6 Best NAC Supplement Brands to Buy in 2023
Last Updated: July 13, 2023
NAC is short for N-Acetyl Cysteine (or Acetylcysteine), which is a synthetically made form of L-cysteine (or cysteine). The latter is a semi-essential amino acid that has several biological functions in the human body, the most notable of which is being a precursor to the powerful antioxidant glutathione.
Cysteine is found in many high-protein foods, such as chicken, beef, tuna, eggs, and others. Although the synthetic form N-Acetyl Cysteine (NAC) does not exist in nature, it is still widely considered a dietary supplement because it is a derivative of a naturally occurring amino acid.
Best NAC Supplements to Buy in 2023
The following are six of the best NAC supplement brands you can find and order online these days:
1. NOW Foods
NOW Foods, or just NOW, is one of the largest and most reputable manufacturers of nutritional supplements in the USA and also worldwide.
The reason many people trust this brand is simple: they make high quality, lab tested and verified products which are sold at competitively low prices.
Since they produce massive quantities, they are able to source the raw materials at a discounted bulk price, which allows them to sell at lower retail prices compared to many of the smaller manufacturers out there.
NOW’s NAC comes in two forms: 600 mg capsules ($12.99 per bottle of 100), and 1000 mg tablets ($20.78 per bottle of 120).
Important note: The capsule formula contains two additional active ingredients, which are selenium and molybdenum. These two minerals help the body utilize NAC, but they come with some cons; taking more than one capsule a day may cause adverse effects due to consuming too much of these minerals. Also, when exposed to air, these ingredients may oxidize and form dark specks inside the capsules (the company says that’s safe to consume). The tablets contain a higher dose of NAC (1000 mg each) and they don’t contain these extra minerals.
2. Thorne
Thorne is one of the most trusted professional supplement brands in the USA. They distribute their products through local health care practitioners and a few authorized online retailers. They source their ingredients from reputable global suppliers that have environmentally responsible practices.
This company doesn’t use an unnecessary additives in their products and they thoroughly test all of their raw ingredients to ensure they are free from common contaminants and harmful chemicals.
Thorne’s quality standards are among the highest in the industry and most people who’ve used their supplements attest to this.
On the negative side, this premium practitioner brand doesn’t come cheap. One bottle of Thorne’s NAC (90 capsules x 500 mg) costs $28.
3. Life Extension
Life Extension is another very reputable maker of dietary supplements that are mostly on the affordable side. They are currently one of the top suppliers of NAC and they seem to have a massive stock of this item while many other companies are struggling with supply and logistic issues.
One of the most appreciable advantages of this brand is that, contrary to what other companies have been doing, they’ve resisted the temptation to raise the price following the increased demand for this supplement. One bottle of 60 capsules currently sells at $12.
4. Natural Factors
Natural Factors tops the list of trusted supplement manufacturers in Canada. Their products are mainly sold in Canada and the USA at reasonable prices. They adhere to stringent Canadian regulations and they test the authenticity and purity of their products in a third-party lab called ISURA.
NAC by Natural Factors comes in vegetarian capsules in two strengths: 500 mg and 600 mg. A 90-capsule (500 mg) bottle costs $13.97.
5. Source Naturals
Source Naturals is a small company based in Scotts Valley, California. For many years now, they’ve been making decent nutritional supplement formulations which they offer for sale at relatively low prices.
This is one of the few companies that didn’t greedily jack up the price of this highly in-demand product during the past couple of years, for which they deserve a big thumbs up.
Their NAC comes in 600 mg tablet form and costs about $20 per bottle of 120 tablets.
6. LiftMode
LiftMode is a well-known vendor in the nootropics field, which mainly deals with cognitive enhancers and brain health supplements. But they also have a diverse selection of supplements for other uses.
Most of their products come in pure powder form without additives. They perform third-party lab tests to verify the authenticity of each batch of raw ingredients (the lab reports/COAs are published on their site).
LiftMode is currently running a sale on NAC powder where you can get a 200-gram container for $21.83 instead of the regular price of $25.68.
Where to Buy NAC Supplements Online?
