentrations but data for magnesium were slightly higher, and more complex patterns were observed for zinc and selenium. It is concluded that a shift to a lactovegetarian diet changes trace element status.
There is strong evidence indicating that elevated plasma total homocysteine (tHcy) levels are a major independent biomarker and/or a contributor to chronic conditions, such as CVD. A deficiency of vitamin B₁₂ can elevate homocysteine. Vegetarians are a group of the population who are potentially at greater risk of vitamin B₁₂ deficiency than omnivores. This is the first systematic review and meta-analysis to appraise a range of studies that compared the homocysteine and vitamin B₁₂ levels of vegetarians and omnivores. The search methods employed identified 443 entries, from which, by screening using set inclusion and exclusion criteria, six eligible cohort case studies and eleven cross-sectional studies from 1999 to 2010 were revealed, which compared concentrations of plasma tHcy and serum vitamin B₁₂ of omnivores, lactovegetarians or lacto-ovovegetarians and vegans. Of the identified seventeen studies (3230 participants), only two studies reported that vegan concentrations of plasma tHcy and serum vitamin B₁₂ did not differ from omnivores. The present study confirmed that an inverse relationship exists between plasma tHcy and serum vitamin B₁₂, from which it can be concluded that the usual dietary source of vitamin B₁₂ is animal products and those who choose to omit or restrict these products are destined to become vitamin B₁₂ deficient. At present, the available supplement, which is usually used for fortification of food, is the unreliable cyanocobalamin. A well-designed study is needed to investigate a reliable and suitable supplement to normalise the elevated plasma tHcy of a high majority of vegetarians. This would fill the gaps in the present nutritional scientific knowledge.
BACKGROUND: There are no long-term prospective studies assessing the impact of the vegan diet on vitamin B-12 (B-12) status. Many vegans take B-12 supplements irregularly or refuse to adopt them at all, considering them to be "unnatural" products. The use of B-12 fortified food may be an alternative. Therefore, we aimed to estimate the long-term effect of a vegan diet on serum B-12 concentrations in healthy omnivore adults, comparing the influence of natural products consumption and B-12 fortified food. MATERIAL AND METHODS: A five year prospective study was carried out comprising 20 omnivore healthy adult subjects, who moved to strict vegan diet for 5 years. Ten volunteers followed vegan diet based entirely on natural products, while the remaining ten subjects consumed food fortified in B-12. In all subjects serum vitamin B-12 concentration was determined before and 6, 12, 24 and 60 months after the implementation of the diet. RESULTS: A significant decrease (p < 0.0002) of serum B-12 concentrations in the whole studied group was noted after 60 months of vegan diet. However, observed changes were in fact limited to the subgroup consuming exclusively natural products (p < 0.0001). CONCLUSIONS: Transition from omnivore to vegan diet is associated with the risk of vitamin B-12 deficiency. B-12 fortified products might constitute a valuable alternative in vegans refusing to take vitamin supplements.
The effects of the chemical composition of fruit juices and fruit on the absorption of iron from a rice (Oryza sativa) meal were measured in 234 parous Indian women, using the erythrocyte utilization of radioactive Fe method. The corrected geometric mean Fe absorptions with different juices varied between 0.040 and 0.129, with the variation correlating closely with the ascorbic acid contents of the juices (rs 0.838, P less than 0.01). Ascorbic acid was not the only organic acid responsible for the promoting effects of citrus fruit juices on Fe absorption. Fe absorption from laboratory 'orange juice' (100 ml water, 33 mg ascorbic acid and 750 mg citric acid) was significantly better than that from 100 ml water and 33 mg ascorbic acid alone (0.097 and 0.059 respectively), while Fe absorption from 100 ml orange juice (28 mg ascorbic acid) was better than that from 100 ml water containing the same amount of ascorbic acid (0.139 and 0.098 respectively). Finally, Fe absorption from laboratory 'lemon juice' (100 ml orange juice and 4 g citric acid) was significantly better than that from 100 ml orange juice (0.226 and 0.166 respectively). The corrected geometric mean Fe absorption from the rice meal was 0.025. Several fruits had little or no effect on Fe absorption from the meal (0.013-0.024). These included grape (Vitis vinifera), peach (Prunus persica), apple (Malus sylvestris) and avocado pear (Persea americana). Fruit with a mild to moderate enhancing effect on Fe absorption (0.031-0.088) included strawberry (Fragaria sp.) (uncorrected values), plum (Prunus domestica), rhubarb (Rheum rhaponticum), banana (Musa cavendishii), mango (Mangifera indica), pear (Pyrus communis), cantaloup (Cucumis melo) and pineapple (Ananas comosus) (uncorrected values). Guava (Psidium guajava) and pawpaw (Carica papaya) markedly increased Fe absorption (0.126-0.293). There was a close correlation between Fe absorption and the ascorbic acid content of the fruits tested (rs 0.738, P less than 0.0001). There was also a weaker but significant correlation with the citric acid content (rs 0.55, P less than 0.03). Although this may have reflected a direct effect of citric acid on Fe absorption, it should be noted that fruits containing citric acid also contained ascorbic acid (rs 0.70, P less than 0.002).(ABSTRACT TRUNCATED AT 400 WORDS)
