High GGT Levels

I recently had bloodwork completed for life insurance and everything was normal except for the following:
Alkaline Phosphatase - 133
GGT - 202
Protein Quantitative 27

I'm 33, 5'5", 125 pounds, I drink a couple glasses of wine throughout the week, smoke about 2 packs per week and am in reatively good health.  Could smoking be the cause of any of this?  I plan to schedule an appointment with my physician soon, but would like any type of information that could point to the cause of the elevated levels mentioned above.