Will getting a breast lift reduce the sensitivity in the nipple area?

Possibly. Any breast surgery has the potential to alter the sensation in the nipple, however it is uncommon to have a permanent loss of sensation with a breat lift.
Yes it may. Yes it may and it will depend primarily on the extent of the lift.
Breast lift/numb. It is a possibility. Best to discuss this issue in person with a boarded Plastic surgeon...
Possible. Most techniques will not affect the sensitivity, but it is approximately a 10% risk.
Possibly. Most of the time, a lift alone (depending on the type of lift and how extensive it is) will not disrupt sensation, however it is always a risk.
Unknown. Usually, nipple sensation is decreased after breast surgery. But it would be impossible to predict if nipple sensitivity would decrease.