Although it’s back on Amazon after being banned for a while, I generally don’t recommend buying NAC (or any other supplements) from Amazon.
Most supplements on Amazon are sold by third-party vendors who aren’t vetted. Countless fake products are traded on the platform, and sometimes these are among the top-rated items in their category.
You can get better service and 100% authentic products from one of the numerous reputable online nutrition stores that source their products directly from the manufacturers.
One of the decent places where you can find and order legit NAC brands is iHerb. Their prices are competitive and they ship worldwide.
Should You Buy NAC Powder or Capsules?
As a dietary supplement, NAC comes in powder form as well as capsule and tablet forms. Most companies offer it in capsule form, which is the most recommended and easiest-to-use option.
Some people who intend to inhale NAC look for the pure powder form, however, it is not advised and may not be safe to inhale this substance without consulting with a doctor.
Another thing to note here is that because this compound contains sulfur, it normally has a bad sulfuric smell and taste. It may smell like rotten eggs, which makes the powder unpleasant to ingest and some people may not be able to tolerate it at all. Some products have a stronger smell and taste than others.
What to Look For When Buying a NAC Supplement
There are a few important characteristics that set apart good NAC brands from bad ones.
The following are some of the key factors to take into account as you shop around for a NAC supplement. These were part of my selection methodology used to create this list.
Brand Reputation
When buying any type of supplement, you should stick with manufacturers that have an established reputation in the industry.
A trustworthy company should be transparent about who they are, where they manufacture their products, and what certifications their facility and products have.
I’ve thoroughly researched numerous brands on the market and selected the ones that are among the most reputable based on their history and customer feedback.
Testing
Most of the ingredients used to make dietary supplements are sourced from foreign suppliers in different countries.
GMP compliant manufacturers are required to conduct various analytical tests on their raw ingredients as well as finished products to make sure they are authentic, potent and safe.
I’ve selected companies that comply with GMP regulations regarding quality and safety testing so you can be confident you’re getting the real deal.
Product Form
NAC comes in different forms including pure powder, tablets and capsules.
The powder is the cleanest form as it normally contains no additives (unless it’s flavored). However, due to NAC’s unpleasant taste and the hassle of handling it, most consumers avoid the powder form.
Tablets may seem more convenient for some people, but these usually come with additional binders and fillers that you may not wish or need to consume.
Capsules are the most popular form of NAC supplements. They are easy to swallow and usually contain very few additives. Most of the products I chose for this list come in capsule form.
Price
This one is somewhat tricky because you cannot judge a product merely by its cost. People often associate a higher price with better quality, but when it comes to supplements, that’s not always the case.
The price should be justifiable relative to what you’re getting. Several factors can affect the price to a greater extent than the quality of the ingredients does.
The size of the company and its staff, the level of expertise of the staff, the location of the manufacturing facility, the type of manufacturing and lab equipment and technology, marketing spending, and a few other things are all factored into the retail price of the final product.
I tried to provide options with varying price points to suit different budgets. These include notably affordable brands as well as a few premium/professional ones that are on the higher end of the price scale.
The FDA Cracks Down
NAC supplements have been available on the market for decades and people have used them for different health purposes. But as it became highly popular lately, the FDA stepped in and said, nope, this can’t be sold as a dietary supplement anymore, because it’s a drug! They’ve issued several warning letters to different manufacturers demanding them to stop selling NAC as a dietary supplement.
Technically speaking, yes, NAC was approved as a mucolytic (mucus thinner) medication back in 1963, and again in 1985 as a treatment for acetaminophen poisoning. However, it is rarely used for these two cases and the vast majority of consumers use NAC as a supplement to support antioxidant activity and for other potential health benefits.
It doesn’t really make much sense for the FDA to ban the sale of NAC supplements. It is basically a food-like product that is very safe and normally has no significant side effects. Many other synthetically made amino acids are freely sold as dietary supplements and NAC should be no exception.
Some companies and organizations are fighting back against the FDA’s position on this nutritional compound. The Natural Products Association is suing the FDA and asking courts to block its unlawful action against NAC-containing products, according to a statement released by NPA.
