Screening of Nutraceuticals and Functional Foods

Introduction & the evaluation problem

• Definitions — A functional food provides a health benefit beyond basic nutrition (beyond supplying energy and essential nutrients); a nutraceutical is a purified or concentrated bioactive presented in a dosage form for a physiological/health benefit. The discriminating axis between a nutraceutical, a health supplement and a drug is dosage form and claim, not chemistry.
• FOSHU & FUFOSE — Japan's MHLW gave the first formal regulatory definition — FOSHU (Food for Specified Health Use, 1991); Europe's FUFOSE (1999) defined functional foods as satisfactorily demonstrated to beneficially affect one or more target functions beyond adequate nutrition, and crucially insisted they must remain foods ('not pills or capsules'), effective at amounts normally eaten.
• Scoping divergence — A key evaluation fault-line: FOSHU permits capsule/tablet dosage forms whereas FUFOSE explicitly excludes them — the same product may be a functional food in one jurisdiction and a supplement/drug in another, so the evaluation dossier is jurisdiction-shaped.
• The core evaluation problem — Unlike a single-molecule drug, the test article may be a whole food, a fortified food or a purified isolate — often a multi-component matrix of increasing complexity. The screening/evaluation strategy is therefore matrix-dependent, not one-size-fits-all.
• Screening register — Because a functional food should not have a highly potent pharmacological action (that would move it into the drug domain), screening emphasises modest, dietarily-achievable effects demonstrated at realistic intakes, coupled with rigorous safety benchmarking against endogenous mediators and drugs of the same mechanism.