369 research outputs found
The Mediterranean Way of Eating
Scientific evidence accumulated over decades validates the idea that a plant-based dietary pattern, such as the traditional Mediterranean way of eating, promotes health and plays an important role in risk reduction and prevention of several chronic diseases. One of the great advantages of the Mediterranean diet is that it can be easily adopted by other cultures because it is flexible and highly palatable. The Mediterranean Way of Eating: Evidence for Chronic Disease Prevention and Weight Management offers evidence-based information about an enjoyable, healthy way of eating that has stood the test of time, along with practical suggestions for incorporating the Mediterranean diet into your daily life. The first part of the book provides a brief history of the Mediterranean region and its different dietary influences. It discusses shared and unique foods in the coastal regions, and recent influences of processed foods and fast foods. It also presents scientific information on critical nutrients (macronutrients, vitamins, minerals, phytochemicals, antioxidants, and fiber) in foods found in the Mediterranean diets, how they function in the body, and why they are essential to health. The authors review the major chronic diseases, including obesity, type 2 diabetes, cardiovascular diseases, and certain cancers, and examine how a Mediterranean-style diet may help reduce risk or prevent these diseases. The second part of the book addresses the protective effects of foods and food components, discussing how Mediterranean diets may confer health benefits for reducing disease risk and managing weight. It examines the evidence-based health benefits for each of the food groupsâsuch as fruits, vegetables, grains, fish, meat, dairy products, plus alcoholâalong with suggestions for using the foods as part of a healthy diet. The last part of the book focuses on how to move toward a Mediterranean-style diet in your own life, eating at home or dining out, offering effective strategies for implementing the dietary changes
Risk of High Dietary Calcium for Arterial Calcification in Older Adults
Concern has recently arisen about the potential adverse effects of excessive calcium intakes, i.e., calcium loading from supplements, on arterial calcification and risks of cardiovascular diseases (CVD) in older adults. Published reports that high calcium intakes in free-living adults have relatively little or no beneficial impact on bone mineral density (BMD) and fracture rates suggest that current recommendations of calcium for adults may be set too high. Because even healthy kidneys have limited capability of eliminating excessive calcium in the diet, the likelihood of soft-tissue calcification may increase in older adults who take calcium supplements, particularly in those with age or disease-related reduction in renal function. The maintenance of BMD and bone health continues to be an important goal of adequate dietary calcium consumption, but eliminating potential risks of CVDs from excessive calcium intakes needs to be factored into policy recommendations for calcium by adults
Intakes of Calcium and Phosphorus and Calculated Calcium-to-Phosphorus Ratios of Older Adults: NHANES 2005â2006 Data
Background: High intakes of dietary phosphorus (P), relative to calcium (Ca) intake, are associated with a lower calcium:phosphorus ratio (Ca:P) ratio which potentially has adverse health effects, including arterial calcification, bone loss, and death. A substantial percentage of older adults (50 to 70 and 71 plus years) who have a higher risk of fracture rate than younger adults typically have low intakes of dietary Ca that are dominated by higher intakes of dietary P from natural and fortified foods, and lower Ca:P ratios than desirable. Objective: This investigation was undertaken to examine Ca and P intakes and the resulting Ca:P ratios (by mass) across gender and older adult age groups, using data from the National Health and Nutrition Examination Survey (NHANES) 2005â2006. Design: NHANES data are based on a cross-sectional sample of the non-institutionalized United States (US) population within various regions. This sample is selected to be representative of the entire US population at all ages. National Cancer Institute (NCI) methods and SAS survey procedures were used for analyses. Ca:P ratios were calculated using total Ca from both foods and supplements, whereas P intakes were calculated from food composition values and supplements. The amounts of P additives in processed foods are not available. Results: Mean Ca and P intakes demonstrated lower intakes of Ca and higher intakes of P compared to current Recommended Dietary Allowances (RDAs). The Ca:P ratios in