Cobalt (Co), copper (Cu), manganese (Mn), molybdenum (Mo), and zinc (Zn) are essential trace elements (ETEs) and important cofactors for intermediary metabolism or redox balance. These ETEs are crucial during pregnancy, their role on specific pregnancy outcomes is largely unknown. This prospective study (#NCT04010708) aimed to assess urinary levels of these ETEs in pregnancy and to evaluate their association with pregnancy outcomes. First trimester pregnant women of Porto and Lisbon provided a random spot urine sample, and sociodemographic and lifestyle data. Clinical data were obtained from clinical records. Urinary ETEs were quantified by inductively coupled plasma mass spectrometry (ICP-MS). A total of 635 mother:child pairs were included. Having urinary Zn levels above the 50th percentile (P50) was an independent risk factor for pre-eclampsia (PE) (aOR [95% CI]: 5.350 [1.044–27.423], p = 0.044). Urinary Zn levels above the P50 decreased the risk of small for gestational age (SGA) birth head circumference (aOR [95% CI]: 0.315 [0.113–0.883], p = 0.028), but it increased the risk SGA length (aOR [95% CI]: 2.531 [1.057–6.062], p = 0.037). This study may provide valuable information for public health policies related to prenatal nutrition, while informing future efforts to de-fine urinary reference intervals for ETEs in pregnant women.

Objectives: This study aimed to compare the anthropometry and body composition of vegetarian and omnivorous adults living in Portugal, while exploring nutritional and health parameters underlying observed differences. Methods: 425 omnivorous (OMNI), lacto-ovo-vegetarian (LOV), or vegan (VEG) healthy adults were recruited. Anthropometry was measured, and bioelectrical impedance analysis was performed. Participants answered food frequency, sociodemographic, and lifestyle questionnaires. Serum iron, ferritin, and CRP were quantified by spectrophotometry, and serum B12 vitamin and homocysteine were quantified by chemiluminescent microparticle immunoassay. Results: Total protein intake significantly decreased with increasing strictness of vegetarian habits (median (P25; P75) in g/day: 98.6 (79.5; 123.1), 90.4 (65.9; 121.0), and 87.6 (59.8; 118.5) for OMNI, LOV and VEG, respectively; p = 0.020), and carbohydrate intake was the highest in LOV (median (P25; P75) in g/day: 231.5 (178.4; 287.9), 283.9 (227.3; 342.6), and 263.0 (222.0; 348.3) for OMNI, LOV and VEG, respectively; p = 0.001). VEG were the main users of B12 vitamin (93% in VEG vs. 17% in OMNI and 59% in LOV, p = 0.001), and LOV were the main users of iron supplements (29% in LOV vs. 14% in OMNI and 13% in VEG, p = 0.042), respectively. Blood levels of B12 vitamin correlated negatively with blood homocysteine (r_s = −0.386, p < 0.001) and positively with % muscle mass (r_s = 0.136, p = 0.005). Participants using iron supplements presented higher C-reactive protein (CRP) (p = 0.014) and they had lower % MM (p = 0.003). Finally, when compared to being OMNI, being LOV independently associated with: (a) having +4.8% (p = 0.002) of fat mass, which could be due to higher carbohydrate intake, and (b) having −2.2% (p = 0.043) of muscle mass. Our data suggest that the association between diet and muscle mass could be attenuated in VEG due to B12 supplementation and/or aggravated in LOV due to iron supplementation-associated inflammation.