Phytomicronutrients: Overview and Challenges in Establishing Recommended Dietary Allowances and Health Claim Regulations

Phytomicronutrients encompass diverse plant secondary metabolites such as polyphenols, carotenoids (e.g., lycopene, lutein), flavonoids, glucosinolates, and allyl sulfides. This paper reviews their dietary sources, chemical classification into terpenoids, phenolics, and sulfur compounds, and their low bioavailability. It highlights epidemiological and experimental evidence linking higher intakes with reduced risk of diabetes, cardiovascular diseases, and certain cancers. The absence of established RDAs stems from a lack of demonstrated essentiality and the complexity of their metabolic pathways. It also discusses existing EFSA-approved health claims and emerging research on gut microbiota interactions, pointing to promising future applications in human health.