Context: Adequate dietary iodine is required for normal thyroid function. The iodine status and thyroid function of U.S. vegetarians and vegans have not been previously studied. Environmental perchlorate and thiocyanate (inhibitors of thyroid iodine uptake) exposures may adversely affect thyroid function. Objective: The objective of the study was to assess the iodine status and thyroid function of U.S. vegetarians (consume plant based products, eggs, milk; abstain from meat, poultry, fish, shellfish) and vegans (avoid all animal products) and whether these may be affected by environmental perchlorate and thiocyanate exposures. Design and Setting: This was a cross-sectional assessment of urinary iodine, perchlorate, and thiocyanate concentrations and serum thyroid function in Boston-area vegetarians and vegans. Subjects: One hundred forty-one subjects (78 vegetarians, 63 vegans) were recruited; one vegan was excluded. Results: Median urinary iodine concentration of vegans (78.5 μg/liter; range 6.8–964.7 μg/liter) was lower than vegetarians (147.0 μg/liter; range 9.3–778.6 μg/liter) (P < 0.01). Adjusted for cigarette smoking (confirmed by urinary cotinine levels) and thiocyanate-rich food consumption, median urinary thiocyanate concentration of vegans (630 μg/liter; range 108-3085 μg/liter) was higher than vegetarians (341 μg/liter; range 31–1963 μg/liter) (P < 0.01). There were no between-group differences in urinary perchlorate concentrations (P = 0.75), TSH (P = 0.46), and free T4 (P = 0.77). Urinary iodine, perchlorate, and thiocyanate levels were not associated with TSH (P = 0.59) or free T4 (P = 0.14), even when adjusted for multiple variables. Conclusions: U.S. vegetarians are iodine sufficient. U.S. vegans may be at risk for low iodine intake, and vegan women of child-bearing age should supplement with 150 μg iodine daily. Environmental perchlorate and thiocyanate exposures are not associated with thyroid dysfunction in these groups.
Plants are rich natural sources of antioxidants in addition to other nutrients. Interventions and cross sectional studies on subjects consuming uncooked vegan diet called living food (LF) have been carried out. We have clarified the efficacy of LF in rheumatoid diseases as an example of a health problem where inflammation is one of the main concerns. LF is an uncooked vegan diet and consists of berries, fruits, vegetables and roots, nuts, germinated seeds and sprouts, i.e. rich sources of carotenoids, vitamins C and E. The subjects eating LF showed highly increased levels of beta and alfa carotenes, lycopen and lutein in their sera. Also the increases of vitamin C and vitamin E (adjusted to cholesterol) were statistically significant. As the berry intake was 3-fold compared to controls the intake of polyphenolic compounds like quercetin, myricetin and kaempherol was much higher than in the omnivorous controls. The LF diet is rich in fibre, substrate of lignan production, and the urinary excretion of polyphenols like enterodiol and enterolactone as well as secoisolaricirecinol were much increased in subjects eating LF. The shift of fibromyalgic subjects to LF resulted in a decrease of their joint stiffness and pain as well as an improvement of their self-experienced health. The rheumatoid arthritis patients eating the LF diet also reported similar positive responses and the objective measures supported this finding. The improvement of rheumatoid arthritis was significantly correlated with the day-to-day fluctuation of subjective symptoms. In conclusion the rheumatoid patients subjectively benefited from the vegan diet rich in antioxidants, lactobacilli and fibre, and this was also seen in objective measures.
A study is reported in which the prevalence of symptomless diverticular disease of the colon is related to the consumption of dietary fibre in vegetarians and non-vegetarians. Vegetarians had a significantly higher mean fibre intake (41.5 g/day) than non-vegetarians (21.4 g/day). Diverticular disease was commoner in non-vegetarians (33%) than in vegetarians (12%). Comparison of subjects with and without diverticular disease in the vegetarian and non-vegetarian groups provided some further evidence that a low intake of cereal fibre is associated with the presence of diverticular disease.
