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How Safe are Antioxidant Food Supplements Containing Selenium?
Acta Chimica Slovenica
|September 25, 2013
Summary
Antioxidant supplements often misrepresent selenium content and species. Analysis revealed significant discrepancies between declared and actual selenium levels and forms in tested products, raising health concerns.
Area of Science:
- Nutritional Science
- Analytical Chemistry
- Food Supplement Analysis
Background:
- Antioxidant food supplements commonly contain selenium (Se) and coenzyme Q10.
- Accurate labeling of Se content and species is crucial for consumer safety and product efficacy.
- Previous analyses suggest potential variability in supplement composition.
Purpose of the Study:
- To quantify selenium (Se) content in three antioxidant food supplements.
- To identify and quantify specific selenium species present in the supplements.
- To compare the determined Se content and species against product labels.
Main Methods:
- Sample preparation involved acid digestion.
- Total selenium determination using hydride generation atomic fluorescence spectrometry (HG-AFS).
- Selenium speciation analysis via enzymatic hydrolysis, ion-exchange chromatography, and inductively coupled plasma mass spectrometry (HPLC-ICP-MS).
Main Results:
- One supplement (Product C) contained 69 µg Se/capsule, significantly exceeding its declared 10 µg Se/capsule.
- Product C's declared sodium selenite was not detected; selenocysteine 2 (SeCys2) comprised 55% of total Se.
- Product B showed 60% selenite, and Product A contained 75% selenomethionine (SeMet), with discrepancies noted between declared and detected Se forms.
Conclusions:
- Significant inaccuracies exist in the declared selenium content and species of tested antioxidant supplements.
- The detected selenium species did not always match the declared forms, particularly in Products A and C.
- These discrepancies highlight potential risks for consumers regarding accurate nutrient intake and supplement safety.
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