  The effects of energy loss in cold nuclear matter on J/psi suppression in p-A
collisions are studied. A simple model based on first principles and depending
on a single free parameter is able to reproduce J/psi suppression data at large
xF and at various center-of-mass energies. These results strongly support
energy loss as a dominant effect in quarkonium suppression. They also give some
hint on its hadroproduction mechanism suggesting color neutralization to happen
on long time-scales. Predictions for J/psi and Upsilon suppression in p-Pb
collisions at the LHC are made.
