The taurine content of common foodstuffs

There is growing evidence that taurine is a biologically valuable nutrient. However, there are few published data concerning the taurine content of different foods. We measured the taurine content of 29 meats, including both cooked and uncooked samples, nine dairy products, 17 infant or adult-feeding solutions and 48 plant foods (including vegetables, nuts or seeds, fruits and legumes. Taurine was detected in meats, dairy products, and infant feeding solutions but not in plant products or adult feeding solutions. Using these data, we compared calculated and measured daily taurine intakes in six defined diets. We present sample daily diets for omnivores, lacto-ovovegetarians and vegans (strict vegetarians), together with calculated taurine intakes.     

Zinc intake and status in Australian vegetarians

Vegetarians have a lower incidence of many chronic diseases than omnivores. However, vegetarian diets could potentially result in lower intakes of some minerals, particularly Zn. In a cross-sectional study, dietary Zn intake was measured using 12 d weighed records in ninety-nine vegetarians (ten vegans) aged 18-50 years and forty-nine age- and sex-matched omnivores. In men, the mean daily Zn intake and Zn density values were similar in omnivores, ovolactovegetarians and vegans, but in women they were significantly lower in vegetarians (mean intake 6.8 mg v. 8.4 mg in omnivores) and few achieved the recommended intake. Significantly more vegetarian than omnivorous women had a daily Zn intake < 6 mg (44% v. 13%). Mean serum Zn concentrations were similar in female omnivores and vegetarians, despite the differences in intake. However, omnivorous men had a lower mean serum Zn concentration (0.85 microgram/ml v. 0.95 microgram/ml) and more subjects had levels below the reference range of 0.72-1.44 micrograms/ml than ovolactovegetarians (P < 0.01). Overall more women than men had low Zn concentrations; and these women generally had intakes below 6 mg/d. There was a significant correlation between serum Zn concentration and dietary Zn density in vegetarians, especially females (P < 0.001), but not in omnivores. Ovolactovegetarians did not have a significantly greater risk of low Zn status than omnivores.     

Young Swedish vegans have different sources of nutrients than young omnivores

The aim of this study was to identify sources of nutrients in diets of young Swedish vegans and omnivores. Three months of dietary intakes were investigated by diet history interviews. Volunteers were recruited through advertising and visits to schools in the city of Ume?, Sweden. Thirty vegans, 15 female and 15 male, aged 17.5+/-1.0 years, were compared with 30 sex-, age-, and height-matched omnivores. Vegans had different sources of nutrients than young omnivores and relied to a great extent on dietary supplements as a source of vitamin B-12, vitamin D, calcium, and selenium. Dietary intake of vegetables, fruits, and berries exceeded 500 g/day for 21 of the 30 vegans, whereas the same held true for only 1 of the 30 omnivores. Instead of animal products, young vegans rely on dietary supplements, legumes, vegetables, fruits, and berries as sources of nutrients.     

Dietary intake and nutritional status of young vegans and omnivores in Sweden

BACKGROUND: Adolescents sometimes become vegetarian for ethical rather than health reasons. This may result in health problems caused by lack of interest in and knowledge of nutrition. OBJECTIVE: We compared the dietary intake and nutritional status of young Swedish vegans and omnivores. DESIGN: The dietary intakes of 30 vegans (15 males and 15 females; mean age: 17.5 +/- 1.0 y) and 30 sex-, age-, and height-matched omnivores were assessed with the use of a diet-history interview and validated by the doubly labeled water method and by measuring nitrogen, sodium, and potassium excretion in urine. Iron status and serum vitamin B-12 and folate concentrations were measured in blood samples. RESULTS: The diet-history method underestimated energy intake by 13% and potassium intake by 7% compared with the doubly labeled water method and 24-h urine excretion, respectively. Reported dietary nitrogen and sodium intakes agreed with the 24-h urinary excretion measure. Vegans had higher intakes of vegetables, legumes, and dietary supplements and lower intakes of cake and cookies and candy and chocolate than did omnivores. Vegans had dietary intakes lower than the average requirements of riboflavin, vitamin B-12, vitamin D, calcium, and selenium. Intakes of calcium and selenium remained low even with the inclusion of dietary supplements. There was no significant difference in the prevalence of low iron status among vegans (20%) and omnivores (23%). Two vegans with low intakes of vitamin B-12 had low serum concentrations. CONCLUSION: The dietary habits of the vegans varied considerably and did not comply with the average requirements for some essential nutrients.     

