Annika Waldmann

Dietary intakes and lifestyle factors of a vegan population in Germany: results from the German Vegan Study

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/m2), 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.Sponsorship: EDEN Foundation, Bad Soden, Germany; Stoll VITA Foundation, Waldshut-Tiengen, Germany

Dietary Iron Intake and Iron Status of German Female Vegans: Results of the German Vegan Study

Background: As shown in previous studies vegetarians and especially vegans are at risk for iron deficiency. Our study evaluated the iron status of German female vegans. Methods: In this cross-sectional study, the dietary intakes of 75 vegan women were assessed by two 9-day food frequency questionnaires. The iron status was analyzed on the basis of blood parameters. Results: Mean daily iron intake was higher than recommended by the German Nutrition Society. Still 42% of the female vegans <50 years (young women, YW) had a daily iron intake of <18 mg/day, which is the recommended allowance by the US Food and Nutrition Board. The main dietary sources of iron were vegetables, fruits, cereals and cereal products. Median serum ferritin concentrations were 14 ng/ml for YW and 28 ng/ml for women ≧50 years (old women, OW). In all, 40% (tri-index model (TIM) 20%) of the YW and 12% (TIM 12%) of the OW were considered iron-deficient based on either serum ferritin levels of <12 ng/ml or a TIM. Only 3 women had blood parameters which are defined as iron deficiency anemia. Correlations between serum ferritin levels and dietary factors were not found. Conclusion: Although the mean iron intake was above the recommended level, 40% (TIM 20%) of the YW were considered iron-deficient. It is suggested that especially YM on a vegan diet should have their iron status monitored and should consider taking iron supplements in case of a marginal status.

Homocysteine and cobalamin status in German vegans.

OBJECTIVE The study aimed to evaluate the homocysteine and cobalamin status of German vegans and determine whether the intake of very small amounts of foods of animal origin can improve this status. DESIGN AND SETTING Cross-sectional study, Germany. SUBJECTS The dietary and nutritional intakes of 131 vegans (73 women, 58 men; age range: 20.2-82.1 years) were evaluated using a general questionnaire and two food-frequency questionnaires. RESULTS The prevalence of inadequate cobalamin status in volunteers of the German Vegan Study was 28.2%, and that of hyperhomocysteinaemia, 38.1%. Moderate vegans were affected to a lesser extent than were strict vegans. Duration of veganism and cobalamin concentration were inversely correlated (Spearmans r=-0.175, P=0.047). Folate concentration and erythrocyte aspartic acid aminotransferase activity were not correlated with plasma homocysteine concentration, but duration of veganism correlated positively with homocysteine concentration (Spearmans r=0.319, P<0.001). Cobalamin and homocysteine concentrations were inversely correlated (when controlling for duration of veganism; r=-0.602, P<0.001). CONCLUSION Cobalamin status needs to be improved in order to minimise the risk of hyperhomocysteinaemia.

German vegan study : Diet, life-style factors, and cardiovascular risk profile

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/m2), 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 µmol/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 B12, which may have an unfavorable effect on CHD risk.

Diet-Dependent Net Endogenous Acid Load of Vegan Diets in Relation to Food Groups and Bone Health-Related Nutrients: Results from the German Vegan Study

Background/Aims:Dietary composition has been shown to affect acid-base homeostasis and bone health in humans. We investigated the potential renal acid load (PRAL) and the estimated diet-dependent net acid load (net endogenous acid production, NEAP) in adult vegans and evaluated the relationships between NEAP, food groups and intake of bone health-related nutrients. Methods: The German Vegan Study (GVS) is a cross-sectional study. Data from healthy men (n = 67) and women (n = 87), aged 21–75 years, who fulfilled the study criteria (vegan diet for ≧1 year prior to study start; age ≧18 years, and no pregnancy/childbirth during the last 12 months) were included in the analysis. NEAP values were calculated from diet composition using two models: one based on the protein/potassium quotient and another taking into account an anthropometry-based loss of urinary organic anions. Results:Mean daily intakes of phosphorus, potassium, sodium, magnesium and vitamin C were above, and vitamin D and calcium below Dietary Reference Intake (DRI). Regardless of the model used, the diet in the GVS was characterized by a nearly neutral NEAP. A strong correlation was observed between the NEAP values of the two models (rs = 0.873, p < 0.001). Only the consumption of fruits decreased constantly across the increasing quartiles of NEAP. Conclusions: It can be hypothesized that vegan diets do not affect acid-base homeostasis. With respect to bone health, the significance of this finding needs further investigation.

Dietary intakes and blood concentrations of antioxidant vitamins in German vegans.

