► Review of the extant literature on vegetarianism. ► Vegetarianism associated with concern for environment, equality, and social justice. ► Health vegetarians concerned primarily with personal ...well-being; ethical vegetarians with welfare of others. ► Women more likely to be vegetarian, express greater concern for animal welfare. ► Calls for a broader investigation of vegetarianism across non-Western cultures.
Vegetarianism, the practice of abstaining from eating meat, has a recorded history dating back to ancient Greece. Despite this, it is only in recent years that researchers have begun conducting empirical investigations of the practices and beliefs associated with vegetarianism. The present article reviews the extant literature, exploring variants of and motivations for vegetarianism, differences in attitudes, values and worldviews between omnivores and vegetarians, as well as the pronounced gender differences in meat consumption and vegetarianism. Furthermore, the review highlights the extremely limited cultural scope of the present data, and calls for a broader investigation across non-Western cultures.
It is assumed that diet influences the composition of gut microbiota, which in turn may affect human health status. This systematic review aimed to summarize associations of a vegan or vegetarian ...diet with the composition of microbiota. A literature search was conducted in PubMed and Embase for eligible human studies with vegan or vegetarian diets as an exposure and microbiota composition as an outcome in healthy adults. Furthermore, data from our cross-sectional study with vegan participants were included. Out of sixteen included studies, six investigated the association between gut microbiota composition in both vegans and in vegetarians, six in vegans and four studies in vegetarians compared to omnivores, respectively. Among 5 different phyla, 28 families, 96 genera and 177 species, Bacteroides, Bifidobacterium and Prevotella were the most reported genera, followed by the species Prevotella copri, Faecalibacterium prausnitzii and Escherichia coli in all diets. No consistent association between a vegan diet or vegetarian diet and microbiota composition compared to omnivores could be identified. Moreover, some studies revealed contradictory results. This result could be due to high microbial individuality, and/or differences in the applied approaches. Standardized methods with high taxonomical and functional resolutions are needed to clarify this issue.
Abstract
The oldest known complex terrestrial vertebrate community included hypercarnivorous varanopids, a successful clade of amniotes with wide geographic and temporal distributions. Little is ...known about their dentition and feeding behaviour, but with the unprecedented number of specimens of the varanopid
Mesenosaurus
from cave deposits in Oklahoma, we show that it exhibited serrations on the tooth crowns, and exceptionally rapid rates of development and reduced longevity relative to other terrestrial amniotes. In contrast, the coeval large apex predator
Dimetrodon
greatly increased dental longevity by increasing thickness and massiveness, whereas herbivores greatly reduced tooth replacement rates and increased dental longevity. Insectivores and omnivores represented the primitive condition and maintained modest replacement rates and longevity. The varied patterns of dental development among these early terrestrial amniotes reveal a hidden aspect of dental complexity in the emerging diverse amniote community, very soon after their initial appearance in the fossil record.
A Pesco-Mediterranean Diet With Intermittent Fasting O’Keefe, James H.; Torres-Acosta, Noel; O’Keefe, Evan L. ...
Journal of the American College of Cardiology,
09/2020, Letnik:
76, Številka:
12
Journal Article
Recenzirano
Odprti dostop
As opportunistic omnivores, humans are evolutionarily adapted to obtain calories and nutrients from both plant and animal food sources. Today, many people overconsume animal products, often-processed ...meats high in saturated fats and chemical additives. Alternatively, strict veganism can cause nutritional deficiencies and predispose to osteopenia, sarcopenia, and anemia. A logical compromise is a plant-rich diet with fish/seafood as principal sources of animal food. This paper reviews cumulative evidence regarding diet and health, incorporating data from landmark clinical trials of the Mediterranean diet and recommendations from recent authoritative guidelines, to support the hypothesis that a Pesco-Mediterranean diet is ideal for optimizing cardiovascular health. The foundation of this diet is vegetables, fruits, nuts, seeds, legumes, whole grains, and extra-virgin olive oil with fish/seafood and fermented dairy products. Beverages of choice are water, coffee, and tea. Time-restricted eating is recommended, whereby intermittent fasting is done for 12 to 16 h each day.
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•Although humans as omnivores can subsist on myriad foods, the ideal diet for health remains a dilemma.•A Pesco-Mediterranean diet of plants, nuts, EVOO, and seafood has strong cardioprotective evidence.•A daily time-restricted eating window of 8 to 12 h is a central component of this diet.•This diet is hypothetical and needs prospective and randomized studies to document its efficacy.
