Yes avoid corn, peas, carrots, fruits and store bought treats. If he doesn't show signs of diabetes (peeing and drinking a lot are signs) then he can have some of these veggies/fruits once in awhile but sometimes they are good at hiding it.
You could try the suebees mix without any fruits but dwarfs like smaller seeds & grains so here are some suggestions that could be added in to suebee's:
Grains
Armaranth
Quinoa
Millets
Buckwheats
Rye
Wheat
Oat
Barley
Brown Rice
Jacob's tears
Wild Rice
Multi Rice
Seeds
Black Sesame
White Sesame
Goldenflax seeds
Sunflower seeds
Safflower seeds
Pumpkin seeds
Canary seeds
Hemp seeds
Brownflax seeds
As for gender:
http://hamsterhideout.com/forum/index.php?showtopic=10517Meat as someone else mentioned is alright. Stay away from fatty meats. I like to give mine some plain chicken.
Also may I ask what cage he/she is in? Dwarfs tend to get cage aggressive in small cages.

Good luck =D