Chemically made supplements of methionine, melatonin, NAC, choline are not low deuterium. As such, they are harmful. Most of these supplements are chemically made. Biologically made methionine, NAC, melatonin, choline are low in deuterium Tristan Scott: "That's so fascinating in terms of the synthetic. I hate when a lot of these, maybe it's more the Fitness Bros, or the 'Show me the study' guys are like, 'Well, there's no difference between synthetic [methionine] and natural components.'" Dr. Stephanie Seneff: "That is not true." Tristan Scott: "Now it's like, 'Well, we have here some proof that actually there is.' Why is there actually a difference? Is it just because they don't consider those deuterium-depletion steps that our innate biology has built in?" Dr. Stephanie Seneff: "Precisely, yeah. First of all I want to say that melatonin has the same problem. And N-acetylcysteine does, too. So the acetyl in N-acetylcysteine, that's going to be low deuterium if it comes from the gut microbes, but if it's made synthetically it won't. So if you're taking a supplement N-acetylcysteine, no guarantee that that acetyl is going to be low deuterium. "And melatonin, melatonin has both an acetyl and a methyl attached to it. It starts out as tryptophan, which of course comes out of the shikimate pathway. Tryptophan gets turned into serotonin, which is another neurotransmitter. And then serotonin gets turned into melatonin, and when you do that you add a methyl and an acetyl. Both of them are going to be low deuterium if they came from a biological source. "But if you eat a methionine that's made in the chemistry lab, which it typically is, that's how you can do it cheaply. […] Imagine growing microbes and having to purify the methionine that's in there with all the other stuff that's there, right? Or the melatonin. That's a lot of work. So you'd rather just make it chemically. You can get a pure supply more easily if you don't have to deal with all the biological life that might be mixed up in there and cause problems. So most of these supplements are chemically made, and they're not going to be good, so I don't recommend any of these supplements that are going to have these. "Choline is another one. Choline is going to be low deuterium if it comes from a biological source. But if they're making in the chemistry lab, forget it. It's not good for you. So I think people are loading up on supplements that are actually hurting them because they're not supplying the low deuterium resource that would have happened if it had been biological. "Now I need to explain why that's the case, because it's super fascinating. I figured it out based on a paper that was written in the 1960s. […] That paper showed […] that the gas that was made by these [gut] microbes, hydrogen gas, H₂, had 80% of the deuterium gone. It was down by a factor of five. 80% gone. So that becomes a really good source of low deuterium hydrogen. And then the microbes are very careful to make sure […]" Dr. Stephanie Seneff with npub1yd2h2lrwchshvm46jq7auh65tjkxmgnapkavh7tjtqq07kknupxsa980tv @ 58:17–01:01:20 (posted 2023-12-05) https://youtu.be/LaU2i0T5FWY&t=3497