Benefits of NAC Supplements
The following are four of the most noteworthy health benefits of NAC. There are other potential benefits, but these are the most widely studied and scientifically backed.
Antioxidant Production: NAC provides your body with the amino acid cysteine, which together with the amino acids glycine and glutamine is needed for the body to produce the antioxidant glutathione (GSH). This is the most powerful and crucial intracellular antioxidant in the body that helps in neutralizing free radicals, reducing cellular damage, and enhancing immune function. It can also help reduce inflammation of the lungs resulting from certain lung disorders. Since cysteine is the rate limiting factor for glutathione synthesis, increasing its levels can profoundly boost GSH production.
Liver and Kidney Detox: NAC works as a chelating agent and may help the body get rid of metal toxins. Studies have noted its potential in protecting the liver and kidney against toxin-induced damage.
Improved Respiratory Function: Due to its potent antioxidant, anti-inflammatory and mucus-thinning effects, NAC has been medically used to help dissolve mucus and improve breathing in people suffering from certain inflammatory lung diseases, such as pneumonia and bronchitis. Several studies have shown promising results, and there has been an increasing medical interest in the potential uses of this compound for lung-related disorders.
Improved Cognitive Function: Oxidative stress plays a key role in the development of neurodegenerative disorders and contributes to cognitive decline in aging people. By boosting glutathione levels in the brain, NAC may help improve brain health and combat cognitive decline and other mental health problems that result from or are worsened by oxidative stress and damage.
It is important to keep in mind that these benefits and others may only apply to certain cases. Results vary for each individual and not everyone may experience a positive change when taking NAC. It is advisable to consult with a doctor to discuss the potential benefits and efficacy of NAC for your individual case.
What Are The Side Effects of NAC?
NAC is generally safe and well tolerated and has no major side effects in most users. However, each body may respond differently to NAC and some adverse effects have been reported in some cases.
The most common side effects include: stomach upset, diarrhea, fatigue and depression. The last one is a bit ironic because NAC has been used to ease depression, but just like with other substances that can affect chemical balance in the brain, some people may experience the opposite effect.
Some people may experience insomnia when taking NAC in the evening, in which case it should be taken in the morning.
Unless otherwise advised by your doctor, keeping your total daily dosage at 600mg or below, and splitting it into 2–3 smaller servings taken at different times may help in reducing possible side effects.
Do You Need to Take NAC?
Most of NAC’s health benefits are linked to its role in increasing glutathione synthesis in the body. NAC is a supplement form of cysteine (L-cysteine), which is a semi-essential amino acid that the body can produce using other amino acids (serine and methionine) and also obtain from food.
Healthy people who regularly consume foods that contain cysteine should not need to supplement with NAC, and in case they do, it probably won’t do them much, if any, good.
Note: Although many people use the words cysteine and cystine interchangeably, they are not quite the same thing. Cystine is the oxidized form that consists of two cysteine molecules. Cystine is the form that is normally found in food. The body converts cystine into cysteine using the enzyme cystine reductase.
The following are some of the foods richest in this amino acid (the corresponding amount of cystine per 100 grams is displayed between parentheses):
- Sunflower seeds (383 mg per 100 grams) [source]
- Beef (345 mg per 100 grams) [source]
- Chicken breast (336 mg per 100 grams) [source]
- Tuna (321 mg per 100 grams) [source]
- Eggs (292 mg per 100 grams) [source]
- Swiss Cheese (290 mg per 100 grams) [source]
- Lentils (118 mg per 100 grams) [source]
The Bottom Line
NAC is a synthetically made form of the amino acid cysteine. Although it is an approved medication for certain health conditions, it is widely used as a dietary supplement and has a good safety profile. Its primary use is to help the body replenish glutathione levels and promote antioxidant activity within the brain and throughout the body.
Despite the numerous promising studies and potential therapeutic effects, not everyone may benefit from supplementing with NAC. Healthy people who have no compelling reason to take NAC are better off sticking with nutritious foods (see the list above) to provide their body with adequate amounts of the amino acid cysteine.
References
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