Micronutrient intake and nutritional status in 16-to-24-year-olds adhering to vegan, lacto-ovo-vegetarian, pescatarian or omnivorous diets in Sweden.

Abstract

The nutritional adequacy of plant-based diets for youth is of public health relevance but is insufficiently studied. This cross-sectional study aims to assess the micronutrient intake and nutritional status in youth adhering to vegan, lacto-ovo-vegetarian, pescatarian or omnivorous diets in Sweden. Healthy 16-to-24-year-olds (n = 60 vegans, n = 59 lacto-ovo-vegetarians, n = 55 pescatarians, n = 61 omnivores) completed a 255-item web-based questionnaire, conducted four non-consecutive 24-hour dietary recalls, provided capillary blood samples and one spot urine sample. Usual micronutrient intakes were estimated by the Multiple Source Method. At the group level, risk of inadequate intake was defined as > 50% with intakes below average requirements. Samples were analysed for haemoglobin (HB), serum transferrin receptor (sTfR), homocysteine (tHcy), methylmalonic acid (MMA), 25-hydroxyvitamin D3 (25-OH-D3), and urinary iodine concentration (UIC). From foods and supplements, all dietary groups demonstrated a risk of inadequate intakes of vitamin D and selenium, additionally vitamin A and calcium in vegans, B 12 in lacto-ovo-vegetarians, and potassium in pescatarians. Median blood marker values of HB, sTfR, tHcy and MMA were within normal ranges across dietary groups. Insufficient 25-OH-D3 concentration (< 50 nmol/L) was observed in vegans, lacto-ovo-vegetarians, and omnivores. A significantly higher proportion of vegans were at risk of vitamin D deficiency (25-OH-D3 < 30 nmol/L) than pescatarians and omnivores. Median UIC (< 100 µg/L) indicated a risk of inadequate iodine intake in vegans, pescatarians, and omnivores. Youth, regardless of dietary practice, need support to ensure adequate micronutrient intakes, particularly for vitamin D and selenium. Further research is required to evaluate iodine nutrition in Swedish youth.