Supplements

The Importance of NAC (N-acetylcysteine), According to Experts

Written by Robert Iafelice, MS, RDN, LDN
Medically Reviewed by Dr. Elaine Gavalas, ND, PhD

May 1, 2024

Few nutritional supplements are more versatile than NAC, short for N-acetylcysteine. Owing primarily to its potent antioxidant and anti-inflammatory properties, NAC has been shown to help improve a wide variety of conditions ranging from neurodegenerative disorders and liver diseases to respiratory illnesses and cancer (1).

NAC is a modified form of cysteine—a sulfur-rich amino acid found in high concentrations in animal proteins (eggs, meats, seafood, and dairy products) and cruciferous vegetables (broccoli, cabbage, cauliflower). Since it is more stable than cysteine, it is preferred for use in supplement form (2).

Interestingly, N-acetylcysteine is also used intravenously in emergency medicine as an antidote for acetaminophen (Tylenol) poisoning that could otherwise lead to liver and kidney damage. Since NAC also has the ability to break down mucus, it’s an effective treatment for conditions characterized by mucus buildup (think: cystic fibrosis, bronchitis, and pneumonia) (3). Quite impressive for a natural product!

Table Of Contents

What Are the Health Benefits of NAC?

The rising popularity of NAC supplements coincides with a growing body of evidence supporting NAC supplement benefits. Here are five benefits, in particular, that you may experience.

1. Glutathione Production

While NAC is an efficient antioxidant in its own right, its ability to increase levels of a more powerful antioxidant—glutathione—plays a much greater role in its health-promoting effects (2). 

Commonly dubbed the body’s ‘master antioxidant,’ glutathione exists in every human cell, acting as the primary shield against oxidative stress caused by free radicals (the highly reactive and unstable molecules that can damage cells and cause aging and disease).

Without the protection of glutathione, vital cell components like DNA and the mitochondria, which generate energy, can suffer damage. This could eventually lead to cell death and the development of disease.

Native Note: Our glutathione levels tend to decrease with age, so it’s crucial to maintain their levels with a quality NAC supplement (4). How does NAC produce the antioxidant glutathione? Once NAC enters the body, it is first converted to the amino acid cysteine which is then used by the liver as a “building block” to construct glutathione.

2. Liver Function

Among its many functions, the liver acts as a filter to break down and remove harmful substances from your body.

Take prescription medication, for example: As the liver processes these medications, it may produce free radicals, which could potentially induce oxidative harm to the organ itself. Fortunately, NAC, which functions as an antioxidant, safeguards the liver by neutralizing these damaging free radicals that emerge from drug metabolism (5).

That being said, NAC's ability to stimulate glutathione production is particularly crucial for liver health. For instance, the commonly used painkiller acetaminophen (Tylenol) can inflict substantial liver damage, even leading to liver failure when consumed excessively or over a prolonged period.

This happens because the liver's glutathione reserves are exhausted in the process of detoxifying Tylenol. In the absence of the antioxidant protection offered by glutathione, the surge in free radical formation results in damage to liver cells. Thankfully, NAC supplementation can effectively replenish the liver's glutathione stock, making it the only clinically approved treatment for acetaminophen overdose (6).

Furthermore, studies have demonstrated that NAC supplements can nearly double (1.77x) survival rates in instances of acute liver failure that are not related to acetaminophen overdose (7, 8).

Beyond its antioxidant capabilities and role in generating glutathione, NAC can also boost blood flow and oxygen supply to the liver by escalating levels of nitric oxide (9). Nitric oxide is a powerful vasodilator, meaning it expands blood vessels to facilitate improved blood circulation.

3. Natural Detoxification

Once again, NAC’s role in increasing glutathione takes center stage …

Glutathione generated from an NAC supplement is a key player in detoxifying foreign chemicals and toxic compounds produced within your body. For example, glutathione can neutralize cancer-promoting carcinogens such as aflatoxins produced by certain molds and acrolein—a toxic chemical formed when oils are overheated (10).

