A microalgae docosahexaenoic acid supplement does not modify the influence of sex and diet on iron status in Spanish vegetarians or omnivores: A randomized placebo-controlled crossover study

OBJECTIVE

Plant-based diets are accepted as healthy, provided that are well-planned and include supplements. In this context, iron deficiency is a threat, and data from Spanish vegetarians are scarce. The aim of this study was to determine if a microalgae ω-3 supplement rich in docosahexaenoic acid (DHA) affected iron status in this population.

METHODS

Iron biomarkers and nutrient intake (72-h dietary records) were analyzed in 204 usual consumers of lacto-ovo vegetarian (LOV), vegan (VEG), or omnivorous (OMN) diets. A randomized double-blind, placebo-controlled crossover trial was performed in a subgroup (n = 98) to test if a microalgae DHA supplement (250 mg/d for 5 wk) changed iron status.

RESULTS

Iron intake was higher in vegetarians than omnivores (P= 0.002), fiber intake was highest in vegans followed by lacto-ovo vegetarians and omnivores, whereas calcium intake was lower in vegans than both lacto-ovo vegetarians and omnivores (all P < 0.001). Women, regardless of diet type, showed lower iron status than men. Erythrocytes, hemoglobin, hematocrit, and serum ferritin were lower in lacto-ovo vegetarians and vegans than omnivores. The prevalence of iron deficiency anemia was low (<10%), but iron depletion (ferritin <15 ng/mL) was higher in lacto-ovo vegetarians than omnivores (P = 0.003). Iron biomarkers were similar in lacto-ovo vegetarians and vegans. The DHA supplementation did not change iron status compared with placebo.

CONCLUSIONS

Spanish vegetarians had lower iron status than omnivores. Consumption of eggs and dairy products increased the risk for iron deficiency, but a microalgae DHA supplement had no effect. Dietary strategies to increase iron bioavailability in vegetarians, particularly in lacto-ovo vegetarians and women, are recommended.

Gender-specific influence of health behaviors on academic performance in Spanish adolescents: the AFINOS study

INTRODUCTION

New paradigms based on the multifactorial etiology of chronic diseases and behavioral outcomes suggest that a combination of health behaviors may have more impact on the outcome of interest than any single factor.

OBJECTIVE

To examine the independent and combined influence of four health behaviors on school performance in Spanish adolescents.

METHODS

A total of 1825 Spanish adolescents reported their grades in Language and Literature (LL) and Math. Body mass index, family structure and school-related factors (attitude to school, need to repeat > 1-yr and absenteeism) were self-reported. Adolescents were dichotomized as healthy or unhealthy based on meeting or not meeting lifestyle recommendations on physical activity, TV viewing, sleep and fruit intake. Each adolescent was also scored according to the number of healthy recommendations fulfilled.

RESULTS

In boys, there were no associations between health behaviors and academic performance. Good academic performance in girls was associated with physical activity (P < 0.05) or fruit consumption (P < 0.05). Moreover, girls who scored 3-4 health behaviors showed higher odds of passing LL (OR = 3.18, P < 0.001), Math (OR = 1.75, P = 0.028) or LL+Math (OR = 2.32, P = 0.001) compared with those with 0-1 health behaviors. All the analyses were adjusted by weight status, family context and different school-related factors.

CONCLUSIONS

A combination of health behaviors may have a positive influence on academic performance in adolescent girls.

Design of the nutritional therapy for overweight and obese Spanish adolescents conducted by registered dieticians: the EVASYON study

BACKGROUND

Dietary treatment for obese adolescents should aim to ensure adequate growth and development, by reducing excessive fat mass accumulation, avoiding loss of lean body mass, improving well-being and self-esteem and preventing cyclical weight regain. The aim of this article is to describe the dietary intervention design and the methods used to evaluate nutritional knowledge and behavior in the EVASYON study (Development, implementation and evaluation of the efficacy of a therapeutic programme for overweight/obese adolescents).

METHODS/DESIGN

EVASYON is a multi-centre study conducted in 5 Spanish hospital settings (Granada, Madrid, Pamplona, Santander and Zaragoza), where 204 overweight/obese Spanish adolescents were treated in groups of 9 to 11 subjects over 20 visits. The study was implemented in two stages: an intensive, calorie-restricted period for the first 9 weeks, and an extensive body-weight follow-up period for the last 11 months. A moderate energy intake restriction was applied in the intensive period according to the degree of obesity, on the basis of a balanced diet supplying 50-55% of daily energy as carbohydrates; 30-35% as fats and 10-15% as proteins. In the intensive period, adolescents were prescribed both a fixed full-day meal plan for the first three weeks and a full day meal plan with different food-choices for 6 weeks. Later, adolescents received a flexible meal plan based on food exchanges for the follow-up period until the end of the trial. Data on food intake, dietary and meal-related habits and behavior were collected by means of dietary questionnaires. To analyse nutritional knowledge, adolescents were examined regarding nutrient concepts and food adoitems for a healthy diet with the appropriate tools. Participants were given nutritional information with complementary teaching material, which was available on the EVASYON website (www.estudioevasyon.com).

DISCUSSION

The dietary intervention of the EVASYON programme with a moderate calorie restriction for a limited period of time could be a good strategy in treating overweight and obese adolescents and that will be tested further. Moreover, combining fixed plan with free-choice menus may help adolescents and their families to make right decisions for every day meals.