Tyler Sellers
Published by Tyler Sellers
Fact checked by Donald Christman, BHSc FACT CHECKED
Last updated: February 19, 2021

N-Acetyl-Cysteine (NAC) was quite a new concept for me, and I often shy away from stuff I can’t pronounce. But when I saw some of my clients taking NAC for dealing with symptoms of excessive free radical levels, I knew I needed to pay more attention.

The first thing my dietitian told me was that I needed to be careful with these supplements, as only the ones with the purest form of N-Acetyl-Cysteine might help with detox efforts.

So, we bought as many of these as we could find and had them analyzed by our dietitian.

Here is our list of best NAC supplements.

Our Top NAC Supplements

1 - NOW Foods NAC (Editor's Choice)


NOW NAC is at the top of our list because it provides one of the higher doses available. The dose also seems to match up with some clinical trials of N-acetylcysteine for brain, heart, lung, and liver support.

We also like that the company uses an independent lab to test the quality and purity of the N-Acetylcysteine.

Dose: 1,000 mg

  • Positive comments from users in detoxes
  • Free from the most common allergens
  • Independently certified for a higher quality product
  • Comes in a large bottle of 120 tablets
  • The tablets are a little bit on the large side

Just be aware that you might want to break the tablets in half if you tend to struggle to swallow large pills.

2 - Source Naturals NAC

Source Naturals NAC

This is another one of the NAC supplements with a higher dose to save you from having to swallow multiple capsules.

We noted quite a few online comments from people who may have had good results for their liver function and to deal with an accumulation of free radicals.

And if this one suits you, then you can also save some money on the larger bottles available.

Dose: 1,000 mg

  • No artificial additives or fillers
  • May work well for liver and respiratory health
  • Available in large bulk bottles
  • It’s not the cheapest option

While it is stronger than most other supplements, it’s also one of the most expensive ones available.

3 - Designs for Health NAC

Designs for Health NAC

Here’s an NAC supplement with a high average user rating from people who found that it may help to improve brain function. If you're a student or work on a computer all day, then this might be a good reason to give it a try.

What we also liked is that this is made by one of the few companies that also focus on eco-friendly packaging to reduce single-use waste.

Dose: 900 mg

  • Positive comments about alertness and mental clarity
  • Made in the USA and tested for purity
  • Comes in sustainable packaging with reduced waste
  • Some bulk order discounts would be great.

We just wish there were some larger bottles or bulk discounts available, especially if you plan to take it for the long term.

4 - Bulk Supplements NAC

Bulk Supplements NAC

Bulk Supplements is a well-known brand, and this product is suitable for folks who like to have more flexibility in adjusting the dosage.

It delivers 600 mg per capsule, and some folks have reported good results by taking it up to three times per day.

The powder also means that you might find it easier to take if you mix it in with a smoothie in the morning.

Dose: 600 mg

  • Comes in powder form to mix with smoothies
  • Available in large pouches making it more cost-effective
  • Mixes easily without the need for a shaker
  • It’s not convenient for taking throughout the day

You’ll just need to figure out how to easily bring it with you if you plan to take it more than once a day.

5 - Nutricost NAC

Nutricost NAC

This is one of the products that had quite a few comments about the effect kicking in a lot sooner than some folks had expected.

It’s also one of the few that has a vegan certification, and the large bottles available might save you some money.

Dose: 600 mg

  • Positive comments about the antioxidant properties kicking in quickly
  • Vegan-friendly option thanks to veggie capsules
  • Large bottle of capsules may last longer than others
  • The dosage per capsule is quite low compared to other products

The 600 mg of NAC should give a reasonable boost in glutathione levels, but some people might need to consider taking more capsules to deal with high free radical levels.

6 - Swanson NAC

Swanson NAC

The lower dose in this one also means that the capsules might be that bit smaller for you to swallow. It’s something that I personally prefer as I somehow struggle with large pills.

It should deliver a good boost in glutathione to help with free radical removal through your liver and kidneys.

And the money-back guarantee may help convince you to take a risk-free trial.

Dose: 600 mg

  • Capsules are easy to swallow without getting stuck
  • May provide a good amount of glutathione for immune system support
  • Money-back guarantee makes it a risk-free trial
  • We couldn’t find any bulk discounts

We tried to find the product in larger bottles or bulk orders, but there don’t seem to be discounts available.