Brassica vegetables contain a diverse range of phytochemicals with biological properties such as antioxidant and anticancer activity. However, knowledge about how biological activities are affected by processing is lacking. A green cultivar and a red cultivar of curly kale were evaluated for water/methanol-soluble phytochemicals before and after processing involving blanching, freeze storage, and boil-in-bag heat treatment. In both kale cultivars, processing resulted in a significant decrease of total phenolics, antioxidant capacity, and content and distribution of flavonols, anthocyanins, hydroxycinnamic acids, glucosinolates, and vitamin C. Interestingly, the red curly kale cultivar had a higher capacity to withstand thermal loss of phytochemicals. The extracts of both green and red curly kale inhibited the cell proliferation of three human colon cancer cell lines (Caco-2, HT-29, and HCT 116). However, extracts from fresh plant material had a significantly stronger antiproliferative effect than extracts from processed plant material.
This case-control study examined different food groups in relation to breast cancer. Between 2002 and 2004, 437 cases and 922 controls matched according to age and area of residence were interviewed. Diet was measured by a validated food frequency questionnaire. Adjusted odds ratios (Ors) were computed across levels of various dietary intakes identified by two methods: the "classical" and the "spline" methods. Neither of the 2 methods found an association between total fruit and vegetable consumption and breast cancer. Results of the 2 methods showed a nonsignificant decreased association with cooked vegetables intake as well as legumes and fish consumption. Whereas the spline method showed no association, the classical method showed significant associations related to the lowest consumption of raw vegetables or dairy products and breast cancer risk: Adjusted OR for raw vegetable consumption between (67.4 and 101.3 g/day) vs. (< 67.4 g/day) was 0.63 [95% confidence interval (CI) = 0.43-0.93]. Adjusted OR for dairy consumption between (134.3 and 271.2 g/day) vs. (< 134.3 g/day) was 1.57 (95% CI = 1.06-2.32). However, the overall results were not consistent. Compared to the classical method, the use of the spline method showed a significant association for cereal, meat, and olive oil. Cereal and olive oil were inversely associated with breast cancer risk. Breast cancer risk increased by 56% for each additional 100 g/day of meat consumption. Studies using novel methodological techniques are needed to confirm the dietary threshold responsible for changes in breast cancer risk. New approaches that consist in analyzing dietary patterns rather than dietary food are necessary.
The effects of different polyphenol-containing beverages on Fe absorption from a bread meal were estimated in adult human subjects from the erythrocyte incorporation of radio-Fe. The test beverages contained different polyphenol structures and were rich in either phenolic acids (chlorogenic acid in coffee), monomeric flavonoids (herb teas, camomile (Matricaria recutita L.), vervain (Verbena officinalis L.), lime flower (Tilia cordata Mill.), pennyroyal (Mentha pulegium L.) and peppermint (Mentha piperita L.), or complex polyphenol polymerization products (black tea and cocoa). All beverages were potent inhibitors of Fe absorption and reduced absorption in a dose-dependent fashion depending on the content of total polyphenols. Compared with a water control meal, beverages containing 20-50 mg total polyphenols/serving reduced Fe absorption from the bread meal by 50-70%, whereas beverages containing 100-400 mg total polyphenols/serving reduced Fe absorption by 60-90%. Inhibition by black tea was 79-94%, peppermint tea 84%, pennyroyal 73%, cocoa 71%, vervain 59%, lime flower 52% and camomile 47%. At an identical concentration of total polyphenols, black tea was more inhibitory than cocoa, and more inhibitory than herb teas camomile, vervain, lime flower and pennyroyal, but was of equal inhibition to peppermint tea. Adding milk to coffee and tea had little or no influence on their inhibitory nature. Our findings demonstrate that herb teas, as well as black tea, coffee and coca can be potent inhibitors of Fe absorption. This property should be considered when giving dietary advice in relation to Fe nutrition.
We examined the resting metabolic rate (RMR) and sympathetic nervous system activity of young male vegetarians (n = 17) and nonvegetarians (n = 40). Subjects were characterized for RMR by indirect calorimetry, norepinephrine kinetics from infusions of tritiated norepinephrine, energy and macronutrient intake from a 3-day food diary, and body composition by underwater weighing. Vegetarians reported a greater relative intake of carbohydrates (62% +/- 5% v 51% +/- 6%, P < .01) and a lower relative intake of fat (25% +/- 5% v 33% +/- 6%, P < .01) than nonvegetarians, whereas no differences were observed in daily energy intake, body composition, or maximal aerobic capacity (VO2max) between groups. Vegetarians exhibited an 11% higher absolute RMR (1.29 +/- 0.15 v 1.16 +/- 0.13 kcal/min, P < .01), a higher plasma concentration of norepinephrine (216 +/- 33 v 165 +/- 18 pg/mL, P < .01), and a greater norepinephrine appearance rate (0.50 +/- 0.08 v 0.36 +/- 0.09 micrograms/min, P < .01) than nonvegetarians. After statistically controlling for differences in relative amounts of carbohydrate and fat in the diet and for norepinephrine concentrations, no significant differences in adjusted RMR between vegetarians and nonvegetarians were noted. These results suggest that the higher RMR observed in young male vegetarians is partially mediated by differences in dietary macronutrient composition and increased sympathetic nervous system activity.
