have too much of a good thing

have too much of a good thing

Prov. To hurt yourself by overindulging in something good. I've gained five pounds from all the holiday dinners I've eaten this month. I think I had too much of a good thing. Alan: We're having such a good time at this resort, why don't we stay another week? Jane: I think we'd get bored with it if we stayed that long. You can have too much of a good thing, you know.

See also: good, have, much, thing