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You have read that NAC has antibacterial and antioxidant effects? That NAC is used as a medicine to relieve respiratory diseases and as a food supplement can strengthen your immune system?

But you would like to know more about the scientific background, the correct intake and the decisive criteria for buying NAC? Then you've come to the right place.

Welcome to our big NAC test 2021. We are pleased that you are here. In this guide, we will provide you with all the important information about NAC.

You will not only learn what healing effects NAC is said to have, but also learn a thing or two about this synthetic chemical compound.




The most important facts

  • Acetylcysteine (NAC) is a synthetically produced chemical compound which is a more stable derivative of the naturally occurring L-cysteine. NAC is usually administered in the form of medicines or dietary supplements.
  • NAC has antibacterial, antioxidant and expectorant effects. Therefore, it can be used, among other things, to alleviate respiratory diseases, to strengthen the immune system or as a dietary supplement in sports.
  • As a rule, you can distinguish between three different dosage forms. These include NAC capsules, NAC powder and NAC tablets.

The Best NAC: Our Picks

Buying and evaluation criteria for NAC

When buying NAC, you can pay attention to various aspects that will make it easier for you to compare different products and designs.

By making the right choice for you, you ensure that you do not give your body anything it does not need. Therefore, always pay attention to a high quality standard and, if necessary, ask to see the manufacturer's certificates.

Intended use

Acetylcysteine has different effects and can therefore be used in different ways. We therefore recommend that you consider your personal intended use when thinking about buying NAC.

NAC has antibacterial and antioxidant effects.

For example, NAC has antibacterial, antioxidant and expectorant effects and can be used to relieve various medical conditions. For example, you can use NAC to treat respiratory diseases such as cough.

You can also take it to generally strengthen your immune system and connective tissue, as well as a dietary supplement for sports. However, we recommend that you always discuss any plans with a doctor or alternative practitioner so that the intake is as safe as possible.

Dosage

You should always pay attention to the dosage of NAC when taking it so that you can minimise the risk of an unhealthy overdose. The advantage of taking capsules is that you do not have to regulate the amount of NAC yourself.

If you purchase acetylcysteine in powder form, the delivery may include a practical spoon that you can use to measure out the exact amount. However, we generally recommend that you always follow the manufacturer's dosage instructions or talk to your doctor.

Stock up

NAC is sold in different quantities in its various product versions. Therefore, we recommend that you take your personal needs into account when making your purchase decision.

By making the right choice, you can make a very cost-effective decision.

If you just want to try the product to see how it suits your body, we recommend that you buy a small pack. If you take the product regularly, then you can also consider buying a larger stock pack.

You should also consider the form of NAC when deciding how much to buy. For example, NAC capsules have a longer shelf life than NAC in powder form.

Ingredients

Acetylcysteine products may contain various additional ingredients depending on the type of product. We recommend that you check these before making your purchase decision.

NAC in powder form is usually produced without additional ingredients and consists of 100 percent pure acetylcysteine. If you prefer to buy NAC in tablet or capsule form, you can expect to find other ingredients such as citric acid and cellulose. The capsules themselves, however, are often produced on a vegetable basis.

Guide: Frequently asked questions about NAC answered in detail

In order to inform you comprehensively about the effectiveness of NAC and to give you an understanding of the current state of science, we have summarised all the important information in the following sections.

What is NAC and how does it work?

Acetylcysteine (NAC) is a derivative of the naturally occurring L-cysteine, a non-essential sulphur-containing amino acid (1). However, unlike L-cysteine, acetylcysteine is a more stable synthetically produced compound and is therefore not found in food.

Due to its stability, NAC is usually administered in the form of medicines or food supplements.

NAC preparations are a popular dietary supplement in sports. (Image source: Unsplash / Scott Webb)

Among other things, NAC has significant antioxidant effects and functions as a glutathione intermediate, which is why it can be used in so many ways (4, 10). To give you a good impression, we have summarised the most important effects below:

  • Medicines for respiratory diseases
  • Strengthening the immune system
  • Food supplements for sport

You can find out more about the details of the respective effects in the following section.

Effect on respiratory diseases

NAC can help cleanse your body of harmful free radicals and neutralise them. This is especially important for preventing oxidative stress, a condition that can weaken your immune system.

Oxidative stress can promote the development of respiratory diseases, such as lung disease (2, 8).

