There is no conclusive evidence that drinking coffee causes cancer, the World Health Organization's cancer agency said on Wednesday in a reverse of its previous warning, but it also said all "very hot" drinks are probably carcinogenic.

The International Agency for Research on Cancer (IARC) had previously rated coffee as "possibly carcinogenic" but has changed its mind.

It now says its latest review found "no conclusive evidence for a carcinogenic effect" of coffee drinking and pointed to some studies showing coffee may actually reduce the risk of developing certain types of cancer.