We report on an evaluation of intake and blood concentrations of antioxidant vitamins in a cross-sectional study of 104 German vegans, and examine the association between blood concentration of antioxidant vitamins and their intake as well as fruit and vegetable intake. Comparisons are made with dietary reference intakes and established threshold values (ETV) for blood concentrations. Mean intakes of vitamin C, E, and beta-carotene were higher than actual recommendations, but comparable to reported intakes in other vegan cohorts. Mean blood concentrations were 0.76 micromol/L for beta-carotene and 117 micromol/L for vitamin C, so that nearly all participants showed concentrations that were above the ETV for the prevention of chronic diseases. Although mean vitamin E intake was 24.8 mg/day, only 32% of female and 18% of male participants showed plasma concentrations above the ETV. However, the mean vitamin E/cholesterol ratio was high (5.97), indicating a good protection of low-density lipoprotein (LDL) against peroxidation. Of the reported antioxidant vitamins, only plasma vitamin C concentration was a good biomarker of fruit and vegetable intake. The high concentration of antioxidative compounds in plasma may be one of the reasons for the lower incidence of chronic diseases in people consuming a plant-only diet.

Overall Glycemic Index and Glycemic Load of Vegan Diets in Relation to Plasma Lipoproteins and Triacylglycerols

Background: To investigate the overall glycemic index (GI), glycemic load (GL), and intake of dietary fiber, and to examine the associations between these factors and plasma lipoproteins and triacylglycerols in adult vegans in the German Vegan Study (GVS). Methods: Cross-sectional study, Germany. Healthy men (n = 67) and women (n = 87), who fulfilled the study criteria (vegan diet for ≧1 year prior to study start; minimum age of 18 years; no pregnancy/childbirth during the last 12 months) and who participated in all study segments. Results: The average dietary GL of the GVS population was 144, and the average GI was 51.4. The adjusted geometric mean total, HDL, and LDL cholesterol concentrations decreased across the increasing quartiles of GL, carbohydrate and dietary fiber intake. The associations between total cholesterol, HDL cholesterol, LDL cholesterol and GL density and GI were inconsistent. Also, associations between GI, GL, the intake of carbohydrates, and triacylglycerol concentration were not observed. Conclusions: Fiber-rich vegan diets are characterized by a low GI and a low to moderate GL. The data do not support the hypothesis that a carbohydrate-rich diet per se is associated with unfavorable effects on triaclyglycerols that would be predicted to increase the risk of coronary heart disease.

Contents Vol. 59, 2011

A. Astrup, Copenhagen A. Berg, Freiburg Z.A. Bhutta, Karachi S.C. Bischoff , Stuttgart F. Branca, Rome R. Brigelius-Flohé, Nuthetal P.C. Calder, Southampton S. Carlson, Kansas City, Kan. I. Cetin, Milan R.J. Deckelbaum, New York, N.Y. T. Decsi, Pécs C.J. Field, Edmonton K. Godfrey, Southampton R. Hakkak, Little Rock, Ark. W.S. Harris, Sioux Falls, S. Dak. H. Hauner, Munich M. Hernández-Triana, Havana H. Heseker, Paderborn J. Kopecky, Prague M. Krawinkel, Giessen M. Lamprecht, Graz W. Langhans, Zurich J. Linseisen, Heidelberg O. Ljungqvist, Örebro J.A. Martinez, Pamplona H.J. McArdle, Aberdeen Y. Naito, Kyoto P.W. Nathanielsz, San Antonio, Tex. H. Oberritter, Bonn R. Saff ery, Parkville, Vic. W.H.M. Saris, Maastricht L. Serra-Majem, Las Palmas de Gran Canaria C. Sieber, Nürnberg A.P. Simopoulos, Washington, D.C. P. Singer, Petah Tikva N.W. Solomons, Guatemala City P. Stehle, Bonn I. Th orsdottir, Reykjavik K. Tontisirin, Nakhon Pathom R. Uauy, Santiago S. Villalpando, Cuernavaca Morelos T. Yoshikawa, Kyoto A. Zittermann, Bad Oeynhausen Founded 1959 as ‘Nutritio et Dieta’ by E. Azerad, H. Kapp and J. Trémolières. Continued by A. Wretlind (1961–1969). Continued by N. Zöllner (1970–1990) as ‘Nutrition and Metabolism’ (1970–1980), since 1980 integrating ‘Annales de la Nutrition et de l’Alimentation’, continued as ‘Annals of Nutrition and Metabolism’. Continued by G. Wolfram (1991–1999), Continued by I. Elmadfa (2000–2010) An Official Journal of International Union of Nutritional Sciences (IUNS) Federation of European Nutrition Societies (FENS) European Neutraceutical Association (ENA) Deutsche Gesellschaft für Ernährung (DGE)