Acetylcysteine is often used in medicine as an effective cough suppressant due to its antioxidant and expectorant properties.

Acetylcysteine has mucolytic and expectorant functions that have been extensively tested in patients with chronic bronchitis.

The results showed that taking acetylcysteine can relieve the symptoms of chronic bronchitis without producing an increased risk of side effects (3, 8, 9).

Effect in strengthening the immune system

Cysteine is a semi-essential amino acid that supports the formation of glutathione in the human body. Glutathione is very important for the health of your body as it has a highly antioxidant effect and can thus effectively protect you from pathogens.

Glutathione is an essential antioxidant in your body.

Glutathione plays a major role in strengthening your immune system. If there is not enough of it, your body cannot fight pathogens effectively. To prevent your quality of life from being permanently affected by illness, you can take NAC as a food supplement (4, 10).

As already mentioned, NAC is a more stable derivative of L-cysteine. The more stable compound makes NAC more bioavailable and therefore easier for your body to absorb. Taking acetylcysteine can therefore effectively support the strength of your immune system in the long term (4).

Effect of dietary supplements in sports

Intense training can leave its mark on your body. Many athletes therefore turn to the intake of food-rich antioxidants to increase their performance, strengthen their immune system or effectively boost muscle regeneration, for example.

However, the performance-enhancing effect of antioxidants in sports is scientifically controversial.

A study by the University Hospital of Tübingen suggests that the positive effect of orally ingested antioxidants on reduced muscle damage and muscle fatigue has not been sufficiently investigated and therefore requires additional data analysis (6).

However, another study suggests that the intravenous intake of acetylcysteine has performance-enhancing effects. The subjects of this study showed increased endurance during cycling, as well as reduced muscle fatigue (5)

What are the possible side effects of taking NAC?

Your health should always come first. That is why we recommend that you always pay attention to the recommended dosage when taking NAC. You can find this in the package insert or in consultation with a specialist.

By following these guidelines, you can avoid side effects from NAC and minimise potential health risks for yourself.

You should always follow the recommended dosage and not exceed it.

However, scientific studies suggest that potential side effects or intolerances associated with NAC use have not been adequately researched and therefore require additional investigation (7).

Because of this, it is especially important to always follow the recommendations and guidelines for taking NAC. If you experience unpleasant side effects, we recommend that you talk to a doctor.

When and for whom is it useful to take NAC?

As you have already learned, acetylcysteine has different effects and can therefore be used for different purposes. Its antibacterial, antioxidant and expectorant functions make NAC a proven dietary supplement and medicine.

Taking NAC products depends on your individual needs or the intensity of your condition.

To strengthen the immune system, NAC products are generally suitable for everyone (4, 10). A strong and effective immune system is very beneficial for all people and can improve the quality of life of any person in the long term.

NAC preparations are available in various dosage forms. (Image source: Unsplash / Elsa Olofsson)

Taking NAC products is also useful for the treatment of medical conditions, such as respiratory diseases. If you suffer from a cough or sore throat, the expectorant and expectorant effects of acetylcysteine can effectively relieve your symptoms and contribute to the recovery process (2, 8).

What types of NAC are there?

Acetylcysteine is processed into powder and can therefore be purchased in various forms. So that you are sufficiently informed, we have summarised the decisive features of the different types of NAC products for you below.

Type Advantages Disadvantages
NAC capsules No taste, Long shelf life, Easy dosage Delayed effect, Difficult to take
NAC powder Self-dosing, Take with liquid, Fast effect Shorter shelf life, Unpleasant taste
NAC tablets Easy dosage, Easy storage, Long shelf life Difficult to take, Delayed effect

You can read about the details that are important in the various forms of administration of the different types of NAC products below.

NAC capsules

NAC capsules are a common form of acetylcysteine. These have the significant advantage over other forms of administration in that they have a long shelf life. Due to their packaging, contact of NAC capsules with the air is avoided and therefore the shelf life of the individual capsules is not negatively affected.

The capsule's wrapper protects you from unpleasant inherent tastes of the preparation.

However, NAC capsules also have some disadvantages that you should be aware of. After the capsule has arrived in your stomach, it takes a little time for it to dissolve. This causes a delay in the effect. In addition, the capsules must be swallowed in their solid form, which is not easy for everyone.

