Alda Pereira Da Silva

Dr. Alda Pereira Da Silva

Faculdade de Medicina, Universidade de Lisboa, Lisbon, Portugal

Research Focus & Metrics

Academic Career Length

4Years (2023-Present)

(Calculated once Scilit publication data is synced: current year − year of first publication + 1)

Representative Publications

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10 May 2024 in Nutrients
Verified
Journal Article
Open access
PDF file
SFSávio Teixeira Fernandes
Sávio Teixeira Fernandes
LOLeandro Oliveira
Leandro Oliveira
Alda Pereira Da SilvaAlda Pereira Da Silva
Alda Pereira Da Silva
Maria do Céu Gonçalves da CostaMaria do Céu Gonçalves da Costa
Maria do Céu Gonçalves da Costa
ARAntónio Raposo
António Raposo
Bruno MagalhãesBruno Magalhães
Bruno Magalhães
With a significant portion of the population adopting veganism and conflicting views among nutrition professionals regarding the necessity of vitamin B12 supplementation, this review aims to explore existing studies evaluating interventions through food supplementation. It focuses on the impact of vitamin B12 deficiency across different demographics. The present study seeks to understand how research has addressed the relationship between the rise in veganism and vitamin B12 deficiency over the past decade. A scoping review was conducted following the PRISMA flow diagram. Studies from 2010 to 2023 were identified using Boolean operators and key terms in electronic databases such as PubMed/MEDLINE, Web of Science, and EBSCO (Library, Information Science & Technology Abstracts, and Academic Search Complete). Out of 217 articles identified, 70 studies were included. The topical analysis categorized the studies into three groups: those associating vitamin B12 deficiency with diseases (n = 14), those analyzing the dietary habits of vegetarian individuals (vegan or not) without a specific focus on vitamin B12 (n = 49), and those addressing food guides and nutrition institution positions (n = 7). The authors concluded that vitamin B12 deficiency is prevalent among vegans due to limited consumption of animal products. For vegetarians, supplementation is an efficient means of treating and preventing deficiency; a daily dose of 50 to 100 micrograms is advised. There are still significant gaps in the research, nevertheless, such as the absence of randomized controlled trials evaluating various forms or dosages of vitamin B12 among vegetarians and the requirement for more information and awareness of the vitamin’s significance in vegan diets.

14 February 2024
Verified
Book Chapter
Open access
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Alda Pereira Da SilvaAlda Pereira Da Silva
Alda Pereira Da Silva
MCMaria Do Céu Costa
Maria Do Céu Costa
MBManuel Pires Bicho
Manuel Pires Bicho
The use of plants for nutritional and therapeutic purposes has been constant over the centuries. The variability of enzymatic activity between individuals and populations in an attempt to adapt has been a conditioning mechanism, reflected in the incidence and prevalence of certain diseases, possible adverse effects of plant-derived nutrients and their interaction with medications, in addition to interference in natural selection and consequent geographical distribution of specific genetic polymorphisms in harmony with indigenous medicinal plants. The metabolizer type may influence the anticancer protective effect of certain plant-derived constituents, with interindividual variability to be considered. This chapter will deepen and develop the role of using plants in different geographic areas and populations over the centuries in producing the genetic variability of the metabolism of plant constituents in the context of environmental adaptation and ecogenetics. Possible therapeutic/adverse effects due to this variability will be discussed.

