How much Milk thistle should I take daily?
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Optimal Daily Dosage of Milk Thistle (Silybum marianum)
Introduction to Milk Thistle and Its Benefits
Milk thistle (Silybum marianum) is a popular herbal supplement known for its potential benefits in liver health and antioxidant properties. The active compounds in milk thistle, primarily flavonolignans such as silybin, isosilybin, silychristin, and silydianin, are collectively known as silymarin. These compounds are believed to offer various therapeutic effects, including liver protection and antioxidant activity.
Recommended Daily Dosage
Clinical Studies on Dosage
Several studies have investigated the appropriate daily dosage of milk thistle for different purposes. One study involving healthy volunteers assessed the pharmacokinetics of milk thistle flavonolignans at different dosages. Participants received single doses of 175 mg, 350 mg, or 525 mg of milk thistle extract, and the results indicated that all six major flavonolignans were rapidly absorbed and eliminated. The study also evaluated the effects of a steady-state dosage, where subjects took 175 mg three times daily for 28 days. This regimen showed a linear and dose-proportional systemic exposure to the flavonolignans.
Supplementation in Healthy Volunteers
Another study focused on the effects of milk thistle supplementation on digoxin pharmacokinetics in healthy volunteers. Participants were given a standardized milk thistle supplement at a dosage of 900 mg daily for 14 days. The study found no statistically significant effects on digoxin pharmacokinetics, suggesting that this dosage is safe and does not significantly interact with P-glycoprotein substrates.
Digestibility and Nutrient Absorption
Research on the digestibility of milk thistle in horses, although not directly applicable to humans, provides insights into the absorption and effectiveness of different dosages. The study administered varying daily doses of milk thistle seed cakes (ranging from 0 g to 700 g) and found that the digestibility of flavonolignans increased with the dose but plateaued at 700 g/day. This suggests that there may be a threshold beyond which higher doses do not result in increased benefits.
Conclusion
Based on the available research, a daily dosage of 900 mg of milk thistle extract appears to be effective and safe for supplementation in healthy adults. For those looking to achieve steady-state benefits, a regimen of 175 mg taken three times daily (totaling 525 mg per day) over an extended period may also be beneficial. It is important to note that individual responses to supplementation can vary, and consulting with a healthcare provider before starting any new supplement regimen is advisable.
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