older male and female adults were influenced by both low-Ca and high-P dietary consumption patterns. Conclusions: Both low total Ca intakes and high P amounts contribute to lower Ca:P ratios, i.e., ~0.7:1.0, in the consumption patterns of older adults than is recommended by the RDAs, i.e., ~1.5:1.0. Whether Ca:P ratios lower than recommended contribute to increased risk of bone loss, arterial calcification, and all-cause mortality cannot be inferred from these data. Additional amounts of chemical P additives in the food supply may actually reduce even further the Ca:P ratios of older adults of both genders, but, without P additive data from the food industry, calculation of more precise ratios from NHANES 2005â2006 data is not possible
Calcium and vitamin D intakes may be positively associated with brain lesions in depressed and nondepressed elders
Studies indicate that diet and vascular calcification may be related to the occurrence of brain lesions, although the importance of dietary calcium and vitamin D has not been investigated. The objective of this study was to test the hypothesis that calcium and vitamin D intakes would be positively associated with brain lesion volumes in elderly individuals with and without late-life depression. A cross sectional study was performed as part of a longitudinal clinical study of late-life depression. Calcium and vitamin D intakes were assessed in 232 elderly subjects (95 with current or prior depression, 137 without depression) using a Block 1998 food frequency questionnaire. Calcium, vitamin D, and kilocalorie intake were determined. Brain lesion volumes were calculated from magnetic resonance imaging scan. Subjects were age 60 years or over. Calcium and vitamin D intakes were significantly and positively correlated with brain lesion volume (p < 0.05 and p < 0.001, respectively). In two separate multivariable models, controlling for age, hypertension, diabetes, heart disease, group (depression/comparison), lesion load (high/low), and total kilocalories, these positive associations remained significant (p<0.05 for calcium; p < 0.001 for vitamin D). In conclusion, calcium and vitamin D consumption were associated with brain lesions in elderly subjects, even after controlling for potentially explanatory variables. These associations may be due to vascular calcification or other mechanism. The possibility of adverse effects of high intakes of calcium and vitamin D needs to be further explored in longitudinal studies of elderly subjects
Effects of phyto-oestrogens on tissues
Recent investigations on the effects of phyto-oestrogens on various tissues have revealed that these diverse molecules may improve human health, particularly by protecting against certain chronic diseases. After a brief examination of the food sources, structures, and general cellular actions of the major phyto-oestrogens, current research findings on cardiovascular disease, skeletal tissues, and reproductive cancers are reviewed. Phyto-oestrogen concentrations in blood may be maintained at high levels in those consuming soyabean (Glycine max)-based food daily at several meals and exert their effects on target cells through either genomic effects via the classical oestrogen receptors or non-genomic effects mediated by membrane-bound oestrogen receptors or other cellular proteins. The expression of oestrogen receptor (OR) subtypes alpha (a) and beta (beta) varies across tissues, and cells that preferentially express OR-beta, which may include bone cells, are more likely to respond to phyto-oestrogens. Conversely, reproductive tissues contain relatively more OR-a and may, thus, be differently affected by phyto-oestrogens. Soyabean phyto-oestrogens appear to prevent the progression of atherosclerosis through multiple interactions, including lowering of plasma lipids and lipoproteins, increased vasodilatation and, possibly, decreased activation of blood platelets and vascular smooth muscle cells. However, a favourable impact on cardiovascular disease morbidity and mortality by a soyabean-enriched western-type diet remains to be shown, and unresolved questions remain regarding dose and form of the phyto-oestrogens in relation to risks and benefits. The isoflavones of soyabean have been shown consistently to have bone-retentive effects in animal studies by several investigators using rodent models, although intakes must be above a relatively high threshold level for a lengthy period of time, and little or no extra benefit is observed with intakes above this threshold level. The reports of modest or no effects on prevention of bone loss in human and non-human primate studies respectively, may be due to the limited doses tested so far. The relationship between soyabean-food intake and cancer risk