NAC powder

Powder is another popular form of NAC products. Because of its properties, you can dose it yourself. This has the advantage that you can take quantities of NAC that are adapted to your individual needs.

Taking NAC preparations can improve your quality of life (Image source: Unsplash / Radu Florin)

The loose form of the powder also makes it easy to take. You can mix the NAC powder with plenty of liquid and then drink it without making it difficult to swallow.

However, you may come into contact with the flavour of the preparation when taking it in this form. To avoid this, you can mix a small amount of your favourite juice into the liquid.

Taking NAC powder favours a quick effect, as it reaches your stomach immediately. Finally, keep in mind that NAC powder does not have the same shelf life as NAC capsules or tablets.

NAC tablets

In addition to capsules and powder, you can also buy NAC products in tablet form. These are very easy for you to dose and can be stored without any problems. The shelf life of NAC tablets is also significantly longer than that of the loose powder.

However, if you have difficulty swallowing, taking NAC tablets can be a little uncomfortable for you. Besides regular tablets, you can also buy lozenges and effervescent tablets.

How should NAC be dosed and taken?

With regard to the dosage, the various manufacturers tell you on the packaging of the NAC products in what quantities and at what time of day you should take them.

We recommend that you always follow these instructions so that you can achieve the best possible results from taking the product.

Acetylcysteine is not an essential substance for your body, which is why no deficiency symptoms can occur without taking NAC preparations.

If you are unsure about taking NAC, you can of course ask your doctor or pharmacist for competent advice.

What alternatives are there to NAC?

You can quickly recognise the advantages of an intact immune system, as they can fundamentally strengthen your quality of life and physical health.

To achieve the immune system boosting effect of NAC without taking this synthetic chemical compound, you can also purchase other preparations. The most popular products include:

  • L-glutathione preparations
  • Vitamin B, C and D preparations
  • Iron and zinc supplements

Of course, you can also strengthen your immune system by eating a balanced and healthy diet. In this way, you can effectively prevent the spread of unwanted pathogens. To make this decision easier for you, we have listed the most popular foods for a strong immune system below:

  • Broccoli
  • Nuts
  • Garlic
  • Lemons
  • Acerola

Of course, these are only recommendations for your inspiration. You should choose the right food based on your personal needs and preferences.

Image source: sweetlouise / unsplash

References (10)

1. Clemente Plaza, Noelia et al. “Effects of the Usage of l-Cysteine (l-Cys) on Human Health.” Molecules (Basel, Switzerland) vol. 23,3 575. 3 Mar. 2018, doi:10.3390/molecules23030575
Source

2. Santus, Pierachille et al. “Oxidative stress and respiratory system: pharmacological and clinical reappraisal of N-acetylcysteine.” COPD vol. 11,6 (2014): 705-17. doi:10.3109/15412555.2014.898040
Source

3. Stey, C et al. “The effect of oral N-acetylcysteine in chronic bronchitis: a quantitative systematic review.” The European respiratory journal vol. 16,2 (2000): 253-62. doi:10.1034/j.1399-3003.2000.16b12.x
Source

4. Rushworth, Gordon F, and Ian L Megson. “Existing and potential therapeutic uses for N-acetylcysteine: the need for conversion to intracellular glutathione for antioxidant benefits.” Pharmacology & therapeutics vol. 141,2 (2014): 150-9. doi:10.1016/j.pharmthera.2013.09.006
Source

5. Braakhuis, Andrea J, and Will G Hopkins. “Impact of Dietary Antioxidants on Sport Performance: A Review.” Sports medicine (Auckland, N.Z.) vol. 45,7 (2015): 939-55. doi:10.1007/s40279-015-0323-x
Source

6. Nieß AM, Striegel H, Hipp A, Hansel J, Simon P. "Zusätzliche Antioxidanziengabe im sport – sinnvoll oder unsinnig? Antioxidant supplementation in sports – sense or non-sense?" Deutsche Zeitschrift für Sportmedizin vol. 59,3 (2008)
Source

7. Rhodes, Kate, and Andrea Braakhuis. “Performance and Side Effects of Supplementation with N-Acetylcysteine: A Systematic Review and Meta-Analysis.” Sports medicine (Auckland, N.Z.) vol. 47,8 (2017): 1619-1636. doi:10.1007/s40279-017-0677-3
Source

