I did post a NAC use study for use with COVID some months back, but that described it helping reduce lung issues while having COVID, but had also mentioned that a 600 mg dose of just NAC could be used as a preventative dose for likely exposure occasions, while up to 2,400 mg could be used from supplements for more serious lung issues, if progressing into pneumonia or ARDS. However, this was for short-term use occasions.
Nestle is selling the combination of both NAC and glycine, as 600 mg each, as a daily amount. However, they also have two other supplements, to be bought separately, that complement the GlyNAC, one of which appears to greatly increase apoptosis of defective mitochondria. That particular supplement has Urolithin A in it (500 mg/day), which is a dose that was used in another study, showing its benefits.
Your posted study appears to mention that it NAC is helping defective cells survive - cells that are capable of devolving into cancer - that have otherwise been sidelined, but not cleared out by normal processes, in part, due to those processes having broken down, too. I can see how a substance could bring back to life both good and bad cells, largely due to revitalizing their mitochondria. However, the processes we have to eliminate problem mitochondria and cells should also be revitalized, and appear to be, from the nature of the GlyNAC study's tests showing glutathione being generated everywhere they tested.
Is it made less concerning by adding the glycine? The glycine is supposed to help convert the NAC, and this combination also made mice live 24% longer lives in a separate study. According to your posted study, 10% of normal aged mice used in the 24% longer life study should have had lung cancer, if GlyNAC, as opposed to just NAC-only (again, your study), caused problems with lung cancer. I will say that in the 24% longer life study, the mice got GlyNAC only when they entered old age, as opposed to being given it from conception (fed to mother at 40 mM concentration in all liquids) through to old age (40 mM concentration in all liquids), for just the NAC, in your study.
The GlyNAC longer life study:
“GlyNAC supplementation extends life span in mice (Equal parts glycine and NAC)”
https://freerepublic.com/focus/f-chat/4044707/posts
From the study this thread initially referenced (“GlyNAC improves multiple defects in aging to boost strength and cognition in older humans”):
“This study also answers the question of why GlyNAC is an improvement over supplementation with NAC alone. GSH synthesis requires two biochemical steps – in the first step cysteine is added to glutamic acid to form the intermediate glutamylcysteine, and in the second step glycine is added to glutamylcysteine to form GSH. Via translational studies in aged mice, we discovered and reported that GSH adequacy is critically important for optimal and efficient mitochondrial fatty-acid oxidation (MFO) in rodents and OA. Because the impact of longer duration of supplementing GlyNAC in OA was unknown, we conducted a 36-week open-label trial to test whether supplementing GlyNAC for 24-weeks in OA could improve or correct age-associated GSH deficiency, OxS, impaired MFO, inflammation, endothelial dysfunction, insulin resistance, muscle protein loss, and body composition, and whether this could impact cognitive function, gait speed, muscle strength, and exercise capacity. The trial also assessed whether any accrued benefits would decline after stopping GlyNAC for 12 weeks.”
As stated immediately above, cysteine is added to one step, with glutamic acid, then the glycine is added to a second needed step, with glutamylcysteine, which is what creates the final end product needed in all cells to keep their glutathione levels good. Young people can generate the needed glycine and cysteine an normal amounts so adding more cysteine may not be helpful, but in your study, young mice fed NAC-only from conception to young adulthood did already have more problems than the control mice never fed NAC, so I'd say adding cysteine alone to young people should be limited to “as needed” does, such as when NAC is administered for breaking up phlegm in cold remedies, to be safe.
In light of your study, would I chronically take NAC by itself, without glycine? No, again, to be safe. No study speaks to what NAC, not used for a glutathione reaction, does in the body. Does it build up? Does it get used in a process that is going bad? It would preliminarily seem that, at least by itself, it stops a normal process that gets rid of cells or their mitochondria that are beginning to go bad, but there were big differences between the studies and what was given and for how long. In that light, I still feel comfortable with the GlyNAC for myself and my wife and others, in the generally low dose of 600 mg glycine and 600 mg NAC, administered at the same time.
Thank you very much for the extra information in reply! I will try 600 mg of NAC and 1000 mg of glycine (pills to keep it more simple than measuring powder). The choice for glycine capsules at the sites that I looked at were between 500 mg and 1000 mg. Will see if my stomach will tolerate 1000 mg. Might take both just before bedtime, well after the last meal. Getting some niacin 500 mg caps, too.
I’m over 60 with blood pressure, inflammation, bloating, breathing and related problems. Going to try that for six months while quitting smoking (again) and gradually increasing exercise (breathing exercises, increasingly faster walking, pushups, dumbbells, abdominals, hips, etc.). Off and on lifelong exercise and smoking here. ;) Lost a lot of weight over the past few years, but some gut fat remains. The pulsating, painful blob in the middle must go.
And yeah, there’s the risk in what I’m doing, but I won’t blame you. If a clot plugs something up here, it’s all mine. If it doesn’t, I might become a PT animal again (done before several times, including as a soldier, rugger, fighter, etc., and just because, at times).
Thanks again. Maybe you’ll also find this to be interesting from the report that you posted information about. :)
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC8002905/
Glycine and N‐acetylcysteine (GlyNAC) supplementation in older adults improves glutathione deficiency, oxidative stress, mitochondrial dysfunction, inflammation, insulin resistance, endothelial dysfunction, genotoxicity, muscle strength, and cognition: Results of a pilot clinical trial
Under “4.10. Genomic damage and cancer risk”
“...However, whether GlyNAC can lower cancer risk in humans is unknown and needs to be evaluated in future studies. Metabolic profiling has identified a possible role for glycine in cancer cell proliferation, 75 *but glycine supplementation was found to prevent the development of hepatic tumors 76 in rats, inhibit the growth of melanoma tumors 77 in mice, and to also inhibit tumor growth in a mammary adenocarcinoma cell line. 78 A more recent study from the National Institutes of Health (NIH) Intervention Testing Program reported that mice supplemented with glycine lived 4%–6% longer and had a lower presence of pulmonary adenocarcinoma.* 79”
[”*” emphasis mine. And remember that many different kinds of cancer are very different from one another, and so far, require different kinds of approaches.]