has been more extensively investigated than for any other disease, but with less certainty about the benefits of long-term consumption of phyto-oestrogen-containing foods on prevention of cancer. The observations that breast and prostate cancer rates are lower in Asian countries, where soyabean foods are consumed at high levels, and the high isoflavone content of soyabeans have led to examination of the potential protective effects of phyto-oestrogens. Establishing diet-cancer relationships has proved difficult, in part because of the conflicting data from various studies of effects of soyabean-diets on cancer. Epidemiological evidence, though not impressive, does suggest that soyabean intake reduces breast cancer risk. The isoflavone genistein has a potent effect on breast cancer cells in vitro, and early exposure of animals to genistein has been effective in reducing later development of mammary cancer. Thus, continuous consumption of soyabean foods in early life and adulthood may help explain the low breast cancer mortality rates in Asian countries. Although the evidence for a protective effect against prostate cancer may be slightly more supportive, more research is needed before any firm conclusions can be made about the phyto-oestrogen-cancer linkages
Elevated brain lesion volumes in older adults who use calcium supplements: a cross-sectional clinical observational study
Recent studies have implicated calcium supplements with elevated vascular risk, and therefore these supplements may also relate to the occurrence of brain lesions (or hyperintensities) in older adults. These lesions represent damage to brain tissue that is caused by ischaemia. This cross sectional clinical observational study examined the association between use of calcium-containing dietary supplements and lesion volumes in a sample of 227 older adults (60 years and older). Food and supplemental calcium intakes were assessed with a Block 1998 FFQ; participants with supplemental calcium intakes above zero were categorized as supplement users. Lesion volumes were determined from cranial MRI (1.5 Tesla) using a semi-automated technique; volumes were log-transformed because they were non-normal. An ANCOVA model showed that supplement users had greater lesion volumes than non-users, even after controlling for dietary food calcium, age, sex, race, education, energy intake, depression and hypertension (Calcium supplement use: ÎČ = 0.34, SE = 0.10, F1,217 = 10.98, p = 0.0011). The influence of supplemental calcium use on lesion volume was of similar magnitude to that of hypertension, a well-established risk factor for lesions. Among supplement users, the amount of supplemental calcium was not related to lesion volume (ÎČ = â0.000035, SE = 0.00015, F1,139 = 0.06, p = 0.81). This study indicates that the use of calcium-containing dietary supplements, even low dose supplements, by older adults may be associated with greater lesion volumes. Evaluation of randomised, controlled trials is warranted to determine if this relationship is a causal one
Calcium Intake From Diet and Supplements and the Risk of Coronary Artery Calcification and its Progression Among Older Adults: 10âYear Followâup of the MultiâEthnic Study of Atherosclerosis (MESA)
BACKGROUND: Recent randomized data suggest that calcium supplements may be associated with increased risk of cardiovascular disease (CVD) events. Using a longitudinal cohort study, we assessed the association between calcium intake, from both foods and supplements, and atherosclerosis, as measured by coronary artery calcification (CAC).
METHODS AND RESULTS: We studied 5448 adults free of clinically diagnosed CVD (52% female; aged 45-84Â years) from the Multi-Ethnic Study of Atherosclerosis. Baseline total calcium intake was assessed from diet (using a food frequency questionnaire) and calcium supplements (by a medication inventory) and categorized into quintiles. Baseline CAC was measured by computed tomography, and CAC measurements were repeated in 2742 participants â10Â years later. At baseline, mean calcium intakes across quintiles were 313.3, 540.3, 783.0, 1168.9, and 2157.4Â mg/day. Women had higher calcium intakes than men. After adjustment for potential confounders, among 1567 participants without baseline CAC, the relative risk (RR) of developing incident CAC over 10Â years, by quintile 1 to 5 of calcium intake, were 1 (reference), 0.95 (0.79-1.14), 1.02 (0.85-1.23), 0.86 (0.69-1.05), and 0.73 (0.57-0.93). After accounting for total calcium intake, calcium supplement use was associated with increased risk for incident CAC (RR=1.22 [1.07-1.39]). No relation was found between baseline calcium intake and 10-year changes in log-transformed CAC among those participants with baseline CAC >0.
