Relative Weight,Weight Loss Efforts and Nutrient Intakes among Health-Conscious Vegetarian,Past Vegetarian and Nonvegetarian Women Ages 18 to 50.

Objective: To compare relative weight, weight loss efforts and nutrient intakes among similarly health-conscious vegetarian, past vegetarian and nonvegetarian premenopausal women.

Methods: Demographic data, lifestyle practices and weight loss efforts (by questionnaire), body mass index (BMI;kg/m²) and dietary intake (via multiple-pass 24-hour diet recall) were compared in a convenience sample of 90 current vegetarians, 35 past vegetarians and 68 nonvegetarians.

Results: Age (31.9 ± 8.8), educational attainment, smoking status, alcohol use, physical activity and perceived health status were similar among the three groups of women. BMI did not differ by dietary pattern and averaged 23.7 ± 4.7 for all women combined. Participants had intentionally lost ≥ 10 pounds a mean of 2.1 times, and 39% of women perceived themselves to be overweight; again, no differences were observed among dietary groups. Dietary intakes of vegetarians and current nonvegetarians were consistent with current recommendations for macronutrient composition (<30% fat, <10% saturates). Compared to current nonvegetarians, current vegetarians had lower intakes of protein, saturated fat, cholesterol, niacin, vitamins B₁₂ and D, and higher fiber and magnesium intakes. Vegetarians’ mean vitamin B₁₂ and D intakes were well below recommendations.

Conclusions: Relative weight and weight loss efforts do not differ by dietary pattern among similarly health-conscious vegetarian and nonvegetarian women. The only differences in nutrient intake with potential health implications were vitamins D and B₁₂.     

Relative weight, weight loss efforts and nutrient intakes among health-conscious vegetarian, past vegetarian and nonvegetarian women ages 18 to 50

OBJECTIVE: To compare relative weight, weight loss efforts and nutrient intakes among similarly health-conscious vegetarian, past vegetarian and nonvegetarian premenopausal women. METHODS: Demographic data, lifestyle practices and weight loss efforts (by questionnaire), body mass index (BMI;kg/m2) and dietary intake (via multiple-pass 24-hour diet recall) were compared in a convenience sample of 90 current vegetarians, 35 past vegetarians and 68 nonvegetarians. RESULTS: Age (31.9 +/- 8.8), educational attainment, smoking status, alcohol use, physical activity and perceived health status were similar among the three groups of women. BMI did not differ by dietary pattern and averaged 23.7 +/- 4.7 for all women combined. Participants had intentionally lost > or = 10 pounds a mean of 2.1 times, and 39% of women perceived themselves to be overweight; again, no differences were observed among dietary groups. Dietary intakes of vegetarians and current nonvegetarians were consistent with current recommendations for macronutrient composition (< 30% fat, < 10% saturates). Compared to current nonvegetarians, current vegetarians had lower intakes of protein, saturated fat, cholesterol, niacin, vitamins B12 and D, and higher fiber and magnesium intakes. Vegetarians' mean vitamin B12 and D intakes were well below recommendations. CONCLUSIONS: Relative weight and weight loss efforts do not differ by dietary pattern among similarly health-conscious vegetarian and nonvegetarian women. The only differences in nutrient intake with potential health implications were vitamins D and B12.     

A vegetarian dietary pattern as a nutrient-dense approach to weight management: an analysis of the national health and nutrition examination survey 1999-2004

Background

Population-based studies have shown that vegetarians have lower body mass index than nonvegetarians, suggesting that vegetarian diet plans may be an approach for weight management. However, a perception exists that vegetarian diets are deficient in certain nutrients.

Objective

To compare dietary quality of vegetarians, nonvegetarians, and dieters, and to test the hypothesis that a vegetarian diet would not compromise nutrient intake when used to manage body weight.

Design

Cross-sectional analysis of National Health and Nutrition Examination Survey (1999-2004) dietary and anthropometric data. Diet quality was determined using United States Department of Agriculture's Healthy Eating Index 2005. Participants included adults aged 19 years and older, excluding pregnant and lactating women (N=13,292). Lacto-ovo vegetarian diets were portrayed by intakes of participants who did not eat meat, poultry, or fish on the day of the survey (n=851). Weight-loss diets were portrayed by intakes of participants who consumed 500 kcal less than their estimated energy requirements (n=4,635). Mean nutrient intakes and body mass indexes were adjusted for energy, sex, and ethnicity. Using analysis of variance, all vegetarians were compared to all nonvegetarians, dieting vegetarians to dieting nonvegetarians, and nondieting vegetarians to nondieting nonvegetarians.