8. Kalyuzhin OV. Effect of N-acetylcysteine on mucosal immunity of respiratory tract. Ter Arkh. 2018 Apr 19;90(3):89-95. doi: 10.26442/terarkh201890389-95. PMID: 30701862.
Source

9. Cazzola, Mario et al. “Influence of N-acetylcysteine on chronic bronchitis or COPD exacerbations: a meta-analysis.” European respiratory review : an official journal of the European Respiratory Society vol. 24,137 (2015): 451-61. doi:10.1183/16000617.00002215
Source

10. Yuval Samuni, Sara Goldstein, Olivia M. Dean, Michael Berk, The chemistry and biological activities of N-acetylcysteine, Biochimica et Biophysica Acta (BBA) - General Subjects, Volume 1830, Issue 8, 2013, Pages 4117-4129, ISSN 0304-4165, https://doi.org/10.1016/j.bbagen.2013.04.016 (http://www.sciencedirect.com/science/article/pii/S030441651300144X)
Source

Why you can trust me?

Wissenschaftlicher Artikel
Clemente Plaza, Noelia et al. “Effects of the Usage of l-Cysteine (l-Cys) on Human Health.” Molecules (Basel, Switzerland) vol. 23,3 575. 3 Mar. 2018, doi:10.3390/molecules23030575
Go to source
Wissenschaftlicher Artikel
Santus, Pierachille et al. “Oxidative stress and respiratory system: pharmacological and clinical reappraisal of N-acetylcysteine.” COPD vol. 11,6 (2014): 705-17. doi:10.3109/15412555.2014.898040
Go to source
Wissenschaftlicher Artikel
Stey, C et al. “The effect of oral N-acetylcysteine in chronic bronchitis: a quantitative systematic review.” The European respiratory journal vol. 16,2 (2000): 253-62. doi:10.1034/j.1399-3003.2000.16b12.x
Go to source
Wissenschaftlicher Artikel
Rushworth, Gordon F, and Ian L Megson. “Existing and potential therapeutic uses for N-acetylcysteine: the need for conversion to intracellular glutathione for antioxidant benefits.” Pharmacology & therapeutics vol. 141,2 (2014): 150-9. doi:10.1016/j.pharmthera.2013.09.006
Go to source
Wissenschaftliche Studie
Braakhuis, Andrea J, and Will G Hopkins. “Impact of Dietary Antioxidants on Sport Performance: A Review.” Sports medicine (Auckland, N.Z.) vol. 45,7 (2015): 939-55. doi:10.1007/s40279-015-0323-x
Go to source
Wissenschaftliche Studie
Nieß AM, Striegel H, Hipp A, Hansel J, Simon P. "Zusätzliche Antioxidanziengabe im sport – sinnvoll oder unsinnig? Antioxidant supplementation in sports – sense or non-sense?" Deutsche Zeitschrift für Sportmedizin vol. 59,3 (2008)
Go to source
Wissenschaftliche Metastudie
Rhodes, Kate, and Andrea Braakhuis. “Performance and Side Effects of Supplementation with N-Acetylcysteine: A Systematic Review and Meta-Analysis.” Sports medicine (Auckland, N.Z.) vol. 47,8 (2017): 1619-1636. doi:10.1007/s40279-017-0677-3
Go to source
Wissenschaftlicher Artikel
Kalyuzhin OV. Effect of N-acetylcysteine on mucosal immunity of respiratory tract. Ter Arkh. 2018 Apr 19;90(3):89-95. doi: 10.26442/terarkh201890389-95. PMID: 30701862.
Go to source
Wissenschaftliche Metastudie
Cazzola, Mario et al. “Influence of N-acetylcysteine on chronic bronchitis or COPD exacerbations: a meta-analysis.” European respiratory review : an official journal of the European Respiratory Society vol. 24,137 (2015): 451-61. doi:10.1183/16000617.00002215
Go to source
Wissenschaftlicher Artikel
Yuval Samuni, Sara Goldstein, Olivia M. Dean, Michael Berk, The chemistry and biological activities of N-acetylcysteine, Biochimica et Biophysica Acta (BBA) - General Subjects, Volume 1830, Issue 8, 2013, Pages 4117-4129, ISSN 0304-4165, https://doi.org/10.1016/j.bbagen.2013.04.016 (http://www.sciencedirect.com/science/article/pii/S030441651300144X)
Go to source
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