What are liver enzymes (liver values)?
The term "liver enzymes" has two meanings. In the lab it refers to blood values such as ALT (GPT) and AST (GOT), which can point to strain on liver cells. In biochemistry it means the liver's enzymes that break down drugs and foreign substances.
Liver values: ALT, AST and others
When your doctor checks "your liver values", the following enzymes are usually measured in the blood:
- ALT (GPT): found mainly in liver cells; a rise suggests cell damage.
- AST (GOT): also present in heart and skeletal muscle, so less liver-specific.
- Gamma-GT: responds to alcohol, medication and bile duct problems, among other things.
- Alkaline phosphatase (ALP): often raised in bile duct disease.
Elevated values are a pointer, not a diagnosis. They can result from medication, alcohol, fatty liver, infections, intense exercise or liver disease.
Key liver values at a glance
For orientation, not a diagnostic aid.
| Value | Alternative name | Meaning |
|---|---|---|
| Value ALT | Alternative name GPT | Meaning hint of liver cell strain |
| Value AST | Alternative name GOT | Meaning liver and muscle |
| Value Gamma-GT | Alternative name GGT | Meaning alcohol, drugs, bile ducts |
| Value ALP | Alternative name alkaline phosphatase | Meaning bile ducts, bone |
Liver enzymes as a breakdown machinery
In the second sense, liver enzymes are the tools the liver uses to break down foreign substances, above all the cytochrome P450 family such as CYP3A4. Piperine blocks some of these enzymes. This increases curcumin uptake but can also slow the breakdown of medicines and strengthen their effect.
Liver values and curcumin: what studies and reports show
Curcumin is investigated in numerous studies in connection with the liver. Whether this translates into a benefit for humans is not established; there is no authorised health claim. At the same time, isolated cases of liver injury linked to curcumin products have been reported. In a 2023 case series of ten patients from the US DILIN network, all seven products tested contained turmeric and three of them also contained piperine. Seven of the ten patients carried the genetic marker HLA-B*35:01, which points to an individually predisposed reaction. The risk is considered low, especially with properly tested products, but it is not zero. More under hepatotoxicity.
Frequently asked questions
Which liver values are normal? Reference ranges differ by laboratory, sex and method. Results are read in context with symptoms and history. Mildly raised values are common and often harmless, for example after alcohol, exercise or infections.
Should I have my liver values checked before taking curcumin? With known liver disease, medication that stresses the liver or regular alcohol consumption, medical advice makes sense. A look at liver values can support the decision.
Can alcohol or a supplement change my liver values? In principle, yes, both can influence them. That is why supplement use is something you should mention at lab check-ups.
Yellowing of skin or eyes, dark urine, persistent nausea or pain in the upper right abdomen are warning signs. Stop the product and seek medical help. With liver disease or regular medication, talk to your doctor before use. Not medical advice.