Results

Mean intakes of fiber, vitamins A, C, and E, thiamin, riboflavin, folate, calcium, magnesium, and iron were higher for all vegetarians than for all nonvegetarians. Although vegetarian intakes of vitamin E, vitamin A, and magnesium exceeded that of nonvegetarians (8.3±0.3 vs 7.0±0.1 mg; 718±28 vs 603±10 μg; 322±5 vs 281±2 mg), both groups had intakes that were less than desired. The Healthy Eating Index score did not differ for all vegetarians compared to all nonvegetarians (50.5±0.88 vs 50.1±0.33, P=0.6).

Conclusions

These findings suggest that vegetarian diets are nutrient dense, consistent with dietary guidelines, and could be recommended for weight management without compromising diet quality.     

Dietary intakes and nutrient status of vegetarian preschool children from a British national survey

Background Dietary intakes and nutrient status were compared in meat‐eaters and non‐meat‐eaters from the National Diet and Nutrition Survey of children aged 1.5–4.5 years. Methods Children (n = 1351) were categorized as ‘omnivores’ or ‘vegetarians’, according to whether they consumed meat or meat products during a 4‐day dietary record. Blood samples were also obtained for analysis of haematological and biochemical nutrient status. Results Three per cent of children were ‘vegetarian’. They consumed higher proportions of milk and milk products, although this was significant only in older children (P = 0.007), owing to high consumption by the high proportion of Asian children. In vegetarians, energy intakes tended to be lower in both age groups. Percentage energy from protein and fat were lower, while that from carbohydrate was higher compared with omnivores. Cholesterol intakes were lower, significantly so for younger children (P < 0.001). Intakes of micronutrients were either higher (vitamins C and E, potassium) or lower (niacin and sodium) in younger vegetarians compared with omnivores. Energy‐adjusted intakes of iron and zinc did not differ significantly from those of omnivores, although both intakes were low in many children (6–20% < LRNI), particularly in the younger group. Haematological and biochemical nutrient status indices showed few differences. Serum ferritin was lower in vegetarians, significantly so in younger children (P = 0.002). Antioxidant vitamin (A, C and E) status tended to be higher in vegetarians, while vitamin B₁₂ intakes and status were more than adequate. Apart from poorer vitamin D intake and status in older Asian vegetarians, very few ethnic differences were observed. Conclusions Nutrient intakes and status were generally adequate in preschool children who did not eat meat. Although serum ferritin levels were inferior (particularly in vegetarians under 3 years old), the lower intakes of fat, cholesterol and sodium, and higher antioxidant vitamin intakes and status indices were potentially beneficial. Given a balanced diet, adequate nutrient intakes and status can be maintained without consuming meat.     

The influence of a wide range of absorbed cholesterol on plasma cholesterol levels in man

The influence of absorbed dietary cholesterol on plasma cholesterol concentration was studied in two populations, one Seventh Day Adventist (SDA) vegetarian and one nonvegetarian, representing a broad range of plasma cholesterol values and dietary cholesterol intakes. As a group, the SDA vegetarians had significantly lower levels of plasma cholesterol and triglycerides than did the nonvegetarians. This hypolipidemic pattern in the SDA vegetarians was apparently closely related to dietary habits, sinceanother group of SDA who were nonvegetarian had significantly higher plasma cholesterol and triglyceride levels than their vegetarian counterparts. Both the dietary intake of cholesterol and the percentage absorption of cholesterol were lower in vegetarians than in nonvegetarians. The mass of cholesterol absorbed increased linearly with the mass of cholesterol ingested in all groups, but no relationship could be demonstrated between absorbed cholesterol and plasma cholesterol concentration.     

Vegetarian nutrition

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Dietary intake and iron status of Australian vegetarian women.

