N-acetyl cysteine (NAC) is best known as a mucolytic, lung antioxidant and as a precursor to glutathione, an antioxidant detox agent naturally produced by the liver, but has an effect on the whole body (1,2).
NAC’s function as a mucolytic agent is supplemented with the power to take the 'burn' off of an infection.
Some of the burning sensations that are felt in respiratory infections are caused by tissue irritation and damage because of the accumulation of immune metabolites (3). These metabolites are molecules that neutralize pathogens as they are bleach-like in nature. When released, especially in high quantities, the hydrogen peroxide oxidizes tissues. Mix the hydrogen peroxide, with oxidized tissues and add to that some inflammatory metabolites, and the chest feels like it is literally burning (4).
NAC does not only come in handy in terms of thinning the mucus so that help can reach deeper into the lung tissues. Many studies show that NAC is an effective adjunctive agent in upper respiratory tract disorders. In fact, some show that there is a significant decrease in the degree of tissue damage when NAC is employed in hospital settings in cases of severe upper respiratory tract infections.
While highly efficacious for lung health NAC is much more than just a lung health agent. NAC is also an agent that is significant for brain health and mental health. How could an agent that works as a mucolytic and anti-oxidant play a role in brain health?
To simplify the concept, NAC is a detox agent and if it can detox the lung then why not the brain? But the world of medicine is not so simple (3,4).
The brain comes with a firewall known as the Blood Brain Barrier (BBB) that keeps it safe from circulating metabolites.
Evidence shows that NAC as a whole, is not able to cross the BBB.
Further research, however, shows that it can significantly alter neurotransmitter function to help with symptoms associated with brain trauma and mental health (5).
In fact, the function of NAC is strong enough to interfere with the process of fear-related memory formation, making it a very promising supplement for the treatment of Obsessive Compulsive Disorder, and Post Traumatic Stress Disorder (PTSD) (6).
Inflammatory Slime in Eastern Traditions
Prior to explaining how a mucous-thinning, detox agent can play a role at interrupting fear-based memory recall, it may be wise to explore the issue from a different point of view.
Western Medicine uses the terms “Phlegm” and “Mucous” almost exclusively for respiratory secretions.
On the other hand, Chinese medicine, Unani medicine and other eastern medicine practices use the term “Phlegm” to describe the accumulation of fluid in the body that is not successfully moved and transformed by vital energy (7,8).
The concept appears foreign, but with further reading, it appears that the concept of phlegm is related to inflammation, edema and a description of high viscosity blood that accumulates in an area of inflammation (9).
In eastern medicine, when dampness congeals because of heat it turns into phlegm.
That phlegm is a phenomenon that can affect the lung, but it can also affect different places in the body including the mind!
The origins of phlegm are in the stomach and spleen (Earth element) as they are responsible for the rotting and ripening of food (digestion).
Interestingly, the emotion associated with The Earth element is worry.
Any insult to the Earth element, can result in problems related to digestive, immune, or circulatory problems.
Some of the more common insults to the Earth element include having too much raw food, which can stress the digestive system as well as having too many sweets, and oily foods (10).
Eastern traditions recognize sweets, oily food and alcohol as damp agents that should be consumed in moderation.
Thus, it is no surprise that as early as 7000 years ago, Chinese Medicine recognized sugary foods and alcohol to be disruptors of mood and emotions.
The descriptions of damp/ phlegm clearly point to dampness as a major source of “muddy thinking.
Muddy thinking in eastern traditions is very similar to a general state of fogginess.
It focuses on the notion that the mind has a background “heaviness” that stops it from being able to process thoughts clearly.
This puts the sufferer in a state of poor memory, and general mental turbidity where they can not separate what is clear from what is turbid (10,11) .
In many ways, the eastern concept of phlegm is congruent to the concept of the accumulation of a toxic metabolite that makes information processing a heavier endeavour for the body.
