Your liver works hard. It helps digest food, regulates cholesterol and fat metabolism, and cleans the blood of impurities, among other essential functions.
It’s no wonder then that there are dozens of dietary supplements—pills, powders, and tonics—touted to protect this vital organ. LiverCare, Liverite, Liver Plus, and Liver-Rx are but a few that claim to “neutralize toxins” and repair and regenerate the liver. Some products even claim to alleviate chronic fatigue, food allergies, PMS, and immune problems, as well as increase energy, lower cholesterol, and help you lose weight.
Let’s filter out these claims.
A thorn in the thistle?
Of all ingredients commonly found in these products, the herb milk thistle (Silybum marianum) is one of the more researched. Reports of its use date back to the ancient Greek physician Dioscorides, who used this white-veined plant to treat serpent bites. In Europe, milk thistle is a popular folk remedy for liver disease and is sometimes given as an intravenous drug to treat liver damage from mushroom poisoning.
Lab studies suggest that silymarin, a group of compounds extracted from the plant’s seeds, may protect the liver against damage from toxins and disease by acting as an antioxidant, immune-stimulant, and anti-inflammatory agent. It may also help stabilize membranes so toxins can’t bind and help regenerate liver cells, among other mechanisms.
While this all sounds promising, studies in people have been flawed, and results have been inconsistent or inconclusive. In a 2007 review of 13 clinical trials, the independent Cochrane Collaboration questioned the use of milk thistle for alcoholic liver disease and hepatitis B and C because of the poor quality of the research.
Moreover, nearly all studies have looked at milk thistle or silymarin in chronic liver disease; there’s little if any evidence the herb can “detoxify” or protect a healthy liver, though this is what these supplements are typically marketed for. And no matter how convenient it would be, milk thistle is not an antidote for a night of heavy drinking or for smoking, as some supplement makers suggest.
Do these ingredients deliver?
Other common “liver herbs” include licorice root extract (glycyrrhizin), Phyllanthus, and the mixture of herbs used in traditional Indian medicine called Liv-52. As with milk thistle, lab studies suggest these herbs may have some liver-protective properties. But there are no good human studies.