BACKGROUND: Despite the possible overall health benefits of a vegetarian diet, there is concern that some vegetarians and infrequent meat eaters, particularly females, may have inadequate iron status because of low or no heme-iron intakes. OBJECTIVE: The objective was to investigate the nutritional intake and iron status of vegetarian women. DESIGN: The nutritional intakes of 50 free-living vegetarian women aged 18-45 y and 24 age-matched omnivorous control women were assessed by using 12-d weighed dietary records. Iron status was assessed by measuring hemoglobin and serum ferritin concentrations. RESULTS: There was no significant difference between mean (+/-SD) daily iron intakes of vegetarians and omnivores (10.7 +/- 4.4 and 9.9 +/- 2.9 mg, respectively), although heme-iron intakes were low in the vegetarians. Vegetarians had significantly lower intakes of protein (P < 0.01), saturated fat (P < 0.01), and cholesterol (P < 0.001), and significantly higher intakes of dietary fiber (P < 0.001) and vitamin C (P < 0.05). Mean serum ferritin concentrations were significantly lower (P = 0.025) in vegetarians (25.0 +/- 16.2 microg/L) than in omnivores (45.5 +/- 42.5 microg/L). However, similar numbers of vegetarians (18%) and omnivores (13%) had serum ferritin concentrations <12 microg/L, which is a value often used as an indicator of low iron stores. Hemoglobin concentrations were not significantly different. CONCLUSION: It is important that both vegetarian and omnivorous women maintain an adequate iron status and follow dietary practices that enhance iron absorption.     

Perceptions and practices of self-defined current vegetarian, former vegetarian, and nonvegetarian women

OBJECTIVE: To assess the diversity of vegetarians' dietary practices and how they change over time, and to explore perceptions of meat and dairy products among vegetarians, former vegetarians, and nonvegetarians. DESIGN: Cross-sectional survey; qualitative interviews with a subsample. SUBJECTS/SETTING: Ninety self-defined current vegetarian, 35 former vegetarian and 68 nonvegetarian women in Vancouver, British Columbia. A subsample of 15 subjects completed qualitative interviews. STATISTICAL ANALYSIS PERFORMED: Group comparisons using 1-way analysis of variance with post-hoc testing for continuous variables, chi2 for categorical variables. RESULTS: Of 90 current vegetarians, 51 and 14 reported occasional use of fish or chicken respectively. Fifty-six vegetarians, including 4 of 6 vegans, reported that their diets had become more restrictive over time, and 48 planned additional changes, most frequently a reduction in dairy product use. Reasons cited by former vegetarians for resuming omnivorous diets included: not feeling healthy, concern about their nutritional status, a change in living situation, or missing the taste of meat. Perceptions of meat and dairy products differed significantly by dietary pattern: nonvegetarians and former vegetarians were more likely than current vegetarians to agree with statements inferring positive attributes (eg, nutrient content). In contrast, more current and former vegetarians than nonvegetarians agreed with statements inferring negative attributes (eg, presence of contaminants). APPLICATIONS/CONCLUSIONS: Dietitians who counsel women need to be aware of the heterogeneity of dietary practices and beliefs regarding use of animal products to provide advice appropriate to each individual. At a broader level, addressing women's food safety and animal welfare concerns will likely require collaboration among food industry and government, health, and consumer agencies.     

Nutrient Intake and Status of German Children and Adolescents Consuming Vegetarian,Vegan or Omnivore Diets: Results of the VeChi Youth Study

There is a lack of data on associations between modern vegetarian and vegan diets and health among children and adolescents. The aim of the Vechi Youth Study was to cross-sectionally examine anthropometry, dietary intakes and nutritional status in a sample of 149 vegetarian, 115 vegan and 137 omnivore children and adolescents (6–18 years old, mean age: 12.7 ± 3.9 years). Group differences of dietary intake (calculated from three-day dietary records), nutrient biomarker and blood lipid concentrations were assessed using an analysis of covariance, adjusted for sex, age and other covariates. The total energy intake did not differ significantly between groups, but intake of carbohydrates was higher among vegetarians and vegans than among omnivores (p = 0.0002, respectively). The median protein intake exceeded 0.9 g/kg body weight/day in all diet groups and was lowest among vegetarians (p < 0.02). There was no significant difference of haemoglobin, vitamin B2, 25-OH vitamin D3, HDL-C and triglycerides blood concentrations between diet groups. Vegan participants had higher folate concentrations than vegetarian participants (p = 0.0053). Ferritin concentration was significantly higher in omnivores than in vegetarians (p = 0.0134) and vegans (p = 0.0404). Vegetarians had lower concentrations of holotranscobalamin (p = 0.0042) and higher concentrations of methylmalonic acid (p = 0.0253) than omnivores. Vegans had the lowest non-HDL-C and LDL-C concentrations in comparison to vegetarians (p = 0.0053 and p = 0.0041) and omnivores (p = 0.0010 and p = 0.0010). A high prevalence (>30%) of 25-OH vitamin D3 and vitamin B2 concentrations below reference values were found irrespective of the diet group. In conclusion, the Vechi Youth Study did not indicate specific nutritional risks among vegetarian and vegan children and adolescents compared to omnivores.     