Nutrient intake and iron status of Australian male vegetarians

OBJECTIVE: The study was designed to investigate the iron intake and status of Australian, male vegetarians aged between 20 and 50 y. DESIGN: Cross-sectional comparison of male vegetarians and age/sex matched omnivores. SETTING: Free-living community subjects. SUBJECTS: 39 ovolactovegetarians, 10 vegans and 25 omnivores were recruited by local advertisement. OUTCOME MEASURES: A 12-d semiquantitative dietary record to assess iron and zinc intake. Iron status was assessed by measurement of serum ferritin and haemoglobin concentrations. RESULTS: Mean (s.d.) daily iron intakes of both the ovolactovegetarians (20.4 (7.7) mg/d) and vegans (22.9 (6.2) mg/d), were significantly higher than the omnivores' intake of 15.8 (4.5) mg/d. Ovo-lactovegetarians and vegans had significantly (P < 0.001 and P < 0.05, respectively) lower serum ferritin concentrations than omnivores: mean (s.d.): 64 (46.9), 65 (49.9) and 121 (72.5) ng/ml, respectively. Significantly more ovolactovegetarians and vegans than omnivores had serum ferritin concentrations below 25 ng/ml and below 12 ng/ml (P < 0.05). A higher proportion of omnivores had concentrations above 200 ng/ml (P < 0.05). The differences in serum ferritin concentrations between the vegetarians and omnivores remained significant even after exclusion of iron supplement users. CONCLUSION: Australian male vegetarians had iron intakes higher than those of omnivores and above recommended levels, but their iron status was significantly lower.     

Comparison of Five Oxidative Stress Biomarkers in Vegans and Omnivores from Germany and Finland

When the amount of reactive oxygen species produced by human metabolism cannot be balanced by antioxidants, this phenomenon is commonly referred to as oxidative stress. It is hypothesised that diets with high amounts of plant food products may have a beneficial impact on oxidative stress status. However, few studies have examined whether a vegan diet is associated with lower oxidative stress compared to an omnivorous diet. The present cross-sectional study aimed to compare the levels of five oxidative stress biomarkers in vegans and omnivores. Data of 36 vegans and 36 omnivores from Germany and of 21 vegans and 18 omnivores from Finland were analysed. HPLC coupled with mass spectrometry or fluorescence detection and ELISA methods were used to measure the oxidative stress biomarkers malondialdehyde (MDA), protein carbonyls and 3-nitrotyrosine in plasma and 8-hydroxy-2′-deoxyguanosine (8-OHdG) and 8-iso-prostaglandin F2α (8-iso-PGF2α) in 24 h urine. Analyses of variance and covariance, considering potential confounders, were used. Vegans and omnivores showed no differences in MDA and protein carbonyl concentrations. In Finnish but not in German vegans, the concentrations of 3-nitrotyrosine were lower compared to those in omnivores (p = 0.047). In Germany, vegans showed lower excretion levels of 8-iso-PGF2α than omnivores (p = 0.002) and with a trend also of 8-OHdG (p = 0.05). The sensitivity analysis suggests lower 8-iso-PGF2α excretion levels in women compared to men, independently of the dietary group. The present study contributes to expanding our knowledge of the relationship between diet and oxidative stress and showed that 3-nitrotyrosine, 8-OHdG and 8-iso-PGF2α tended to be lower in vegans. Furthermore, studies are recommended to validate the present findings.     

