N-Acetyl-Cysteine (NAC)

N-Acetyl-Cysteine, or NAC, is a stable form of the amino acid cysteine. It is best known for helping the body produce glutathione, one of its major endogenous antioxidants, and is commonly used to support antioxidant defence, liver function and respiratory health.

Because cysteine can be a limiting building block for glutathione production, NAC provides a practical way to support this important protective system.

Glutathione and Antioxidant Defence

Glutathione helps protect cells from oxidative stress and is involved in the body’s normal detoxification processes.

NAC supplies cysteine that can be used to make glutathione, which is why it is often included in formulas for cellular protection, immune support and healthy ageing.

This antioxidant role is particularly relevant during periods of increased physical, environmental or metabolic stress.

Liver Support

The liver relies heavily on glutathione as part of its normal detoxification and antioxidant systems.

By supporting glutathione production, NAC can contribute to normal liver function and the body’s ability to process reactive compounds.

This makes it a common ingredient in formulas aimed at liver health, recovery and general resilience.

Respiratory Support

NAC also has mucolytic properties, meaning it can help reduce the thickness of mucus.

This has made it useful in respiratory-support formulas, particularly where maintaining clear airways and normal mucus consistency is important.

Its antioxidant activity provides an additional layer of support for tissues exposed to environmental irritants and oxidative stress.

NAC for Pets

NAC can also be used in supplements for dogs and cats to support antioxidant defence, liver function, respiratory health and cellular resilience.

In pet formulas it is often combined with other antioxidants, amino acids and immune-support nutrients to provide broader support for recovery and healthy ageing.

NAC in O2B Products

At O2B Healthy, NAC is available in O2B NAC (N-acetyl-L-cysteine), providing a concentrated source for antioxidant, glutathione, respiratory and liver support. It is also included in O2B MitoCell+, where it complements nicotinamide riboside, quercetin and resveratrol as part of a broader formula for mitochondrial function, cellular energy, antioxidant defence and healthy ageing.