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.     

Urinary hormonal concentrations and spinal bone densities of premenopausal vegetarian and nonvegetarian women

We evaluated the relationships among nutrition, hormone concentrations, and bone density of the spine in 27 vegetarian and 37 nonvegetarian premenopausal women. The two groups were indistinguishable with respect to age, height, weight, menarche, years of formal education, and medical histories. The frequency of menstrual irregularity was significantly higher in the vegetarian group. The bone densities of the vegetarians and the nonvegetarians were not significantly different. Caffeine intake in both groups had a positive effect on urinary calcium excretion, but no association was observed between bone density and caffeine intake. Total fat, monosaturated fat, and oleic acid intake were positively associated with luteinizing hormone concentrations of the vegetarians only. Overall, the differences in dietary practices of these premenopausal vegetarian and nonvegetarian women did not appear to have major effects on bone biology or reproductive history.     

The status of plasma homocysteine and related B-vitamins in healthy young vegetarians and nonvegetarians

Summary. Background: Exclusion of animal products and having only plant protein in vegetarian diets may affect the status of certain B-vitamins, and further cause the elevation of plasma homocysteine concentration. Aim: The purpose of this study was to assess the status of homocysteine and related B-vitamins in vegetarians and nonvegetarians. The effects of biochemical parameters of B-vitamins and dietary protein on plasma homocysteine were also examined. Methods: The study was performed at the Chung Shan Medical University, Taichung, in the central part of Taiwan. Thirty-seven vegetarians (28.9 ± 5.5 y) and 32 nonvegetarians (22.9 ± 1.6 y) were recruited. Nutrient intake was recorded using 3-day dietary records. Fasting venous blood samples were obtained. Plasma homocysteine, folate and vitamin B-12 were measured. Vitamin B-6 status was assessed by direct measures [plasma pyridoxal 5'-phosphate (PLP) and urinary 4-pyridoxic acid (4-PA)] and indirect measures [erythrocyte alanine (EALT-AC) and aspartate (EAST-AC) aminotransaminase activity coefficient]. Results: There was no significant difference in vitamin B-6 intake between the two groups, although the vegetarian group had a significantly lower vitamin B-12 intake than the nonvegetarian group. Vegetarian subjects had significantly lower mean plasma PLP and vitamin B-12 concentrations than did nonvegetarian subjects (p < 0.05); however, a significantly higher mean plasma folate concentration was found in the vegetarian group. Vegetarian subjects had a significantly higher mean plasma homocysteine concentration than nonvegetarian subjects (13.2 ± 7.9 vs. 9.8 ± 2.2 μmol/L). Negative correlations were seen between plasma homocysteine and vitamin B-12 concentrations in the vegetarian (p = 0.004), nonvegetarian (p = 0.026), and pooled (p < 0.001) groups. From best subsets regression analyses, the plasma homocysteine concentration could be significantly predicted by total protein intake (p = 0.027) and plasma vitamin B-12 concentration (p = 0.005) in the pooled group. When the intake of protein is not considered, vitamin B-12 concentration is still a strong predictor of plasma homocysteine concentration (p = 0.012). Conclusions: Vitamin B-12 intake and mean plasma vitamin B-12 concentration were lower for vegetarian subjects than for nonvegetarian subjects, leading to an increase in plasma homocysteine concentration. Vitamin B-6 and folate had little effect on plasma homocysteine concentration when individuals had adequate vitamin B-6 and folate status. Received: 15 July 2002, Accepted: 24 October 2002 The study was supported by National Science Council (NSC 89–2320-B-040–046), Taiwan. Correspondence to: Y. C. Huang     