Some descriptions of mental dampness and phlegm are shockingly similar to our modern day Diagnostic and Statistical Manual of Mental Disorders (DSM–5) description of Obsessive Compulsive Disorder (OCD).
Mental Illness and the Accumulation of Toxic Metabolites
Many mental illnesses have been linked to the accumulation of toxic metabolites in the brain.
Dr. Abraham Hoffer, was famous for employing orthomolecular agents for the treatment of mental illness.
In fact, as the founder of the “adrenochrome’ theory, he was one of the pioneers who used high dose nutraceuticals as moderate to severe mental illness treatment agents.
His research looked mainly at the role of mega doses on niacin in helping detoxify the brains of schizophrenia sufferers (11).
While some disagree with his concepts, significant findings that supported his theories were often found.
NAC for Mental Health
More current research in NAC shows that NAC plays a significant role in improving the overall quality of life of schizophrenia sufferers as a safe, tolerable adjunctive agent.
Additionally, it shows promising results for OCD and depressive disorders.
While some theories point towards NAC being a regulator of glutamine levels, others point to its ability to function as an anti-inflammatory as there appears to be theories of inflammation being the cause or at least having an association with mental illness (14).
NAC for OCD and Recurring Fears
Clinical studies demonstrate the role of the neurotransmitter glutamine in the pathophysiology of OCD.
Modern science appears to progress towards classifying OCD as an abnormality in the cortico-striato-thalamic- cortical circuit (CSTC).
The CSTC is a brain pathway that contains glutamate as the primary neurotransmitter (15,16) .
Higher levels of glutamate were found in the cerebral spinal fluid in patients with refractory OCD.
Theories about the abnormal regulation of glutamate levels appear to prevail in the world of neuropsychology.
It is no shock that OCD appears to respond to glutamate modulators as glutamate is a neurotransmitter that is known to be involved in memory formation (17).
Modulators of glutamate appear to function both as single treatment agents and also as adjunctive agents in the treatment of resistant OCD (17,18).
What is even more intriguing is that NAC shows promising evidence as an adjunctive agent for the treatment of refractory Post Traumatic Stress Disorder (PTSD), adding more to the credibility of the theory that NAC may be successful at assisting with the amelioration of fear-based memory.
As glutamate reaches higher than normal levels, it leads to a higher excitatory load on cells resulting in excitotoxicity and oxidative stress .
The oxidative stress was detected in the serum of OCD patients as a form of lipid peroxidation.
Interestingly, the level of oxidative stress is directly linked to symptom severity(19)!
Glutamate has a direct function in cognition, decision making and fear- related memory (17).
Though reports of cystine being able to cross the BBB are contradictory,
It appears that 12- week use of a dose of up to 3000 mg of NAC/ day significantly reduced OCD symptoms and had excellent safety and tolerability.
Most theories point towards the functionality of NAC as an in-direct neurotransmitter modulation agent (17).
When East Meets West
The explanation for the function of NAC as an agent for mental health support can be seen from both the Eastern Medicine lense as well as the Western Medicine lens.
It appears that both systems view NAC as a “sweeping agent” that clears the mess and makes cognition clearer.
The aim of this article was to demonstrate that the wisdom of different systems of medicine is congruent.
The challenge comes in deciphering the code that is encrypted in a language used thousands of kilometers away and often also thousands of years in the past.
Having the willingness to examine our new medicines using the ancient systems may give us a tool to understand concepts in a multidimensional point of view.
Eastern medicine concepts easily explain the multi-functionality of agents as it views the body from a more holistic perspective.
Thus, as an agent that sweeps away dampness, science demonstrates that NAC is efficacious for:
- Cystic fibrosis
- PCOS (female conditions)
- High cholesterol
- Blood Pressure
- Bipolar disorder
- Nerve trauma
- General Detox
- Post Alcohol consumption
- Male fertility
- Kidney Injury
- Dry eyes
- + Much more
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