Validity of reported energy expenditure and energy and protein intakes in Swedish adolescent vegans and omnivores

BACKGROUND: It is difficult to obtain accurate reports of dietary intake; therefore, reported dietary intakes must be validated. Researchers need low-cost methods of estimating energy expenditure to validate reports of energy intake in groups with different lifestyles and eating habits. OBJECTIVE: We sought to validate the reported energy expenditure and energy and protein intakes of Swedish adolescent vegans and omnivores. DESIGN: We compared 16 vegans (7 females and 9 males; mean age: 17.4 +/- 0.8 y) with 16 omnivores matched for sex, age, and height. Energy expenditure as reported in a physical activity interview and energy and protein intakes as reported by diet history were validated by using the doubly labeled water method and by measuring urinary nitrogen excretion. RESULTS: The validity of reported energy expenditure and energy and protein intakes was not significantly different between vegans and omnivores. The physical activity interview had a bias toward underestimating energy expenditure by 1.4 +/- 2.6 MJ/d (95% CI: 2.4, 0.5 MJ/d). The diet-history interview had a bias toward underestimating energy intake by 1.9 +/- 2.7 MJ/d (95% CI: 2.9, 1.0 MJ/d) but showed good agreement with the validation method for nitrogen (protein) intake (underestimate of 0.40 +/- 1.90 g N/d; 95% CI: 1.10, 0.29 g N/d). CONCLUSIONS: The physical activity and diet-history interviews underestimated energy expenditure and energy intake, respectively. Energy intake and expenditure were underestimated to the same extent, and the degree of underestimation was not significantly different between vegans and omnivores. Valid protein intakes were obtained with the diet-history method for both vegans and omnivores.     

Testosterone, sex hormone-binding globulin, calculated free testosterone, and oestradiol in male vegans and omnivores

Total testosterone (T), total oestradiol (E2) and sex hormone-binding globulin (SHBG) concentrations were measured in plasma samples from fifty-one male vegans and fifty-seven omnivores of similar age. Free T concentration was estimated by calculation. In comparison with the omnivores, the vegans had 7% higher total T (P = 0.250), 23% higher SHBG (P = 0.001), 3% lower free T (P = 0.580), and 11% higher E2 (P = 0.194). In a subset of eighteen vegans and twenty-two omnivores for whom 4 d diet records were available, there were statistically significant correlations between T and polyunsaturated fatty acids (r 0.37), SHBG and fat (r 0.43 for total fat, 0.46 for saturated fatty acids and 0.33 for polyunsaturated fatty acids), and SHBG and alcohol (r-0.39). It is concluded that a vegan diet causes a substantial increase in SHBG but has little effect on total or free T or on E2.     

Long-chain n-3 polyunsaturated fatty acids in plasma in British meat-eating, vegetarian, and vegan men

BACKGROUND: Plasma concentrations of long-chain n-3 polyunsaturated fatty acids are lower in vegetarians and in vegans than in omnivores. No data are available on whether these concentrations differ between long- and short-term vegetarians and vegans. OBJECTIVES: We compared plasma fatty acid composition in meat-eaters, vegetarians, and vegans and examined whether the proportions of eicosapentaenoic acid (20:5n-3; EPA), docosapentaenoic acid (22:5n-3; DPA), and docosahexaenoic acid (22:6n-3; DHA) were related to the subjects' duration of adherence to their diets or to the proportions of plasma linoleic acid (18:2n-6; LA) and alpha-linolenic acid (18:3n-3; ALA). DESIGN: The present cross-sectional study included 196 meat-eating, 231 vegetarian, and 232 vegan men in the United Kingdom. Information on anthropometry, diet, and smoking habits was obtained through a questionnaire. Total fatty acid composition in plasma was measured. RESULTS: The proportions of plasma EPA and DHA were lower in the vegetarians and in the vegans than in the meat-eaters, whereas only small differences were seen for DPA. Plasma EPA, DPA, and DHA proportions were not significantly associated with the duration of time since the subjects became vegetarian or vegan, which ranged from <1 y to >20 y. In the vegetarians and the vegans, plasma DHA was inversely correlated with plasma LA. CONCLUSIONS: The proportions of plasma long-chain n-3 fatty acids were not significantly affected by the duration of adherence to a vegetarian or vegan diet. This finding suggests that when animal foods are wholly excluded from the diet, the endogenous production of EPA and DHA results in low but stable plasma concentrations of these fatty acids.     

