Owners should only feed their animals pet food and must not give in to their begging eyes and provide them with titbits from the dinner table.
That is according to Battersea Dogs & Cats Home, which is warning owners about the dangers of feeding animals too much and them becoming obese.
The charity notes that the food equivalent for pets for a chipolata sausage is a 12oz steak, while a 3cm cube of cheese amounts to a cup of fondue cheese.
One custard cream biscuit is equivalent to half a pack, and a few ready salted crisps is the same as a human eating a slice of pepperoni pizza.
Battersea Vet Phil Robinson says: "The amount a pet needs to eat depends on its breed, age and size, but as a rough indication, a small dog only needs about 350 calories a day while a cat is looking at about 280 calories.
"Don't fall for those appealing eyes when you're eating your dinner, as your pet simply doesn't need your scraps."
To help a pet stay in shape, the vet suggests banning all human food and sticking to the guidelines provided on pet food products, as they are based on your animal's weight and the correct amount can easily be calculated.