  The Higgs-Dilaton cosmological model is able to describe simultaneously an
inflationary expansion in the early Universe and a dark energy dominated stage
responsible for the present day acceleration. It also leads to a non-trivial
relation between the spectral tilt of scalar perturbations n_s and the dark
energy equation of state \omega. We study the self-consistency of this model
from an effective field theory point of view. Taking into account the influence
of the dynamical background fields, we determine the effective cut-off of the
theory, which turns out to be parametrically larger than all the relevant
energy scales from inflation to the present epoch. We finally formulate the set
of assumptions needed to estimate the amplitude of the quantum corrections in a
systematic way and show that the connection between n_s and \omega remains
unaltered if these assumptions are satisfied.
