Glutathione: This ONE Antioxidant Keeps All Other Antioxidants Performing at Peak Levels
April 10, 2010
By Dr. Mercola, & Ori Hofmekler
Glutathione is your body’s most powerful antioxidant and has even been called “the master antioxidant.” It is a tripeptide found inside every single cell in your body.
Antioxidants are crucial in eliminating free radicals from your body. Free radicals are basically very reactive particles that bounce all around the cell damaging everything they touch. Most originate during the process of metabolism but they can also arise from exposure to toxins, irradiation, and toxic metals.
Because free radicals are so destructive, cells have a network of defenses designed to neutralize them. This antioxidant network is composed of numerous components that include vitamins, minerals and special chemicals called thiols (glutathione and alpha-lipoic acid).
Glutathione is comprised of three amino acids: cysteine, glutamate, and glycine.
Glutathione is sometimes confused with glutamine and glutamate due to the similarity in names. Although all three molecules are related, they are different in composition and function. When you are healthy, the three are balanced and do a delicate dance within your body.
In a nutshell, this is the difference between the three:
- Glutamine: Your body’s most abundant amino acid, made in your brain from glutamate; has a major role in various anti-injury processes and muscle repair; a precursor to glutathione.
- Glutathione (two types, GSH and GSSG): The “master antioxidant”—most powerful antioxidant in your body, present in every cell. Protects cells, and especially important for liver health; breaks down into free glutamate.
- Glutamate (aka glutamic acid or L-glutamate): Monopeptide amino acid neurotransmitter in your brain—required for synaptic activity. You don’t want too much of it—it’s an excitotoxin. (See also monosodium glutamate, or MSG)
Glutathione is different from other antioxidants in that it is intracellular. It has the unique ability of maximizing the activity of all the other antioxidants, including vitamins C and E, CoQ10, alpha lipoic acid, and the fresh veggies and fruits you (hopefully) eat every day. It removes toxins from your cells and protects you from the damaging effects of radiation, chemicals, and environmental pollutants.
You might think that a miracle molecule such as glutathione might be a good thing to put into supplement form. As usual, science loses to nature when it comes to optimizing this health-promoting little gem.
There is currently a great deal of hype about glutathione supplementation, highly popularized as a “miracle” means to boost health, prevent disease and fight aging.
Let’s separate some of the facts from the myths about how glutathione works and look at the right way to build your body’s glutathione reserves.
How Glutathione Works
The main function of glutathione is to protect your cells and mitochondria from oxidative and peroxidative damage. As you age, your body’s ability to produce glutathione decreases.
Glutathione isn’t just an endogenous antioxidant--it is also an essential factor in energy utilization, detoxification, and preventing the diseases we associate with aging. Glutathione deficiency has been linked to:
- Age-related diseases such as Alzheimer’s and Parkinson’s
- Coronary and autoimmune diseases
- Arthritis, asthma and other inflammatory conditions
- Mitochondrial dysfunction
- Muscle weakness and fatigue
Synthesis of glutathione depends upon adenosine triphosphate (ATP), which is the molecule that provides cellular energy. It follows that glutathione levels are linked to energy deficiency, or low ATP.
This is a major reason why exercise is so beneficial for your overall health—among other things, it boosts your glutathione levels!
If you can enhance internal glutathione production, you will strengthen your immune system in a way that will shield you from many of the adverse effects of aging.
Do Glutathione Supplements Work?
Your body is quite poor at getting glutathione from your digestive system into your blood. Most oral glutathione supplements have been shown to be poorly absorbed and a waste of your hard-earned money.
There has been some success with intravenous glutathione supplementation, but this is certainly not practical and very expensive and should be reserved for extreme situations. Glutathione supplementation can help people with immunodeficiency but only to a certain degree, and only temporarily—kind of like recharging a dead battery.
Ironically, glutathione supplements may actually interfere with your body’s own glutathione production.
