All cats have basic needs that must be met, and all good cat owners easily meet them. Food, water, shelter, and love are among the most essential necessities in a cat’s life.

Although it is not possible to provide a cat with too much love, food is a different matter. The much-touted obesity epidemic is not limited to human beings in the developed world. Obesity is one of the most common health issues faced by our feline friends.

The feline health issues linked to obesity are myriad. Obesity may trigger insulin resistance and subsequent diabetes in cats. Obesity can exacerbate heart disease (although unlike their human owners, cats’ heart disease is rarely caused by obesity alone), kidney disease, idiopathic cystitis, bronchitis (also known as feline asthma) and arthritis. Cats whose girth precludes adequate grooming may smell bad or develop urinary tract infections due to chronically soiled private parts.

There is no question about it: Cats who are kept at healthy body weights live longer and healthier lives on average.

Although fad diets look likely to be forever popular in America, most people know that there are two basic ways to modify one’s weight. One can alter the number of calories consumed (by eating less, or by eating lower calorie food), or one can increase the number of calories burned (by getting off the sofa and exercising). Most cats are by nature couch potatoes; therefore, owners who care about their cat’s weight tend to focus on one question: How much should cats be fed?

Before we delve into the answer to that question, I’d like to look a little more carefully at one of the assumptions embedded in it. Namely, I take issue with the idea that cats can’t be inspired to exercise.

Of course, if you or your dog need to lose weight, then going for more and longer walks is one of the best steps to take. I know some people who have successfully walked their cats on leashes, but most cat walking attempts of which I’m aware have ended in comical failure. A general feline un-walkability, however, should not be confused with it being impossible to motivate cats to exercise.

Laser pointers and toys that feature some variation of a feather on a string can in fact trigger significant activity in many cats. And if you’re creative, even cats who don’t like to chase feathers can be inspired to exercise. If you live in a three-story house where most of the living occurs on the ground floor, then consider feeding your cat on the third floor. If you’re worried about your cat’s weight, he is likely to be a food-motivated individual who will respond well to this tactic. Use of toys that slowly release food when played with also can motivate many cats. So don’t write off exercise as a weight-management tactic in cats.

But let’s go back to the question at hand. How much should cats be fed?

Forgive me for answering with a non-answer, but here goes: Cats should be fed the amount of food that maintains a healthy body weight.

That quantity varies massively among individuals based on activity, age, and baseline metabolism. Nutritionists and physiologists have devised complicated formulas to calculate caloric needs for cats. In my opinion most of those formulas are bunk. There is no cookie-cutter answer to the question of meal size in cats.

For an example of the uselessness of caloric rules of thumb we need look no further than our human friends. There are basic rules for calorie consumption in people — adult men are usually advised to eat about 2,500 calories per day, and adult women are advised to eat around 2,200. And even rudimentary familiarity with individual differences in life shows that those rules boil down to hogwash.

We have all known lucky people who could eat four Big Mac combo meals each day and stay rail thin. We have also known unfortunate people who gain weight if they even think about a salad. Many people have experienced both extremes as they have aged and their metabolisms have slowed (and many of those people have continued to eat four Big Mac combo meals per day with predictable results). What I’m saying is that every individual — human and feline — has very unique caloric needs. Each person and cat needs to consume the quantity of food that is appropriate for his or her personal needs. No formula will work to calculate those needs. It boils down to trial and error.

Feeding of dogs in most instances is a simple matter. Most of them will eat any quantity of food that is offered. If I put out 20 pounds of dog food, my pal Buster would do his best to consume it all (and in fact there is a common condition in dogs called food bloat in which they gain access to an unlimited quantity of food and consume massive quantities).

Cats take a more nuanced approach to life. A minority of cats, which happily includes my new friend Abbey, will graze at an all-you-can-eat cat food buffet intermittently and maintain an ideal weight. The bigger challenge in my house is keeping Buster away from the bowl.

Most cats, however, are not like Abbey. If an unlimited amount of food is offered, most cats will overeat and become overweight.

So for most cat owners the best plan is this: Pick a high-quality food that is complete and balanced, and feed it in meals. Tinker with the size of the meals in order to maintain your cat at a healthy weight.

It’s not a very scientific answer to the question of how much a cat should be fed, but it also shouldn’t come as a surprise. After all, most people reading this probably adjust their food intake (or at least know that they should adjust their food intake) in the exact same manner.

Learn more about your cat with Catster:

• Weird Cat Facts: 8 Reasons Your Cat Likes to Lick You
• 10 Sounds That Cats Make — and What They Mean
• 8 Things to Try When Your Cat Won’t Eat

Got a question for Dr. Barchas? Ask our vet in the comments below and you might be featured in an upcoming column. (Note that if you have an emergency situation, please see your own vet immediately!)