Is it true that if you neuter a cat when is young its head will not grow as big would otherwise?

That is absolutely false.

Neutering a cat has no impact on the size or growth of its head.

The size of a cat's head is determined by its genetics and overall health.

There are some common misconceptions about neutering, but this one is definitely not true.

It's important to rely on reliable sources of information about animal care, such as veterinarians or reputable animal welfare organizations.