4. Cellular Health

Ultimately, good health begins at the level of the individual cell. Cells that are unhealthy and not performing as they should eventually transition into a state known as "senescence," a biological stage where cells stop multiplying and their typical function diminishes.

So, instead of dying, some of these old and dysfunctional "zombie cells” continue to churn out inflammatory compounds that damage tissues and organs. The accumulation of senescent cells is a hallmark of aging and a major driver of age-related diseases such as cancer and Alzheimer’s disease (11).

Luckily, NAC has been identified as a senolytic—a compound that can remove harmful senescent cells from tissues and thus restore healthful and youthful cell functioning (12). In a cell culture study, cells from mutant mice unable to make glutathione were demonstrated to undergo premature senescence. Supplementation with NAC was subsequently shown to increase glutathione levels and prevent premature senescence in these mutant cells (13).

Moreover, in a randomized clinical trial conducted in 2023, 40 obese adults were split into two groups. The intervention group was given 600 mg of NAC daily for four weeks, while the control group was given 600 mg of placebo.

The results were impressive: Those taking NAC significantly reduced the marker of cellular senescence in adipose (fat) tissue (14). This could reduce one’s risk of age-related diseases like heart disease, Alzheimer’s, glaucoma, osteoarthritis, and more.

5. Immune Support

The COVID-19 pandemic of 2020 increased awareness of the critical importance of a strong immune defense. NAC can enhance immune responses by recalibrating an overly active immune system or rejuvenating a weak and inefficient one (15).  In fact, a review of studies (though limited) suggests that an NAC supplement could potentially reduce complications and death in patients with COVID-19 infection (16). This effect of NAC is likely due to its ability to block the replication of viruses and suppress inflammation and oxidative stress—key contributors to COVID-19 disease severity. 

NAC’s role as a potent immune booster is mostly due to its ability to restore glutathione levels in immune cells, thus protecting against infections (17). As an essential component of the immune system, glutathione shields immune cells from oxidative damage. Low levels of glutathione are associated with impaired functioning of various immune cells, inflammation, oxidative stress, and susceptibility to infections (18).

Another important function of glutathione is its unique ability to recycle and thus replenish the antioxidant forms of the vitamins C, E, and A once they are used in the body (19).  Each of these essential vitamins has important immune-boosting functions (20).

What’s the Best Type of NAC Supplement?

Glutathione is a molecule composed of three amino acids: cysteine, glycine, and glutamate. While NAC provides the cysteine component, it doesn't provide glycine.

So, even if there's plenty of NAC, without sufficient glycine, the production of glutathione could be limited. In simpler terms, for NAC to help make glutathione effectively, there also needs to be enough glycine present (21).

That said, combining glycine and NAC in a supplement could be expected to have a synergistic effect on driving greater glutathione production. Human clinical trials have reported higher levels of glutathione, resulting from a combination of NAC and glycine supplements versus each supplement alone (22). In a study in old mice, supplementation with a blend of NAC and glycine for seven weeks improved cardiac function and inflammation, whereas an NAC supplement alone did not (23).

As a bonus, glycine provides multiple health benefits of its own: improved sleep quality, collagen synthesis, anti-inflammatory activity, cell protection, antioxidant activity, neurotransmission, improved muscle health, better blood sugar control, immune support, and tissue restoration (24, 25).

So, is there a supplement that contains both NAC and glycine?

Yes—and it’s called Native NAC.

Native NAC is a new and truly unique formulation of 1,600 mg N-acetylcysteine (NAC) blended with 500 mg L-glycine as well as 500 mg L-taurine–an amino acid with promising anti-aging potential.

An overhead shot of a container of Peach Ginger Native NAC with a glass of water and a bowl of peaches and ginger

Replenish Your Glutathione: Your Body's Master Antioxidant

Native NAC combines a potent blend of amino acids into one convenient scoop to promote liver health, cellular repair, and natural detoxification.

