(NOTE: Updated some of the products and vendors mentioned on July 25, 2010.)
N-Acetylcysteine is an inexpensive and highly absorbable form of the amino acid cysteine which has numerous health benefits. Previously, I’ve mentioned NAC for use as a preventive measure against the common cold and flu infections (see Preventive Measures for Swine Flu ), to help prevent liver damage from Tylenol (see Health Risks from Tylenol, Acetaminophen, and Paracetamol ), and to detoxify your body of the mercury in dental fillings, predatory fish, and high fructose corn syrup (see High Fructose Corn Syrup is Dangerous for Many Reasons ).
NAC Also Useful in Mental Health
It turns out that NAC also has uses in mental health and psychiatry, too. There is now clinical trial evidence that it can be used to treat trichotillomania , an impulse control disorder involving pulling the hair out of one’s head, eyelashes, eyebrows, or elsewhere on the body. This disorder affects somewhere between 1% and 5% of the world’s population and is strongly female predominant. Estimates are that 70% to 93% of trichotillomania patients are female. There is a belief that the disorder may have genetic origin, but so far the related genes found don’t explain all cases of the disorder.
Gene Found that Explains About 5% of Trichotillomania Cases
Trichotillomania Is Highly Embarrassing and Difficult to Control
People who suffer from trichotillomania say they often keep it a secret. When others discover their secret, the first reaction is often “why don’t you just stop pulling your hair?” But the urge to pull hair is so strong that they can’t stop and often may not be fully aware of what they are doing.
Trichotillomania: A Hair Pulling Gene
University of Minnesota Finds NAC Reduces Hair Pulling Significantly
In September 2008, a study conducted by the University of Minnesota involving attempts to treat trichotillomania  with NAC was completed. The study was structured as a double-blind study with some patients taking NAC and others taking placebo tablets. The results published in July 2009  show that during the course of 12 weeks of treatment with between 1200mg and 2400mg of NAC per day, 56% percent of patients experience a significant reduction in hair pulling versus only 16% taking a placebo. Improvements were generally evident starting about 9 weeks after the start of NAC treatment.
The theory on how NAC works to reduce trichotillomania behaviors is that it balances levels of excitatory neurotransmitters such as glutamic acid that are involved in anxiety and compulsive behaviors:
(from Amino Acid Reduces Compulsive Hair Pulling )
There is no FDA approved treatment for the condition, but previous clinical studies have shown that glutamatergic modulators, such as N-acetylcysteine, may be effective in treatment of repetitive or compulsive disorders.
N-acetylcysteine is a hepatoprotective antioxidant that is converted to cystine, a substrate for the glutamate-cystine antiporter.
The researchers wrote that it may reduce compulsive behavior by restoring the extracellular glutamate concentration in the nucleus accumbens, the portion of the brain thought to play a key role in reward, laughter, pleasure, addiction, and fear.
Most medication treatments attempted for trichtotillomania were not very effective. Some actually make the condition worse. Attempts at using SSRI antidepressants have been found to worsen the symptoms for some people.
Doctors have used tricyclic antidepressant clomipramine  for treating OCD and have found that it also reduces trichotillomania symptoms as discussed in the study A double-blind comparison of clomipramine and desipramine in the treatment of trichotillomania (hair pulling) . However, clomipramine has a variety of dangerous side-effects and drug interactions.
NAC: A Safer Alternative
NAC is a far safer substance than clomipramine. It is a variant of L-cysteine, an amino acid commonly found in the body.
Much larger dosages have been studied. One study with AIDS patients involved dosages up to 8000 mg per day without significantly harmful effects. There has been little indication of side-effects or drug interactions from NAC using reasonable dosages.
Very extreme dosages studied in a mouse model showed that such extreme NAC dosages could cause blood pressure increases and lung problems similar to that experienced from long-term hypoxia (low oxygen levels). However, other research in humans with more reasonable dosages suggest that this effect is not likely to be found in humans. Monitoring blood pressure is a very easy thing to do, and something that is a good idea for most people to do in any case given the widespread incidence of hypertension in adult populations consuming Western diets such as those in the US, UK, Canada, and Australia.
