Why do humans with no ovaries or testicles need to take hormone supplements to stay healthy, but animals who have been neutered are seemingly fine and often live longer than their intact counterparts?

Question

Just something that occurred to me when thinking about my elderly cat, who’s spent almost 16 years without her uterus or ovaries to no apparent detriment.

In: Biology

Answer 1

Ovaries and testicles naturally produce hormones that effect demeanor and physical development but they aren’t require to “stay healthy.

When an animal is neutered, it has a large effect on the animal in both of those ways.

For instance, veterinarians will generally prefer to hold off on neutering a male puppy until its body has fully developed. If a male puppy is neutered while it is still growing, the dog’s bone and muscle growth will be affected.

But if a male dog never gets neutered, the hormones have a large impact on their demeanor. Once a male puppy has been neutered, the dog’s demeanor and physical development changes quite a bit.

Humans become used to the effect that the hormones have on their body and don’t want to have the changes that the lack of hormones will cause them.

People who have their ovaries or testicles removed, generally, do it for some underlying health reason besides changing their body or mental state. So they take hormone replacements to keep them the same as they were prior to loosing their hormone producing organs, ovaries or testicles.