Nutritional status of vegetarian and omnivorous adolescent girls

Calcium intake in vegan and vegetarian diets: A systematic review and Meta-analysis

In recent years, plant-based diets have experienced increasing popularity. However, plant-based diets may not always ensure an adequate supply of micronutrients, in particular calcium. We performed a systematic review and meta-analysis of calcium intake in vegan and vegetarian diets as compared to omnivorous diets. We searched PubMed and Web of Science and identified 2,009 potentially relevant articles. Mean calcium intake values were pooled and standardized mean differences (SMD) and 95% confidence intervals (CI) were computed.We analyzed 74 studies, including 7,356 vegan, 51,940 vegetarian, and 107,581 omnivorous participants. Of these, dietary calcium intake was examined in 23 studies of vegans, 60 studies of vegetarians and 74 studies of omnivores. Vegans showed a substantially lower calcium intake than vegetarians (SMD = -0.57; 95%CI = -0.83 to -0.32; p = <0.0001) and omnivores (SMD = -0.70; 95%CI = -0.95 to -0.59; p < 0.0001), whereas no statistically significant difference in calcium intake was noted between vegetarians and omnivores (SMD = 0.07; 95%CI = -0.04 to 0.19; p = 0.1976). In conclusion, vegans show a lower calcium intake than vegetarians and omnivores. This finding emphasizes the need for vegans to monitor their calcium status.

A Sample of Female Adolescent Self-Identified Vegetarians in New Zealand Consume Less Protein and Saturated Fat, but More Fiber than Their Omnivorous Peers

This study aimed to describe the intake and food sources of macronutrients in vegetarian and non-vegetarian adolescent females. Cross-sectional data was collected between February and September 2019. Adolescent females, aged 15 to 18 years old, were recruited throughout New Zealand. Intakes were assessed via two 24-h diet recalls, adjusted to represent usual intake using the multiple source method. Of the 254 participants, 38 self-identified as vegetarian. Vegetarians had similar carbohydrate and fat intakes compared to non-vegetarians; however, their protein intakes were 2.1% kJ lower (95% confidence interval (CI) −3.0 to −1.1%). Vegetarians also consumed 1.1% kJ less saturated fat (95% CI –2.1 to −0.1%), 1.3% kJ (95% CI 0.7 to 1.9) more polyunsaturated fat, and 5 g/day (95% CI 1.8 to 8.0) more fiber than non-vegetarians. When consumed, bread-based dishes and discretionary foods were the highest sources of energy, fat, and carbohydrate in both vegetarians and non-vegetarians. This suggests that some adolescents, including vegetarians, were obtaining high amounts of fat and carbohydrate from food groups associated with poorer dietary quality. We recommend further research to assess how the changing food environment is influencing vegetarian eating patterns and their associations with health outcomes in the wider population.

Underweight and Associated Factors Among Teenage Adolescent Girls in Resource-poor Settings: A Cross-sectional Study

Background and Purpose

Understanding the undernutrition status of teenage adolescent girls living in urban slums and its associated factors is meaningful to formulate customized health strategies. This study aimed to determine the prevalence of being underweight and associated factors among teenage adolescent girls in urban slums.

Materials and Methods

In this cross-sectional study, we enrolled a total of 418 teenage adolescent girls from five of 210 urban slums of Varanasi district, Uttar Pradesh, India employing two-stage probability sampling for the selection of households and subjects, between September 2016 and July 2017. The study of underwight subjects was assessed with BMI for age using standard criteria. Factors associated with being underweight were determined by multivariable logistic regression analysis.

