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1.
Sci Rep ; 14(1): 4876, 2024 02 28.
Artigo em Inglês | MEDLINE | ID: mdl-38418501

RESUMO

The digitization of natural history specimens and the popularization of citizen science are creating an unprecedented availability of large amounts of biodiversity data. These biodiversity inventories can be severely affected by species misidentification, a source of taxonomic uncertainty that is rarely acknowledged in biodiversity data management. For these reasons, taxonomists debate the use of online repositories to address biological questions at the species level. Hedera L. (ivies) provides an excellent case study as it is well represented in both herbaria and online repositories with thousands of records likely to be affected by high taxonomic uncertainty. We analyze the sources and extent of taxonomic errors in the identification of the European ivy species by reviewing herbarium specimens and find a high misidentification rate (18% on average), which varies between species (maximized in H. hibernica: 55%; H. azorica: 48%; H. iberica: 36%) and regions (maximized in the UK: 38% and Spain: 27%). We find a systematic misidentification of all European ivies with H. helix behind the high misidentification rates in herbaria and warn of even higher rates in online records. We compile a spatial database to overcome the large discrepancies we observed in species distributions between online and morphologically reviewed records.


Assuntos
Hedera , Gerenciamento de Dados , Biodiversidade , Bases de Dados Factuais , Plantas
2.
Nutrients ; 16(3)2024 Feb 02.
Artigo em Inglês | MEDLINE | ID: mdl-38337732

RESUMO

Sustainable healthy diets are promoted, and consequently vegetarian diets are currently increasing. However, scientific information on their effects on bone health is scarce. A cross-sectional study was performed in adults (66% women) classified into three groups: omnivores (n = 93), lacto-ovo vegetarians (n = 96), and vegans (n = 112). Nutrient intake, body composition, physical activity, vitamin D status (25-hydroxycholecalciferol, 25-OHD), parathormone (PTH), and bone formation (bone alkaline phosphatase, BAP) and resorption (N-telopeptides of type I collagen, NTx) markers were determined. Lacto-ovo vegetarians and especially vegans showed lower protein, fat, calcium, phosphorous, vitamin D, retinol, iodine, and zinc intakes, and higher carbohydrate, fibre, carotenes, magnesium, and vitamin K intakes compared to omnivores. Body composition was similar in the three groups that performed vigorous physical activity regularly. Body bone mass and muscle mass were positively correlated with BAP, and time performing physical activity with 25-OHD. The prevalence of vitamin D deficiency or insufficiency (25-OHD < 75 nmol/L) was 93.7% in the studied population, and vitamin D deficiency (25-OHD < 25 nmol/L) was significantly higher in vegans. Vegetarians of both groups had increased PTH and NTx with vegans showing significantly higher PTH and NTx than omnivores. Conclusion: Adult vegetarians, especially vegans, should reduce the risk of bone loss by appropriate diet planning and vitamin D supplementation.


Assuntos
Veganos , Deficiência de Vitamina D , Adulto , Humanos , Feminino , Masculino , Vitamina D , Estudos Transversais , Vitaminas , Dieta Vegetariana , Dieta , Vegetarianos , Dieta Vegana , Deficiência de Vitamina D/epidemiologia , Estilo de Vida , Remodelação Óssea
3.
Nutrients ; 11(8)2019 Jul 26.
Artigo em Inglês | MEDLINE | ID: mdl-31357549

RESUMO

Vegetarian diets may compromise iron status, as they provide non-haem iron which has low bioavailability. Spanish lacto-ovo vegetarians (n = 49) and vegans (n = 55) were recruited and haematological and biochemical iron parameters were analysed. Food and supplements consumption, body composition, physical activity, menstrual blood losses and hormonal contraceptive use were assessed. Four groups were studied: Iron deficiency anaemia (IDA), iron depletion (ferritin <15 ng/mL), iron deficiency (ferritin ≥15 to ≤30 ng/mL), and iron sufficiency (ferritin >30 ng/mL). IDA was uncommon (n = 5, 4.8%), 27.9% of participants were iron-depleted, and 30.8% were iron-deficient. Serum ferritin was lower in women than men (p < 0.001) and IDA and iron depleted individuals were all women. There were no differences attributed to diet type, time being vegetarian or physical activity. The menstrual period length was negatively associated with transferrin saturation ( = -0.364, p = 0.001) and hormonal contraceptive use ( = -0.276, p = 0.014). Iron supplements were consumed most frequently by IDA and iron-deficient subjects (p = 0.031). Conclusions: Iron status did not vary between lacto-ovo vegetarians and vegans and there was not an influence of the time following a vegetarian diet. Although men were iron-sufficient, iron deficiency was frequent in women, who should apply strategies to increase iron bioavailability, especially if they experience intense menstrual blood losses.