Dietary analysis using DNA metabarcoding is a powerful tool that is increasingly being used to further our knowledge of trophic interactions in highly complex food webs but is not without ...limitations. Omnivores, the most generalist of consumers, pose unique challenges when using such methods. Here, we provide the rationale to understand the problems associated with analysing the complex diets of omnivores. By reviewing existing metabarcoding studies of omnivorous diet, and constructing hypothetical scenarios arising from each, we outline that great caution is required when interpreting sequencing data in such cases. In essence, the problems of accidental consumption and secondary ingestion are significant sources of error when investigating omnivorous diets. The integration of multiple high throughput sequencing markers increases the taxonomic breadth of taxa detected but we reveal how some detections may be misleading. Disentangling which taxa have been deliberately or accidentally consumed by the focal omnivore is challenging and can falsely emphasise those that were not intentionally consumed, obscuring biologically meaningful interactions. Although we suggest ways to disentangle these issues, we urge that the results of such analyses should be interpreted with caution and all possible scenarios for the presence of biota within omnivores given due consideration.
Plant-based diets (PBDs) are increasingly recommended for human and planetary health. However, comprehensive evidence on the health effects of PBDs in children remains incomplete, particularly in ...vegans.
To quantify differences in body composition, cardiovascular risk, and micronutrient status of vegetarian and vegan children relative to omnivores and to estimate prevalence of abnormal micronutrient and cholesterol status in each group.
In a cross-sectional study, Polish children aged 5–10 y (63 vegetarian, 52 vegan, 72 matched omnivores) were assessed using anthropometry, deuterium dilution, DXA, and carotid ultrasound. Fasting blood samples, dietary intake, and accelerometry data were collected.
All results are reported relative to omnivores. Vegetarians had lower gluteofemoral adiposity but similar total fat and lean mass. Vegans had lower fat indices in all regions but similar lean mass. Both groups had lower bone mineral content (BMC). The difference for vegetarians attenuated after accounting for body size but remained in vegans (total body minus the head: –3.7%; 95% CI: –7.0, –0.4; lumbar spine: –5.6%; 95% CI: –10.6, –0.5). Vegetarians had lower total cholesterol, HDL, and serum B-12 and 25-hydroxyvitamin D 25(OH)D without supplementation but higher glucose, VLDL, and triglycerides. Vegans were shorter and had lower total LDL (−24 mg/dL; 95% CI: –35.2, –12.9) and HDL (−12.2 mg/dL; 95% CI: –17.3, –7.1), high-sensitivity C-reactive protein, iron status, and serum B-12 (−217.6 pmol/L; 95% CI: –305.7, –129.5) and 25(OH)D without supplementation but higher homocysteine and mean corpuscular volume. Vitamin B-12 deficiency, iron-deficiency anemia, low ferritin, and low HDL were more prevalent in vegans, who also had the lowest prevalence of high LDL. Supplementation resolved low B-12 and 25(OH)D concentrations.
Vegan diets were associated with a healthier cardiovascular risk profile but also with increased risk of nutritional deficiencies and lower BMC and height. Vegetarians showed less pronounced nutritional deficiencies but, unexpectedly, a less favorable cardiometabolic risk profile. Further research may help maximize the benefits of PBDs in children.
Biological invasions are both a pressing environmental challenge and an opportunity to investigate fundamental ecological processes, such as the role of top predators in regulating biodiversity and ...food-web structure. In whole-ecosystem manipulations of small Caribbean islands on which brown anole lizards (Anolis sagrei) were the native top predator, we experimentally staged invasions by competitors (green anoles, Anolis smaragdinus) and/or new top predators (curly-tailed lizards, Leiocephalus carinatus). We show that curly-tailed lizards destabilized the coexistence of competing prey species, contrary to the classic idea of keystone predation. Fear-driven avoidance of predators collapsed the spatial and dietary niche structure that otherwise stabilized coexistence, which intensified interspecific competition within predator-free refuges and contributed to the extinction of green-anole populations on two islands. Moreover, whereas adding either green anoles or curly-tailed lizards lengthened food chains on the islands, adding both species reversed this effect-in part because the apex predators were trophic omnivores. Our results underscore the importance of top-down control in ecological communities, but show that its outcomes depend on prey behaviour, spatial structure, and omnivory. Diversity-enhancing effects of top predators cannot be assumed, and non-consumptive effects of predation risk may be a widespread constraint on species coexistence.
