* Everyone has hair on their stomach. It's called vellus hair, and it's very fine and light-colored. Both males and females have it all over their bodies.
* Hormones play a role. During puberty, hormone levels change for both boys and girls. These changes can cause some vellus hair to become thicker and darker, a process called terminal hair growth. This can happen on the stomach, but it's more noticeable in some people than others.
* Genetics matter. The amount and location of hair growth is largely determined by genetics. Some families have a tendency towards more body hair, while others have less.
* Other factors: Things like weight, ethnicity, and health conditions can also influence hair growth patterns.
It's important to remember that everyone's body is different and there's no "normal" when it comes to hair growth. If you're concerned about your hair growth, it's best to talk to a healthcare professional. They can help you understand your body and any potential underlying causes.