Instructions
Feed your cat a high-quality cat food. The food should not contain any meat byproducts, but should contain important amino acids for cat nutrition, including taurine, methionine, arginine and cysteine, with taurine being the most important for a cat's diet.
Measure out the amount of cat food your cat should have in a day to gain weight. This will depend on your cat's current weight and age and how much weight needs to be gained. It will usually be somewhere between 1/2-cup and one cup per day. Follow the recommendations of your veterinarian.
Split the food portion for the day into two. Feed your cat half the food in the morning and leave it in the bowl all day. Toward the evening, feed your cat the other half.
Give your cat treats during the day. Treats can consist of about five percent of your cat's daily diet and calorie intake. Be sure to follow the recommendations for high-quality cat food when choosing treats.
How to Get a Cat to Gain Weight By Eating More
Thin cats with very active lifestyles or those who have become underweight due to inactivity or illness should be put on a special program to help the cat gain the weight back by eating more. You should always follow the recommendations and treatment course outlined by your veterinarian. However, there are some basic guidelines that most cat owners should be able to follow when trying to help their cats gain weight by offering more food at feeding time.