Healthy woman taking NAC for immune health

Benefits of N-Acetyl-L-Cysteine for the Immune System

Acetylcysteine, also known as N-Acetyl-L-Cysteine (or simply as NAC) has become one of the most sought-after immune support supplements. But how does it work?

To make a long story short (although, we'll get into the long story below!) NAC is an antioxidant, and more importantly, it helps your body produce the antioxidant glutathione. All of this antioxidant power benefits your immune system.

But how does an antioxidant support immune health? Like everything else antioxidants do for us, the answer lies at the cellular level.

What is N-Acetyl-L-Cysteine (NAC)?

NAC is a nutrient your body uses to create an antioxidant compound called glutathione. People take NAC as a nutritional supplement for a variety of reasons, including liver and bronchial support. One of the more exciting health benefits of NAC supplementation is immune support. But how NAC supports a healthy immune response is pretty interesting…and it's probably not what you think.

How does N-Acetyl-L-Cysteine help the immune system?

NAC helps inhibit oxidative stress which in turn helps maintain immune system function and health. That's both because it helps your body create the antioxidant glutathione, and because NAC is also a potent antioxidant in its own right: acting directly to scavenge up oxygen free radicals.

Let's talk about what that means.

What is oxidative stress?

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Oxidative stress is a byproduct of cell function (even in healthy ones). When it happens it can slow things down so that your cells don't do their jobs optimally. Here's an analogy: think of your cells as a car engine. Now think of the oxidative stress created by your cells—immune cells, heart cells, liver cells, you name it—as waste heat or exhaust: a byproduct you have to get rid of to function optimally.

Your immune cells are doing a good thing protecting your body from immune challenges. But as a result of the chemical processes that they use to power themselves, they create oxidizing free radical compounds which can make it harder to function…and this, unfortunately, is not so good.

It gets even worse in a situation in which your immune cells have to actively protect you from an immune challenge. All that hard work can produce more oxidative stress.

Which means that at the very moments when those cells need to be at their best, oxidative stress could be throwing a wrench into things. Ultimately, the less oxidative stress your cells are under, the better they'll perform.

Antioxidants and immune health

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Of course, you want those immune cells to work hard so that they can help you—without those pesky free radical compounds getting in the way of their success. So what can you do?

Enter the antioxidant.

These special chemical compounds have the superhero power of being able to "quench" those oxidizing free radical compounds, fending off oxidative stress. Thanks to antioxidants—including NAC, glutathione, and others—your immune cells can worry less about oxidative stress and more about protecting your health.

In case you were wondering, this is how one of the most "famous" immune support nutrients of all, vitamin C, supports your immune system: by quenching free radicals. Indeed, vitamin C is a powerful cellular antioxidant.

This distinction is important because we often mistakenly presume that any nutrient known to "support a healthy immune response" is either actively making your immune system stronger…or somehow rendering the immune challenges themselves weaker. But antioxidants are among the best immune health supplements, and they don't really do that: instead, they support your immune system's ability to function at the cellular level—and that can make a big difference.

Pro tip: You can find comprehensive immune antioxidant supplements that combine glutathione, its precursor cysteine, and vitamin C.

Acetylcysteine and respiratory health

NAC also has a reputation for supporting healthy respiratory function. This has to do with mucus production. While it's never going to win any popularity contests, mucus has an important job to do: it protects delicate cells such as the ones in your nose, throat, stomach and even lung tissue from foreign compounds—whether it be dust, pollen, or bona fide immune challengers. So NAC promotes mucosal health.

How? NAC helps maintain the healthy rheological properties of mucus. In layman's terms, that means it helps your body keep mucus "loose" so it's easier for you to expel it from the places you don't want it to be. NAC also encourages your body's production of secretory IgA, an antibody that is an essential part of your respiratory system's immune defenses.

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NAC and the gut connection

Your digestive system is one of the "front lines" when it comes to your immune defenses. N-Acetyl-L-Cysteine helps inhibit immune challenge activity in your digestive tract: one study found that NAC helped intestinal epithelial cells mount a healthy immune response to challenges in vitro. (In vitro means the study observed events that took place in a petri dish. This makes sense when you think about it, because observing the inner workings of your digestive tract is not easy to do!)

Do other immune support supplements work with NAC?

Woman taking an immune support supplement

As an immune support supplement, NAC generally plays well with others. Here are some nutritional supplements that can complement N-acetyl-L-cysteine's immune support benefits:

  • Zinc

    – This essential mineral is really good for your health for a variety of reasons. It supports a healthy immune response in general, and it's excellent at helping maintain respiratory health during an immune challenge. Remember our immune-health must-have mucus? Well zinc binds to the receptors of cells in your mucus membranes within your upper respiratory tract—the same ones that can be targeted by common immune challenges. Think of it like musical chairs: since that cell-receptor seat is already taken by zinc, the immune challenge has nowhere to go. (Please note: Not all zinc is the same – to get this enhanced health benefit, choose ionic zinc.)
  • Vitamin C

    – As we mentioned above, vitamin C supports your immune system in similar ways to NAC: namely functioning as a powerful antioxidant. But does more vitamin C always mean better support? No—as it turns out, your body will flush vitamin C it doesn't use. For best results, choose a slow-releasing vitamin C that stays in your system longer.
  • Vitamin D

    is another popular immune support supplement. While not an antioxidant like vitamin C, it does promote a healthy immune system, as well as bone health, cardiovascular health and more. You can add it to your regimen along with NAC and other supplements to keep your natural defenses in tip-top shape!

Of course, we always recommend that you talk to your doctor before you begin any supplement regimen.

Other ways to support NAC and immune health

Supporting a healthy immune system and complementing your NAC supplementation is really about common sense. First, get plenty of rest: your body does important work when you're asleep—so make sure to get at least 7 hours of sleep a night, more if you think you're fighting off an immune challenge. And do remember to drink plenty of water if you're taking an NAC supplement to help support your kidneys—and because staying hydrated is good for your body.

Finally, get to know how the immune system works. This complicated array of immune cells, organs and even your innermost bone tissue helps keep you safe. If you know how it functions, it will be easier for you to do your part to support it.

About the Author: John Gawley graduated from the University of Miami with a degree in English before beginning his career as a technical writer, copy writer and content manager. John has extensive experience in the health and wellness field, and he is the Senior Copywriter at Life Extension.


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