Chickpea (Cicer arietinum L.) is an important pulse crop grown and consumed all over the world, especially in the Afro-Asian countries. It is a good source of carbohydrates and protein, and protein quality is considered to be better than other pulses. Chickpea has significant amounts of all the essential amino acids except sulphur-containing amino acids, which can be complemented by adding cereals to the daily diet. Starch is the major storage carbohydrate followed by dietary fibre, oligosaccharides and simple sugars such as glucose and sucrose. Although lipids are present in low amounts, chickpea is rich in nutritionally important unsaturated fatty acids such as linoleic and oleic acids. β-Sitosterol, campesterol and stigmasterol are important sterols present in chickpea oil. Ca, Mg, P and, especially, K are also present in chickpea seeds. Chickpea is a good source of important vitamins such as riboflavin, niacin, thiamin, folate and the vitamin A precursor β-carotene. As with other pulses, chickpea seeds also contain anti-nutritional factors which can be reduced or eliminated by different cooking techniques. Chickpea has several potential health benefits, and, in combination with other pulses and cereals, it could have beneficial effects on some of the important human diseases such as CVD, type 2 diabetes, digestive diseases and some cancers. Overall, chickpea is an important pulse crop with a diverse array of potential nutritional and health benefits.
BACKGROUND/AIM: A vegetarian diet is known to prevent a series of diseases but may influence the balance of carbohydrate and fat metabolism as well as collagen synthesis. This study compares expression patterns of relevant genes in oral mucosa of omnivores and vegetarians. METHODS: Quantitative reverse transcriptase polymerase chain reaction was applied for analysis of mRNA levels from carnitine transporter OCTN2, hepatic CPT1A and nonhepatic CPT1B isoforms of carnitine palmitoyltransferase and collagen (CCOL2A1) in oral mucosa. RESULTS: Compared with volunteers with traditional eating habits, carbohydrate consumption was significantly higher (+22%) in vegetarians. This was associated with a significant stimulation of CPT1A (+50%) and OCTN2 (+10%) and a lowered collagen synthesis (-10%). CONCLUSION: These novel findings provide further insight into the association of a changed fat metabolism and reduced collagen synthesis in vegetarians, which could also play a role in the aging process. Copyright 2008 S. Karger AG, Basel.
We reviewed data from six cohort studies and approximately 40 case-control studies on the relation between selected aspects of diet and the risk of oral and pharyngeal cancer. Fruit and vegetables were inversely related to the risk: the pooled relative risk (RR) for high vegetable consumption was 0.65 from three cohort studies on upper aerodigestive tract cancers and 0.52 from 18 case-control studies of oral and pharyngeal cancer; corresponding RRs for high fruit consumption were 0.78 and 0.55. beta-carotene, vitamin C and selected flavonoids have been inversely related to the risk, but it is difficult to disentangle their potential effect from that of fruit and vegetables. Whole grain, but not refined grain, intake was also favorably related to oral cancer risk. The results were not consistent with reference to other foods beverages, and nutrients, but it is now possible to exclude a strong relation between these foods and oral and pharyngeal cancer risk. In western countries, selected aspects of diet may account for 20-25% of oral and pharyngeal cancer, and the population attributable risk increases to 85-95% when tobacco and alcohol consumption are also considered.
Much effort has been focused on sanitation of fresh produce at the commercial level; however, few options are available to the consumer. The purpose of this study was to determine the efficacy of different cleaning methods in reducing bacterial contamination on fresh produce in a home setting. Lettuce, broccoli, apples, and tomatoes were inoculated with Listeria innocua and then subjected to combinations of the following cleaning procedures: (i) soak for 2 min in tap water, Veggie Wash solution, 5% vinegar solution, or 13% lemon solution and (ii) rinse under running tap water, rinse and rub under running tap water, brush under running tap water, or wipe with wet/dry paper towel. Presoaking in water before rinsing significantly reduced bacteria in apples, tomatoes, and lettuce, but not in broccoli. Wiping apples and tomatoes with wet or dry paper towel showed lower bacterial reductions compared with soaking and rinsing procedures. Blossom ends of apples were more contaminated than the surface after soaking and rinsing; similar results were observed between flower section and stem of broccoli. Reductions of L. innocua in both tomatoes and apples (2.01 to 2.89 log CFU/g) were more than in lettuce and broccoli (1.41 to 1.88 log CFU/g) when subjected to same washing procedures. Reductions of surface contamination of lettuce after soaking in lemon or vinegar solutions were not significantly different (P > 0.05) from lettuce soaking in cold tap water. Therefore, educators and extension workers might consider it appropriate to instruct consumers to rub or brush fresh produce under cold running tap water before consumption.