Probably the biggest caution for NAC is that some studies suggest that some people using NAC experience kidney stones that may result from inadequate intake of vitamin C when NAC is being used. It is suggested that three times the intake of vitamin C be taken along with each dose of NAC. So if you take a 600 mg capsule of NAC, take a three or four 500 mg or two 1000 mg tablets of vitamin C at the same time.
NAC also boosts the body’s utilization of vitamin B6, so you should also take a vitamin B complex supplement that includes vitamin B6. This is a good idea regardless of whether you are taking NAC or not as many illnesses are exacerbated by low levels of the various types of B vitamins. Be cautious about overdoing it with vitamin B6 as high consumption, often cited as more than 200 mg per day, may lead to nervous system problems such as numbness or tingling in the fingers and toes and clumsiness from degraded muscle coordination. If you have a choice, P5P (pyridoxal 5 phosphate) is the preferred form of vitamin B6 as it is already bioactive and studies suggest it is less likely to cause the side effects of the cheaper very common pyridoxine form.
It appears that NAC helps the body to balance out levels of glutamate, an excitatory neurotransmitter formed by glutamic acid. Glutamic acid is widely found in foods such as soy sauce, seaweed products, and the flavor additive monosodium glutamate . Some people seem sensitive to glutamic acid in their diets and develop symptoms such as headaches and worsened asthma.
There is some discussion on the web about the connection between foods eaten and urges to pull hair. The article Diagnose-Me: Trichotillomania  discusses the possible connection with certain foods:
If people are interested in seeing if their hair pulling is food-related, there is a simple test that can be done. Simply eating a snack such as peanut M&Ms (containing sugar, chocolate and legumes) – as many as you can stand at one sitting, washing them down with Coca-Cola (cola, caffeine and more sugar or aspartame, which is just as bad) is all that it takes. If in 2 days there is a noticeable increase in hair pulling urges, then you could consider abstaining from “bad” foods.
Unfortunately, it appears to take from 30-40 days to purge the gut and skin of their bad effects fully, and it also seems to take several attempts and about a year of trying for most pullers to achieve the desired results. People report that avoiding sugar and caffeine – which act more quickly – is the most rewarding way to start.
The list of foods that aggravate this condition includes concentrated natural sugars, tomato seeds, soy products, yams, MSG, and ibuprofen. However, there are a few “good” foods, which partially counteract the “bad” ones, including garlic, most acidic fruits, dry red wine, unsweetened yogurt, and a chemical family called gluconates.
Connection Between Trichotillomania and OCD
Trichotillomania may be related to obsessive-compulsive disorder in some way, perhaps at a neurochemical level. It is a topic of hot debate, with some claiming that there is no connection at all. Yet trichotillomania patients have higher rates of anxiety, depression, and obsessive-compulsive disorder diagnoses. A study titled Severe obsessive-compulsive disorder with and without comorbid hair pulling: comparisons and clinical implication  found that female and severe OCD patients often also suffer from compulsive hair pulling and trichotillomania at higher rates.
Trichotilllomania is sometimes grouped together with disorders such as pyromania  which involves a compulsion to start fires which produces a sense of gratification or relief. It’s also related to kleptomania  which involves a compulsion to steal and hoard things that are typically of little value.
Trial Treatment for OCD Using NAC
Yale University is running a study on the use of NAC for treatment of Obsessive-Compulsive Disorder (OCD). This study uses a dosage of 3000 mg of NAC per day. They are still recruiting study participants. Visit the web page N-Acetylcysteine Augmentation in Treatment-Refractory Obsessive-Compulsive Disorder  if you’re interested in learning more about this study, or email [email protected]  for more information.
NAC Supplementation is Inexpensive
The wide range of benefits of NAC include improving immune system health, detoxifying the body of mercury, protecting the liver from acetaminophen by-products, and building stores of the antioxidant glutathione. The nutrient appears to be important for many reasons applicable to nearly everybody.
NAC contains sulfur, so it smells a bit like rotten eggs. I take NAC myself for its immune-boosting and anti-oxidant boosting properties and find that the NAC capsules are easily swallowed and do not generally cause digestive discomfort or other problems. Daily dosages of up to 1200 mg are widely regarded as safe long-term use for my type of usage.
