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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.

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.

The path followed by species in the colonization of remote oceanic islands ultimately depends on their phylogenetic constraints and ecological responses. In this study, we aim to evaluate the relative role of geographical and ecological forces in the origin and evolution of the Madeiran ivy (Hedera maderensis), a single-species endemic belonging to the western polyploid clade of Hedera. To determine the phylogenetic placement of H. maderensis within the western polyploid clade, we analyzed 40 populations (92 individuals) using genotyping-by-sequencing and including Hedera helix as outgroup. Climatic niche differences among the study species were evaluated using a database with 867 records representing the entire species ranges. To test species responses to climate, 13 vegetative and reproductive functional traits were examined for 70 populations (335 individuals). Phylogenomic results revealed a nested pattern with H. maderensis embedded within the south-western Iberian H. iberica. Gradual niche differentiation from the coldest and most continental populations of H. iberica to the warm and stable coastal population sister to H. maderensis parallels the geographical pattern observed in the phylogeny. Similarity in functional traits is observed for H. maderensis and H. iberica. The two species show leaves with higher specific leaf area (SLA), lower leaf dry matter content (LDMC) and thickness and fruits with lower pulp fraction than the other western polyploid species H. hibernica. Acquisition of a Macaronesian climatic niche and the associated functional syndrome in mainland European ivies (leaves with high SLA, and low LDMC and thickness, and fruits with less pulp content) was a key step in the colonization of Madeira by the H. iberica/H. maderensis lineage, which points to climatic pre-adaptation as key in the success of island colonization (dispersal and establishment). Once in Madeira, budding speciation was driven by geographical isolation, while ecological proc, Ministerio de Economía, Industria y Competitividad, Ministerio de Ciencia e Innovación, Comunidad de Madrid/Fondo Social Europeo, Consejo superior de Investigaciones Científicas (CSIC), Universidad Autónoma de Madrid, Depto. de Biodiversidad, Ecología y Evolución, Fac. de Ciencias Biológicas, TRUE, pub

The path followed by species in the colonization of remote oceanic islands ultimately depends on their phylogenetic constraints and ecological responses. In this study, we aim to evaluate the relative role of geographical and ecological forces in the origin and evolution of the Madeiran ivy (Hedera maderensis), a single-species endemic belonging to the western polyploid clade of Hedera. To determine the phylogenetic placement of H. maderensis within the western polyploid clade, we analyzed 40 populations (92 individuals) using genotyping-by-sequencing and including Hedera helix as outgroup. Climatic niche differences among the study species were evaluated using a database with 867 records representing the entire species ranges. To test species responses to climate, 13 vegetative and reproductive functional traits were examined for 70 populations (335 individuals). Phylogenomic results revealed a nested pattern with H. maderensis embedded within the south-western Iberian H. iberica. Gradual niche differentiation from the coldest and most continental populations of H. iberica to the warm and stable coastal population sister to H. maderensis parallels the geographical pattern observed in the phylogeny. Similarity in functional traits is observed for H. maderensis and H. iberica. The two species show leaves with higher specific leaf area (SLA), lower leaf dry matter content (LDMC) and thickness and fruits with lower pulp fraction than the other western polyploid species H. hibernica. Acquisition of a Macaronesian climatic niche and the associated functional syndrome in mainland European ivies (leaves with high SLA, and low LDMC and thickness, and fruits with less pulp content) was a key step in the colonization of Madeira by the H. iberica/H. maderensis lineage, which points to climatic pre-adaptation as key in the success of island colonization (dispersal and establishment). Once in Madeira, budding speciation was driven by geographical isolation, while ecological proc

[Background]: Controversy exists on the relationship between iron metabolism and cardiometabolic risk. The aim of this study was to determine if there is a link between dysmetabolic iron and cardiometabolic markers in subjects with excess body weight, [Methods]: Cross-sectional study with fifty participants presenting overweight or obesity and at least another metabolic syndrome factor. Determinations: anthropometry, body composition, blood pressure, lipids, glucose, insulin, leptin, areas under the curve (AUC) for glucose and insulin after an oral glucose tolerance test, hs-C reactive protein (hs-CRP), blood count, ferritin, transferrin, transferrin saturation (TSAT), soluble transferrin receptor (sTfR). Gender-adjusted linear correlations and two independent samples t tests were used., [Results]: Ferritin was positively correlated with insulin-AUC (r = 0.547, p = 0.008) and TSAT was negatively correlated with waist-hip ratio (r = −0.385, p = 0.008), insulin (r = −0.551, p < 0.001), and insulin resistance (HOMA-IR, r = −0.586, p < 0.001). Subjects with TSAT ≤ 20% had higher insulin (p = 0.012) and HOMA-IR (p = 0.003) compared to those with TSAT > 20%. In conclusion, the observed results suggest that iron transport and storage are altered in subjects with overweight/obesity, at the same time that they exhibit the characteristic features of insulin resistance. Nevertheless, this occurs without iron overload or deficiency. These results should be validated in wider cohorts since they suggest that iron transport and storage should be assessed when performing the clinical evaluation of subjects with excess body weight.

