Quick answer: N-acetylcysteine (NAC) supplies cysteine, the building block that limits how much glutathione your body makes, and it is inexpensive and well studied. Liposomal glutathione delivers glutathione itself and has small studies showing it raises body stores within weeks, but it costs much more. For most people curious about supporting glutathione, NAC is the value option; liposomal glutathione may suit those who don’t tolerate NAC. Talk to a health professional first, especially if you have asthma or take medication.
How glutathione is made
Glutathione is built inside cells from three amino acids: glutamate, cysteine and glycine. Cysteine is usually in shortest supply, so it is the main factor that limits production. NAC is a stable form of cysteine that the body converts and uses to make glutathione. For background, see our liposomal glutathione guide.
Side-by-side comparison
| NAC | Liposomal glutathione | |
|---|---|---|
| How it works | Provides cysteine so cells make their own glutathione | Delivers glutathione in phospholipid spheres |
| Typical doses studied | 600 to 1,800 mg a day | 500 to 1,000 mg a day |
| Research | Decades of medical use and many clinical trials | Small pilot studies |
| Approximate cost in Canada | Low (often under $0.50 a day) | High (often $2 to $4 a day) |
| Taste and format | Capsules; powder has a sulphur smell | Liquids, sachets or capsules; sulphur taste in liquids |
| Common side effects | Nausea, stomach upset, diarrhea | Bloating, loose stools (uncommon) |
The evidence for NAC
NAC is used in hospitals to treat acetaminophen (paracetamol) overdose, where it restores liver glutathione, and it has been used as a mucus-thinning agent for lung conditions. Clinical trials have also looked at NAC in many other areas with mixed results. Its ability to support glutathione production is well established; benefits for healthy people taking it as a daily supplement are less clear.
The evidence for liposomal glutathione
A 2018 pilot study (Sinha and colleagues, European Journal of Clinical Nutrition) found that liposomal glutathione raised glutathione levels in blood cells within one to two weeks and improved some immune markers over a month. Regular (non-liposomal) oral glutathione showed mixed results in other trials. See Liposomal Absorption Explained for why delivery matters.
Who might choose which?
- NAC: people looking for an affordable, well-studied way to support the body’s own glutathione production, under advice from a health professional.
- Liposomal glutathione: people who cannot tolerate NAC, or whose practitioner recommends direct glutathione.
- Neither: healthy people with a balanced diet and adequate protein may not need either. Sulphur-rich foods (garlic, onions, broccoli, Brussels sprouts) and protein support normal glutathione production.
Safety
- Asthma: NAC and inhaled glutathione have been linked to bronchospasm in some people with asthma. Speak to your doctor first.
- Medications: NAC may interact with nitroglycerin and some other drugs. Review all supplements with a pharmacist.
- Cancer treatment: ask your oncologist before taking antioxidants during chemotherapy or radiation.
- Pregnancy and breastfeeding: use only on medical advice.
- Choose products with an NPN (how to check).
Frequently asked questions
Can I take NAC and glutathione together?
Some products combine them. There is little research on the combination; ask a health professional whether it makes sense for you.
Is NAC available in Canada?
Yes, NAC is sold in Canada as a licensed natural health product. Check the NPN and approved uses on the label.
Which works faster?
In the pilot study, liposomal glutathione raised levels within one to two weeks. NAC also raises glutathione, but timing depends on dose and individual factors.
Sources
- Sinha R, et al. European Journal of Clinical Nutrition, 2018.
- Richie JP Jr, et al. European Journal of Nutrition, 2015.
- Review literature on N-acetylcysteine pharmacology and clinical use.
- Health Canada. Licensed Natural Health Products Database.
This article is for general information only and is not medical advice. See our medical disclaimer.
