  Isospin-violating dark matter (IVDM) has been proposed as a viable scenario
to reconcile conflicting positive and null results from direct detection dark
matter experiments. We show that the lowest-order dark matter-nucleus
scattering rate can receive large and nucleus-dependent corrections at
next-to-leading order (NLO) in the chiral expansion. The size of these
corrections depends on the specific couplings of dark matter to quark flavors
and gluons. In general the full NLO dark-matter-nucleus cross-section is not
adequately described by just the zero-energy proton and neutron couplings.
These statements are concretely illustrated in a scenario where the dark matter
couples to quarks through scalar operators. We find the canonical IVDM scenario
can reconcile the null XENON and LUX results and the recent CDMS-Si findings
provided its couplings to second and third generation quarks either lie on a
special line or are suppressed. Equally good fits with new values of the
neutron-to-proton coupling ratio are found in the presence of nonzero heavy
quark couplings. CDMS-Si remains in tension with LUX and XENON10/100 but is not
excluded.

High Energy Physics - Phenomenology;High Energy Astrophysical Phenomena;High Energy Physics - Experiment;Nuclear Theory