If the brake fluid level is low, have the brakes inspected:
A low brake fluid level is dangerous.
A low level could indicate brake lining wear or a brake system leak which could cause the brakes to fail and lead to an accident.
Inspect the fluid level in the reservoir regularly. It should be kept between the MAX and MIN lines.
The level normally drops with accumulated distance, a condition associated with wear of brake linings. If it is excessively low, have the brake system inspected by an Authorized Mazda Dealer.