Although the prevalence of anaemia was low and men had a sufficient iron status, vegetarian women presented low iron stores, with iron deficiency or depletion. The absence of differences between lacto-ovo vegetarians and vegans suggests that the type of vegetarian diet does not have an influence on iron status. We recommend that vegetarian women combine foods properly in order to increase bioavailability and prevent iron deficiency.

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.

[ES]: 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., [EN]: 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.

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.

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.

[Introduction]: Vitamin B12 deficiency is a common health issue in vegetarians, and especially in vegans, if fortified foods or supplements are not consumed. There is no ideal diagnostic marker of vitamin B12 deficiency, as the single determination of the total serum vitamin levels usually does not rule out functional deficiency conditions. Methylmalonic acid (MMA), an intermediate of the one carbon metabolism in which vitamin B12 participates as a cofactor, increases prior to the vitamin B12 decrease and is a good biomarker of the status of this vitamin. [Objectives]: In this study we present for the first time the vitamin B12 status of Spanish vegetarians, studied by both serum MMA and vitamin B12. In addition, we examine the influence of the dietary preferences (ovo-lacto vegetarian or vegan) and the intake of cobalamin supplements. [Methods]: Healthy vegetarian adults (n=104) were recruited. Dietary patterns and consumption of supplements were assessed by questionnaires and blood samples were collected. Serum vitamin B12 was measured by chemiluminiscence and serum MMA by liquid chromatography tandem mass spectrometry (LC-MS/MS). [Results]: Obtained median (IQR) values were: vitamin B12, 280.4 (160.2) pmol/l, MMA, 139.9 (78.9) nmol/l. There were no differences associated to gender, age or the type of vegetarian diet. The consideration of vitamin B12 levels alone resulted in the detection of 2 deficient individuals, while the addition of MMA as a second marker identified 10% of mild deficient subjects. Consumption of vitamin B12 supplements, by 75% of the participants, involved higher vitamin B12 (p<0.001) and lower MMA (p=0.012) levels compared to non-consumption. [Conclusions]: The studied Spanish lacto-ovo vegetarians and vegans presented a generally sufficient cobalamin status, which can be explained by the extended awareness of the need of supplement consumption.

En la actualidad, el seguimiento de dietas basadas en alimentos vegetales ha aumentado considerablemente. Aunque existen múltiples variantes de estas dietas, las más comunes son la dieta ovolactovegetariana, que puede incluir huevos, lácteos y miel, y la vegetariana estricta o vegana, que no incluye ningún alimento de origen animal ni derivados. Los conocimientos sobre el estado nutricional en esta población son muy escasos y es preciso realizar estudios clínicos con la metodología científica adecuada reproducible y contrastable. A priori, la ingesta de los ácidos grasos de la serie omega-3 eicosapentaenoico (EPA) y docosahexaenoico (DHA), cuyas principales fuentes dietéticas son el pescado y el marisco, puede ser insuficiente en población vegetariana. En relación a los micronutrientes, esta población puede sufrir deficiencias de vitamina B12, que sólo se encuentra en alimentos de origen animal, y de vitamina D, particularmente durante el invierno cuando la síntesis cutánea es mínima. Por otro lado, otras vitaminas, como el ácido ascórbico o el ácido fólico, tendrían un suficiente aporte procedente de los alimentos vegetales; y las vitaminas liposolubles A y E, podrían estar cubiertas gracias al consumo de semillas, frutos secos y aceite. El estado de hierro en esta población también es un tema de interés, ya que el hierro de los alimentos vegetales tiene menor biodisponibilidad que el de los alimentos de origen animal. Uno de los objetivos actuales del grupo de investigación es estudiar los hábitos alimentarios y estilo de vida de vegetarianos y veganos españoles. Se analizarán conductas relacionadas con la salud distintas a la dieta como el consumo de complementos nutricionales, la actividad física o los métodos utilizados para cocinar los alimentos, entre otros. Dicho estudio permitirá diseñar los alimentos y productos más adecuados para este colectivo, y realizar intervenciones adecuadas y recomendaciones personalizadas para mantener su estado de salud.