Short- and Branched-Chain Fatty Acids as Fecal Markers for Microbiota Activity in Vegans and Omnivores

A vegan diet could impact microbiota composition and bacterial metabolites like short-chain (SCFA) and branched-chain fatty acids (BCFA). The aim of this study was to compare the concentrations of SCFA, BCFA, ammonia, and fecal pH between vegans and omnivores. In this cross-sectional study (vegans n = 36; omnivores n = 36), microbiota composition, fecal SCFA, BCFA, and ammonia concentrations and pH were analyzed in complete stool samples. A random forest regression (RFR) was used to identify bacteria predicting SCFA/BCFA concentrations in vegans and omnivores. No significant differences in SCFA and BCFA concentrations were observed between vegans and omnivores. Fecal pH (p = 0.005) and ammonia concentration (p = 0.01) were significantly lower in vegans than in omnivores, while fiber intake was higher (p < 0.0001). Shannon diversity was higher in omnivores compared to vegans on species level (p = 0.04) only. In vegans, a cluster of Faecalibacterium prausnitzii, Prevotella copri, Dialister spp., and Eubacterium spp. was predictive for SCFA and BCFA concentrations. In omnivores, Bacteroides spp., Clostridium spp., Ruminococcus spp., and Prevotella copri were predictive. Though SCFA and BCFA did not differ between vegans and omnivores, the results of the RFR suggest that bacterial functionality may be adapted to varying nutrient availability in these diets.     

Platelet phospholipid fatty acid composition and function in vegans compared with age- and sex-matched omnivore controls.

Platelet function and phospholipid composition, plasma lipids and dietary intakes were assessed in 20 vegan subjects and 20 age- and sex-matched omnivore controls. The intakes of saturated fat were lower in the vegans and those of linoleic and linolenic acids were greater. Eicosapentaenoic and docosahexaenoic acids were absent from the diets of the vegans. Plasma total cholesterol and low-density lipoprotein concentrations were lower in the male vegan subjects and those of carotene were greater compared with their controls. The platelet phospholipids of the vegans contained higher proportions of linoleic (18:2n-6) and adrenic (22:4n-6) acids and lower proportions of arachidonic (20:4n-6), eicosapentaenoic (20:5n-3), docosapentaenoic (22:5n-3) and docosahexaenoic (22:6n-3) acids. Template bleeding times, platelet aggregation induced by adenosine diphosphate, compound U44619 and collagen were similar in both groups.     

Vegan Diet and Bone Health—Results from the Cross-Sectional RBVD Study

Scientific evidence suggests that a vegan diet might be associated with impaired bone health. Therefore, a cross-sectional study (n = 36 vegans, n = 36 omnivores) was used to investigate the associations of veganism with calcaneal quantitative ultrasound (QUS) measurements, along with the investigation of differences in the concentrations of nutrition- and bone-related biomarkers between vegans and omnivores. This study revealed lower levels in the QUS parameters in vegans compared to omnivores, e.g., broadband ultrasound attenuation (vegans: 111.8 ± 10.7 dB/MHz, omnivores: 118.0 ± 10.8 dB/MHz, p = 0.02). Vegans had lower levels of vitamin A, B2, lysine, zinc, selenoprotein P, n-3 fatty acids, urinary iodine, and calcium levels, while the concentrations of vitamin K1, folate, and glutamine were higher in vegans compared to omnivores. Applying a reduced rank regression, 12 out of the 28 biomarkers were identified to contribute most to bone health, i.e., lysine, urinary iodine, thyroid-stimulating hormone, selenoprotein P, vitamin A, leucine, α-klotho, n-3 fatty acids, urinary calcium/magnesium, vitamin B6, and FGF23. All QUS parameters increased across the tertiles of the pattern score. The study provides evidence of lower bone health in vegans compared to omnivores, additionally revealing a combination of nutrition-related biomarkers, which may contribute to bone health. Further studies are needed to confirm these findings.     

