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1.
Nutrients ; 16(9)2024 Apr 29.
Artigo em Inglês | MEDLINE | ID: mdl-38732591

RESUMO

BACKGROUND: Plant-based diets are not inherently healthy. Similar to omnivorous diets, they may contain excessive amounts of sugar, sodium, and saturated fats, or lack diversity. Moreover, vegans might be at risk of inadequate intake of certain vitamins and minerals commonly found in foods that they avoid. We developed the VEGANScreener, a tool designed to assess the diet quality of vegans in Europe. METHODS: Our approach combined best practices in developing diet quality metrics with scale development approaches and involved the following: (a) narrative literature synthesis, (b) evidence evaluation by an international panel of experts, and (c) translation of evidence into a diet screener. We employed a modified Delphi technique to gather opinions from an international expert panel. RESULTS: Twenty-five experts in the fields of nutrition, epidemiology, preventive medicine, and diet assessment participated in the first round, and nineteen participated in the subsequent round. Initially, these experts provided feedback on a pool of 38 proposed items from the literature review. Consequently, 35 revised items, with 17 having multiple versions, were suggested for further consideration. In the second round, 29 items were retained, and any residual issues were addressed in the final consensus meeting. The ultimate screener draft encompassed 29 questions, with 17 focusing on foods and nutrients to promote, and 12 addressing foods and nutrients to limit. The screener contained 24 food-based and 5 nutrient-based questions. CONCLUSIONS: We elucidated the development process of the VEGANScreener, a novel diet quality screener for vegans. Future endeavors involve contrasting the VEGANScreener against benchmark diet assessment methodologies and nutritional biomarkers and testing its acceptance. Once validated, this instrument holds potential for deployment as a self-assessment application for vegans and as a preliminary dietary screening and counseling tool in healthcare settings.


Assuntos
Dieta Vegana , Humanos , Europa (Continente) , Técnica Delphi , Avaliação Nutricional
2.
Crit Rev Food Sci Nutr ; 63(29): 9926-9936, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37962057

RESUMO

To summarize and evaluate the evidence on the health impact of a vegan diet, we conducted an umbrella review of systematic reviews and meta-analyses. PubMed, Cochrane Library, Web of Science and Epistemonikos were searched up to September 2021. Meta-analyses were recalculated by using a random effects model. The certainty of evidence (CoE) was evaluated by the GRADE approach. For the general healthy population, a vegan diet was effective for reducing body weight [MD (95% CI): -2.52 kg (-3.06, -1.98), n = 8 RCTs; moderate CoE] and was associated with further health benefits (with low CoE), including a lower risk of cancer incidence [SRR (95% CI): 0.84 (0.75, 0.95), n = 2] and a trend for lower risk of all-cause mortality [SRR (95% CI): 0.87 (0.75, 1.01), n = 2], as well as lower ApoB levels [MD (95% CI): -0.19 µmol/L (-0.23, -0.15), n = 7 RCTs). The findings suggested adverse associations for a vegan diet with risk of fractures [SRR (95% CI): 1.46 (1.03, 2.07), n = 3; low CoE]. For persons with diabetes or at high CVD risk, a vegan diet reduced measures of adiposity, total cholesterol, LDL and improved glycemic control (CoE moderate to low). A vegan diet may have the potential for the prevention of cardiometabolic health, but it may also impair bone health. More well-conducted primary studies are warranted.


Assuntos
Dieta Vegana , Neoplasias , Humanos , Revisões Sistemáticas como Assunto , Peso Corporal , Neoplasias/prevenção & controle , Medição de Risco
3.
Food Nutr Res ; 672023.
Artigo em Inglês | MEDLINE | ID: mdl-37808206

