Carbohydrate Digestion By The Domestic Cat (Felis Catus)

This 1977 study examined how domestic cats process different types of carbohydrates in their diet, which is relevant for understanding carbohydrate metabolism across species. Researchers fed adult cats various forms of carbohydrates including glucose, sucrose, lactose, starch from corn and wheat, and cellulose, then measured how well they could digest each type.

The results showed that cats are surprisingly good at digesting most carbohydrates, with digestion rates above 94% for glucose, sucrose, and processed starches. However, they struggled with two types: cellulose (which is indigestible fiber) and lactose (milk sugar), which caused diarrhea in some cats and interfered with protein digestion. The study also found that processing matters - finely ground grains were much easier to digest than coarsely ground ones, and cooking helped improve digestibility.

Interestingly, when researchers examined kittens, they discovered that the enzymes needed to digest lactose naturally decrease with age, explaining why adult cats often become lactose intolerant. This mirrors what happens in many humans who lose the ability to digest dairy as they mature.

For metabolic health, this research highlights how carnivorous species have adapted to process carbohydrates despite their meat-based evolutionary diet. In clinical practice, this research contributed to our understanding of how different species handle carbohydrates and informed better pet nutrition, while also providing insights into digestive enzyme adaptation that applies broadly to mammalian metabolism.