|Science Diet m/d||Science Diet Mature Adult Indoor||Purina Healthful Life|
Science Diet m/d is their weight loss and diabetes prevention diet. It's a prescription diet* that you can only buy at a vet's office. It looks to me like Healthful life compares reasonably well with Mature Adult Indoor. Regular Science Diet food can only be found at pet stores. I've got to take Her Serene Furriness in for a vet appointment soon and when I do I'll pose the question for them, but until then, it doesn't look like I'm doing any harm feeding her Healthful Life.
* - A prescription diet?!? Huh?