Assuntos
Anemia Ferropriva/sangue , Dieta Vegetariana , Ferro/sangue , Estado Nutricional , Valor Nutritivo , Vegetarianos , Adulto , Anemia Ferropriva/diagnóstico , Anemia Ferropriva/epidemiologia , Anemia Ferropriva/prevenção & controle , Biomarcadores/sangue , Dieta Vegana , Dieta Vegetariana/efeitos adversos , Suplementos Nutricionais , Feminino , Ferritinas/sangue , Humanos , Ferro/administração & dosagem , Deficiências de Ferro , Masculino , Fatores de Risco , Fatores Sexuais , Espanha/epidemiologia , Transferrina/metabolismo , Veganos , Adulto Jovem
4.
Nutrients ; 11(7)2019 Jul 20.
Artigo em Inglês | MEDLINE | ID: mdl-31330792

RESUMO

Plant-based diets are becoming increasingly popular, and scientific information concerning the nutritional status in this population is needed. This study determined the fatty acid profile of Spanish lacto-ovo vegetarians (LO-vegetarians) and vegans. Participants were 104 healthy adults, LO-vegetarians (n = 49) and vegans (n = 55). Lifestyle habits and consumption of food and omega-3 supplements were estimated by questionnaires. BMI, blood pressure, and abdominal and body fat were determined. Serum was collected to analyze fatty acids, glucose, lipids, homocysteine, insulin, and leptin. Volunteers were classified according to serum omega-6 to omega-3 (n-6/n-3) ratio into three groups: n-6/n-3 < 10, n-6/n-3 ≥ 10 to 20, and n-6/n-3 > 20. Results showed low cardiovascular risk and high insulin sensitivity with negligible differences between diet types. Linoleic acid (C18:2n-6) was the major serum fatty acid, followed by oleic (C18:1n-9) and palmitic (C16:0) acids. In contrast, serum eicosapentaenoic acid (EPA, C20:5n-3) and docosahexaenoic acid (DHA, C22:6n-3) were (median, interquartile range) 0.27, 0.18% and 1.59, and 0.93%, respectively. Users of n-3 supplements (<10% of total vegetarians) had significantly higher EPA than non-users, while frequent consumption of flax-seeds was associated with increased α-linolenic acid (C18:3n-3). However, neither n-3 supplementation nor food consumption affected DHA levels in this vegetarian population.


Assuntos
Dieta Vegetariana/classificação , Ácidos Graxos Ômega-3/administração & dosagem , Vegetarianos , Adolescente , Adulto , Suplementos Nutricionais , Ácidos Graxos/sangue , Feminino , Humanos , Masculino , Espanha , Adulto Jovem
5.
Nutr Hosp ; 36(4): 950-961, 2019 Aug 26.
Artigo em Espanhol | MEDLINE | ID: mdl-31232583

RESUMO

INTRODUCTION: Vegetarian diets are booming and, although these diets have been linked to some health benefits, the low bioavailability of some micronutrients in plant foods may result in risk of nutritional deficiencies, which makes necessary adequate planning of these diets. In this regard, vitamin B12 deficiency in vegetarians has been evidenced and there is a consensus on the need of supplementation of this vitamin. Vitamin D deficiency may be more frequent than in omnivores, particularly during the winter, when skin synthesis is minimal. The low bioavailability of iron, zinc and selenium in vegetables can also affect nutritional status of vegetarians. Furthermore, vegetarian diets are usually deficient in polyunsaturated fatty acids of the omega-3 family, eicosapentaenoic (EPA) and docosahexaenoic (DHA) acids. On the other hand, these diets appear to provide adequate quantities of other vitamins, such as ascorbic acid, folic acid and the fat-soluble vitamins A and E. In this review, the characteristics of the intake of macro- and micronutrients of vegetarian diets and the diet and health relationships are presented. In addition, data on nutritional status of this population are also shown and suggestions on nutritional recommendations to prevent deficiencies are given. Finally, the possible clinical application of controlled interventions with vegetarian diets is presented.


