Research & Education

N-Acetyl Cysteine’s Role in Supporting Healthy Aging

Research suggests two critical factors that may support healthy aging: mitigating the effects of oxidative stress and promoting healthy mitochondrial function. N-acetyl cysteine (NAC) may play a supportive role in both by promoting normal glutathione (GSH) production and maintaining a healthy antioxidative and anti-inflammatory status.  

NAC, an amino acid, can be found in small amounts in certain fruits and vegetables. It promotes intracellular GSH – the most abundant endogenous antioxidant. GSH is critical for liver detoxification of heavy metals and other xenobiotics and for systemic antioxidant support to help protect against oxidative stress and free radical accumulation. Unfortunately, GSH levels decline with age, which may be associated with increased oxidative stress and mitochondrial dysfunction. NAC also supports the production of multiple anti-inflammatory compounds.

Oxidative stress and mitochondrial dysfunction universally affect all cells and organs. They are described as "two sides of the same coin with one leading to the other.” Elevated oxidative stress is associated with cellular dysfunction and potentially worsens a deficiency of endogenous GSH. Meanwhile, mitochondrial dysfunction is associated with decreased energy production and may disrupt cellular processes that rely on energy for sustained function.

In a small study of older adults (n = 8) who supplemented with NAC (in combination with glycine) for 24 weeks experienced reduced GSH deficiencies, oxidative stress, mitochondrial dysfunction, and genomic damage. Similar statistically significant benefits were observed in a rodent study. Notably, potentially owing to these benefits, the mice receiving the NAC supplement lived 24% longer than the control mice.

In a small randomized controlled trial (n = 24), older adults (aged 61 to 80) and young adults (aged 21 to 40) were given either a NAC-containing supplement or a placebo. The older adults exhibited various characteristics associated with aging at the beginning of the trial, such as GSH deficiency, impaired mitochondrial function, elevated oxidative stress, inflammation, endothelial dysfunction, glucose dysregulation, decreased physical function, increased waist circumference, and higher systolic blood pressure compared to the younger adults. After 16 weeks of supplementation, the older adults showed improvements in all these parameters. However, a prior open-label clinical trial conducted by the same researchers indicated that these benefits might decline after discontinuing the supplement for 12 weeks, suggesting the potential need for consistent supplementation in certain individuals.

While more research is needed, NAC shows promise in potentially supporting healthy aging. Its role in supporting GSH production, mitochondrial health, and healthy antioxidative and anti-inflammatory status makes it a potential ally in helping promote a healthy aging process.

By Danielle Moyer, MS, CNS, LDN