RESUMO

Despite development in cancer treatment and prevention options during the past few years, cancer of the pancreas remains a diagnosis associated with poor prognosis and limited options for prevention. Diet has proven to be an important risk factor for development of many types of cancer, particularly for cancers of the digestive system. Still, evidence regarding its relation to pancreatic cancer remains ambiguous. To investigate the relationship between diet and pancreatic cancer, an analysis of dietary patterns in participants from the Norwegian Women and Cancer Study (n = 89,156; 305 pancreatic cancer cases) was performed. Cox regression analysis was used for studying possible associations between dietary patterns, derived from principal component analysis, and pancreatic cancer incidence. The four most prominent dietary patterns were identified and described: European pattern, animal food consumers' dietary pattern, traditional Norwegian pattern, and alcohol-abstaining dietary pattern. In analysis without adjustment for confounders, being in the highest tertile of the abstaining dietary pattern was associated with lower risk of pancreatic cancer in comparison to the lowest tertile (hazard ratios [HR]: 0.66, 95% confidence interval [CI]: 0.49-0.89). After additional adjustment for height and smoking status, no dietary pattern was associated with increased pancreatic cancer risk, nor was there any difference in effect estimates between strata of smokers and non-smokers. The results of our current analysis do not support the role of major dietary patterns in the development of pancreatic cancer.

4.
Crit Rev Food Sci Nutr ; : 1-12, 2023 Oct 09.
Artigo em Inglês | MEDLINE | ID: mdl-37811643

RESUMO

Health effects of vegan diets among children and adolescents are a controversial public health topic. Thus, the aim of the present systematic review is to evaluate a broad range of health outcomes among vegan children and adolescents aged 0 to 18 years. 18 studies met the inclusion criteria (17 cross-sectional, 1 RCT). Meta-analyses showed lower protein, calcium, vitamin B2, saturated fatty acid, and cholesterol intakes, and lower ferritin, HDL and LDL levels as well as height in vegan compared to omnivorous children/adolescents. Higher intakes of carbohydrates, polyunsaturated fatty acids, fiber, folate, vitamins C and E, magnesium, iron, and potassium were observed in vegans. Blood levels of vitamin B12 were higher among vegan children due to supplement use. Single study results suggested further differences between vegan and non-vegan children, such as lower bone mineral content or urinary iodine among vegan children. Risk of Bias was rated as high or very high in 7 out of 18 studies. The certainty of evidence for the meta-analyses was low (n = 2) or very low (n = 46). Overall, the available evidence points to both risks and benefits associated with a vegan diet among children, although more and better designed studies are needed.

5.
Eur J Clin Nutr ; 77(11): 1061-1070, 2023 11.
Artigo em Inglês | MEDLINE | ID: mdl-37488261

RESUMO

BACKGROUND: The intake and homeostasis of iodine, an essential micronutrient that plays a vital role in thyroid physiology, is of particular concern with the increasing popularity of vegetarian (VG) and vegan (VN) diets. Children on these restrictive diets may be at risk of possible adverse effects on growth and development, but there is currently a lack of recent epidemiological studies on this topic. METHODS: We gathered clinical, anthropometric, and blood/urine data on iodine status and thyroid function from children aged 0-18 years who followed either a VG diet (n = 91), VN diet (n = 75), or omnivore diet (OM, n = 52). Cross-sectional comparison of the groups and linear regression was used. Stratified analyses were performed based on age (according to WHO): 0-5 years and 6-18 years. RESULTS: Our study revealed no significant differences in levels of thyroid-stimulating hormone (TSH), triiodothyronine (fT3), thyroglobulin (TG) or anti-thyroid peroxidase antibody (ATPOc) between the VG, VN, and OM groups. However, thyroxine (fT4) levels were found to be higher in the VN group compared to the OM group (15.00 ± 1.73 vs. 16.17 ± 1.82 pmol/l, p < 0.001). The presence of anti-thyroglobulin antibodies (AhTGc) was notably more common in the VG (18.2%)/VN (35.0%) groups than in the OM group (2.1%) (p < 0.001). Regarding iodine status, the concentration of iodine in spot urine (UIC) was found to be highest in the OM group (197.28 ± 105.35 vs. VG: 177.95 ± 155.88 vs. VN: 162.97 ± 164.51 µg/l, p < 0.001). Notably, the lowest (5.99 µg/l) and highest (991.80 µg/l) levels were measured in the VN group. Of the participants, 31 VN, 31 VG and 10 OM children met the criteria for iodine deficiency (i.e., UIC < 100 µg/l). We found that children with regular iodine supplementation had higher UIC (p < 0.001). Importantly, the median UIC was above 100 µg/l in all three groups, through the recommended intake (RDI) of iodine was rarely met throughout the groups. CONCLUSION: We have observed a trend to lower UIC values in VN as compared to OM. This trend is also reflected in the median UIC values, even though the median UIC values were above the WHO cut-off (e.g., 100 µg/l) for iodine deficiency in all dietary groups. These results suggest that VN and VG children may be more at higher risk of iodine deficiency, this theory is also supported by higher prevalence of AhTGc positivity. Further research is needed to investigate the long-term impact of these dietary patterns on iodine status and thyroid function in children. Given our findings, it may also be necessary to consider new guidelines for supplementing children following VG and VN diets to ensure their iodine needs are met.


