  In the light of recent results detecting the nearest starburst galaxies M 82
and NGC 253 at very high energy (VHE), we present a multi-wavelength model
succesfully explaining their gamma-ray diffuse emission. The detection of M 82
was presented by VERITAS collaboration in the recent ICRC, while the integral
flux of the fainter NGC253 has just been published by HESS Collaboration. Also,
in the 2009 Fermi Symposium itself, Fermi data coming from the direction of
both galaxies was released, thus confirming their detection in the high energy
(HE) regime. Slight and reasonable variations in the space parameter of already
published models can fully account for the HE and VHE emission coming from M 82
and NGC 253, while agreeing with previous data detected from radio to infrared.
We explore these changes and the implications they have for the cosmic-ray
distribution in these galaxies.
