Impaired fasting gluc. i already eat healthy, low gi foods and exercise plenty. if i develop type 2 does this cut my life shorter? by how much?

Not necessarily: Hi. It sounds like you're living right. Keep that up. If you develop diabetes despite healthy lifestyle, it is essential to tightly control your diabetes (blood sugar maintained as close to normal as possible), your blood pressure, and your lipids. I already assume you don't smoke since you're living healthily. If you do all that and keep eating healthily and exercising, you should live long life