Assuntos
Iodo , Veganos , Humanos , Criança , Estudos Transversais , Prevalência , República Tcheca , Tireotropina , Vegetarianos
6.
Rocz Panstw Zakl Hig ; 74(2): 195-205, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37309911

RESUMO

Background: The number of vegans in the world is growing and in Slovakia and the Czech Republic they make up 1% of the population. Vegan diet excludes all foods of animal origin and vegans who do not use vitamin B12 supplements are at risk of the vitamin B12 deficiency. Objective: The aim of this study was to determine what proportion of Czech and Slovak vegans use vitamin B12 supplements regularly, irregularly or not at all and what is their supplemental cobalamin intake. Materials and methods: The research involved 1337 self-identified vegans from Slovakia and the Czech Republic who were interviewed using the CAWI (Computer-Assisted Web Interview) method. Participants were recruited by posts in veganism-themed social media groups. Results: Out of 1337 vegans 55.5% supplemented cobalamin regularly, 32.54% irregularly and 11.97% were not supplementing. Rate of not supplementing individuals was 5.04% higher in Slovaks than in Czechs. Short-term vegans had a significantly higher rate of not supplementing individuals (17.99%) compared to medium-term (8.37%) and long-term vegans (7.50%). Mean weekly cobalamin intake from supplements was 2938.34±2566.60 µg in regularly supplementing vegans compared to 1630.31±1949.27 µg in irregularly supplementing vegans, particularly due to the lower weekly supplementation frequency among irregularly (2.93) compared to regularly supplementing vegans (5.27). Conclusions: The rate of supplementation in Slovak and particularly Czech vegans was higher than in other countries. The number of not supplementing individuals was significantly higher among short-term vegans, indicating that there is still a need for education on the importance of adequate and regular cobalamin supplementation, especially in new vegans. Our results support the hypothesis that the reason for higher rate of cobalamin deficiency in irregularly compared to regularly supplementing vegans is the lower cobalamin intake caused by lower supplementation frequency.


Assuntos
Dieta Vegana , Veganos , Animais , Humanos , Estudos Transversais , Eslováquia , Vitamina B 12 , República Tcheca , Suplementos Nutricionais
7.
BMC Med ; 20(1): 461, 2022 11 25.
Artigo em Inglês | MEDLINE | ID: mdl-36434597

