N-acetyl Cysteine: A Multi-Faceted Antioxidant

A powerful supplement you may want to include in your daily life
a hand holding white pills
Pexels / Artem Podrez

N-acetyl cysteine (NAC) is a potent antioxidant with anti-inflammatory and immune-mediating effects. It comes from amino acids—the building blocks of protein. Its uses are vast, well researched, and it’s one of my favourite supplements! 


The main function of NAC is to act as an antioxidant which removes free radicals. Free radicals cause inflammation, damage to your cells and DNA, and speed up aging. They are created in the body by many everyday factors such as pollution; tobacco smoke; alcohol; industrial chemicals; processed, deep-fried, and sugary foods; pesticides; certain drugs; and radiation. These unstable molecules are known to cause inflammatory diseases (e.g., arthritis, autoimmune diseases), neurodegenerative diseases (e.g., Alzheimer’s), cardiovascular disease, and cancer. 

Factoid: NAC is an approved drug in both Canada and the US. It’s used for many things, including acetaminophen overdose!


We can’t talk about NAC without learning a little about glutathione. Glutathione is an antioxidant as well and is created in the liver. NAC helps to increase the production of glutathione—which also reduces free radicals and helps to improve liver detoxification.


Our lungs are exposed to pollutants daily. Tobacco smoke, pollution, chemicals, viruses, and bacteria all affect and can cause disease in the lungs. Thankfully, NAC and glutathione, being antioxidants, help prevent and reverse the damage caused by these pollutants.

Additionally, NAC acts like a mucolytic (i.e., an agent that makes mucous less sticky so it’s easier to remove). In the case of lung health, NAC is often used for chronic bronchitis. If you have chronic bronchitis, you know how difficult it can be to cough up the mucous that builds up in your lungs; NAC thins this out to make it easier to cough up. Similarly, NAC can be helpful for cystic fibrosis as well. 


Hormones are the chemical messengers that regulate our bodies. Hormones control our metabolism, menstrual cycles, fertility, appetite, and growth, among other bodily functions. Ideally, our hormones are all working in synergy for optimal functioning; but unfortunately, in real life, millions of people worldwide suffer from hormonal diseases and disorders.

NAC May Be Able to Help


The main contributing factors in polycystic ovary syndrome (PCOS) are insulin resistance, high androgens, and irregular menstrual cycles. High insulin can lead to weight gain/difficulty losing weight, acne (especially cystic), and inhibition of ovulation. High androgens can also be associated with cystic acne.

A note on ovulation: We can tell we are ovulating by paying attention to our bodies. There can be changes to vaginal discharge (e.g., sticky, egg white consistency), breast tenderness, increased sex drive, and an increase in basal body temperature. Alternatively, we can tell by using ovulation test kits or measuring our hormones. Ovulation is not only necessary for making babies, but is also a marker of good health; it improves your mood, energy, and memory. 

NAC is used in PCOS for improving pretty much all of these contributing factors. It improves ovulation, insulin sensitivity, and decreases androgens. Can NAC control PCOS all on its own? No, probably not. However, it can work well adjunctively to a well-rounded treatment plan. 


man giving woman in bed a white pill to take
Photo by Pavel Danilyuk from Pexels



Endometriosis is more common than most people realize—it affects one in ten women and is commonly overlooked. It’s characterized by heavy, painful periods. At its worst, it can cause intense chronic pain throughout your cycle (not just on your period) and can be debilitating. Endometriosis occurs when endometrial tissue (i.e., the tissue that lines your uterus and is shed during your period) grows outside of the uterus. It can be on the uterus, ovaries, fallopian tubes, in your bowels, and even on your kidneys. I could talk about endometriosis all day, but let’s focus on NAC’s role. NAC reduces the size of endometrial lesions, prevents the growth of this tissue, and as a result, reduces pain and severity. NAC can even help these patients get pregnant!1 


Conception is controlled by hormones—specifically, luteinizing hormone (LH), follicle-stimulating hormone (FSH), estrogen, and progesterone. Egg health is an important factor in fertility, to say the least, and NAC is proven to improve egg quality and prevent miscarriage.2 

Factoid: NAC is safe in pregnancy! Your health care provider might recommend NAC for preventing miscarriage, reducing inflammation, hypertension, and regulating insulin.


If you have Hashimoto’s thyroiditis or Grave’s disease, chances are your thyroid antibodies are high, and your glutathione is reduced. If you haven’t had these checked, it might be a good idea to do so. An increase in glutathione—which occurs by taking NAC—actually reduces thyroid antibodies, which in turn improves your thyroid-stimulating hormone (TSH) levels. The best part is that NAC is safe to take alongside most thyroid medications. 


This brings us back to insulin resistance—specifically, type 2 diabetes, where insulin becomes unresponsive to changes in blood sugar. As mentioned earlier when we learned about PCOS, NAC improves insulin sensitivity. It works best preventatively, so if you are at risk for developing type 2 diabetes, this could be helpful as a part of your treatment plan. 


In those taking drugs that burden the liver, NAC can be protective by increasing glutathione to improve liver detoxification (as mentioned earlier). NAC can also improve fatty liver and improve outcomes in liver failure.3 

Cold and Flu Fighter

NAC improves our immune system; it can suppress viral replication, which is necessary for viruses to infect us. Research shows that it also reduces the length and severity of colds/flu by thinning out the mucous that contributes to a wet cough and stuffy nose.4

Mental Health 

NAC can even be used to help some mental health conditions, not only due to its anti-inflammatory effects, but also because it increases glutamate, a neurotransmitter.5 This supplement can be useful for OCD, schizophrenia, and bipolar disorders. 

Side effects

What’s fantastic is that NAC comes with very few side effects. It does smell like sulphur (which can be unpleasant), and can cause nausea, vomiting, skin rashes, or diarrhea, but these side effects are uncommon. 

Sounds like the best supplement in the world, doesn’t it? This multi-faceted supplement can help millions of people, if used correctly. If you have any of these conditions, ask your health care provider if NAC might be right for you! Dosing, brand, and length of treatment matter, and certain people should not take NAC.

Always remember to consult your health care provider prior to using this. Your health outcomes should be monitored by someone who is trained in utilizing supplements. 


For references visit ecoparent.ca/TWF/LATESUMMER22 


You May Also Like: Curcumin is an Antioxidant, Free-Radical Fighting Superstar, Choosing the Right Supplement for You, Synbiotics: The Best of Both Worlds.


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