Selenium bioaccessibility and bioavailability in Se-enriched food supplements

Area of Science:

• Nutritional Biochemistry
• Food Science
• Human Health

Background:

• European populations often have suboptimal selenium (Se) intake, below recommended levels for antioxidant selenoprotein function.
• Selenium-enriched food supplements (FS) are commonly used to increase body selenium levels.
• Key Se-rich FS types in Belgium include Se-enriched yeast, selenate-based, and selenite-based supplements.

Purpose of the Study:

• To assess the bioaccessibility and bioavailability of selenium from different types of Se-enriched food supplements.
• To investigate how selenium speciation influences the effectiveness of FS in improving human selenium status.

Main Methods:

• In vitro digestion and intestinal absorption models were employed.
• Analysis of bioaccessible and bioavailable selenium fractions from three distinct FS categories (Se-yeast, selenate, selenite).

Main Results:

• Significant differences in selenium bioaccessibility and bioavailability were observed among the tested FS.
• Overall selenium bioavailability was low, with a maximum of 14% of the initial content.
• Selenate-based FS yielded the highest bioavailable selenium fraction, followed by Se-yeast, while selenite-based FS showed minimal selenium availability.

Conclusions:

• Selenium speciation significantly impacts the bioavailability of selenium from food supplements.
• Selenite-based supplements demonstrate poor selenium bioavailability, contrary to expectations for Se-yeast, which showed moderate bioavailability.