RESUMO

BACKGROUND: Observational studies made it possible to assess the impact of risk factors on the long-term effectiveness of mRNA and adenoviral vector (AdV) vaccines against COVID-19. METHODS: A computerized literature search was undertaken using the MEDLINE, EMBASE, and MedRxiv databases to identify eligible studies, with no language restrictions, published up to 28 February 2022. Eligible were observational studies assessing vaccine effectiveness (VE) by disease severity with reference groups of unvaccinated participants or participants immunized with one, two, or three vaccine doses. Our study was carried out in compliance with the PRISMA and MOOSE guidelines. The risk of study bias was identified using the Newcastle-Ottawa Quality Assessment Scale. The GRADE guidelines were applied to assess the strength of evidence for the primary outcome. The synthesis was conducted using a meta-analysis and meta-regression. RESULTS: Out of a total of 14,155 publications, 290 studies were included. Early VE of full vaccination against COVID-19 of any symptomatology and severity decreased from 96% (95% CI, 95-96%) for mRNA and from 86% (95% CI, 83-89%) for AdV vaccines to 67% for both vaccine types in the last 2 months of 2021. A similar 1-year decline from 98 to 86% was found for severe COVID-19 after full immunization with mRNA, but not with AdV vaccines providing persistent 82-87% effectiveness. Variant-reduced VE was only associated with Omicron regardless of disease severity, vaccine type, or vaccination completeness. The level of protection was reduced in participants aged >65 years, with a comorbidity or those in long-term care or residential homes independently of the number of doses received. The booster effect of the third mRNA dose was unclear because incompletely restored effectiveness, regardless of disease severity, declined within a short-term interval of 4 months. CONCLUSIONS: Full vaccination provided an early high, yet waning level of protection against COVID-19 of any severity with a strong impact on the high-risk population. Moreover, the potential risk of new antigenically distinct variants should not be underestimated, and any future immunization strategy should include variant-updated vaccines.


Assuntos
Vacinas contra COVID-19 , COVID-19 , Humanos , COVID-19/prevenção & controle , Eficácia de Vacinas , Fatores de Risco , RNA Mensageiro
8.
Nutrients ; 14(3)2022 Jan 26.
Artigo em Inglês | MEDLINE | ID: mdl-35276893

RESUMO

Vegetarian (VG) and vegan (VN) diets in childhood are of growing interest due to their perceived health and environmental benefits. Concerns remain due to the possible disruption of healthy growth and development of children because of the scarcity of evidence-based studies. Among the nutrients of special concern is vitamin B12. Therefore, the Czech Vegan Children Study (CAROTS) decided to examine the relationship between B12 metabolism parameters and B12 intake through diet and supplementation. We analyzed laboratory parameters within n = 79 VG, n = 69 VN, and n = 52 omnivores (OM) children (0−18 years old). There were no significant differences in levels of holotranscobalamin (aB12), folate, homocysteine (hcys), or mean corpuscular volume. However, there was a significant difference in levels of cyanocobalamin (B12) (p = 0.018), even though we identified only n = 1 VG and n = 2 VN children as B12 deficient. On the other hand, we identified n = 35 VG, n = 28 VN, and n = 9 OM children with vitamin B12 hypervitaminosis (p = 0.004). This finding was related to a high prevalence of over-supplementation in the group (mean dose for VG 178.19 ± 238.5 µg per day; VN 278.35 ± 394.63 µg per day). Additionally, we found a significant (p < 0.05) difference between B12, aB12, and hcys levels of supplemented vs. non-supplemented VG/VN children. This can show that the intake of vitamin B12 via diet in the VG group might not be sufficient. Secondly, we analyzed a relation between supplement use in pregnancy and breastfeeding and its impact on vitamin B12 levels of children aged 0−3 years. Out of n = 46 mothers, only n = 3 (e.g., 6.5%) were not supplemented at all. We have not identified any clinical manifestation of B12 deficiency and only n = 1 child with low serum cobalamin, a child who did not receive vitamin B12 supplementation and whose mother took only low doses of vitamin B12 (25/µg/day).To conclude, we did not observe any life-threatening or severe consequences of laboratory-stated vitamin B12 deficiency; thus, our group was well supplemented. On the other hand, we have identified many subjects with vitamin B12 hypervitaminosis of unknown impact on their health. Further research and new guidelines for B12 supplementation among VG and VN children are needed.


