If the food works well for you dog it shouldn't affect their shedding. I change foods every month and notice no change in shedding, until I added in a grain inclusive Acana.
My three got horrible at the begining of December, I could sweep the house 3 times a day and get dustpan fulls, it was crazy. But it was their usual time. I'll go through it all over again come spring. Ugh.