7 - Life Extension NAC

Life Extension NAC

The Life Extension NAC product is one of the supplements that we noted quite a lot of comments about the positive immune benefit.

We also noted that reviewers seemed to be getting good results from the content of just one serving of the amino acid. And we couldn’t find any references to negative side effects, even at higher doses.

Dose: 600 mg

  • Many positive reviews about health benefits for your immune system
  • Most people report good results from just one capsule per day
  • No reports of side effects from users
  • Only available in small bottles

Just keep in mind that it’s not available in large bottles to get some better discounts for long term use.

8 - Jarrow Formulas NAC

Jarrow Formulas NAC

Jarrow Formulas was a new brand for me, but it seems like the company makes a good selection of supplements.

It’s certified non-GMO, as well as gluten and soy-free to help you avoid some of the more common allergic reactions to supplements.

And we also liked that there are absolutely no fillers that so many other companies tend to use.

Dose: 500 mg

  • Good results reported by people trying to repair oxidative damage
  • Avoids use of any allergens
  • Delivers pure NAC with no fillers or additives
  • One of the lowest doses we found

Just keep in mind that Jarrow Formulas dosage is probably the lowest on this list, which you need to consider when comparing the prices.

9 - Thorne Research NAC

Thorne Research NAC

We liked this one because the company puts a lot of effort into sourcing the purest ingredients. It then takes it one step further by having it third-party tested so that your body gets the best ingredients.

Even with the lower dosage, there are plenty of reviews that highlight a good glutathione boost for improved heart, lung, and immune health.

Dose: 500 m

  • Third-party tested for purity and quality
  • Claims to only use pure NAC avoiding any fillers
  • Should support a boost in glutathione to help repair oxidative stress
  • There don’t seem to be larger bottles available

As it only has 500 mg per capsule, some folks might plan to take several a day, but unfortunately, this product isn’t available in larger bottles to support that.

10 - Best Naturals NAC

Best Naturals NAC

The final one of our best NAC supplements is another 600 mg option, which some folks prefer as it may allow more precise dosage planning.

We noticed quite a few reviews that highlighted benefits for lung function as well as blood pressure.

Dose: 600 mg

  • Seems to live up to its claim of being a powerful antioxidant
  • Good results reported by folks who take it for improved lung function
  • Independently tested for purity
  • Some reports of capsules sticking together in the bottle

The reason it’s further down on the list is that we did see a few comments that the capsules sometimes get stuck together in the bottle.

Buyer’s Guide

Supplements Choices

1. Dosage

Unless your physician has given you instructions for a specific dose, 600 mg is a good starting point per day [1]. But you might want to gradually increase that to 1,000 mg to give your body the full benefits.

“N-acetyl cysteine is most commonly used by mouth for cough and other lung conditions. It is also used for flu, dry eye, and many other conditions, but there is no good scientific evidence to support many of these uses.” - WebMD.com.

Now, when you are comparing the above products based on price, make sure that you make your calculations based on the dosage as well.

Some of the supplements might not look all that affordable, but with a higher amount per capsule, you might be getting a much better deal.

2. Quality Ingredients

When it comes to N-Acetyl-Cysteine, it’s all about purity.

You don't want to see long lists of fillers and other unnecessary ingredients that might just distract from your health goals.

Ideally, you want to pick one of the supplements that use independent testing labs to certify the purity, as this may give you more peace of mind.


Is It Ok to Take Nac Every Day?

Yes, it’s OK to take NAC every day. But you may want to consider taking some occasional off cycles. Many people have come to rely on it for their long term detox efforts.

When Should You Take an Nac Supplement?

You should take an NAC supplement first thing in the morning before breakfast. This may allow it to absorb faster and give you a boost for the day.

Which NAC Supplement Gave Us The Best Results?

Based on user reviews and our own test results, we think that the NOW Foods product is one of the best NAC supplements.

It has a high enough dose to make a difference and seems to have a great quality source of amino acids.

Order yours today and report back to us on how it improved your health.



Our #1 Recommendation

  • Positive comments from users in detoxes
  • Free from the most common allergens
  • Independently certified for a higher quality product
  • Comes in a large bottle of 120 tablets
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