The association of dietary fat with serum cholesterol in vegetarians: the effect of dietary assessment on the correlation coefficient

The biologic relation between dietary fats and serum cholesterol established in controlled dietary studies usually has not been found in cross-sectional studies of the general population. In vegetarian groups, dietary variables and serum cholesterol have been correlated significantly. To examine the role of technique of dietary assessment versus the dietary pattern of vegetarians, the authors studied the relation of diet with total serum cholesterol in 46 predominantly vegetarian adults in the Boston, Massachusetts, area in 1973-1974. The basis of the dietary information was 10-day diet records. Total serum cholesterol was positively associated with dietary cholesterol (r = 0.53) and saturated fatty acids (r = 0.50) in partial correlation analysis adjusted for age, sex, and triceps skinfold. The use of one-day dietary records lowered these correlation coefficients to about 0.3. Analysis of the components of variation of nutrient intake demonstrated that the vegetarians had a lower within-person variance, a higher between-person variance, or both compared with nonvegetarian study groups. Biologic responsiveness to dietary fat in the vegetarians was similar to that predicted by the Keys equation derived from nonvegetarians. Therefore, multiple-day averaging of dietary records and relatively smaller ratio of within-person to between-person variation in intake favor the detection of cross-sectional associations of diet with serum cholesterol.     

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.     

Nutrient Intake and Status in Adults Consuming Plant-Based Diets Compared to Meat-Eaters: A Systematic Review

Health authorities increasingly recommend a more plant-based diet, rich in fruits, vegetables, pulses, whole grains and nuts, low in red meat and moderate in dairy, eggs, poultry and fish which will be beneficial for both health and the environment. A systematic review of observational and intervention studies published between 2000 and January 2020 was conducted to assess nutrient intake and status in adult populations consuming plant-based diets (mainly vegetarian and vegan) with that of meat-eaters. Mean intake of nutrients were calculated and benchmarked to dietary reference values. For micronutrient status, mean concentrations of biomarkers were calculated and compared across diet groups. A total of 141 studies were included, mostly from Europe, South/East Asia, and North America. Protein intake was lower in people following plant-based diets compared to meat-eaters, but well within recommended intake levels. While fiber, polyunsaturated fatty acids (PUFA), folate, vitamin C, E and magnesium intake was higher, eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) intake was lower in vegetarians and vegans as compared to meat-eaters. Intake and status of vitamin B12, vitamin D, iron, zinc, iodine, calcium and bone turnover markers were generally lower in plant-based dietary patterns compared to meat-eaters. Vegans had the lowest vitamin B12, calcium and iodine intake, and also lower iodine status and lower bone mineral density. Meat-eaters were at risk of inadequate intakes of fiber, PUFA, α-linolenic acid (ALA), folate, vitamin D, E, calcium and magnesium. There were nutrient inadequacies across all dietary patterns, including vegan, vegetarian and meat-based diets. As plant-based diets are generally better for health and the environment, public health strategies should facilitate the transition to a balanced diet with more diverse nutrient-dense plant foods through consumer education, food fortification and possibly supplementation.     

Haematological studies on pre-menopausal Indian and Caucasian vegetarians compared with Caucasian omnivores

Full blood counts, serum ferritin, vitamin B12 and folate, erythrocyte folate concentrations and nutrient intakes were estimated in twenty-three Indian vegetarian, twenty-two Caucasian omnivores and eighteen Caucasian vegetarian women aged 25-40 years. Energy and copper intakes were lower in the Indian women than in the Caucasians. Intakes of dietary fibre, vitamin C and folate were greater and the proportion of energy derived from fat was lower in the vegetarians than in the omnivores. Vitamin B12 and protein intakes were lower in both vegetarian groups than in the omnivores. Fe intake was similar in all the groups but haem Fe provided one-quarter of the Fe intake of the omnivores. Haemoglobin concentrations were generally inside the normal range in all groups, but were lower in the Indians as were mean corpuscular volume (MCV) and mean corpuscular haemoglobin (MCH). Higher MCV, MCH and lower erythrocyte (RBC) counts were observed in Caucasian vegetarians compared with the Caucasian omnivores. In both groups of vegetarians, concentrations of serum vitamin B12 and ferritin were markedly lower than in the omnivores. RBC folate concentrations were lower in the Indians than in either of the Caucasian groups when subjects taking supplements were excluded. It is concluded that vegetarians need to ensure they have adequate intakes of Fe and vitamin B12.     

