If you Bite Off More Than You Can Chew you’ve taken on more than you can manage, perhaps greedily. The phrase is of American origin, traceable to the 1800s and the popular habit of chewing tobacco. This tobacco was produced in lengths and it was common to offer others a “bite” (in the same way as its common these days to offer somebody a cigarette from a packet). Greedy people would take too large a bite to chew properly, intending to try to break it down and save some for later, without their benefactor realising it. Of course people became wise to this, hence the warning “don't bite off more than you can chew”.