Veterinary practices in the country told newspaper Blick that between 20 and 40 percent of the pets they see are too fat, with cats particularly affected.
The reason? Overfeeding and lack of exercise, veterinarians told the paper.
“Indoor cats often lack the incentive to move and start to eat out of boredom,” vet Martina Schybli told the paper.
To reduce the problem, experts suggest getting rid of a fixed feeding area for the pets and making them work for their food by using rolling food containers or placing the bowl in a different place each day so they have to ‘hunt' it out.
However putting your cat on a leash and taking it for a walk is not recommended, since it can be stressful for a pet which usually stays indoors.
Cats are the most popular pet in Switzerland.
Since the majority of Swiss residents live in rented apartments, indoor cats are common.
To ensure that cats lead a happy life and do not get bored, Zurich Animal Protection Association recommends that a household have more than one cat, or other pets, so they can be companions for each other.
Owners should ensure variety in their furry friend's day by introducing games that appeal to a cat's hunting instincts, it adds.
If there is only one cat in a household then Swiss animal protection laws specify that they cannot be kept indoors all the time and must have access to outdoor space at least five days a week.
Solo cats must have contact with their owners or other cats every day.