Fruits of luo han guo are intensely sweet, with the purified constituents estimated to be about 150 times sweeter than sucrose. There is potential for use as a noncaloric sweetener. The purified, sweet principle, mogroside V, is approved as a high-intensity sweetening agent in Japan.

Highly sweet cucurbitane glycosides from the fruits of luo han guo, and other plant extracts, were evaluated for sweetness using electrophysiological and behavioral testing in gerbils. Gerbils trained to avoid sucrose identified the extracts as being sweet through avoidance.  Another study in gerbils showed that mogroside V stimulated the gustatory receptors and induced behavioral responses to the compound's sweet taste.