Bee Pollen as a Dietary Mineral Source: In Vitro Bioaccessibility and Health Risk Evaluation

Pollen, the male gametophyte of flowering plants, is collected by honeybees as a primary source of protein and converted into bee pollen through the enzymatic activity of digestive secretions. The nutrients in bee pollen are available in amounts well beyond those of proteins, comprising macronutrients such as carbohydrates, lipids and dietary fiber, as well as micronutrients such as minerals, vitamins, organic acids, and phenolic compounds. This study aimed to determine the macro and trace mineral content of bee pollen from different botanical and geographical origins, and to assess their bioaccessibility through simulated in vitro digestion, their dietary contribution, and potential health risks. Seven bee pollen samples were investigated, three with a monofloral origin of above 80%, from Nigella spp., Helianthus annuus and Castanea sativa, and four with a multifloral origin. Mineral composition revealed potassium as the most abundant element, while iron, manganese, and copper were found at trace levels. Castanea sativa pollen had the highest overall mineral content, whereas Nigella spp. showed the lowest values for calcium, magnesium, and copper. The bioaccessibility of bee pollen was highest during the gastric phase for most minerals except copper, where most of the samples peaked in the intestinal phase. Overall, mineral bioaccessibility after simulated digestion followed the order K > Mg > Cu > Ca > Mn > Fe > Zn. While for manganese, the consumption of bee pollen showed the highest contribution to recommended dietary intake (16% for women and 12% for men), calcium had the lowest, with less than 1% of the RDA at a consumption level of 40 g/day. Health risk assessment confirmed that consuming 40 g/day of bee pollen poses no risk because the target hazard quotient and hazard index are below the risk threshold of 1.0.