Dietary and hormonal interrelationships among vegetarian Seventh-Day Adventists and nonvegetarian men

The relationship between dietary nutrients and plasma testosterone, 5 alpha-dihydrotestosterone, estradiol-17 beta, luteinizing hormone, and prolactin levels was investigated in 12 Seventh-Day Adventist (SDA) vegetarian (SV), 10 SDA nonvegetarian (SNV), and 8 non-SDA nonvegetarian (NV) men. Fasting blood samples and 3-day dietary intake information were obtained from each subject. The SV subjects consumed significantly more crude and dietary fiber than the SNV and NV subjects, respectively. Plasma levels of testosterone and estradiol-17 beta were significantly lower in the SV than in the omnivores. Additionally, the plasma levels of testosterone and estradiol-17 beta of the combined groups (SV, SNV, and NV) revealed a significant negative relationship with their crude and dietary fiber intakes. These subjects hormonal milieu was related to specific dietary constituents, possibly leading to a decreased plasma concentration of androgen and estrogen in vegetarians. Implications include the possible modification of prostate cancer risk through dietary intervention.     

Zinc Status of Vegetarians during Pregnancy: A Systematic Review of Observational Studies and Meta-Analysis of Zinc Intake

Pregnant women are vulnerable to a low zinc status due to the additional zinc demands associated with pregnancy and foetal development. The present systematic review explores the relationship between habitual vegetarian diets and dietary zinc intake/status during pregnancy. The association between vegetarian diets and functional pregnancy outcome also is considered. A literature search was conducted of MEDLINE; PubMed; Embase; the Cochrane Library; Web of Science; and Scopus electronic databases up to September 2014. Six English-language observational studies qualified for inclusion in the systematic review. A meta-analysis was conducted that compared the dietary zinc intake of pregnant vegetarian and non-vegetarian (NV) groups; the zinc intake of vegetarians was found to be lower than that of NV (−1.38 ± 0.35 mg/day; p < 0.001); and the exclusion of low meat eaters from the analysis revealed a greater difference (−1.53 ± 0.44 mg/day; p = 0.001). Neither vegetarian nor NV groups met the recommended dietary allowance (RDA) for zinc. In a qualitative synthesis; no differences were found between groups in serum/plasma zinc or in functional outcomes associated with pregnancy. In conclusion; pregnant vegetarian women have lower zinc intakes than NV control populations and both groups consume lower than recommended amounts. Further information is needed to determine whether physiologic adaptations in zinc metabolism are sufficient to meet maternal and foetal requirements during pregnancy on a low zinc diet.     

Dietary intake among young adolescents in Ontario: associations with vegetarian status and attitude toward health

BACKGROUND: This study aimed to describe the dietary intakes of adolescent vegetarians and omnivores and determine if, and how, attitude toward personal health related to food consumption. METHODS: Among grade 9 students in Ontario, Canada (n = 630), vegetarian status and estimated consumption of foods and food groups were determined by food frequency questionnaire. Personal health was self-categorized as very important (the "health conscious") or somewhat/not important (the "non-health conscious"). RESULTS: The prevalence of vegetarianism was 6.5% (CI = 4.6-8.4%) among females and 1.0% (CI = 0.2-1.8%) among males. Health-conscious omnivores consumed more grain, vegetables and fruit, and milk product than non-health-conscious omnivores (P < 0.05). Health-conscious vegetarians ingested more grain products, vegetables and fruit, and meat and alternatives than non-health-conscious vegetarians (P < 0.05). Among non-health-conscious vegetarians, none consumed two daily servings of meat and alternatives compared to 60.5% of non-health-conscious omnivores (P < 0.001). Among health-conscious vegetarians, milk product consumption was lower than that of health-conscious omnivores (P = 0.015). CONCLUSIONS: Large proportions of both vegetarian and omnivore adolescents consumed suboptimal diets. Health consciousness had value as an indicator of dietary adequacy and may be useful as a rudimentary screen for problematic dietary consumption patterns.