RESUMO
OBJECTIVE: The study aimed to evaluate the dietary vitamin B6 intake and determine the vitamin B6 concentration in blood samples of German vegans. DESIGN AND SETTING: Cross-sectional study with 33 examination sites all over Germany. Subjects Ninety-three vegans (50 females) with a mean (+/- standard deviation (SD)) age of 43.7 +/- 15.7 years who took no vitamin supplements. METHODS: Dietary intake was assed using a semi-quantitative food-frequency questionnaire. Erythrocyte aspartate aminotransferase activity coefficient (EAST-AC) was calculated as the ratio of stimulated (pyridoxal 5'-phosphate added) to unstimulated activity in blood samples that were provided after an overnight fast. RESULTS: Mean +/- SD vitamin B6 intake was 2.83 +/- 0.98 mg day(-1) and mean +/- SD protein intake was 56.6 +/- 21.7 g day(-1). Of the participants 4% showed vitamin B6 intakes lower than daily recommended intakes for Germany, 16% showed EAST-AC > 1.85, and a further 58% showed EAST-AC of 1.5-1-85. Moderate vegans were affected to a lesser extent than strict vegans. None of the established confounders was a significant predictor of EAST-AC. In logistic regression analyses the contribution of nutriments and cereals to pyridoxine intake was the only predictor of EAST-AC classified as < or = 1.85 and > 1.85, respectively. CONCLUSIONS: In spite of the high total intake of vitamin B6, an adequate concentration in blood samples could not be realised for a majority of the participants. Due to the health implications of a marginal pyridoxine status, vegans should be encouraged to include foods with a high bioavailability of pyridoxine, such as beans, lentils and bananas, in the daily diet.
Assuntos
Dieta Vegetariana , Avaliação Nutricional , Estado Nutricional , Vitamina B 6/administração & dosagem , Vitamina B 6/sangue , Complexo Vitamínico B/administração & dosagem , Adulto , Aspartato Aminotransferases/metabolismo , Disponibilidade Biológica , Estudos Transversais , Eritrócitos/enzimologia , Feminino , Alemanha , Humanos , Modelos Logísticos , Masculino , Inquéritos e Questionários , Deficiência de Vitamina B 6/sangue , Deficiência de Vitamina B 6/epidemiologia , Deficiência de Vitamina B 6/prevenção & controle , Complexo Vitamínico B/sangueRESUMO
BACKGROUND/AIM: Evaluation of cardiovascular risk profile in 154 German vegans. METHODS: Cross-sectional study, Germany. Study instruments: 2 FFQ, 2 questionnaires, analyses of fasting venous blood samples. RESULTS: The total study population had a low BMI (mean: 22.3 kg/m(2)), a moderate blood pressure (mean: 120/75 mm Hg), an extremely low consumption of alcohol (mean: 0.77 g/day) and 96.8% were nonsmokers. Moderate physical activity (PAL) was reported by nearly 50%, whereas 22.7% declared to have a high PAL (>3 h/week). Median triacylglycerol (TG) was 0.81 mmol/l, total cholesterol (TC) was 4.33 mmol/l, HDL was 1.34 mmol/l. The mean TC/HDL-ratio was 3.3. Lipoprotein(a) (Lp(a)) was 8.13 mg/dl, concentrations of >30 mg/dl were prevalent in 25% of the participants. In general, status of folate and pyridoxine were sufficient, while 49.7% showed cobalamin concentrations <150 pmol/l. Plasma homocysteine levels were slightly elevated (median: 12.5 micromol/l). Cobalamin concentration and duration of vegan nutrition were the main determinants of homocysteine in the total study population. CONCLUSION: Although TC and LDL concentrations were favorable, low HDL and elevated homocysteine and Lp(a) concentrations were unfavorable. Overall, these results confirm the notion that a vegan diet is deficient in vitamin B(12), which may have an unfavorable effect on CHD risk.
Assuntos
Doenças Cardiovasculares/epidemiologia , Dieta Vegetariana , Estilo de Vida , Deficiência de Vitamina B 12/epidemiologia , Vitamina B 12/sangue , Adulto , Consumo de Bebidas Alcoólicas , Doenças Cardiovasculares/etiologia , Estudos Transversais , Ingestão de Energia , Exercício Físico/fisiologia , Feminino , Alemanha/epidemiologia , Humanos , Lipídeos/sangue , Masculino , Pessoa de Meia-Idade , Necessidades Nutricionais , Fatores de Risco , Fumar , Inquéritos e Questionários , Vitamina B 12/administração & dosagem , Deficiência de Vitamina B 12/complicaçõesRESUMO
OBJECTIVE: Evaluation of dietary intakes and lifestyle factors of German vegans. DESIGN: Cross-sectional study. SETTINGS: Germany. SUBJECTS: Subjects were recruited through journal advertisements. Of 868 volunteers, only 154 participated in all study segments (pre- and main questionnaire, two 9-day food frequency questionnaires, blood sampling) and fulfilled the following study criteria: vegan dietary intake at least 1 year prior to study start, minimum age of 18 y, no pregnancy or childbirth during the last 12 months. INTERVENTIONS: No interventions. RESULTS: All the 154 subjects had a comparatively low BMI (median 21.2 kg/m(2)), with an extremely low mean consumption of alcohol (0.77+/-3.14 g/day) and tobacco (96.8% were nonsmokers). Mean energy intake (total collective: 8.23+/-2.77 MJ) was higher in strict vegans than in moderate ones. Mean carbohydrate, fat, and protein intakes in proportion to energy (total collective: 57.1:29.7:11.6%) agreed with current recommendations. Recommended intakes for vitamins and minerals were attained through diet, except for calcium (median intake: 81.1% of recommendation), iodine (median: 40.6%), and cobalamin (median: 8.8%). For the male subgroup, the intake of a small amount of food of animal origin improved vitamin and mineral nutrient densities (except for zinc), whereas this was not the case for the female subgroup (except for calcium). CONCLUSION: In order to reach favourable vitamin and mineral intakes, vegans should consider taking supplements containing riboflavin, cobalamin, calcium, and iodine. Intake of total energy and protein should also be improved.