Since the requirement in the US for the use of bear canisters (plastic cylinders that bears cannot open) for food storage the problem has gotten a lot better. Bears used to be more aggressive once they learned that people have food. Now in general they have learned that the food cannot be accessed and tend to stay away; though some have learned that if you scare the people when the canister is open they can get the food out.

@Cerium I'm not aware of any such requirement per se, mostly just that it's good advice. We used to tie our food up but you have to pick the right tree or the bear will simply climb up the tree or pull the tree over to bring the food within reach.

The regulations are not national, but enforced by individual park services. As far as I'm aware all national parks with bears require proper food storage. Many states have regulations as well. A quick search shows that parks in New York with bears require their use during the summer.