The only thing I can think would be different in the Men's version is higher protein in the Shakes, and that would be printed both on the boxes and packets themselves
There is a "55" Shake with 11 grams of protein for women, and a "70" Shake with 14 grams, for men or very active women.
Looking at the Medifast site, it's odd that they don't say WHAT the difference is, heh! I suspect it is the protein level in the shakes.
You can call them to confirm though if you want to know for sure: 1-800-209-0878
Congrats on starting up!