My cat is very overweight, do I need to help him?

Don't try putting your cat on a crash diet by yourself, because it can do more harm than good. The first step is taking him to the vet to rule out any health issues and figure out how much weight he actually needs to lose. From there it's a matter of adjusting his food (both the amount and type), increasing his physical activity with play and toys, and being patient - a fat cat won't slim down overnight.

Yes, it's worth dealing with this because obese cats have serious problems - their joints suffer, diabetes shows up easily, and their quality of life becomes terrible. But before you start cutting food, take him to the vet first. There could be a lazy thyroid or something else going on, and the vet will tell you how much weight it's safe to lose per month.

After that, the annoying part is really discipline. Less food at main meals, more fiber (some cats do fine with weight control food), and don't leave food out all day. Also play with him more - a laser pointer or a feather toy for 10 minutes, twice a day, makes a real difference. It might seem like little but a sedentary cat is a cat that gets fat.

One trick that works well: if he meows constantly for food, put it in high places or inside a box with a small hole. It forces the cat to work to eat and he burns more calories in the process. It changes the dynamic - it's not just him walking to the food bowl anymore, it's him having to "hunt" for the food even if it's inside the house.

I agree that the vet is essential, but you can't just sit around waiting too long to start doing something. While you're booking the appointment, you can already cut back on his food portions and spend more time playing with him - fat cats are lazy, they need the stimulus. Once the vet rules out thyroid problems or whatever else, it'll be easier to adjust his diet without risk. The hard part is having patience, because cats lose weight slowly.