What does NAC help with? Learn about its properties, uses and dosage.

N-Acetyl-L-Cysteine, known as ‘NAC’ for short, is a special form of the well-known amino acid L-cysteine. NAC is said to have various health-promoting and antioxidant effects, making it successful in supporting lung and liver health. L-cysteine is an important building block of a healthy immune system, and is also involved in the transmission of information to the brain. So what is worth knowing about NAC, and why should you start using it?

NAC – what is it?

NAC (N-Acetyl-L-Cysteine or N-acetylcysteine) is a derivative of the amino acid L-cysteine – a synthetic compound that does not occur naturally and is not supplied with food. Once in the body, NAC is rapidly converted into cysteine, an amino acid that the body can successfully synthesise.

NAC plays an important role in various metabolic processes, such as fatty acid synthesis and hormone production. It is also essential for the production of glutathione, considered to be the body's most important antioxidant.

NAC was first discovered in 1899, but its chemical and industrial synthesis and pharmaceutical use did not begin until 1960. Around the 1990s, after the success of many clinical trials was reported in the media, its health benefits were demonstrated. NAC began to be used as a supplement in various therapeutic areas. Currently, this compound is recognised by the scientific community and is the subject of numerous studies and clinical analyses.

What are the properties and effects of NAC?

N-acetylcysteine is an important substance for the human body. NAC is a powerful antioxidant (it has antioxidant properties), helps fight oxidative stress by supporting the synthesis of glutathione - one of the most powerful antioxidants - and maintaining sufficient levels of it in the body. In addition, it also has anti-inflammatory properties, which gives it clear therapeutic significance.

In addition to the above, NAC has the following properties:

• Detoxifying – supports cell detoxification, helps in cases of peptide or alcohol poisoning, paracetamol overdose and consumption of mushrooms of the Amanita genus (fly agaric).

• Expectorant – dissolves mucus in the respiratory tract, reduces the symptoms of chronic asthma and bronchitis, and is also helpful in respiratory tract infections in children.

• Hepatoprotective – reduces liver damage, protects the organ from alcohol and environmental pollutants.

• Antioxidant – increases glutathione levels and protects cells and organs from oxidative stress.

• Antiviral – protects against and reduces the risk of influenza infection. NAC is also a helpful ingredient in the treatment of sinusitis and respiratory tract infections;

• Improves athletic performance – increases muscle regeneration, improves strength and endurance, promotes accelerated muscle regeneration and increases blood flow to muscles in people with sedentary lifestyles.

• Cardioprotective – accelerates recovery in patients after a heart attack. Prevents damage caused by oxidative stress.

• Dermatological – reduces mild to moderate acne, treats certain skin conditions such as scleroderma ulcers and dermatitis.

• Analgesic and anti-inflammatory – relieves pain and reduces markers of inflammation.

• Antidiabetic – reduces insulin resistance, restores normal glutathione levels, which are low in diabetics.

• Improves intestinal peristalsis – relieves symptoms of gastric reflux, limits the growth of bacteria in the small intestine and reduces colitis.

N-acetylcysteine in food – where can it be found?

None of the foods, both animal and plant-based, that we consume on a daily basis provide N-acetylcysteine. Only L-cysteine (i.e. acetylcysteine) is supplied with food. Its main sources are soybeans, beef, sunflower seeds and oats.

N-acetylcysteine is formed as a result of the acetylation of L-cysteine. This is a reaction involving the attachment of an amino acid to an acetyl group (COCH3). This modification can occur naturally in the body thanks to the intervention of specific enzymes called acetyl transferases. This reaction is a post-translational modification that most proteins undergo. N-acetylcysteine has the advantage of being more easily absorbed by the body.

How does NAC affect the human body?

The power of N-acetyl-L-cysteine lies in its versatility. It has a unique ability among chemical substances to act at various levels of the body, mainly exhibiting preventive and protective effects. What exactly are the effects and health benefits offered by NAC?

• Beneficial for lung health – NAC is a commonly prescribed molecule throughout Europe for the treatment of chronic bronchitis. It is credited with mucolytic properties that improve breathing and facilitate the expulsion of secretions in patients. The molecule also shows some effectiveness in most cases of chronic obstructive pulmonary disease.
• Anti-inflammatory effect – inflammation is a defence system created by the body in cells and tissues. The defence reaction causes significant heating, dilation of capillaries and a high concentration of immune cells such as cytokines and leukocytes. NAC reduces the level of pro-inflammatory cytokines, leukocytes and interleukins. It also acts against other regulators of immune responses.
• Supports the hepatic system – N-acetylcysteine has anti-inflammatory and antioxidant properties that affect most of our organs, including the liver. It acts on liver cells by increasing glutathione levels, of which our liver is the main user due to its detoxifying role in the body. Long-term NAC supplementation reduces tissue damage caused by liver pathologies such as fatty liver disease or hepatitis B.
• Cardioprotective effect – NAC, thanks to its antioxidant properties, is also a beneficial supplement for heart health. Studies show that the molecule does indeed allow for faster recovery after a heart attack. People with diabetes benefit from additional protection against oxidative stress and the damage it causes to the heart muscle.
• Promotes improved physical performance – physical exertion and sport cause increased production of free radicals in the body. Consuming NAC becomes interesting when the production of free radicals exceeds the neutralisation capacity of our endogenous antioxidant system. In other words, NAC helps to increase the body's ability to neutralise free radicals.
  

Scientific opinions – is it worth using NAC supplements?

Clinical studies on NAC have mostly focused on the mucolytic effect of the molecule. Many scientists are positive about its effectiveness in treating respiratory and lung diseases, including bronchitis.

On the other hand, due to its ability to clear the airways and be a precursor to glutathione, scientists have successfully observed the positive effect of NAC on the overall improvement of health and immunity. The most significant results of N-acetylcysteine have been observed in elderly people and children with cystic fibrosis.

NAC supplements and alcohol – what you need to know?

N-acetylcysteine (NAC) and acetylcysteine are successfully used in the treatment and prevention of the destructive effects of alcohol on the liver. What is more, recent scientific studies are also focusing on the potential impact of N-acetylcysteine in the treatment of neuropsychiatric disorders such as alcohol addiction.

However, it should be noted that although this amino acid derivative protects the liver from the destructive effects of alcohol, chemicals and drugs, it should be avoided after recent alcohol consumption. One scientific publication clearly stated that acetylcysteine administered within 4 hours of consumption of alcoholic beverages exacerbated liver damage in laboratory mice.

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