Hello and thank you for submitting your question. As you may know, GGT
is a marker used to assess mostly liver
and biliary function and sometimes pancreatic function as well. Most frequently, elevations in GGT are seen when the liver is exposed to excess toxins, such as that coming from alcohol or particular medicines, which you have not listed.
Regarding your daily consumption of Diet Coke, I would address this in regard to your electrolyte and kidney
health, and I strongly urge you to increase your water consumption and decrease the Coke. I commend you for exercising daily and for maintaining a healthy diet. I also recommend you bring any new symptoms or change in health to the immediate attention of your doctor, given your history of cardiac disease.
Thank you again for submitting your question. Please let me know if I can be of any further help.