Health Guide
L-Acetyl n-Cysteine
L-Acetyl Cysteine (NAC) is a modified form of the amino acid cysteine. Think of it as the body's master repair tool. Its primary job is to boost levels of glutathione, the most powerful antioxidant your body produces. While you can get small amounts of cysteine from high-protein foods, NAC is primarily used as a supplement because it is highly bioavailable and easily crosses the blood-brain barrier. It acts as a precursor to glutathione, helping to refill your body's antioxidant tank to fight off oxidative stress and inflammation.
Evidence BasedDietary Supplement
VERIFIED SOURCE
Bio-Activity Analysis
Glutathione levels with NAC
SCIENTIFIC DATA VISUALIZATION
Y-Axis
Glutathione Levels
Supplementation →
Health Benefits & Sources
Why You Need It
- Lung & Respiratory Health: NAC acts as a mucolytic (mucus thinner), making it easier to breathe and clearing airways.
- Mental Clarity & Mood: By restoring glutathione in the brain, it may help regulate glutamate levels, supporting focus and emotional balance.
- Detoxification: It is essential for liver health, helping to neutralize harmful toxins like heavy metals and pollutants.
- Fertility Boost: It has been shown to improve sperm quality and motility in men and support ovulation in women with PCOS.
Deep Dive
NAC is a 'conditionally essential' nutrient. Under stress or illness, your body's demand for glutathione skyrockets. NAC provides the raw materials to meet this demand. It works by donating sulfur atoms, which are crucial for neutralizing free radicals that damage cells. For the brain, it helps balance the 'gas' and 'brakes' of neurotransmitter activity, which explains its growing popularity for mental well-being.
Natural Food Sources
NAC itself is not found in significant amounts in food; it is a synthetic supplement. However, cysteine (the amino acid it converts to) is found in protein-rich foods. Interestingly, onions and garlic are rich in sulfur compounds that support the same glutathione pathways.
| Food | Amount of Cysteine | % Daily Value (Approx) |
|---|---|---|
| Chicken Breast | 400mg | 45% |
| Yogurt (Greek) | 300mg | 33% |
| Eggs (1 large) | 250mg | 28% |
| Sunflower Seeds | 200mg | 22% |
| Lentils | 150mg | 17% |
Supplementation
- Typical Dosage: 600mg to 1,800mg daily, divided into 2 or 3 doses.
- Best Practice: Take on an empty stomach (30 mins before food) for maximum absorption, though it can be taken with food if it upsets your stomach.
- Who Should Take It: Ideal for those with respiratory issues, high oxidative stress, or looking to support liver detoxification.
Top Food Sources
Chicken Breast
400mg per 3oz serving
Greek Yogurt
300mg per cup
Eggs
250mg per large egg
Sunflower Seeds
200mg per 1/4 cup
Lentils
150mg per cup (cooked)
Frequently Asked Questions
It is best absorbed on an empty stomach, but if you experience nausea, take it with a small snack.
For respiratory issues, effects can be felt within days. For mood or fertility benefits, it may take 3 to 6 weeks of consistent use.
Yes, it is generally considered safe for daily, long-term use, but periodic breaks are recommended to assess your body's natural glutathione production.
It may help the liver process alcohol metabolites more efficiently, but it is not a cure-all and should not be used to encourage heavy drinking.
Safety & Side Effects
Safety & Interactions
Who Should Avoid:
- Individuals with asthma should not use NAC without a doctor's supervision, as inhaled NAC can cause airway spasms (though oral use is generally safe).
- Those with a history of kidney stones should be cautious, as cysteine can contribute to stone formation.
Interactions:
- Nitroglycerin: NAC can increase the effectiveness of nitroglycerin, leading to severe headaches and low blood pressure.
- Activated Charcoal: Take NAC at least 2 hours apart from activated charcoal, as charcoal can bind to it and prevent absorption.
Side Effects: Generally safe, but may cause nausea, stomach upset, or diarrhea at high doses.
Scientific References
- [1]Baker, D. A., et al. (2021). 'N-acetylcysteine for the treatment of psychiatric disorders: A systematic review.' *Psychiatry Research*.
- [2]Mokhtari, V., et al. (2017). 'A Review on the Therapeutic Effects of N-acetylcysteine.' *Cell Journal*.
- [3]Rushworth, G. F., & Megson, I. L. (2014). 'Existing and potential therapeutic uses for N-acetylcysteine: A review.' *Pharmacology & Therapeutics*.