Could there be a cause for dizziness?

I've had a few dizzy spells recently. I've felt dizzy on the way to the bathroom, holding onto the wall to stand, and even felt dizzy a few times while walking.

I have fallen down in the past after standing for a long time, but at the time, I only ate when I felt like it, had an unbalanced diet (I liked to drink only drinks with high fructose corn syrup), and my blood pressure was low, so it was understandable.

But now my blood pressure is 100/70, which is normal. It's a problem because I eat so well compared to back then. I eat a diet that's high in protein and vegetables, starting with meat and shabu-shabu, but do I need to supplement my diet with more health supplements?

Or is there something else wrong with my health?