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.
The same goes for the other herbs (such as dandelion, artichoke, and sea buckthorn), amino acids, vitamins (such as B12 and E), and other substances (such as choline, inositol, and chlorophyll) that may be found in liver supplements. Some ingredients may have dangerous side effects. For example, unless licorice is specially processed to remove a particular compound, it can raise blood pressure.
The best way to protect your liver is to:
- Avoid heavy alcohol use, a major cause of cirrhosis and other liver damage.
- Heed dosing directions for acetaminophen (Tylenol or generics, also in many other over the counter products). The maximum dose for acetaminophen is four grams (eight extra-strength tablets) a day for a limited time, and less if you drink alcohol or take certain prescription drugs. Acetaminophen with alcohol is particularly risky.
- Watch your weight. Obesity increases the risk of nonalcoholic fatty liver disease.
- When working with toxic chemicals—such as some cleaning solutions, paints, and pesticides—ventilate the room and/or wear a mask.
- Be wary of supplements. Rather than cure liver problems, some are potentially toxic to the liver—notably chaparral, comfrey, mistletoe, and very high doses of certain vitamins.
- Talk to your doctor about getting vaccinated against hepatitis A (spread via contaminated food, water, and feces) and hepatitis B (spread via direct blood contact, sexual intercourse, and sharing of contaminated needles). It may be advised if you are at risk. Though there is no vaccine against hepatitis C (spread primarily via blood), you should get tested for it if you had a blood transfusion before 1992 or have used unsterile needles.
Bottom line:Avoid “liver support” supplements. Just because a healthy liver helps detoxify your body, that doesn’t mean it needs to be detoxified itself. It is not like a clogged filter. And a healthy liver has a remarkable ability to restore itself when damaged. If you have liver disease, never take any supplement or medication without consulting your doctor.