Influence of habitual diet on antioxidant status: a study in a population of vegetarians and omnivores

BACKGROUND: Antioxidant status can be used as a biomarker to assess chronic disease risk and diet can modulate antioxidant defence. OBJECTIVE: To examine effects of vegetarian diet and variations in the habitual intakes of foods and nutrients on blood antioxidants. SUBJECTS AND SETTING: Thirty-one vegetarians (including six vegans) and 58 omnivores, non-smokers, in Northern Ireland. DESIGN: A diet history method was used to assess habitual diet. Antioxidant vitamins, carotenoids, uric acid, zinc- and ferric-reducing ability of plasma (FRAP) were measured in fasting plasma and activities of glutathione peroxidase (GPX), superoxide dismutase (SOD) and glutathione S-transferase (GST) and level of reduced glutathione (GSH) were measured in erythrocytes. RESULTS: Vegetarians had approximately 15% higher levels of plasma carotenoids compared with omnivores, including lutein (P< or =0.05), alpha-cryptoxanthin P< or =0.05), lycopene (NS), alpha-carotene (NS) and beta-carotene (NS). The levels/activities of all other antioxidants measured were similar between vegetarians and omnivores. Total intake of fruits, vegetables and fruit juices was positively associated with plasma levels of several carotenoids and vitamin C. Intake of vegetables was positively associated with plasma lutein, alpha-cryptoxanthin, alpha-carotene and beta-carotene, whereas intake of fruits was positively associated with plasma beta-cryptoxanthin. Intake of tea and wine was positively associated with FRAP value, whereas intake of herbal tea associated positively with plasma vitamin C. Intakes of meat and fish were positively associated with plasma uric acid and FRAP value. CONCLUSIONS: The overall antioxidant status was similar between vegetarians and omnivores. Good correlations were found between intakes of carotenoids and their respective status in blood.     

Risk of overweight and obesity among semivegetarian, lactovegetarian, and vegan women

BACKGROUND: Observational studies suggest that a plant-based diet is inversely related to body mass index (BMI), overweight, and obesity. OBJECTIVE: Our objective was to examine the BMI (kg/m(2)) and risk of overweight and obesity of self-defined semivegetarian, lactovegetarian, and vegan women. DESIGN: Data analyzed in this cross-sectional study were from 55459 healthy women participating in the Swedish Mammography Cohort. Women were asked whether they considered themselves to be omnivores (n = 54257), semivegetarians (n = 960), lactovegetarians (n = 159), or vegans (n = 83), and this question was the main exposure variable in this study. In secondary analyses, we reclassified women as lactovegetarians on the basis of food intakes reported on the food-frequency questionnaire. RESULTS: The prevalence of overweight or obesity (BMI >/= 25) was 40% among omnivores, 29% among both semivegetarians and vegans, and 25% among lactovegetarians. In multivariate, adjusted logistic regression analyses, self-identified vegans had a significantly lower risk of overweight or obesity [odds ratio (OR) = 0.35; 95% CI: 0.18, 0.69] than did omnivores, as did lactovegetarians (OR = 0.54; 95% CI: 0.35, 0.85) and semivegetarians (OR = 0.52; 95% CI: 0.43, 0.62). Risk of overweight or obesity remained significantly lower among lactovegetarians classified on the basis of the food-frequency questionnaire (OR = 0.48; 95% CI: 0.30, 0.78). CONCLUSIONS: Even if vegetarians consume some animal products, our results suggest that self-identified semivegetarian, lactovegetarian, and vegan women have a lower risk of overweight and obesity than do omnivorous women. The advice to consume more plant foods and less animal products may help individuals control their weight.     