Salt marshes in urban watersheds are prone to microplastics (MP) pollution due to their hydrological characteristics and exposure to urban runoff, but little is known about MP distributions in ...species from these habitats. In the current study, MP occurrence was determined in six benthic invertebrate species from salt marshes along the North Adriatic lagoons (Italy) and the Schelde estuary (Netherlands). The species represented different feeding modes and sediment localisation. 96% of the analysed specimens (330) did not contain any MP, which was consistent across different regions and sites.
Suspension and facultative deposit-feeding bivalves exhibited a lower MP occurrence (0.5–3%) relative to omnivores (95%) but contained a much more variable distribution of MP sizes, shapes and polymers. The study provides indications that MP physicochemical properties and species' ecological traits could all influence MP exposure, uptake and retention in benthic organisms inhabiting European salt marsh ecosystems.
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•Quantification of microplastics in wild benthic invertebrates from European salt marshes•Species with different ecological traits were collected.•The 96% of the analysed specimens did not contain any MP.•Omnivores contained higher quantities of microplastics than suspension and deposit feeders.•Suspension and deposit-feeders exhibited greater variability of MP typologies than omnivores.
The aim was to analyse the total food costs and the impact of food groups on total food costs among vegetarian, vegan and omnivore children and adolescents in Germany. Based on three-day weighed ...dietary records of 6–18-year-old children and adolescents of the VeChi Youth Study, the total daily food costs and food group costs (both EUR/day, EUR/1000 kcal) of a vegetarian (n = 145 records), vegan (n = 110) and omnivore (n = 135) diet were calculated. Minimum retail prices of 1000 empirically selected foods reported in the dietary records were linked to individual food intakes. The group differences were analysed using ANCOVA or Kruskal-Wallis tests. Vegans had the highest energy adjusted total food costs at 2.98 EUR/1000 kcal, vegetarians the lowest at 2.52 EUR/1000 kcal. Omnivores also had significantly higher costs than vegetarians with 2.83 EUR/1000 kcal/1000 kcal (p = 0.01), but the total costs did not differ significantly between omnivores and vegans (EUR/d and EUR/1000 kcal). Compared to vegetarians, vegans had significantly higher expenditures (EUR/day) on fruit (p = 0.0003), vegetables (p = 0.006), dairy alternatives (p = 0.0003) and legumes/nuts/seeds (p = 0.0003). Expenditure on starchy foods was significantly higher in the vegetarian or vegan than in the omnivore diet (p = 0.0003). Omnivores spent a quarter of their total food costs on animal source foods (25%), which is equivalent to the sum of food costs for legumes/nuts/seeds, dairy alternatives and meat alternatives in vegans and additionally dairy in vegetarians. The VeChi Youth Study indicated that financial constraints are not necessarily a barrier to switching to a more plant-based diet.
Stable carbon and nitrogen isotope ratios of collagen from bone and dentin have frequently been used for dietary reconstruction, but this method is limited by protein preservation. Isotopes of the ...trace element zinc (Zn) in bioapatite constitute a promising proxy to infer dietary information from extant and extinct vertebrates. The 66Zn/64Zn ratio (expressed as δ66Zn value) shows an enrichment of the heavy isotope in mammals along each trophic step. However, preservation of diet-related δ66Zn values in fossil teeth has not been assessed yet. Here, we analyzed enamel of fossil teeth from the Late Pleistocene (38.4–13.5 ka) mammalian assemblage of the Tam Hay Marklot (THM) cave in northeastern Laos, to reconstruct the food web and assess the preservation of original δ66Zn values. Distinct enamel δ66Zn values of the fossil taxa (δ66Zncarnivore < δ66Znomnivore < δ66Znherbivore) according to their expected feeding habits were observed, with a trophic carnivore-herbivore spacing of +0.60‰ and omnivores having intermediate values. Zn and trace element concentration profiles similar to those of modern teeth also indicate minimal impact of diagenesis on the enamel. While further work is needed to explore preservation for settings with different taphonomic conditions, the diet-related δ66Zn values in fossil enamel from THM cave suggest an excellent long-term preservation potential, even under tropical conditions that are well known to be adverse for collagen preservation. Zinc isotopes could thus provide a new tool to assess the diet of fossil hominins and associated fauna, as well as trophic relationships in past food webs.
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