🏥 Hepatobiliary system: NAC, silymarin and TUDCA for liver protection
Three key agents for supporting the liver and bile ducts
The liver performs hundreds of functions: from detoxification and protein synthesis to bile production. The gallbladder stores and releases bile to digest fats. Together they form the hepatobiliary system. Among supplements supporting it, NAC, silymarin and TUDCA are most often discussed. Let's look at how they work.
Liver and bile: basics
The liver neutralizes toxins in two stages (phase I and phase II). A key antioxidant protecting liver cells is glutathione. For more on detoxification physiology — see "Detox and liver support: physiology vs marketing".
Bile helps digest fats and remove waste products. Bile stasis (cholestasis) disrupts this process. TUDCA and other agents are used to support bile flow.
NAC and glutathione
N-acetylcysteine (NAC) is the amino acid cysteine in acetylated form. The main role of NAC is to be a precursor for glutathione synthesis. More — in "NAC: from mucolytic to glutathione" and on glutathione synthesis.
- Raises glutathione — the liver's main antioxidant.
- Used for paracetamol poisoning (in hospital).
- Supports detoxification and antioxidant defense.
Silymarin (milk thistle)
Silymarin is a complex of flavonolignans from milk thistle (Silybum marianum), the main one being silibin. Silymarin is studied as an agent supporting liver health.
- Antioxidant and anti-inflammatory action.
- Support of liver cell recovery.
- Used for fatty liver disease and toxic damage.
A standardized extract usually contains 70–80% silymarin. A common dose is 140 mg of silibin 2–3 times a day.
TUDCA for bile flow
Tauroursodeoxycholic acid (TUDCA) is a bile acid used to support bile secretion and protect liver cells. It belongs to the so-called hydrophilic bile acids, which help dissolve gallstones (in combination with ursodeoxycholic acid).
- Improves bile flow.
- Protects liver cells from damage.
- Used for cholestasis and biliary disorders.
Comparison and choice
| Agent | Main action | When suitable |
|---|---|---|
| NAC | Raises glutathione, antioxidant | Detoxification, antioxidant support |
| Silymarin | Protects and restores liver cells | Fatty liver, toxic loads |
| TUDCA | Improves bile flow | Bile stasis, biliary disorders |
What is the hepatobiliary system?
It is the liver and bile ducts, including the gallbladder. The liver detoxifies, and bile helps digest fats.
What is NAC?
N-acetylcysteine — an amino acid, a precursor of glutathione synthesis, the liver's main antioxidant.
What is silymarin?
A complex of flavonolignans from milk thistle (mainly silibin), supporting liver health and recovery.
What is TUDCA?
Tauroursodeoxycholic (hydrophilic) bile acid that improves bile flow and protects liver cells.
Why does the liver need glutathione?
Glutathione is the liver's main antioxidant, neutralizing toxins and free radicals during detoxification.
What is the NAC dose for the liver?
Studies use 600–1200 mg a day, better with food.
Does milk thistle help fatty liver?
Some studies show support in fatty liver disease, but the effect is moderate and requires a comprehensive approach.
Can TUDCA be taken with gallstones?
Only as prescribed by a doctor. With stones and jaundice, self-medication is dangerous.
Can NAC, silymarin and TUDCA be combined?
They are often combined, but with liver disease it is better to agree with a doctor.
When to see a doctor for liver problems?
With jaundice, pain in the right upper abdomen, nausea and digestive disorders — be sure to see a doctor.