It means your ejaculate has a higher concentrate of just water in it. Doesn't effect anything. Don't come for a few days and see if has some white to it then.

It also means you've been masturbating excessivley. Give it up or take long breaks in between at least 3 weeks and get plenty of nutrients in you.

Eat cheese ;)

works wonders

Ummm I masturbate like once a week

Ummmm I see.... Can I ask what your eating pattern is like?