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Improvement of the Selenium Supply in a Vegan Diet by Different Selenium Sources

Human Intervention Study on the Improvement of the Selenium Supply in a Vegan Diet by Different Selenium Sources

Status
Completed
Phases
NA
Study type
Interventional
Source
ClinicalTrials.gov
Registry ID
NCT05814874
Acronym
SelVeg
Enrollment
90
Registered
2023-04-18
Start date
2023-03-20
Completion date
2023-06-05
Last updated
2025-03-21

For informational purposes only — not medical advice. Sourced from public registries and may not reflect the latest updates. Terms

Conditions

Diet, Vegan, Selenium

Brief summary

As vegans are among the individuals with the lowest serum selenium levels, the randomized controlled SelVeg study aims to address the question of whether Brazil nuts could be an adequate source of selenium for diets potentially low in selenium. For this purpose, we will investigate in individuals with a vegan or omnivorous dietary pattern how a daily selenium intervention in the form of a food (here Brazil nut butter) or an over-the-counter selenium supplement affects the selenium status.

Detailed description

The vegan diet is characterized by an exclusion of all animal foods and is associated with positive health effects. However, dietary restriction can lead to inadequate intake of both macro- and micronutrients. Selenium and zinc, among others are critical nutrients in a vegan diet. Brazil nuts represent a particularly selenium-rich plant food. In addition to selenium Brazil nuts have also relevant amounts of other trace elements, including zinc, iron and copper. Therefore, the aim of this study is to evaluate the effect of a daily selenium supplementation in the form of Brazil nut butter in comparison to a selenium supplement. As primary outcome, the serum selenium concentration and other serum biomarkers of the selenium status will be analyzed. Additionally, serum levels of other trace elements such as zinc will be quantified. Dietary questionnaires will provide information on dietary intake of nutrients (focus on dietary fiber, zinc and phytate intake) to identify potential factors influencing selenium bioavailability. The SelVeg study will enroll 90 healthy subjects with either a vegan (defined as exclusion of animal products) or omnivore (defined as weekly consumption of meat and/or sausage) dietary pattern. After categorizing in vegans or omnivores, participants are than randomized in one of the three intervention groups (placebo, Brazil nut or selenium supplement) and will receive 55 µg of additional daily selenium (as Brazil nut butter or tablet) or no additional selenium in case of placebo. The intervention period is 2 weeks.

Interventions

DIETARY_SUPPLEMENTselenium supplement

Selenium supplement containing 55 µg of sodium selenate

DIETARY_SUPPLEMENTBrazil nut

Brazil nut butter; consumption corresponds to a selenium intake of 55 µg/d

OTHERPlacebo

Placebo pill

Sponsors

University of Jena
Lead SponsorOTHER

Study design

Allocation
RANDOMIZED
Intervention model
PARALLEL
Primary purpose
BASIC_SCIENCE
Masking
NONE

Intervention model description

non-blinded randomized controlled trial Parallel group design (2 groups): vegan (exclusion of animal products) vs. omnivore (weekly consumption of meat and/or sausage), stable dietary habit since at least one year, 3 intervention groups (placebo, Brazil nut or selenium supplement)

Eligibility

Sex/Gender
ALL
Age
18 Years to 35 Years
Healthy volunteers
Yes

Inclusion criteria

* Apparently healthy participant * Adherence to one of following eating habit (vegan or omnivore) confirmed by food frequency protocol (5 d), lifestyle and nutrition questionnaires * Stable eating habit for at least 1 year before enrollment

Exclusion criteria

* Diet other than omnivore or vegan * Changing diet during the study period * Baseline serum selenium concentration \> 150 µg/L * Acute or chronic disease (tumor, infection, other), gastrointestinal diseases, chronic renal disease, diseases of the parathyroids, diseases necessitating regular phlebotomies * Nut allergy * Pregnancy or lactation

Design outcomes

Primary

MeasureTime frameDescription
Selenium statusbaseline and after 2 weeksChanges in serum selenium concentration \[µg/L\] and selenoprotein-based biomarkers (SELENOP and GPX \[U/L\]) after intervention

Secondary

MeasureTime frameDescription
Trace element serum concentrationsbaseline and after 2 weeksChange in serum concentration of trace elements (zinc, copper, manganese, iron, potassium and calcium \[µg/L\]) after intervention
Anthropometric databaseline and after 2 weeksbody mass index \[kg/m2\]
Mean macro- and micronutrient intake over 5 daysbaseline
Dietary zinc and phytate intake6 monthsZinc and Phytate Diet Score (= frequency index \* quantity index \* zinc or phytate content \[mg\])

Countries

Germany

Outcome results

None listed

Source: ClinicalTrials.gov · Data processed: Feb 6, 2026