INTRODUCCIÓN: El seguimiento de dietas vegetarianas está en auge y, aunque estas se han relacionado con algunos beneficios para la salud, la baja biodisponibilidad de determinados micronutrientes en los alimentos vegetales puede resultar en riesgo de déficit nutricional, por lo que se hace necesaria una adecuada planificación de dichas dietas. En este sentido, se ha evidenciado el déficit de vitamina B12 en vegetarianos y está consensuada la necesidad de ingerir complementos de esta vitamina. La deficiencia de vitamina D puede ser más frecuente que en omnívoros, particularmente durante el invierno, cuando la síntesis cutánea es mínima. La baja biodisponibilidad del hierro, el zinc y el selenio en los alimentos vegetales puede afectar también al estado nutricional de vegetarianos. Además, las dietas vegetarianas suelen ser deficitarias en ácidos grasos poliinsaturados de la serie omega-3, eicosapentaenoico (EPA) y docosahexaenoico (DHA). Por otro lado, estas dietas sí parecen aportar cantidades adecuadas de otras vitaminas, como el ácido ascórbico, el ácido fólico y las vitaminas liposolubles A y E. En esta revisión se presentan las características de la ingesta de macro- y micronutrientes procedentes de las dietas vegetarianas y la relación dieta-salud. Se exponen, además, datos sobre el estado nutricional de adultos que consumen dichas dietas, proponiendo recomendaciones nutricionales primordiales para prevenir deficiencias. Finalmente, se presenta la posible aplicación clínica de intervenciones controladas con dietas vegetarianas.


Assuntos
Dieta Vegetariana/efeitos adversos , Micronutrientes/farmacocinética , Vitaminas/administração & dosagem , Disponibilidade Biológica , Elementos Químicos , Humanos , Micronutrientes/administração & dosagem , Minerais/administração & dosagem , Necessidades Nutricionais , Deficiência de Vitamina B 12/etiologia , Deficiência de Vitamina D/etiologia , Vitaminas/metabolismo
6.
J Nutr Sci ; 8: e7, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30828450

RESUMO

Studies on the nutritional status of vegetarians in Spain are lacking. Prevention of vitamin B12 deficiency is the main concern, as dietary sources are of animal origin. The present study aimed to evaluate vitamin B12 and folate status of Spanish vegetarians using classical markers and functional markers. Participants were adult and healthy lacto-ovo vegetarians (forty-nine subjects) and vegans (fifty-four subjects) who underwent blood analyses and completed a FFQ. Serum vitamin B12, homocysteine (Hcy), methylmalonic acid (MMA), erythrocyte folate and haematological parameters were determined. The effects of the type of plant-based diet, and the intake of supplements and foods were studied by a FFQ. Mean erythrocyte folate was 1704 (sd 609) nmol/l. Clinical or subclinical vitamin B12 deficiency was detected in 11 % of the subjects (MMA>271 nmol/l) and 33 % of the participants showed hyperhomocysteinaemia (Hcy>15 µmol/l). Regarding plant-based diet type, significantly higher Hcy was observed in lacto-ovo vegetarians compared with vegans (P = 0·019). Moreover, use of vitamin B12 supplements involved an improvement of vitamin B12 status but further increase in erythrocyte folate (P = 0·024). Consumption of yoghurts was weakly associated with serum vitamin B12 adequacy (P = 0·049) and that of eggs with lower Hcy (P = 0·030). In conclusion, Spanish vegetarians present high folate status but vitamin B12 subclinical deficiency was demonstrated using functional markers. The lack of influence of dietary sources on functional markers and the strong effect of vitamin B12 supplement intake emphasise the need of cobalamin supplementation in both lacto-ovo vegetarians and vegans.


