Out of about 4,000 hours in vet school. You might be lucky if your vet got 3-5 hours of nutrition a semester, and not every year. The ladies at global pet foods seem to have far better information than my vet ever will have when it comes to nutrition.
When you go to the dr, they refer you to a nutritionist, which there are in the vet world too. Your doctor doesn't start pushing diet advice on you. Think I'd be sketched out if the doctor's office was packed with random food products.
Brewer's yeast is in mainly crappy foods. It's a by product of the brewing industry. It has some vitamin B, but it's not worth nearly enough to be anywhere near the top of any ingredients list.
Marketplace did a dog food expose. Lot of vets were making 20% of their yearl income off of pushing dog food on clients. Gee, that's not sketchy.
If you actually look into the 'vet' formulas short of very short term use they aren't worth much. The majority are full of really crappy ingedients. Like gastro formulas made up of maily corn. Because that's gentle on a dog's stomach...
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