Glutathione is a powerful antioxidant that’s found naturally in a wide variety of plants and animals.
It’s a popular supplement among people looking for advanced antioxidant capabilities, especially when combined with other advanced antioxidant supplements like NAC and ALA.
Our research team has summarized the latest science on glutathione. Read on for more.
1. Glutathione can fight oxidative damage
Scientifically, there is strong support for its use as an agent to combat oxidative damage in the body, whether that’s from disease or more mundane sources like exercise.
As you might expect given its versatile function, there are a wide range of potential benefits that you can gain from a glutathione supplement.
2. Glutathione can help maintain a healthy immune system
One of the myriad challenges of getting older is a deterioration in the capabilities of your body’s immune system.
There is evidence that glutathione could help battle back against this decline, possibly because of its antioxidant activities. A scientific paper published in the journal Mechanisms of Ageing and Development investigated the effects of glutathione supplementation in both young and old mice (1).
The researchers found that administering a glutathione supplement to older mice made their immune system stronger and more similar to that of the younger mice.
Specifically, the glutathione supplement was associated with an improvement in T-cell responses in the older mice, which is a good metric for evaluating how well your immune system can fight back against infection.
3. Glutathione can reduce the oxidative stress on your body caused by exercise
One necessary consequence of exercise is an increase in oxidative stress, due to the simple fact that your body goes through a lot more oxygen in a short amount of time when you are exercising at a high intensity.
One problem with this is that it causes a lot of oxidative damage to the cells of your body, and although this doesn’t offset the health benefits of exercise, it’s still not ideal.
Research published in the Journal of the International Society of Sports Nutrition discusses the potential role of glutathione in reducing this oxidative damage (2).
According to the authors, glutathione can prevent oxidation of lipid membranes on the outside of cells in the body, and as a result, could lead to both improved performance and better health.
4. Glutathione could help combat chronic fatigue syndrome
A small but growing number of people with chronic fatigue syndrome are claiming impressive benefits thanks to supplemental use of glutathione.
While no clinical trials have evaluated the benefits of glutathione for chronic fatigue syndrome, some interesting evidence suggests a possible mechanism that could explain this effect.
A scientific paper published in 2014 investigated how chronic fatigue syndrome was related to oxidative stress, and cited glutathione levels as a potential explanatory factor (3).
In the paper, the scientists used neuroimaging techniques to examine the levels of glutathione along with other antioxidants in the cortical area of the brain in patients with chronic fatigue syndrome.
They found that decreases in glutathione were associated with ventricular lactate levels, a biomarker for fatigue.
5. It might be more effective to combine glutathione with NAC and ALA
So far, the biggest clinical trial of glutathione was conducted by researchers at the University of Washington (4).
Their study used 40 adult volunteers, split into two groups. One group took 500 mg of glutathione twice per day, while the other was given a placebo. After four weeks, the researchers did not find any differences in antioxidant status between the two groups.
Some supplements combine glutathione with ALA or NAC in an attempt to address this problem, so if you aren’t getting results with glutathione by itself, you might want to try a combined-antioxidant supplement instead.
6. Glutathione may help reduce gastrointestinal inflammation
New research published in the journal Scientific Reports suggests that glutathione might be able to combat the problems associated with helicobacter bacteria, a common and harmful type of gut bacteria (5).
The study used an animal model to show that oral supplementation with glutathione was able to reduce inflammation in the stomach and slow the proliferation of helicobacter bacteria.
Glutathione may eventually be considered as a prebiotic supplement, and this mechanism may help explain its apparent outsized impact on immune system function.
Glutathione side effects
Glutathione might cause gas, loose stools, and flushion. In the largest and most comprehensive clinical trial of glutathione use, the only side effects reported were increased gas, loose stools, and flushing (6).
Glutathione does not seem to affect organ function. This study also took the extra step of taking blood samples to test for biomarkers of organ function, and found no disturbance in normal healthy functioning in any of the patients as a result of the glutathione supplement.
Glutathione’s GI side effects are similar to those caused by sulfur-rich foods. The lack of major side effects might be because glutathione is naturally produced in your body when you consume foods rich in the sulfur-based amino acids, such as broccoli, kale, and cabbage.
Aim for 500 mg per day or more. The biggest study to date used a dose of 500 mg twice per day, but did not find that this produced a significant increase in antioxidant status.
It may be that glutathione needs to be combined with other antioxidant-boosting ingredients like n-acetyl-cysteine or alpha-lipoic acid to be effective. Going with a higher dose than this is a little risky, because studies haven’t evaluated higher doses for their side effect profiles.
Glutathione benefits FAQ
Q: What are the symptoms of glutathione deficiency?
A: Glutathione deficiency is a serious medical problem, and is associated with anemia, loss of coordination, and muscle stiffness, among other symptoms.
Deficiency in glutathione is usually caused by a genetic mutation, so in these cases, supplementation is typically not helpful.
Lower, but still biologically normal, levels of glutathione don’t have a well-characterized symptom set.
Q: What foods are high in glutathione?
A: Glutathione is present in high concentrations in whey protein, grass-fed beef, and eggs, as well as in healthy plant sources like broccoli, cauliflower, and black mustard seed.
Since glutathione is built from amino acids, and is reliant on the presence of sulfur for its chemical structure, foods like broccoli and cauliflower that have sulfur-containing nutrients and amino acids are an excellent way to get high levels of glutathione through natural foods.
Q: What does glutathione do?
A: Glutathione is a powerful antioxidant that protects your body’s cells from reactive oxygen species. This oxidative damage can cause inflammation, which is in turn associated with risk factors for chronic disease, not to mention aging and decreased immune function.
Experimental research suggests that glutathione may help maintain the ability of your immune system to fight off infections, limit the inflammation caused by harmful bacteria in your stomach, and reduce the amount of oxidative damage your body sustains.
Q: How can you boost glutathione?
A: Actually increasing glutathione is tricky; not all of the evidence suggests a plain glutathione supplement will do the trick.
On one hand, animal research suggests that some of the immediate and direct benefits of glutathione can be had by a normal glutathione supplement.
These include suppressing the proliferation of harmful bacteria in your intestines, as well as reducing inflammation in your gastrointestinal tract and potentially reducing the symptoms associated with chronic fatigue syndrome.
However, actually raising blood levels of glutathione (and presumably reaping the antioxidant benefits that are associated with this increase) has proven to be more difficult.
Taking glutathione alongside NAC and ALA might help boost the bioavailability of glutathione.
Related: Our best glutathione picks
Glutathione is an advanced antioxidant supplement that’s most popular among people looking to combat oxidative damage, reduce inflammation, boost their immune system, or fight the symptoms of chronic fatigue.
Emerging evidence suggests that glutathione may work best when combined with other antioxidants like NAC and ALA, though to date, clinical trials in humans have focused on glutathione alone.