Lever
Lifestyle
- Reduce alcohol intake
- Maintain a healthy weight
- Engage in regular exercise
Blutwerte · Marker
ALT (GPT)
Alanin-Aminotransferase · ALAT · GPT · SGPT
LeberwerteZeitabhängig
- Einheit:
- IU/L
- Abbreviation
- ALT / GPT
ALT quantifies the enzyme alanine aminotransferase, which is involved in amino acid metabolism and is indicative of liver cell integrity.
Reference Ranges
Reference
7–56IU/L
7
10
30
56
LowNormalHigh
Reference
Optimal
Unit · IU/LReference ranges may vary slightly depending on the laboratory and population. ALT levels can be higher in males and may vary with age.
Overview
Übersicht
ALT (GPT), also known as Alanine Aminotransferase, is an enzyme primarily found in the liver. It plays a crucial role in amino acid metabolism by catalyzing the conversion of alanine and α-ketoglutarate to pyruvate and glutamate. This enzyme is released into the bloodstream when liver cells are damaged, making it a valuable marker for liver health. Clinically, ALT is a key indicator of liver function and is often measured to assess liver damage or disease. Elevated levels of ALT can indicate liver conditions such as hepatitis, cirrhosis, or non-alcoholic fatty liver disease (NAFLD). It may also reflect liver damage due to toxins, infections, or medications. In the context of athletic performance and biohacking, ALT levels can be monitored to ensure liver health, especially in individuals using performance-enhancing substances or undergoing intense training regimens. However, ALT levels can be influenced by factors such as exercise, medications, and alcohol consumption, which may confound results. Researchers have found that ALT levels can vary throughout the day and may be affected by fasting status, thus standardizing testing conditions is recommended for accurate interpretation.
Klinische Bedeutung
Elevated ALT levels typically indicate liver damage or inflammation, which can be due to conditions such as hepatitis, fatty liver disease, or drug-induced liver injury. Low ALT levels are generally not clinically significant but can occur in cases of severe liver damage where enzyme production is impaired.
Dynamics
Trend Interpretation
Rising Values
Progressively rising ALT values suggest worsening liver function and warrant further investigation and possible lifestyle or medical intervention. Retest in 4 weeks if outside the optimal range.
Falling Values
Falling ALT values may indicate improvement in liver health or resolution of an acute liver issue.
Re-test Interval
4 weeks if outside optimal range
Etiology
Causes — High & Low
Cause
Elevated Levels
- Liver disease
- Alcohol consumption
- Medication side effects
- Viral hepatitis
- Non-alcoholic fatty liver disease
Cause
Low Levels
- Severe liver damage
- Vitamin B6 deficiency
- Uremia
- Malnutrition
Protocol
How to Optimize
Lever
Nutrition
- Increase intake of fruits and vegetables
- Consume omega-3 fatty acids
- Limit saturated fats
Lever
Supplementation
- Milk thistle
- N-acetylcysteine
Note:
Consult a healthcare provider before starting any new supplement, especially if you have liver disease.
Testing Guidelines
✓Fasting Not Required
🕐Time-Sensitive
ALT levels may vary throughout the day; testing at the same time of day is recommended for consistency.
Testing Frequency
Annually for healthy adults, more frequently if monitoring liver disease.
Interfering Factors
- Recent intense exercise
- Alcohol consumption
- Certain medications
Related Peptides & Hormones
Igf 1
hormone or peptideCorrelated with
Open Research Questions
Current research suggests that the reference ranges for ALT may not adequately reflect the severity of liver conditions, particularly in non-alcoholic fatty liver disease (NAFLD), where its predictive value remains debated. Researchers have not yet established optimal ALT targets for monitoring cognitive decline in atrial fibrillation patients. Additionally, clinical questions remain unanswered regarding the role of ALT in distinguishing between different types of liver injury and its relationship with long-term outcomes in various diseases.
25 Research Publications
347
Total Citations
17
Human/RCT
3.0
Avg. Influence
2025
Latest
Sort
Filter
01Top
#01
A meta-analysis of potential biomarkers associated with severity of coronavirus disease 2019 (COVID-19).
