Glutathione: What You Should Know

Medically Reviewed by Zilpah Sheikh, MD on March 23, 2024
Written by Eric Metcalf, MPH, Julie Marks
5 min read

Your cells contain glutathione, which is a substance made from three amino acids: cysteine, glutamate, and glycine.

Glutathione acts as an important antioxidant in your body. That means it helps combat free radicals, molecules that can damage your body's cells.

Glutathione plays a role in many chemical reactions in your body. It also helps detoxify chemicals, including some that your body creates naturally, as well as pollutants and drugs.

Your supply of glutathione seems to drop as you get older, possibly because your body can't create as much. Lower glutathione levels seem to go hand-in-hand with poorer health. For instance, lower levels may play a role in many conditions that are more likely to develop in older people.

Your glutathione levels may also fall if you have certain conditions, such as:

Glutathione vs.N-acetyl cysteine

N-acetyl cysteine (NAC) is a form of cysteine, which is an amino acid. NAC may help ease the side effects of certain drugs and chemicals. It also helps break down mucus in your body. Some people take NAC as a supplement to help treat respiratory problems, heart issues, or other conditions.

NAC is a byproduct of glutathione. Along with glutamine and glycine, it helps make and replenish glutathione. You can take NAC to help boost glutathione levels in your body. Some research suggests that NAC may increase glutathione more effectively than standard glutathione supplements.

If you don’t have enough glutathione in your body, you might notice symptoms such as:

  • Fatigue
  • Brain fog
  • Sleep problems
  • Frequent infections
  • Anemia (low red blood cell count)
  • Loss of coordination
  • Seizures

Some people take glutathione:

  • For its antioxidant benefit
  • As a detoxification agent
  • To try to protect themselves from the harmful effects of radiation and chemotherapy for cancer (there is no evidence that glutathione works in this regard)

People also take glutathione to try to boost weakened immune systems and help with infertility and many other conditions.

It may not be effective to take glutathione by mouth, as it is thought that glutathione may be broken down by enzymes in the stomach.

Some studies are looking at glutathione's health effects when it's taken by injection or inhaled directly into the lungs.

Certain supplements may boost your body's production of glutathione, such as:

Glutathione for skin

Some people use injectable glutathione to lighten their skin or hide dark spots. But there is very limited evidence that glutathione can change skin pigment. What’s more, the FDA in the Philippines, where the practice is popular, warns that injectable glutathione for your skin may be unsafe. The agency says it can have toxic effects on the kidneys, liver, and nervous system.

Glutathione for liver

Glutathione is thought to flush out toxins in the liver. It may also protect your liver from damage.

One small study found that people with nonalcoholic fatty liver disease who took glutathione by mouth for 4 months had improved liver enzyme markers. Other research has shown people with liver disease who received high doses of glutathione via an IV had improvements in their liver function tests.

Glutathione and weight loss

Some research suggests that glutathione may help with weight loss. One study found people with obesity who had higher levels of glutathione lost more weight when they followed a healthy eating plan for 6 months.

Your body doesn't seem to absorb glutathione well from foods. But certain foods high in amino acids that contain sulfur may help boost your levels. These include:

  • Unprocessed meat
  • Garlic
  • Broccoli
  • Asparagus
  • Avocados
  • Spinach

There’s no standard dosage for oral glutathione. In most studies, people take daily amounts in the range of 250-1,000 milligrams.

Oral glutathione is controversial in the medical community. Some research suggests your body may not effectively use the pill. But other studies have found glutathione taken by mouth may raise glutathione levels in your body. A special form of the supplement, called liposomal glutathione, may be more effective than standard glutathione.

Your body might absorb sublingual glutathione better. This form dissolves under your tongue. In some studies, people take 100 milligrams of sublingual glutathione twice a day.

You can also take glutathione via inhalation or injection.

Side effects. Taking glutathione long-term has been linked to lower zinc levels. Inhaled glutathione may trigger asthma attacks in people who have asthma. Symptoms may include wheezing.

Risks. Avoid taking glutathione if you're sensitive to it. Experts don't know if taking glutathione is safe during pregnancy and breastfeeding.

Interactions. Tell your doctor about any supplements you're taking, even if they're natural. That way, your doctor can check on any potential side effects or interactions with any medications.

Supplements are not regulated by the FDA in the same way that drugs are. The FDA does not review these supplements for safety or efficacy before they hit the market.

Some things can affect how glutathione works in your body. It might be best to avoid:

  • Alcohol
  • Smoking
  • Caffeine
  • Medications, such as acetaminophen (Tylenol) and aspirin
  • Too much dairy
  • Processed or fried foods

If you stop taking glutathione, your body might not provide as much immune support or antioxidant protection.

Glutathione is an important antioxidant that may help protect your body from a variety of diseases. You can get glutathione via foods or supplements. It’s a good idea to talk to your doctor before starting a new supplement, such as glutathione.

What is glutathione best for?

Glutathione is best known for repairing damaged cells in your body. It may help ward off a variety of diseases, such as neurological disorders, liver disease, certain heart conditions, autoimmune disorders, respiratory diseases, and other medical conditions.

Is it OK to take glutathione every day?

It’s best to ask your doctor if you can take glutathione every day.

What food is highest in glutathione?

Generally, fruits, vegetables, nuts, seeds, and lean proteins contain a lot of glutathione. Processed foods tend to have low levels of glutathione.