NAC (N-acetylcysteine): What it is, Health Benefits and How to Take it

What is N-acetylcysteine (NAC)?

N-acetylcysteine (NAC) is a stable form of L-cysteine, an amino acid used by the body to synthesize glutathione, a compound naturally present in cells.

NAC has been used for several decades in clinical settings and is also available as a dietary supplement.

How does NAC work?

After being absorbed, NAC provides cysteine to the body, an amino acid necessary for glutathione production.

Glutathione participates in various cellular processes related to redox balance and protecting cells against reactive molecules produced during normal metabolism.

What are the studied benefits of NAC?

Scientific research has evaluated NAC in various areas of health.

Published studies have investigated its potential role in:

• oxidative stress balance;
• respiratory health;
• glucose metabolism;
• male and female fertility;
• nervous system;
• immune response.

While many of these results are promising, more research is needed to confirm the effectiveness of NAC supplementation in several of these situations.

What are the dietary sources of cysteine?

Cysteine is naturally found in protein-rich foods, including:

• chicken meat;
• turkey;
• eggs;
• cheese;
• sunflower seeds;
• legumes.

Who might consider supplementation?

NAC supplementation may be considered by adults who wish to supplement their intake of this amino acid, always in accordance with their individual needs and, when appropriate, with advice from a healthcare professional.

What is the usual dosage?

Scientific studies have used doses between 600 mg and 1800 mg per day, depending on the objective studied.

The recommended dose should always adhere to the instructions on the supplement label.

Are there any side effects?

NAC is generally well tolerated when used at recommended doses.

The most frequently reported side effects include:

• nausea;
• gastrointestinal discomfort;
• diarrhoea;
• constipation.

People who use anticoagulant medications, antiplatelet agents, or blood pressure control medications should consult a healthcare professional before starting supplementation.

Pregnancy and breastfeeding

There is insufficient evidence to recommend the use of NAC supplements during pregnancy or breastfeeding without medical advice.

Conclusion

N-acetylcysteine (NAC) is a stable form of L-cysteine and has been widely studied due to its role as a precursor to glutathione.

Although research continues to explore its potential in different areas of health, the use of supplements should be part of a varied and balanced diet and a healthy lifestyle.

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