The human body is programmed to self-produce its own antioxidant enzymes such as glutathione and SOD (superoxide dismutase, the first antioxidant mobilized by your cells for defense). And synthetic supplementation of these compounds actually signal your body to stop its own production – which leaves you dependent on synthetic substances (supplements or drugs).
Glutathione levels can be enhanced somewhat by taking supplements such as alpha lipoic acid, which is known to regenerate glutathione. Alpha lipoic acid also helps to regenerate vitamins C and E so that they remain active longer in your body. Red meat and organ meats are the best dietary source of alpha lipoic acid.
Glutamine can be used as a supplement since it’s a direct precursor to glutathione. However, there is quite a bit of evidence it is poorly absorbed.
There is also evidence that vitamin D increases intracellular glutathione. Unless you are a newcomer to my website, you know that I am an enthusiastic fan of vitamin D, and this is yet one more reason it’s so important for your health.
Some nutritional authorities recommend taking a form of cysteine known as N-acetyl-cysteine (NAC), but I would advise against using this supplement if you still have mercury amalgam fillings because it could interfere with detoxification of the mercury.
Fortunately, there are natural ways to boost your body’s glutathione reserves.
Vitamins and supplements have their uses but are always less desirable than nutrients in their natural form, obtained from the foods you eat. What has been proven beyond a doubt is that whole food based diets--rich in vegetables, fruits, nuts, seeds, and quality protein--promote health and longevity.
What Foods Promote the Highest Glutathione Levels?
Many whole foods contain significant amounts of glutathione or its precursors. Foods richest in sulfur-containing amino acids are usually the best sources of glutathione:
- The overall top food for maximizing your glutathione is high quality whey protein. It must be cold pressed whey protein derived from grass fed cows, and free of hormones, chemicals and sugar.
Quality whey provides all the key amino acids for glutathione production (cysteine, glycine and glutamate) and contains a unique cysteine residue (glutamylcysteine) that is highly bioactive in its affinity for converting to glutathione.
Glutamylcysteine is a bonded cysteine molecule (cysteine plus glutamate) that naturally occurs in Bovine Serum Albumin – a fragile immune component of the whey. This unique cysteine is exclusive to whey and rarely appears in other protein foods – which makes whey protein the best glutathione-promoting food source.
Furthermore, whey provides critical co-factors, immunoglobulins, lactoferrin and alpha Lactalbumin (also a great source of cysteine), which together help create the right metabolic environment for high glutathione activity.
- Raw milk products, raw eggs and meat: Glutathione occurs in the highest levels in fresh, uncooked meats and raw milk, but is almost entirely absent in pasteurized dairy products.
- Fresh fruits and vegetables provide excellent glutathione, but once cooked, values become negligible. Spinach, potatoes, asparagus, avocado, squash, okra, cauliflower, broccoli, walnuts, garlic and tomatoes have the highest glutathione per serving.
- The herb milk thistle is an excellent source of the antioxidant compound silymarin, which may help to prevent glutathione depletion in the liver. Glutathione is crucial in the liver for detoxification and can become depleted from acetaminophen (Tylenol), alcohol consumption, and general toxic overload.
- Curcumin may also be useful for increasing glutathione levels.
Keeping your glutathione levels up is a matter of increasing factors that boost your glutathione and decreasing factors that lower it. The things that deplete your glutathione the fastest are chemicals, toxins and sugar.
The Right Whey
If you want to supplement your diet with whey protein products, you have to be careful because not all whey protein products are created equal. Supermarket and nutrition store shelves are lined with protein powder choices, 99 percent of which are loaded with sugar and chemicals that don’t support your health goal.
If you’re going to supplement, you should only use a high quality whey protein that provides all the necessary nutritional elements for NATURALLY boosting glutathione and also preventing its decline.
Be sure your whey protein supplement has the following features:
- The whey comes from grass-fed cows that are not treated with pesticides or hormones
- Cold processed, since heat destroys whey’s fragile molecular structure
- Whey protein concentrate, not protein isolates
- Sweetened naturally, not artificially, and low in carbohydrates
- Highly digestible—look for medium chain fatty acids (MCTs), not long chain fatty acids