In our effort to keep you informed of strategies you can employ on your own to help support better breathing, we have brought to your attention nutritional supplements that are helpful to address nutrient depletion brought on by smoking/lung disease as well as supplements that have been shown to improve exercise tolerance/performance among people with COPD and other chronic conditions.
One such nutrient that we haven’t written about yet is an ingredient called N-Acetylcysteine (otherwise known as NAC). NAC is an amino acid that helps the human body produce a powerful antioxidant called glutathione and has antioxidant properties of its own. WebMD has a pretty decent overview of NAC including known medication interactions and side effects that you can view by clicking here.
In a study published in the August 2009 edition of Chest, the journal of record for the American College of Chest Physicians, a group of researchers reported significant improvements in exercise tolerance and lung function among COPD patients who received 1,200 mg of N-Acetylcysteine daily for 6 weeks. (Stav D, Raz M. Effect of N-acetylcysteine on air trapping in COPD: a randomized placebo-controlled study. Chest. 2009 Aug; 136(2):381-6)
The study involved 24 former smokers with COPD. These subjects were divided into two groups of 12. One group received a placebo for six weeks while the other received 1,200 mg daily of NAC. Both groups performed cycle ergonometer exercise capacity and lung function tests prior to the commencement of supplement use, and again at the end of the six week NAC dosing period. Both groups then underwent a 2 week flush out period where NAC was not used by any study subject before they reversed roles for another 6 week period (the group that had taken the placebo now took NAC and vice versa – in scientific terms this is called a crossover study).
The results were clear and unambiguous. Each group that used the NAC experienced increased exercise capacity post-dosage - whether expressed in terms of exercise endurance time, inspiratory capacity (IC), or forced vital capacity (FVC). These benefits were observed post-exercise and to a lesser extent when the patient was at rest prior to exercise.
The researchers surmise that NAC helps reduce a phenomenon known as “air trapping” in the lungs. In this way, the researchers suggest that NAC helps improve the performance of respiratory muscles and limbs (hence creating less demand for oxygen by these muscles) and in reducing inflammation (acting as an antioxidant to neutralize inflammation-producing free radicals created during exercise).
Air trapping occurs most often during vigorous effort and is common in COPD patients. Essentially, air trapping is when the lungs cannot expire forcefully enough of the air already used by your body and therefore cannot take in enough new air to provide the body with adequate oxygen for the increased level of activity. When air trapping occurs it creates an event in your body that doctors call dynamic hyperinflation that makes you feel like you can’t breathe in enough new air (but ironically, it is caused by the presence of too much old/used air in your lungs).
As an aside, another proven method respiratory care professionals use for reducing trapped air in your lungs is a breathing technique called pursed lip breathing. It’s highly effective and easy to learn. We’ve posted a pictorial demonstration of pursed lip breathing on our e-letter web site. Click here to view. You can also find a variety of text descriptions and pictorial/video demonstrations on the web by searching on the term “pursed lip breathing”.
For those of you with COPD or chronic shortness of breath who are engaged in an active exercise program or considering starting one, we suggest you consider the results of this research study and discuss with your doctor whether NAC might be helpful for you. NAC is available typically in 600 mg daily dosage levels in retail stores and online. If you decide to try NAC, remember the research study noted in this post was conducted using 1,200 mg/day. The researchers noted that previous studies that utilized 600 mg daily dosage did not show the same levels of improvement.
No comments:
Post a Comment