CONCLUSIONS: High total calcium intake was associated with a decreased risk of incident atherosclerosis over long-term follow-up, particularly if achieved without supplement use. However, calcium supplement use may increase the risk for incident CAC
John Rawls between two enlightenments
John Rawls shares the Enlightenment's commitment to finding moral and political principles which can be reflectively endorsed by all individuals autonomously. He usually presents reflective autonomy in Kantian, rationalist terms: autonomy is identified with the exercise of reason, and principles of justice must be constructed which are acceptable to all on the basis of reason alone. Yet David Hume, Adam Smith and many other Enlightenment thinkers rejected such rationalism, searching instead for principles which can be endorsed by all on the basis of all the faculties of the human psyche, emotion and imagination included. The influence of these sentimentalists on Rawls is clearest in his descriptive moral psychology, but I argue that it is also present in Rawls's understanding of the sources of normativity. Although this debt is obscured by Rawls's explicit "Kantianism," his theory would be strengthened by a greater understanding of its debts to the sentimentalist Enlightenment
First-order cosmological phase transitions in the radiation dominated era
We consider first-order phase transitions of the Universe in the
radiation-dominated era. We argue that in general the velocity of interfaces is
non-relativistic due to the interaction with the plasma and the release of
latent heat. We study the general evolution of such slow phase transitions,
which comprise essentially a short reheating stage and a longer phase
equilibrium stage. We perform a completely analytical description of both
stages. Some rough approximations are needed for the first stage, due to the
non-trivial relations between the quantities that determine the variation of
temperature with time. The second stage, instead, is considerably simplified by
the fact that it develops at a constant temperature, close to the critical one.
Indeed, in this case the equations can be solved exactly, including
back-reaction on the expansion of the Universe. This treatment also applies to
phase transitions mediated by impurities. We also investigate the relations
between the different parameters that govern the characteristics of the phase
transition and its cosmological consequences, and discuss the dependence of
these parameters with the particle content of the theory.Comment: 38 pages, 3 figures; v2: Minor changes, references added; v3: several
typos correcte
LSST: from Science Drivers to Reference Design and Anticipated Data Products
(Abridged) We describe here the most ambitious survey currently planned in
the optical, the Large Synoptic Survey Telescope (LSST). A vast array of
science will be enabled by a single wide-deep-fast sky survey, and LSST will
have unique survey capability in the faint time domain. The LSST design is
driven by four main science themes: probing dark energy and dark matter, taking
an inventory of the Solar System, exploring the transient optical sky, and
mapping the Milky Way. LSST will be a wide-field ground-based system sited at
Cerro Pach\'{o}n in northern Chile. The telescope will have an 8.4 m (6.5 m
effective) primary mirror, a 9.6 deg field of view, and a 3.2 Gigapixel
camera. The standard observing sequence will consist of pairs of 15-second
exposures in a given field, with two such visits in each pointing in a given
night. With these repeats, the LSST system is capable of imaging about 10,000
square degrees of sky in a single filter in three nights. The typical 5
point-source depth in a single visit in will be (AB). The
project is in the construction phase and will begin regular survey operations
by 2022. The survey area will be contained within 30,000 deg with
, and will be imaged multiple times in six bands, ,
covering the wavelength range 320--1050 nm. About 90\% of the observing time
will be devoted to a deep-wide-fast survey mode which will uniformly observe a
18,000 deg region about 800 times (summed over all six bands) during the
anticipated 10 years of operations, and yield a coadded map to . The
remaining 10\% of the observing time will be allocated to projects such as a
Very Deep and Fast time domain survey. The goal is to make LSST data products,
including a relational database of about 32 trillion observations of 40 billion
objects, available to the public and scientists around the world.Comment: 57 pages, 32 color figures, version with high-resolution figures
available from https://www.lsst.org/overvie
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