Assuntos
Deficiência de Vitamina B 12 , Vitamina B 12 , Adolescente , Criança , Pré-Escolar , Estudos Transversais , República Tcheca/epidemiologia , Suplementos Nutricionais , Feminino , Hábitos , Humanos , Lactente , Recém-Nascido , Gravidez , Prevalência , Veganos , Vegetarianos , Deficiência de Vitamina B 12/epidemiologia
9.
Cas Lek Cesk ; 160(6): 249-254, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34915716

RESUMO

Iodine deficiency can cause several serious disorders, which are referred to as iodine deficiency disorders. Consequences of iodine deficiency can be prevented, for example by increased dietary intake of iodine. In the diet, iodine is found mainly in sea fish, seafood and seaweed (kelp, kombu, nori, wakame), eggs and dairy products, but also in mineral waters. An important source of iodine is also table salt, which has been fortified in the Czech Republic, resp. Czechoslovakia since 1947; currently valid concentration 27±7 mg/kg dates from 1997. Iodine deficiency can be prevented or solved with the help of increasingly popular food supplements. To describe the range of supplements available on the Czech market, online investigation of retailers was carried out in the period from February to the end of March 2021. Approximately 91 different food supplements were found to have listed, which have iodine in their composition. These accessories are available in various forms. The price for the recommended daily dose ranges from 1 to about 30 CZK, exceptionally raises even to 60 CZK. Supplements were divided into 8 groups according to different specifications and suitability for use for certain groups in the population. The spectrum of available food supplements is rich and in their choice care should be taken in consulting doctor or pharmacist, as the content of the supplement may exceed a safe dose for long-term use.


Assuntos
Iodo , República Tcheca , Suplementos Nutricionais , Humanos
10.
Front Nutr ; 8: 783302, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-35071294

RESUMO

Background and Aim: Plant-based diets are associated with potential health benefits, but the contribution of gut microbiota remains to be clarified. We aimed to identify differences in key features of microbiome composition and function with relevance to metabolic health in individuals adhering to a vegan vs. omnivore diet. Methods: This cross-sectional study involved lean, healthy vegans (n = 62) and omnivore (n = 33) subjects. We assessed their glucose and lipid metabolism and employed an integrated multi-omics approach (16S rRNA sequencing, metabolomics profiling) to compare dietary intake, metabolic health, gut microbiome, and fecal, serum, and urine metabolomes. Results: The vegans had more favorable glucose and lipid homeostasis profiles than the omnivores. Long-term reported adherence to a vegan diet affected only 14.8% of all detected bacterial genera in fecal microbiome. However, significant differences in vegan and omnivore metabolomes were observed. In feces, 43.3% of all identified metabolites were significantly different between the vegans and omnivores, such as amino acid fermentation products p-cresol, scatole, indole, methional (lower in the vegans), and polysaccharide fermentation product short- and medium-chain fatty acids (SCFAs, MCFAs), and their derivatives (higher in the vegans). Vegan serum metabolome differed markedly from the omnivores (55.8% of all metabolites), especially in amino acid composition, such as low BCAAs, high SCFAs (formic-, acetic-, propionic-, butyric acids), and dimethylsulfone, the latter two being potential host microbiome co-metabolites. Using a machine-learning approach, we tested the discriminative power of each dataset. Best results were obtained for serum metabolome (accuracy rate 91.6%). Conclusion: While only small differences in the gut microbiota were found between the groups, their metabolic activity differed substantially. In particular, we observed a significantly different abundance of fermentation products associated with protein and carbohydrate intakes in the vegans. Vegans had significantly lower abundances of potentially harmful (such as p-cresol, lithocholic acid, BCAAs, aromatic compounds, etc.) and higher occurrence of potentially beneficial metabolites (SCFAs and their derivatives).