Raised thyroid stimulating hormone associated with kelp intake in British vegan men

To explore the hypothesis that the iodine intake of vegans might be inadequate, thyroid stimulating hormone concentrations were measured in plasma samples from 101 British men, of whom 48 were vegans and 53 were omnivores. The geometric mean thyroid stimulating hormone concentration, adjusted for age and body mass index, was 47% higher in the vegans than in the omnivores (P= 0.001). Five vegans but none of the omnivores had a thyroid stimulating hormone concentration above the reference upper limit of 5 mU/1 (P=0.022). High concentrations of thyroid stimulating hormone are usually indicative of marginal iodine status, but can also result from excessive iodine intake. The three vegans with the highest values of thyroid stimulating hormone reported regular use of kelp tablets or kelp powder. None of the other vegans, and none of the omnivores, reported taking kelp. After exclusion of the three vegans who took kelp, the remaining vegans had an adjusted geometric mean thyroid stimulating hormone concentration 29% higher than that of the omnivores (P=0.012). It was concluded that use of kelp can be associated with raised thyroid stimulating hormone, and that the iodine status of vegans who do not use kelp requires further investigation.     

Effect of dietary taurine on plasma and blood cell taurine concentrations in cats

Taurine levels were measured in adult cats consuming casein-based diets supplemented with 0.2, 0.05, 0.02, 0.01 or 0% (wt/wt) taurine or with 0% taurine plus 5.0% L-cystine. Taurine concentrations in plasma, platelets, granulocytes and erythrocytes declined significantly with decreased dietary taurine. In the cats that did not receive the 5.0% cystine supplement, the relationship between dietary taurine intake and plasma and blood cell taurine level was nonlinear. The greatest increment in taurine concentrations occurred between the 0.02 and 0.05% taurine intakes. These findings suggest that the dietary taurine requirement for adult cats may be between 0.02 and 0.05%. Supplementation of the 0% taurine diet with 5.0% L-cystine raised taurine levels above those of the taurine-deficient diets in plasma and all blood cell types. The result of this study therefore suggest a close relationship between dietary taurine intake and blood cell taurine levels in cats. Five percent L-cystine stimulates taurine synthesis in these animals.     

Designing Nutritionally Adequate and Climate-Friendly Diets for Omnivorous,Pescatarian, Vegetarian and Vegan Adolescents in Sweden Using Linear Optimization

Low-carbon diets can counteract climate change and promote health if they are nutritionally adequate, affordable and culturally acceptable. This study aimed at developing sustainable diets and to compare these with the EAT-Lancet diet. The Swedish national dietary survey Riksmaten Adolescents 2016–2017 was used as the baseline. Diets were optimized using linear programming for four dietary patterns: omnivores, pescatarians, vegetarians and vegans. The deviation from the baseline Riksmaten diet was minimized for all optimized diets while fulfilling nutrient and climate footprint constraints. Constraining the diet-related carbon dioxide equivalents of omnivores to 1.57 kg/day resulted in a diet associated with a reduction of meat, dairy products, and processed foods and an increase in potatoes, pulses, eggs and seafood. Climate-friendly, nutritionally adequate diets for pescatarians, vegetarians and vegans contained fewer foods and included considerable amounts of fortified dairy and meat substitutes. The optimized diets did not align very well with the food-group pattern of the EAT-Lancet diet. These findings suggest how to design future diets that are climate-friendly, nutritionally adequate, affordable, and culturally acceptable for Swedish adolescents with different dietary patterns. The discrepancies with the EAT diet indicate that the cultural dietary context is likely to play an important role in characterizing sustainable diets for specific populations.     

