Quality and safety assessment of food supplements containing caffeine and iodine

Caffeine-containing food supplements are often used as weight loss or memory enhancement support, which increases the potential risk for overdosing the compound. Whereas the presence of iodine-containing seaweed fucus in such products may result in thyroid disorders, when permanently overdosed. The study aimed to assess the content of caffeine and iodine in food supplements. Caffeine amount in tablets and capsules ranged from 91.8 to 138.9% of the declared content, and 2.6 +/- 0.3 to 21.8 +/- 2.8 mg/portion for the herbal blends with undeclared caffeine content. Iodine content ranged from 10.6 +/- 0.4 to 52.5 +/- 3.7 mu g/portion of the products. Our results, although preliminary, suggest questionable usefulness of the tested preparations as weight loss support. Likewise, a simultaneous consumption of the recommended amounts with caffeine from other sources (e.g. coffee, tea, energy drinks, etc.), is unlikely to cause adverse effects.