Meta-AnalysisInfluence6.0
148
Researchers conducted a meta-analysis to summarize biomarkers associated with the severity of COVID-19. They found that ALAT levels were significantly elevated in severe cases compared to non-severe cases. This suggests that ALAT, among other biomarkers, can help in prognostic risk stratification for COVID-19 patients.
02Top
#02
Use of enzymes for the diagnosis of alcohol-related organ damage.
ReviewInfluence3.0
88
This study examined the use of serum enzymes, including ALT, in diagnosing alcohol-related organ damage. Researchers found that elevated ALT levels indicate alcohol-induced organ damage but noted variability in sensitivity and specificity. The study suggests that enzyme combinations improve diagnostic accuracy for differentiating between alcohol-related and non-alcohol-related damage.
03Top
#03
Sarcoidosis of the liver: to treat or not to treat?
HumanInfluence2.0
45
This study explored the effects of ursodeoxycholic acid (UDCA) on liver function in patients with hepatic sarcoidosis. Researchers found that serum liver tests, including alanine aminotransferase (ALAT), improved in patients treated with UDCA compared to those who received no treatment. The study involved 17 patients and highlighted the need for further research.
04
#04
Leptospirosis in elderly patients.
HumanInfluence3.0
16
In a study of 15 elderly patients with leptospirosis, researchers observed elevated ALT levels (mean 131.3 IU/L) indicating hepatic dysfunction. The study highlighted the severe clinical manifestations of leptospirosis in this population, with a high mortality rate associated with the disease. Prompt treatment is essential for better outcomes.
05
#05
Covid-19: contribution of clinical characteristics and laboratory features for early detection of patients with high risk of severe evolution.
Human
15
This study aimed to identify clinical and laboratory predictors of severe COVID-19. Researchers found that elevated ALT levels, among other laboratory features, were associated with worse outcomes in hospitalized patients. The study provides insights into potential early warning signs for severe disease progression.
06
#06
Non-alcoholic fatty liver disease and correlation of serum alanin aminotransferase level with histopathologic findings.
HumanInfluence1.0
8
This study explored the correlation between serum ALT levels and histopathologic findings in non-alcoholic fatty liver disease (NAFLD) patients. Researchers found that ALT levels had little contribution to predicting the severity of NAFLD, as indicated by similar histopathological grades across different ALT levels. The study included 147 patients with biopsy-proven NAFLD.
07
#07
Reference intervals for 12 clinical laboratory tests in a Danish population: The Lolland-Falster Health Study.
Human
6
This study established reference intervals for various laboratory tests, including ALT, in a Danish population. Researchers found that local reference limits for ALT differed from previously established norms, indicating the need for population-specific reference ranges in clinical practice.
08
#08
Haematology and clinical blood chemistry in harbour porpoises (Phocoena phocoena) from the inner Danish waters.
Animal
6
This research presented hematology and blood chemistry data from harbour porpoises to assess population health. Researchers noted that alanine aminotransferase (ALAT) values were lower in captive porpoises compared to free-ranging individuals, suggesting environmental influences on health markers. The study included blood samples from both wild and captive porpoises.
09
#09
IL-28 and IL-29 as protective markers in subject with dengue fever.
Human
5
This study assessed the role of interleukins IL-28 and IL-29 in dengue fever patients. Researchers found that higher levels of these interleukins were associated with lower alanine aminotransferase (ALAT) levels, indicating better liver function. The study included 45 dengue patients and 24 controls.
10
#10
Biomarker and cognitive decline in atrial fibrillation: a prospective cohort study.
Krisai Philipp, et al. · Scientific reports · 2025
Human
4
This study examined the association of various biomarkers, including ALT, with cognitive decline in atrial fibrillation patients over four years. Researchers found that ALT was part of a combined prediction model with an AUC of 0.73, indicating its potential relevance in understanding cognitive decline mechanisms. The study included 1440 patients, of whom 6.5% experienced cognitive decline.
Key findings
- 01Researchers observed that patients with cognitive decline were more likely to have permanent AF and a history of stroke.
- 02The biomarkers GDF-15, Cystatin C, and high-sensitivity Troponin T were strongly associated with cognitive decline.
- 03The best prediction model for cognitive decline included several biomarkers, indicating complex underlying mechanisms such as inflammation and neuronal damage.
Publication Trend
Research publications about ALT (GPT) over time
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