Taiwanese vegetarians have higher insulin sensitivity than omnivores

The present study was designed to examine the effects of habitual consumption of Taiwanese vegetarian diets on hormonal secretion, and on lipid and glycaemic control. Of the ninety-eight healthy female adults recruited from Hualien, Taiwan (aged 31-45 years), forty-nine were Buddhist lactovegetarians and forty-nine were omnivores. Dietary intakes were measured, and blood levels of nutrients and hormones were analysed. Vegetarians consumed less energy, fat and protein, but more fibre than the omnivores. Compared with the omnivores, the vegetarians had, on average, lower BMI and smaller waist circumference. Except for slightly lower levels of thyroxine (T4) in vegetarians, vegetarians and omnivores both showed similar levels of triiodothyronine (T3), free T4, thyroid-stimulating hormone, T3:T4 ratio and cortisol. Compared with the omnivores, the vegetarians had significantly lower levels of fasting insulin (median: 35.3 v. 50.6 pmol/l) and plasma glucose (mean: 4.7 (se 0.05) v. 4.9 (se 0.05) mmol/l). Insulin resistance, as calculated by the homeostasis model assessment method, was significantly lower in the vegetarians than in the omnivores (median: 1.10 v. 1.56), while beta-cell function was not different between the two groups. BMI and diet were both independent predictors for insulin resistance, and contributed 18 and 15 % of the variation in insulin resistance, respectively. In conclusion, Taiwanese vegetarians had lower glucose and insulin levels and higher insulin sensitivity than did the omnivores. Diet and lower BMI were partially responsible for the high insulin sensitivity observed in young Taiwanese vegetarians.     

Assessment of iodine intake in vegans: weighed dietary record vs duplicate portion technique

OBJECTIVE: To compare iodine intakes estimated from weighed dietary records with iodine intakes obtained by direct analysis of duplicate diets in a group of vegans. DESIGN: Cross-sectional study. SETTING: London and the south-east of England. SUBJECTS: Thirty-three vegans consuming their habitual diet were recruited through the UK Vegan Society; 26 subjects (11 males, 15 females), age 21-84 y, completed the study. INTERVENTIONS: Iodine intakes were estimated from 4 day weighed dietary records and compared with iodine intakes obtained by direct analysis of concurrent 4 day duplicate diets. RESULTS: There was wide variation in iodine intakes. Mean daily iodine intake in males was significantly lower (P<0.05) when estimated from dietary records (42 microg) compared with that analysed from duplicate diets (137 microg). Conversely, in females the mean daily iodine intake from dietary records (1448 microg) was higher (P=0.43) than from duplicate diets (216 microg). Variation in iodine intakes determined by the two different methods may be attributed to the absence of iodine content of some foods, in particular foods suitable for vegan consumption, in food composition tables and the variability in iodine content of seaweed. CONCLUSIONS: The use of current food tables to estimate iodine intake in vegans is limited. It is not always practical to determine iodine intake using the duplicate portion technique, therefore more reliable information on iodine content of foods, incorporating the variation within foods, is needed.     

Dietary intake and nutritional status of vegetarian and omnivorous preschool children and their parents in Taiwan

The aim of this study was to assess and compare dietary intake and nutritional status of vegetarian and omnivorous preschool children and their parents. Fifty-six omnivores (28 children and 28 parents) and 42 vegetarians (21 preschool children with 18 lacto-ovo-vegetarians and 3 ovo-vegetarians; 21 parents with 16 lacto-ovo-vegetarians, 2 ovo-vegetarians, 1 lacto-vegetarian, and 2 vegans) were recruited. Anthropometric measurements were taken; body mass index and weight-for-height index (WHI) were calculated. Nutrient intake was recorded using 3-day dietary records. Fasting venous blood samples were obtained to estimate hematologic and vitamin status parameters. Height, weight, body mass index, WHI, and triceps skinfold thickness value differences between omnivores and vegetarians in both parent and child groups were not found. Both omnivorous parents and their children had significantly higher fat and lower fiber intakes than vegetarian parents and children. Omnivorous children had significantly higher protein and lower vitamin C intakes than vegetarian children, whereas omnivorous parents had significantly lower vitamin A and iron intakes than vegetarian parents. Vegetarians and omnivores in both parent and child groups had mean calcium consumption less than 75% of the Taiwan dietary intakes. All mean hematologic and biochemical nutrient status indices were within the reference range in any groups. However, both vegetarian parents and children had significantly lower mean total cholesterol and serum ferritin concentrations than those of omnivorous parents and children. Our vegetarian and omnivorous preschool children had normal growth and adequate nutritional status. However, both parents and children had inadequate calcium intakes, which may potentially affect bone health, especially for preschool children in the growing stage.