What is an optimal GGT level?
The short answer
An optimal GGT level is under 20 U/L. That is Dr. Mark Hyman's number. You can watch him say it below.
Most labs call GGT high only above 55. So your report can call 38 normal while it sits above where he draws the line.
“so between a gtt between 15 and 20 means you've done a good job of getting rid of enough toxins that the body doesn't have to increase gtt”
Where a number lands, and who said so
- under 20 U/L The range Dr. Mark Hyman draws
- 20–55 U/L Normal on most reports. Above optimal Dr. Mark Hyman · 23:47 →
- over 55 U/L Most labs flag this as high
What GGT measures
An enzyme concentrated in the liver and bile ducts.
Alcohol and bile-flow problems move it, so it helps explain why another liver enzyme has climbed.
Checked against MedlinePlus — Gamma-glutamyl Transferase (GGT) Test.
One of the doctors we cite, on why it matters
“so between a gtt between 15 and 20 means you've done a good job of getting rid of enough toxins that the body doesn't have to increase gtt”
Common questions
What is an optimal GGT level?
Under 20 U/L, according to Dr. Mark Hyman.
What is a normal GGT level?
Most US labs print 0–55 U/L. Your report grades you against that range. It exists to catch disease, not to describe your best.
What does your GGT number mean?
Under 0 U/L, your report marks it low. Between 0 and 55 it prints as normal. Over 55, your report marks it high. Where the people we follow draw their own line is above.
Is GGT of 38 normal?
Your lab will call it normal. Dr. Mark Hyman puts the ceiling at 20 U/L, so by that number it is high.
What does the GGT test measure?
An enzyme concentrated in the liver and bile ducts. Alcohol and bile-flow problems move it, so it helps explain why another liver enzyme has climbed.
Where does this number come from?
Dr. Mark Hyman, on video. The link above jumps straight to that minute.