There is no scientific proof of this, that I know of. But I have heard taht the salinity has a small part here, higher salinity seems to help better, and sinc3e we have raised an kept ours up about 1.025, then we seem to have lost almost none and this is in several months now. After seeing this, we had set up a tank at work and done the same and have only lost 1 since March(or was it april).
Another thing, we also get TROCHUS snails, which can upright themselves and eat mroe than turbos. But are harder to find and a little more expensive. YOu could try some of them, if you have no other luck with turbos.
Thery are easy to spot, they are black bodied instead of white, but most lfs's dont know and may try to sell them either way(trochusas turbos and vice/versa).