11.
J Nutr ; 150(5): 1266-1271, 2020 05 01.
Artigo em Inglês | MEDLINE | ID: mdl-32055831

RESUMO

BACKGROUND: Persons following plant-based diets have lower bone mineral density (BMD) and higher fracture risk, possibly due to suboptimal nutrient supply. However, anthropometric measures were not considered as potential confounders in many previous studies, and body mass index (BMI) is positively associated with BMD but also generally lower among vegans and vegetarians. OBJECTIVES: Our objective was to investigate if BMD measurements differ between vegetarians and nonvegetarians from the adult general population when accounting for important determinants of BMD, especially BMI and waist circumference. METHODS: Using data from the NHANES (cycles 2007-2008 and 2009-2010), we evaluated the differences in BMD (femoral neck, total femoral, and total lumbar spine) between adult vegetarians and nonvegetarians. Linear regression models were used to determine the associations between BMD and diet. Statistical models were adjusted for important factors, i.e., age, sex, race/ethnicity, smoking status, alcohol consumption, serum vitamin D and calcium concentrations, waist circumference, and BMI. RESULTS: In statistical models adjusted for age, sex, race/ethnicity, menopausal status, and education level, BMD values were significantly lower among vegetarians than among nonvegetarians (P < 0.001). These differences were attenuated upon adjustment for lifestyle factors, and became statistically nonsignificant upon adjustment for anthropometric variables (BMI and waist circumference) for femoral neck (0.77 compared with 0.79 g/cm2 among vegetarians versus nonvegetarians, P = 0.10) and total femoral BMD (0.88 compared with 0.90 g/cm2, P = 0.12). A small but statistically significant difference remained for total lumbar spine BMD (1.01 compared with 1.04 g/cm2, P = 0.005). CONCLUSIONS: These findings suggest that lower BMD among adult vegetarians is in larger parts explained by lower BMI and waist circumference.


Assuntos
Índice de Massa Corporal , Densidade Óssea , Dieta , Vegetarianos , Circunferência da Cintura , Adulto , Antropometria , Feminino , Colo do Fêmur , Humanos , Estilo de Vida , Vértebras Lombares , Masculino , Pessoa de Meia-Idade , Inquéritos Nutricionais , Veganos
12.
Nutrients ; 11(12)2019 Dec 10.
Artigo em Inglês | MEDLINE | ID: mdl-31835560

RESUMO

As not much is known about the prevalence and predictors of nutritional deficiencies among vegans in the Czech Republic, we evaluated whether supplement use and duration of adherence to the vegan diet are associated with the risk of cobalamin and iron deficiencies. Associations between self-reported supplementation and duration of vegan diet with biomarkers of cobalamin (serum cobalamin, holotranscobalamin, homocysteine, folate) and iron status (serum ferritin, iron binding capacity, transferrin and saturation of transferrin) were assessed by cross-sectional analyses of medical data from a clinical nutrition center. Data from 151 (72 females) adult vegans (age 18-67 years), who were free of major chronic diseases and 85 (40 females) healthy non-vegans (age 21-47 years) were analyzed. Overall, vegans had significantly lower cobalamin, hemoglobin and ferritin levels, but higher folate and MCV values compared to non-vegans. Vegans not using cobalamin supplements were at higher risk of low plasma cobalamin than regularly supplementing vegans (OR: 4.41, 95% CI 1.2-16.16 for cobalamin, OR: 19.18, 95% CI 1.02-359.42 for holotranscobalamin), whereas no significant differences in cobalamin status related to duration of the vegan diet were observed. Regularly supplementing vegans had similar levels of cobalamin/holotranscobalamin as non-vegans. Despite lower ferritin and hemoglobin levels, there was no indication of a higher risk of iron-deficiency among vegans. To conclude cobalamin deficiency risk depends on supplementation status and not on the duration of an exclusive vegan diet, which underlines the need to integrate cobalamin status monitoring and counselling on supplement use in routine clinical care in the Czech Republic.


Assuntos
Anemia Ferropriva/epidemiologia , Dieta Vegana , Suplementos Nutricionais , Deficiência de Vitamina B 12/epidemiologia , Vitamina B 12/administração & dosagem , Adolescente , Adulto , Idoso , Anemia Ferropriva/sangue , Estudos Transversais , República Tcheca/epidemiologia , Feminino , Ferritinas/sangue , Ácido Fólico/sangue , Humanos , Masculino , Pessoa de Meia-Idade , Estado Nutricional , Prevalência , Veganos , Vitamina B 12/sangue , Deficiência de Vitamina B 12/sangue , Adulto Jovem
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