My diabetic cat weighs about 19 lbs when his ideal weight
is about 16 lbs or less.

According to the instruction on the Purina DM bag, a cat
weighing between 17 and 20 lbs should get 108-144 g of
food per day.

If I give him 108 g of Purina DM per day he would still keep
gaining weight. If I give him 100 g per day he still won't lose
any weight.

Should I try giving him only about 90 g a day ?

Thanks everyone.