[Tourigjm]

When you generate lift/downforce you also create an equal amount of drag. (Downforce is simply negative lift)

being aerodynamically neutral ( L = 0) is the best. teardrop/non cambered airfoil is best for low drag.

(See attachment, its the NACA 0015 airfoil. Its upper and lower surface are identical. at 0 angle of attack it generates no lift and no drag due to lift. There is still drag but its very low)