Depending on the issue, you may have to pick your battles (maybe it's okay if Grandma buys treats for her beloved grandchild
once in a while) or meet somewhere in the middle (ask her to buy whole -
grain muffins instead of doughnuts).
Granted, foods like potatoes, rice, and other gluten - free
grains are perhaps better for my health, but a chocolate chip
muffin is absolutely okay in my book every
once in awhile.