Ubushakashatsi bwerekana ko hafi igice ca gatatu c’abantu bose bo kw’isi banywa ikawa. Abantu bamwe bayinywa kubera ko imota neza kandi iryoshe, abandi nabo bakayikunda kubera caffeine iri mw’ikawa ituma bakanguka. Yamara abo bantu bose nti bazi aho iyo kawa yavuye n’ukungene itunganywa.
Bimwe mu bivugwa k’ukungene ikawa yatowe muri kahise ka kera, bishimikira ku muntu yitwa Kaldi. Kaldi yari umwungere, yararagira impene ziwe mu misozi yo muri Ethiopia, mu karere karimwo ibiti vy’ikawa vyari bimaze ibinjana bitari bike. Uwo Kaldi yabonye ko mu gihe impene ziwe zihejeje kurya utwamwa dutoyi zakura kur’ivyo biti vy’ikawa, zaca zikerebuka cane.
Kaldi yabariye umugwi w’abakozi b’imana ivyo yabonye, abo bakozi nabo baca bahingura ikinyobwa bakoresheje utwo twamwa. Mu nyuma babonye ko mu gihe bahejeje kunywa ico kinyobwa, baca bamara igihe kirekire bakanuye, bikabaha umwanya uhagije wo gusenga. Uko niko inkuru yerekeye amamuko y’ikawa yatanguye ihava ikwira isi yose.