6 May 2023 in Nutrients
Verified
Journal Article
Open access
PDF file
MCMarta Mendes Costa
Marta Mendes Costa
Alda Pereira Da SilvaAlda Pereira Da Silva
Alda Pereira Da Silva
ASAna Carolina Santos
Ana Carolina Santos
JFjoana ferreira
joana ferreira
MMMário Rui Mascarenhas
Mário Rui Mascarenhas
ANA Paula BARBOSAANA Paula BARBOSA
ANA Paula BARBOSA
The gene TAS2R38 single nucleotide polymorphisms (SNPs-P49A, A262V and V296I) can condition bitter tasting by PAV (proline–alanine–valine) and non-bitter-tasting by AVI (alanine–valine–isoleucine) homozygosity. We evaluated this polymorphisms association with thyroid function, metabolism and anthropometry parameters determined by: Endpoint analysis (SNPs); DXA (fat mass-%, total fat mass—kg, lean mass—kg); Standard methods (lipid metabolism parameters, HbA1c-%, glycemia—mg/dL, insulinemia—µIU/mL, HOMA-IR, uricemia—mg/dL, calcemia—mg/dL and BMI—kg/m2); ELISA (leptinemia—ng/mL); Spectrophotometry (Angiotensin Converting Enzyme activity—UI/L). Statistics: SPSS program; OR [IC95%]; p < 0.05. Sample: 114 hypothyroid, 49 hyperthyroid, and 179 controls. An association between A262V-valine–valine and hypothyroidism/hyperthyroidism was verified (OR = 2.841; IC95% [1.726–4.676]), p < 0.001/OR = 8.915; IC95% [4.286–18.543]), p < 0.001). Protector effect from thyroid dysfunction: A262V-alanine–valine (OR = 0.467; IC95% [0.289–0.757], p = 0.002/OR = 0.132; IC95% [0.056–0.309], p < 0.001) and PAV (OR = 0.456; IC95% [0.282–0.737], p = 0.001/OR = 0.101; IC95% [0.041–0.250], p < 0.001). Higher parameter values associated with genotypes were: fat-mass-% (V296I-valine–isoleucine), lean-mass (P49A-proline–proline; PVI), leptin (AVI), HbA1c (A262V-alanine–valine) and lower values in lean-Mass (AVI; PVV), leptin (A262V-alanine–alanine), HbA1c (PVV), uricemia (V296I-valine–isoleucine), glycemia (A262V-alanine–alanine; AAV) and plasma triglycerides (PVV). In conclusion, TAS2R38 influences thyroid function, body composition and metabolism. Bitter taste perception (PAV) and the genotype A262V-alanine–valine can protect from thyroid dysfunction. AVV, PVV and genotype A262V-valine–valine may confer higher predisposition for thyroid dysfunction, particularly PVV for hyperthyroidism.

30 June 2025 in Life
Verified
Journal Article
Open access
PDF file
Rosa PerestreloRosa Perestrelo
Rosa Perestrelo
MLMaria da Graça Lopes
Maria da Graça Lopes
Alda Pereira Da SilvaAlda Pereira Da Silva
Alda Pereira Da Silva
Maria do Céu Gonçalves da CostaMaria do Céu Gonçalves da Costa
Maria do Céu Gonçalves da Costa
JCJosé S. Câmara
José S. Câmara
The garden Nasturtium (Tropaeolum majus L.) is increasingly consumed worldwide due to its culinary appeal and perceived health benefits. However, the chemical markers underlying its functional properties remain insufficiently characterized. Building on evidence from a recent human pilot study confirming both high acceptability and dietary safety, we conducted a comprehensive volatilomic and phytochemical analysis of T. majus flowers and their juice. Headspace solid-phase microextraction coupled with gas chromatography–mass spectrometry (HS-SPME/GC-MS) was employed to establish the volatilomic fingerprint of floral tissues and juice. Our analysis revealed a striking dominance of benzyl isothiocyanate and benzonitrile, which together accounted for 88% of the total volatile organic metabolites (VOMs) in the juice, 67% and 21%, respectively. In the floral tissues, benzyl isothiocyanate was even more prevalent, representing 95% of the total volatile profile. Complementary in vitro assays confirmed a substantial total phenolic content and strong antioxidant activity in the flowers. These findings provide a robust chemical rationale for the potential health-promoting attributes of T. majus, while identifying key volatilomic markers that could support future functional and safety claims. In parallel, a benefit–risk assessment framework is discussed in accordance with the European Food Safety Authority (EFSA) guidelines for the Qualified Presumption of Safety (QPS) of edible flowers. Given that both benzyl isothiocyanate and benzonitrile are classified as Cramer Class III substances, a conservative intake threshold of 1.5 μg/kg body weight per day is proposed. To enable quantitative exposure modeling and support the derivation of a tolerable daily intake (TDI), future studies should integrate organic solvent-based extraction methodologies to estimate the total volatile load per gram of floral biomass. This would align risk–benefit assessments with the EFSA’s evolving framework for novel foods and functional ingredients.