Results

Of 418 study subjects, 49.76% (208/418) were underweight. Results revealed that sociodemographic factors such as teenage adolescent girls who were from SC/ST (schedule caste/schedule tribe) caste/ethnicity (adjusted odds ratio (AOR)=2.02, 95%CI: 1.00–4.23), subjects whose father’s education level was primary or lower (AOR=1.87, 95%CI: 1.12–3.11), and number of people in the family >4 (AOR=2.18, 95%CI: 1.18–4.03) were associated with being underweight. Likewise, dietary behavior-related factors such as vegetarian (AOR=2.21, 95%CI: 1.25–3.92), and <3 meals per day (AOR=2.36, 95%CI: 1.40–3.98) than their counterparts were associated with being underweight. In addition, teenage adolescent girls from food-insecure households (AOR=3.33, 95%CI: 2.01–5.51) were more likely to be underweight than those from food-secure households.

Conclusion

The higher burden of underweight among teenage adolescent girls in Indian urban slums needs to be addressed through specific public health interventions such as by improving education, providing education regarding dietary behavior, and having access to sufficient, safe, and nutritious foods.

The effect of vegetarian diets on iron status in adults: A systematic review and meta-analysis

BACKGROUND

Vegetarian diets exclude meat, seafood, and products containing these foods. Although the vegetarian lifestyle could lead to a better health status in adults, it may also bear risks for certain nutritional deficiencies. Cross-sectional studies and narrative reviews have shown that the iron status of vegetarians is compromised by the absence of highly bioavailable haem-iron in meatless diets and the inhibiting effect of certain components present in plant foods on non-haem iron bioavailability.

METHODS

The databases Pubmed, Scopus, Embase, and Cochrane CentralRegister of Controlled Trials were searched for studies comparing serum ferritin, as the major laboratory parameter for iron status of adult vegetarians with non-vegetarian control groups. A qualitative review was conducted as well as an inverse-variance random-effects meta-analysis to pool available data. In addition the effect of vegetarian diets according to gender was investigated with a subgroup analysis. The results were validated using a sensitivity analysis.

RESULTS

A total of 27 cross-sectional studies and three interventional studies were selected for the systematic review. The meta-analysis which combined data of 24 cross-sectional studies showed that adult vegetarians have significantly lower serum ferritin levels than their non-vegetarian controls (-29.71 µg/L, 95% CI [-39.69, -19.73], p < 0.01). Inclusion of semi-vegetarian diets did not change the results considerably (-23.27 µg/L, 95% CI [-29.77, -16.76], p < 0.01). The effects were more pronounced in men (-61.88 µg/L, 95% CI [-85.59, -38.17], p < 0.01) than in both premenopausal women (-17.70 μg/L, 95% CI [-29.80, -5.60], p < 0.01) and all women (-13.50 μg/L, 95% CI [-22.96, -4.04], p < 0.01), respectively.

CONCLUSIONS

In conclusion our results showed that vegetarians are more likely to have lower iron stores compared with non-vegetarians. However, since high iron stores are also a risk factor for certain non-communicable diseases, such as type 2 diabetes, it is recommended that not only vegetarians but also non-vegetarians should regularly control their iron status and improve their diet regarding the content and bioavailability of iron by consuming more plants and less meat.

Micronutrient supplement use and diet quality in university students

Many national and international public health organisations recommend achieving nutrient adequacy through consumption of a wide variety of nutritious foods. Despite this, dietary supplement sales continue to increase. Understanding the characteristics of micronutrient supplement users and the relationship with diet quality can help develop effective public health interventions to reduce unnecessary consumption of vitamin and mineral supplements. Participants (n = 1306) were a convenience sample of students studying first year food and nutrition. Data was collected via a Food and Diet Questionnaire (FDQ) and a Food Frequency Questionnaire (FFQ). Supplement users were defined as participants who indicated consuming any listed supplement as frequently as once a month or more. Diet quality was assessed using a Dietary Guideline Index (DGI) score. Prevalence of supplement use was high in this study population with 56% of participants reporting supplement use; the most popular supplements consumed were multivitamins (28%) and vitamin C (28%). A higher DGI score was significantly associated with an increased likelihood of supplement use (mean: 105 ± 18 vs. 109 ± 17, p = 0.001). Micronutrient supplement use was associated with a higher DGI score, suggesting that supplements are more likely to be used by those who are less likely to require them.