Just simple affirmations. I personally just visualize white gold energy filling it (not sure other colors might be more efficient) and affirm "This food is very nutritious and healthy for me, in the most beneficial way for me", 1-3 times. I often don't say the most beneficial way for me as I don't find it particularly important in this case as you affirm it's healthy for you already.
Do the same with water or anything you consume basically.