The store clerk did not give you bad advice - what they said is actually fine/true. "All Life Stages" foods are okay for pups and adults - that's what all life stages means. And it's true, eating the same food over and over can potentiate any vulnerabilities toward allergies. This is why it IS a good idea to rotate protein and carb sources -- BUT, always save ("save" = don't feed!) a few novel proteins in case of allergies later in life.
If you're trying to avoid allergies, one of the worst foods to put your kiddo on is Royal Canin. Corn is a horrible allergen for canines - and I personally won't feed my dogs anything w/ corn. I firmly believe in grain-free kibbles; also believe in higher-protein foods/kibbles rather than higher-carb.
As for why your pup lost weight, it's likely that he needed larger portions. And Acana would not cause the weight loss. Acana is a very nice food, btw. Hypoglycemia doesn't cause weight loss. Hypoglycemia is due to low blood sugar.
If looking for something different than Royal Canin - I recommend Natures Logic, Natures Variety Raw Boost Instinct, Solid Gold Wee Bit (tiny kibbles are nice), Wellness Core.
I feed raw and have for about 8 years - LOVE it for my kiddos. I feed Better In The Raw or Primal.
__________________ ~ A friend told me I was delusional. I nearly fell off my unicorn. ~
°¨¨¨°ºOº°¨¨¨° Ann | Pfeiffer | Marcel Verdel Purcell | Wylie | Artie °¨¨¨°ºOº°¨¨¨° |