The Short Answer
Both TUDCA and milk thistle are popular liver support supplements — but they work in completely different ways and suit different goals. If you're training hard, cycling, or putting serious stress on your liver, TUDCA is the more targeted option. If you want general everyday liver maintenance, milk thistle holds up fine.
Let's break it down properly.
What Is TUDCA?
TUDCA (tauroursodeoxycholic acid) is a bile acid that occurs naturally in the body. It's been studied extensively for its role in supporting bile flow and cellular health in liver tissue. Originally used in clinical settings in Europe and Asia, TUDCA has become increasingly popular among athletes and gym-goers who want dedicated liver support during periods of heavy physical stress.
TUDCA works by supporting the integrity of liver cells under load — particularly helping maintain normal bile acid metabolism when the liver is working harder than usual.
What Is Milk Thistle?
Milk thistle (Silybum marianum) contains an active compound called silymarin, a group of flavonolignans that have antioxidant properties. It's one of the most well-researched herbal supplements for liver health and has been used in traditional medicine for centuries.
Silymarin supports liver function by acting as an antioxidant, helping to neutralise oxidative stress in liver cells. It's gentle, well-tolerated, and widely available.
Key Differences: TUDCA vs Milk Thistle
Mechanism: TUDCA works at the level of bile acid transport and cellular membrane stability. Milk thistle's silymarin acts primarily as an antioxidant. These are fundamentally different pathways — which is why some athletes choose to stack both.
Research depth: Both have solid research, but TUDCA has been studied in the context of more acute liver challenges, while milk thistle research is broader and longer-established for general liver maintenance.
Speed of action: TUDCA tends to be considered more targeted for acute or performance-related liver support. Milk thistle is typically seen as a longer-term maintenance supplement.
Cost: TUDCA is generally more expensive than milk thistle. If budget matters, milk thistle is the accessible option for everyday support.
Who Should Consider TUDCA?
TUDCA is commonly used by:
- Athletes training at high volume who want dedicated liver support
- People who regularly consume alcohol and want to maintain liver health
- Anyone completing a supplement cycle who prioritises liver maintenance as part of their post-cycle support stack
- Those who've tried milk thistle and want a more targeted option
If you're training seriously — five to six days a week, eating in a surplus, supplementing aggressively — TUDCA is worth having on hand.
Who Should Consider Milk Thistle?
Milk thistle suits people who:
- Want a gentle, affordable daily liver supplement
- Prefer a well-established herbal option
- Are newer to liver support supplementation
- Want to stack a broad-spectrum antioxidant alongside TUDCA
Can You Take Both?
Yes — TUDCA and milk thistle are commonly stacked together. They act on different pathways, so there's no redundancy. Many experienced athletes take TUDCA as their primary liver support compound and add milk thistle (or NAC) for additional antioxidant coverage.
FITCNT's TUDCA supplement is formulated specifically for athletes who want a clean, high-quality source of tauroursodeoxycholic acid without unnecessary fillers.
Dosing Guidelines
TUDCA: Most studies and athlete protocols use 250–500mg per day. FITCNT's formula delivers 500mg per serving, which aligns with the commonly referenced dosing range in the literature.
Milk thistle: Standard doses are typically 140–420mg of silymarin per day, often taken with food.
Always follow the label directions for the specific product you're using.
Are These Supplements Legal in Australia?
Yes. Both TUDCA and milk thistle are legal to purchase and use in Australia. They are not prohibited substances under ASADA (Australian Sports Anti-Doping Authority) guidelines. FITCNT's TUDCA is manufactured to strict quality standards and is sold as a dietary supplement.
For more on this, read our detailed guide: Is TUDCA Legal in Australia? A Buyer's Guide.
The Bottom Line
If you're a serious athlete or someone who regularly challenges their liver — through training, alcohol, or supplement use — TUDCA offers a more targeted form of liver support than milk thistle alone. Milk thistle remains an excellent, well-studied antioxidant option and works well alongside TUDCA for comprehensive coverage.
For those who want a single, high-quality TUDCA supplement designed for athletes, FITCNT TUDCA is available now.
References
- Hagey LR, et al. "Tauroursodeoxycholic acid." Digestive Diseases and Sciences. 2014. PubMed
- Surai PF. "Silymarin as a Natural Antioxidant: An Overview of the Current Evidence and Future Perspectives." Antioxidants. 2015. PubMed
- Beuers U, et al. "Ursodeoxycholic acid in cholestasis: potential mechanisms of action and therapeutic applications." Hepatology. 1998. PubMed