Something new I found out - there is something called mitophagy and things like fasting or pomegranate induce it. It causes your system to destroy malfunctioning parts of mitochondria and rebuild them. It's autophagy targeted at mitochondria. They say malfunctioning mitophagy is found in alzheimer's, diabetes, complications, artherosclerosis, cancer... and FATIGUE. Some of the things that can induce mitophagy include tea (catechinic acid), pomegranate (urolithin), quercetin (apples), and resveratrol (grapes, wine, blueberries, cocoa...). Melatonin is also listed but the comments say it PROTECTS the mitochondria, so maybe something you do to protect the newly rebuilt mitochondria from a quick demise. Like the astaxanthin I mentioned above (another protectant). There are supplements to induce mitophagy now with an ingredient called robuvit, from oak:
https://www.iherb.com/pr/swanson-robuvit-french-oak-wood-extract-200-mg-30-veggie-caps/117983
https://www.iherb.com/pr/life-extension-energy-renew-200-mg-30-vegetarian-capsules/62213
urolithin (from oak, pomegranate):
https://www.iherb.com/pr/super-nutrition-urolithin-a-250-mg-60-liquid-veggie-capsules/142031
general autophagy (turns out it uses luteolin):
https://www.iherb.com/pr/life-extension-geroprotect-autophagy-renew-30-vegetarian-capsules/106215
and, what I take, luteolin from celery due to it normalizes my high blood pressure):
https://www.iherb.com/pr/nutricost-luteolin-100-mg-120-capsules/129419
(I'm not full of energy, but that trudging through life after covid is gone.).
Caveat: autophagy protects against cancer, unless you've already got it well-established - then it protects the deranged cancer cells.
One of the interesting tidbits I found (a non sequitor) is this: The intestinal epithelium is one of the most rapidly self-renewing tissues and needs a great amount of energy. Mitophagy, which can mediate the clearance of damaged mitochondria before they cause activation of cell death, is crucial for the homeostasis of the intestinal epithelium [
8]. I have been having gut issues and have been concerned because my sensitive gut lining sometimes limits the things I could take for health. It looks like a sensitive gut lining is an early sign of mitrochondrial decline. It made me wonder if gut lining sensitivities are a big problem here?