I take 15mg of melatonin at night. Tried astragalus about a year ago, two capsules as per label recommendation, got severe diarrhea. About three weeks later, tried again only one capsule this time, got severe diarrhea again so canned it. However, most of the herbs and supplements my late wife from the Indian sub-continent recommended to me have worked out well.
It is straightforward to rate antioxidants in terms of their ability to inhibit oxidation.
In terms of sheer inhibition of oxidation, I think Glutathione and SOD are going to come in way above melatonin, but I’m glad it works for you. It has some nasty hormonal effects and is a natural DHT inhibitor, which is often a good thing for people who are trying to control male pattern baldness, but it can cause side effects similar to something like Finasteride. Totally shut me down and messed me up something awful until I realized that it was the culprit lol
Have you tried NAC?