Assuntos
Biomarcadores/sangue , Dieta Vegana , Ácido Fólico/sangue , Estado Nutricional , Vegetarianos , Vitamina B 12/sangue , Adulto , Estudos Transversais , Dieta Vegetariana , Suplementos Nutricionais , Feminino , Homocisteína/sangue , Humanos , Hiper-Homocisteinemia/sangue , Masculino , Ácido Metilmalônico/sangue , Pessoa de Meia-Idade , Espanha , Veganos , Deficiência de Vitamina B 12/sangue , Deficiência de Vitamina B 12/diagnóstico , Deficiência de Vitamina B 12/epidemiologia , Adulto Jovem
7.
Food Funct ; 9(11): 6010-6019, 2018 Nov 14.
Artigo em Inglês | MEDLINE | ID: mdl-30382274

RESUMO

Grape polyphenols have shown a promising role in the modulation of metabolic syndrome (MetS), mostly in animal models. However, clinical studies are scarce and they usually only consider a fraction of polyphenols, ignoring the non-extractable polyphenols (high molecular weight compounds or associated with macromolecules such as dietary fibre). This study aimed at evaluating the effect of grape pomace, rich in both extractable and non-extractable polyphenols, on markers of MetS. Fifty subjects (22 women) aged 20-65 with at least two MetS factors were randomly assigned to the product (daily dose of 8 g of dried grape pomace) or to the control group in a 6 week crossover design with a 4 week wash-out. Samples were collected at the beginning and at the end of both periods; half of the participants were subjected to an oral glucose tolerance test at the beginning and the end of the supplementation period. Grape pomace supplementation significantly improved fasting insulinaemia (p < 0.01), without affecting other cardiometabolic risk parameters. A tendency towards an improvement in postprandial insulinaemia was observed, particularly in those subjects with higher fasting insulin levels. Therefore, supplementation with grape pomace may be a strategy for improving insulin sensitivity in subjects at high cardiometabolic risk.


Assuntos
Biomarcadores/sangue , Doenças Cardiovasculares/prevenção & controle , Suplementos Nutricionais , Resistência à Insulina , Síndrome Metabólica/prevenção & controle , Vitis/química , Adulto , Idoso , Glicemia/metabolismo , Colesterol/sangue , Estudos Cross-Over , Feminino , Frutas/química , Teste de Tolerância a Glucose , Humanos , Insulina/sangue , Masculino , Pessoa de Meia-Idade , Avaliação Nutricional , Preparações de Plantas/administração & dosagem , Polifenóis/administração & dosagem , Fatores de Risco , Tamanho da Amostra , Triglicerídeos/sangue , Adulto Jovem
8.
Plant Foods Hum Nutr ; 73(3): 166-171, 2018 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-29971679

RESUMO

Cobalamin deficiency represents a health issue for vegetarians, especially vegans, if supplements are not consumed. Vitamin B12 serum levels, traditionally used to assess the vitamin B12 status, can be normal under functional deficiency conditions. In this regard, methylmalonic acid (MMA) has proven to be a more specific marker to detect subclinical vitamin B12 deficiency. In this study, we present for the first time the cobalamin status of Spanish vegetarians using both vitamin B12 and MMA markers, and the effects of the plant-based diet and the intake of vitamin B12 supplements. Healthy adults were recruited (n = 103, 52% vegans). Dietary preferences and use of supplements were assessed by questionnaires and serum samples were collected and stored. Vitamin B12 was measured by chemiluminiscence and MMA by liquid chromatography tandem mass spectrometry (LC-MS/MS) using solid phase extraction for sample preparation. Obtained values, median (IQR), were: vitamin B12, 278.9 (160.2) pmol/l and MMA, 140.2 (78.9) nmol/l. No significant differences between lacto-ovo vegetarians and vegans were observed. Considering these two markers, 10% of the participants were mild vitamin B12 deficient. Supplementation (75% of the participants) was associated with higher vitamin B12 (p < 0.001) and lower MMA (p = 0.012). In conclusion, Spanish vegetarians have low risk of vitamin B12 deficiency due to vitamin B12 supplementation and the MMA determination is useful to detect mild deficiency.


Assuntos
Dieta Vegetariana/efeitos adversos , Suplementos Nutricionais , Ácido Metilmalônico/sangue , Deficiência de Vitamina B 12/dietoterapia , Vitamina B 12/farmacologia , Adulto , Biomarcadores/sangue , Cromatografia Líquida , Estudos Transversais , Dieta Vegana/efeitos adversos , Feminino , Humanos , Masculino , Espanha , Espectrometria de Massas em Tandem , Vegetarianos , Vitamina B 12/sangue , Deficiência de Vitamina B 12/sangue , Adulto Jovem
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