Add to Cart

Native NAC comes in a convenient powder form with a pleasant and natural Peach Ginger flavor. It contains zero sugar and, instead, is lightly sweetened with two natural, zero-glycemic sweeteners: monk fruit and stevia. The serving size is one small scoop per day, mixed with 8 ounces of water.

Native NAC is also…

✓ Free of unnecessary fillers, GMOs, and common allergens like gluten, dairy, and soy

✓ Produced in a Certified Good Manufacturing Practices (cGMP) facility

✓ Made in the USA and third-party tested for purity and efficacy

A Note on Taurine: The health benefits of taurine include decreased DNA damage, lower inflammation, improved mitochondrial function, less anxiety, and reduced cellular senescence. Taurine levels in the body decline with age. Levels of taurine in the elderly have been found to decrease by more than 80% relative to levels in younger individuals (26).

Who Can Benefit from Supplementing With Native NAC?

As a safe and natural nutritional product with a myriad of health benefits, anyone can take Native NAC for general health maintenance and disease prevention.

Nevertheless, Native NAC may be especially useful in providing antioxidant, anti-inflammatory, and overall immune support for people with the following conditions (14):

  • Diabetes
  • Cancer
  • Neurological disease (Alzheimer’s and Parkinson’s) 
  • Cardiovascular disease
  • Inflammatory bowel disease
  • Autoimmune diseases
  • High blood pressure
  • Respiratory diseases
  • Infections

In addition, people taking multiple medications, particularly acetaminophen (Tylenol), can benefit from the increased glutathione production from Native NAC to protect the liver and enhance drug detoxification. 

Lastly, Native NAC may be used to improve brain health and athletic performance (27, 28).

How to Easily Incorporate Native NAC Into Your Routine

Take one scoop of Native NAC each day or a one half-scoop twice a day. Do not exceed the suggested dose unless recommended by a healthcare professional.

It’s best to drink Native NAC on an empty stomach between meals.

If you have trouble falling asleep, you can make the most of the sleep-enhancing effects of glycine and the calming effects of taurine. Try drinking Native NAC 30 minutes to an hour before bedtime for easier sleep.

FAQs About NAC

Yes. While providing an optimal dosage of 1,600 mg of NAC, Native NAC is also supercharged with glycine and taurine. Glycine, together with NAC, drives greater production of glutathione—the body’s most powerful antioxidant and detoxifier. Taurine provides additional antioxidant protection, particularly for the eyes, heart, and skeletal muscles. A shortage of taurine may accelerate aging.

The Bottom Line

In today’s contaminated environment, NAC can help protect your liver and improve respiratory health while also strengthening your immune defenses to fight off dangerous bacteria and viruses. By ridding the body of old but still damaging senescent cells, NAC can also delay aging. 

Native NAC is now available at NativePath. This brand-new formulation can be a valuable addition to your supplement regimen to help you combat aging and age-related diseases. 

If you have a medical condition, talk to your doctor about trying out Native NAC as an adjuvant therapy. 

Be sure to share this blog post with family and friends. With such a broad range of health benefits, Native NAC can help your loved ones improve their health and add years to their lives.

Robert Iafelice
Article by

Robert Iafelice

Robert Iafelice, MS, RD, LDN is a functional nutritionist and freelance medical writer. He is the author of Hold On to Your Muscle, Be Free of Disease, a unique perspective on wellness and disease in the context of muscle health.

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    Medical Disclaimer

    This content is for informational and educational purposes only. It is not intended to provide medical advice or to take the place of such advice or treatment from a personal physician. All readers/viewers of this content are advised to consult their doctors or qualified health professionals regarding specific health questions. Neither Dr. Chad Walding nor the publisher of this content takes responsibility for possible health consequences of any person or persons reading or following the information in this educational content. All viewers of this content, especially those taking prescription or over-the-counter medications, should consult their physicians before beginning any nutrition, supplement, or lifestyle program.

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