(225) 784 - 2168 cathy@cathysmithndlmt.com

Today’s blog is about N-acetyl-L-cysteine.  That’s a bit of a mouthful, so we just refer to this amino acid as NAC.


Now, before getting into the particulars of what NAC is, where it comes from and what it can do for you, here’s the standard disclaimer about supplements:

No supplement should be taken without spending time researching why it is necessary for your well-being, why you may be experiencing a deficiency, and what sort of conflicts it may have with other nutrients and especially prescription and over-the-counter medications you’re taking.  There’s a world of information available about all of these things, and to be blunt there’s no excuse for not figuring all of this out before you pop the first pill or capsule.  

Another Important Warning:

if in your research you read “consult your doctor before starting any supplement” please pay attention.  Remember that we live in a complex world in which are all sorts of illnesses, syndromes and disorders, not a single one of which does not have some standard treatment protocol (even the ones that are not fully understood, which are quite a few).

Okay, let’s talk about NAC.

First of all, NAC is an altered form of the naturally occurring amino acid L-cysteine, which is a non-essential amino acid our bodies can make from methionine (essential and therefore diet-sourced) and serine (non-essential).  We can also get cysteine from protein-containing foods such as meats, eggs, seeds, and cheeses.  This may cause you to ask the obvious question: if I can get cysteine from so many sources, and can even make it myself, why would I ever need NAC?  That’s a very good question, and it’s really the first question we should ask about any supplement.

In a nutshell, we supplement for one or more of a few reasons:

  1. insufficient nutrient intake
  2. inadequate absorption of the nutrients we take in
  3. unusual circumstances demanding additional nutrients beyond what we’re able to take in, digest and absorb.   

Let’s expand on these 3 points  

  • We take in insufficient nutrition when we eat nutrient-deficient foods, which unfortunately are all around us in modern life.
  • We absorb nutrition less well as we age, due primarily to insufficient hydrochloric acid production in the stomach and/or inadequate pancreatic enzyme production. 
  • In the case of illness or injury, or even normal aging (this means aging while consuming the Standard American Diet) the demand for nutrition increases; in the last case, as you age your body’s demand for nutrition increases while your ability to digest and absorb the nutrition you’re consuming decreases – you can’t win this one without dramatically changing your lifestyle. 

So what does NAC do for us? 

Here is a short list of issues that can benefit from supplementation with NAC: kidney and liver toxicity; brain function; fertility; blood sugar; respiratory health; immune function; skin disorders.

How does NAC work? 

Think glutathione.  Otherwise known to biochemists as gamma-glutamylcysteinylglycine or the much-simpler GSH, this is the most abundant antioxidant in the body.  Anytime you read about something that is the most abundant anything in your body, pay attention!  Yes, we have lots of it naturally and this is the way God intended and He certainly provides.  But deficiencies can quickly cause problems.  Think in terms of water.  Water is the most abundant material in our body, meaning we have lots of it.  Yet a deficiency of just a few percent of this very abundant material puts us in a state of dehydration.  Who among us doesn’t know about drinking enough water, right?

So, increasing or maintaining the level of the antioxidant GSH is vital to our health.  If you have undergone a thorough evaluation of your health status and there are obvious issues related to oxidative stress, then it makes sense to address a potential GSH deficiency.  This is where supplementation with NAC can help.

Now, you might ask why not take GSH (glutathione) instead of NAC if you need additional glutathione?  For most purposes, the answer would be to just take GSH.  However, GSH cannot cross the blood-brain barrier, and it turns out that the brain is the organ most susceptible to oxidative damage.  Given enough time, this oxidative damage can lead to cognitive disorders including Alzheimer’s and Parkinson’s, and various mood disorders as well.  So keeping our antioxidant level in the brain as high as possible has to be a priority for all of us.  And NAC can do this. 

The key takeaway from this blog should be two-fold: first, don’t assume that you’re about to keel over because you lack sufficient GSH.  You don’t know if you’re deficient unless you consider all of the potential symptoms of deficiency and rule out other potential causes.  A natural health practitioner can help with this.  Second, NAC is almost certainly not going to be the sole corrective supplement recommended by anyone.  Again, you should have a practitioner do a thorough evaluation of your overall state of health, and put together a plan to address issues in the most effective way. 

But perhaps most importantly, if this plan does not include an evaluation of your eating habits and nutritional intake, with recommendations if needed, find another practitioner.

If you have questions about NAC specifically, feel free to contact Cathy or me by completing the Contact Form at the bottom of this page.

If you’ve been thinking about some health issues you’d like to tackle using nutrition and possibly supplementation, just click on this link. You’ll be taken to a page where you can purchase a $129 Nutritional Assessment so you can enjoy:


  • a one-on-one health consultation with Cathy
  • better insight into your current situation and how you got here,
  • supplementation suggestions,  and
  • an opportunity to begin the process of addressing bothersome issues such as aches, pains, headaches, being foggy-headed (and a whole slew of other issues).


Contact Cathy

(225) 784 – 2168

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