N-acetyl cysteine (NAC), a form of cysteine, is an amino acid that can become essential when you are deficient in the essential amino acids methionine and serine. Your body needs cysteine to produce glutathione, but this amino acid is only considered to be semi-essential since it is usually synthesised in your tissues using serine and methionine.
Glutathione is considered to be your body’s most powerful antioxidant, so obtaining cysteine from NAC or another source is absolutely essential to your health. In addition to facilitating the potent effects of glutathione, NAC may also directly improve your neurological health, help with detoxification, improve respiratory function, boost immunity, promote sexual health, and provide additional benefits.
NAC is highly soluble in water. In fact, this substance is considered to be even more water-soluble than L-cysteine, another popular form of cysteine.
L-cysteine, the natural form of this amino acid, is found in various high-protein foods, such as meat, dairy, and legumes. NAC, however, is a modified form of L-cysteine, so it is not found in any food sources.
Major regulatory agencies do not recognise NAC as an essential nutrient, so there is no official daily dose or nutrient reference value (NRV) for this substance. In clinical studies, however, this modified amino acid is often administered in concentrations of 0.5-1g per day.
NAC, the modified form of L-cysteine, is not available in any food sources, so it is necessary to consume this substance in supplement form.
Your body cannot produce the all-important antioxidant glutathione without cysteine, and NAC appears to be one of the most bioavailable and potent forms of this amino acid. In addition to promoting the production of glutathione, NAC also appears to exert impressive benefits throughout the body by producing neurotransmitters, removing heavy metals, and performing a wide range of other essential tasks.
If you enjoy a balanced diet with plenty of protein, you might already be getting enough cysteine to produce the glutathione your body needs. However, it's all too easy to become deficient in cysteine and its precursors, methionine and serine, so taking cysteine as a daily supplement is a good idea regardless of your current health status. NAC appears to be the most potent and useful form of cysteine that science has yet devised, but that’s hardly the full extent of this substance’s unique benefits. Whether you want to improve your immunity, boost your fertility, detoxify your body, or boost your brain, NAC may be a useful tool for fine-tuning your health and well-being.
Since NAC is considered to be one of the most bioavailable forms of cysteine, it would be natural to start experiencing the benefits of this substance after just 1-2 administrations.
Your body should fully process this highly water-soluble substance within less than 24 hours.
Since NAC is water-soluble, it will be processed into glutathione and other beneficial substances soon after absorption.
Research suggests that NAC may have its own antioxidant benefits in addition to contributing to the production of glutathione, the body’s most powerful antioxidant.
Numerous cases of NAC overdose have been reported in association with the use of this substance to treat acetaminophen overdose. Symptoms of NAC overdose include respiratory distress, vomiting, and high blood pressure.
NAC rapidly dissolves after ingestion and is used to produce other compounds.
Antioxidants may help with weight loss, and NAC does not interfere with any common dietary restrictions.
NAC is considered synthetic since it is a modified form of L-cysteine. However, NAC is not made using artificial chemicals.
NAC appears to have substantially higher bioavailability than natural forms of cysteine.
In addition to offering higher bioavailability, NAC also appears to exert benefits that are not offered by L-cysteine, so this augmented form of cysteine may actually be superior to natural alternatives.
NAC is generally taken orally in the form of a supplement.
In 2020, a lab study was published indicating that NAC may improve the cognitive deficits caused by depression by altering your neurochemistry, providing further evidence for NAC’s critical role in brain heath. Also in 2020, a new study added further emphasis to the idea that NAC may help with liver detoxification by showing that this amino acid may reduce the muscular degeneration symptoms associated with severe liver disease.