If you shop carefully, you can get a year’s worth of 600 mg of NAC per day for less than $30. That’s considered to be a good starting point for overall general health. Be sure to take vitamin C and vitamin B6 with it, also. As mentioned, take about three times as much vitamin C as NAC.
The mental health benefits being observed from NAC treatment are icing on the cake for most people, but for those suffering from anxiety, obsession, and compulsion behaviors there’s a decent chance based upon recent studies that NAC may help improve their lives. It appears mental health treatment using NAC will require larger doses, perhaps 1200 mg to 3000 mg per day, and that it may take two to three months for improvements to be noticed.
Where to Buy NAC
NAC isn’t just for people with OCD and trichotillomania. It is a good supplement for most people with any kind of chronic fatigue, anxiety, or pain condition because so many of these problems in part involve low levels of glutathione. It is also great for helping improve health during or after infections as the body’s immune reaction tends to spew oxidative compounds at bacteria and viruses to kill them off. This tends to deplete glutathione, so adding NAC can help the body regenerate the large amounts lost due to fighting an infection.
Some of the least expensive sources for N-acetylcysteine supplements are online dietary supplement vendors, particularly if you can find the product in a bulk powder form.
Swanson Health Products sell their N-Acetyl Cysteine 600 mg 100 Caps  product for $6.99 per bottle at the time of this update. That works out to a year’s supply of 1200 mg per day for about $51. That’s enough for 2 capsules per day, the base dosage used in the recent University of Minnesota trichotillomania study, for a bit over a year.
Some NAC formulations including other essential trace nutrients that complement NAC at comparable prices. NOW Foods 600 mg NAC with Selenium and Molybdenum  includes 25mcg of selenium  and 50mcg of molybdenum  per capsule. It is priced around $20 for a bottle of 250 capsules. While this combination can be really helpful as these nutrients are involved in the use of NAC to make glutathione perioxidase, there is some danger of toxicity if you get too much selenium in particular. For molybdenum, the risk is quite low compared to selenium. If you take other supplements that have selenium, add up the total amount consumed per day. Be cautious about not getting too much selenium as it can cause adverse health effects including garlic scent on the breath, gastrointestinal disorders, hair loss (obviously not good for somebody with trichotillomania!), sloughing of nails, fatigue, and irritability. The upper limit for selenium intake is variously expressed from 400 mcg to 800 mcg per day or 15 mcg per kilogram of body weight. A year’s supply of this product at 1200 mg per day costs about $60, meaning there is little additional cost for the added benefits of the selenium and molybdenum versus Swanson Health Products.
NAC available from other reputable vendors includes Life Extension’s 600 mg bottle of 60 capsules . The price typically ranges from about $10 to $12 per bottle, depending upon quantity.
I have often used NAC purchased in bulk powder form because it can be a lot less expensive than capsules. So long as you are not overly sensitive to the mild sulfur taste it can be a good way to get the benefits of NAC at a lower cost. When I first wrote this article, I found it was often priced at less than half the price per milligram versus many inexpensive sources of NAC capsules. Unfortunately, while updating this article to reflect currently available products, I found that it appears much more difficult now to find NAC powder in the 1000 gram size which used to be readily available and quite inexpensive. You might try locating a supply in that size at NutraBio  or PureBulk  if you have tried it as capsules and found you want to continue taking it long-term.
Please see my article Review: 1FAST400 N-Acetylcysteine (NAC) Bulk Powder  for more information on how NAC powder mixes, tastes, smells, and other nutrients you should consider taking with it. Other bulk NAC powders are likely to be similar to it, so the information in that review may also be helpful if you find another source even though that particular product is no longer available.
When bulk powders were not convenient, I have usually used the NOW Foods 600 mg NAC with Selenium and Molybdenum  product. Both it and the similarly priced Swanson Health Products N-Acetyl Cysteine 600 mg 100 Caps  product are well-priced options.
These statements have not been evaluated by the Food and Drug Administration. The products mentioned in this post are not intended to diagnose, treat, cure or prevent any disease.