Wikipedia has a well annotated review of the literature.

From a health standpoint, it's only the time shifts that are problematic. I'd be happy with "permanent" DST like some countries have (where clocks are set to read 1 PM at astronomical noon year round).

From an energy standpoint, there may have been clear savings when the practice was initiated during World War I, when the main use of electricity was household lighting. Nowadays, the evidence is mixed at best.