To provide electrochemically bioactive fine particles capable of giving a field abundant in anions to vital tissue when orally ingested.

The electrochemically bioactive fine particles supply negative electric charges to the inside of the vital bodies of animals and plants so as to develop electrochemical bioactivation. The electrochemically bioactive fine particles preferably comprise fine particles of a noble metal, such as gold, platinum and palladium, and more preferably comprise colloidal platinum particles. The colloidal platinum particles each have a size of 2-3 nm as a single particle and are dispersed in such a state that the single particles aggregate to form chain-shaped particles having a size of 4-8 nm. The platinum colloid comprising the colloidal platinum particles forms the field abundant in anions inside the vital bodies and continuously gives electric potential to water molecules absorbed through gastrointestinal membrane. These characteristics are maintained while the platinum colloid is orally ingested, then passed through the large bowel and finally discharged from the fundament. Further, the platinum colloid does not stay inside the vital bodies.