Cats have four different types of hair. Down, awn, guard and vibrissae. Guard is the outer layer of hair and down (usually shorter) is the super soft under coat. Awn hair are longer than down but shorter than guard – these contain the patterning and colouring. Vibrissae are the whiskers. Overgrooming and lots of hairballs could be a sign of infestation with parasites, human house dust mites (yes this happens over time), stress, allergies or other reasons. It is important to groom cats regularly and with the right products.
The way the liver functions in cats is very different to other animals. The liver is responsible for processing toxins, drugs and metabolic products such as ammonia (waste by product). Cats are thought to lack one major enzyme system that aids in getting rid of these toxins and waste byproducts. This makes them more susceptible to chemicals in their grooming products compared to dogs and humans. Ensure you buy your cat products from manufacturers who have done their due diligence.