[Rationale]: Methylmalonic acid (MMA), an intermediate of the vitamin B12 pathway, is an early indicator of cobalamin deficiency. In this study, for the first time we determined MMA in Spanish vegetarians to detect vitamin B12 deficiency. [Methods]: Healthy adult lacto-ovo vegetarians and vegans were recruited (n=104). Intake of vitamin B12 supplements was assessed by a questionnaire. Serum vitamin B12 levels were measured by chemiluminiscence and serum MMA by an optimized liquid chromatography tandem mass spectrometry (LC-MS/MS) method preceded by solid phase extraction. Accuracy of the used calibrators and intra-assay and inter-assay variability of the quality controls were calculated to provide reliability to the obtained results. Differences in vitamin B12 and MMA levels regarding supplementation were assessed by ANOVA tests. [Results]: The accuracy of the calibrators was 86e106%, and quality controls were within the expected range for every reading. The intra-assay and inter-assay coefficients of variation were always below a 10%. While vitamin B12 levels were under the cut-off for deficiency in only two subjects, MMA was high in eleven individuals. Furthermore, vegetarians consuming cobalamin supplements presented higher vitamin B12 (p<0.001) and lower MMA (p=0.012) levels. [Conclusions]: The LC-MS/MS method for MMA measurement proved its applicability to detect subclinical vitamin B12 deficiency. The status of vitamin B12, linked to supplementation, was generally adequate in the studied population, which emphasizes the need for supplementation to maintain suitable levels of this vitamin in vegetarians.

[Introduction]: Plant food-based diets have become progressively common in developed countries, including Spain. However, information on the nutritional status of vegetarians according to biochemical determinations is lacking. [Objectives]: The aim of this study was to characterise the fatty acid profile of a Spanish vegetarian population. [Methods]: The design was a cross-sectional observational pilot study. Healthy adult vegetarians were recruited in the Madrid region (n=104, 83 women, 21 men). According to the type of diet, 49 were ovo-lacto vegetarians (11 men and 38 women) and 55 vegans (12 men and 43 women). Food intake and the use of supplements were assessed by a food frequency questionnaire and blood samples were collected and stored. Serum fatty acids were analysed by gas chromatography. [Results]: Fatty acid profiles did not vary significantly between vegetarians and vegans, or in relation to gender. Percentages of fatty acids of the whole studied population were 27.5% saturated (SFA), 24.6% monounsaturated (MUFA), and 47.9% polyunsaturated (PUFA) of which 45.2% were omega-6 (n-6) and 2.7% omega-3 (n-3). The main serum fatty acids were linoleic acid (34.4 ± 4.4%), oleic acid (23.4 ± 5.6%), palmitic acid (19.2 ± 2.3%), and arachidonic acid (8.3 ± 1.8%). A high PUFA n-6/n-3 ratio (19:1) was found in this population. Consumers of n-3 supplements (n=9, 10% of the population) compared to non-consumers presented a significantly lower serum n-6/n-3 ratio, 14:1 compared to 19:1 (p=0.025), due to significantly higher serum n-3 levels (3.7% compared to 2.6%, p=0.003) and a tendency to lower n-6 levels (42.6 % compared to 45.5%). [Conclusions]: Vegetarians whose diets are n-3-supplemented presented a more adequate serum lipid profile with higher PUFA n-3 levels and n-6/n-3 ratio.

[Rationale]: Excess body iron has been related with oxidative stress, and several components of the metabolic syndrome (MetS). Here we present the relationship between serum ferritin levels -subrogate marker of body iron- and serum lipids, abdominal adiposity, insulin resistance and leptin levels. [Methods]: The design was a cross-sectional observational pilot study. Fifty subjects (aged 18-65; 55% men) with at least two MetS risk factors (according to WHO criteria) were recruited in the Madrid region. Blood pressure, BMI, and waist-to-hip ratio (WHR) were determined. Biochemical determinations were: serum ferritin, serum transferrin, transferrin saturation, soluble transferrin receptor (sTfR), fasting glucose, insulin, lipids, C-reactive protein, and leptin. An oral glucose tolerance test was also performed and postprandial insulin and glucose levels were measured and the areas under the curve calculated for the period 0¿120 min (AUC). The homeostasis model assessment index (HOMA-IR) and homeostasis model assessment index-beta (HOMA-B) were calculated. Data were analyzed by categorical principal components analysis (CATPCA) and stepwise multiple linear regression models. [Results]: Serum ferritin was significantly related with WRH (r=0.485, p=0.001) and marginally with triglycerides. In the best regression model, predictors of ferritin were insulin postprandial AUC, HOMA-B, and leptin (r=0.859, p<0.001). [Conclusions]: New significant associations between serum ferritin and markers of insulin resistance were found in a population (n=50) at high cardiometabolic risk. These results should be confirmed in a wider population, in order to contribute to the elucidation of the role of iron in cardiometabolic pathologies.