Related to this, it's been shown that Long Covid sufferers have low levels of circulating serotonin due to viral inflammation downregulating the gut intake of tryptophan (serotonin's precursor) and is also (I believe) correlated with IL-6 similar to the article. [1]
Tryptophan is the only way your body can produce serotonin, and if you're not getting serotonin that is a problem and can cause depression, fatigue, irritability, brain fog, brain zaps, etc.
The cool thing is there's a workaround: The same paper also found that if you supplement with Hydrolyzed protein (basically pre-digested protein, you can get it off Amazon) the tryptophan variant therein uses a different cellular uptake pathway which is not downregulated. This type of tryptophan is not generally found in food, so it's not like you could just eat a bunch of turkey instead.
I tried it and I'll be damned, it worked. This is not medical advice btw, just sharing what worked for me. You have to take it very very slowly because your brain, having been serotonin-starved for years, will have a very, VERY low tolerance, so even though your body rate-limits serotonin production, even the "normal" amount is a big disruption and you can still induce Serotonin Syndrome if you're not careful. I take no more than about a 1/4 serving every other day.
Also, goes without saying but DO NOT combine with SSRIs / MAOIs, or anything else that modulates serotonin.
It's never a good idea to make definitive statements like this from a single unreplicated study, especially when it has serious methodological problems.
I realize you're probably just trying to help, but:
A) I tested this on myself with results which are consistent with theirs and which would be unexpected if their conclusions were off-base, which is why I'm comfortable making these statements.
B) There is no treatment for Long Covid and people have been suffering for years without any recourse. If my comment helps one person searching the Internet then I don't think it's a bad idea.
Tryptophan is the only way your body can produce serotonin, and if you're not getting serotonin that is a problem and can cause depression, fatigue, irritability, brain fog, brain zaps, etc.
The cool thing is there's a workaround: The same paper also found that if you supplement with Hydrolyzed protein (basically pre-digested protein, you can get it off Amazon) the tryptophan variant therein uses a different cellular uptake pathway which is not downregulated. This type of tryptophan is not generally found in food, so it's not like you could just eat a bunch of turkey instead.
I tried it and I'll be damned, it worked. This is not medical advice btw, just sharing what worked for me. You have to take it very very slowly because your brain, having been serotonin-starved for years, will have a very, VERY low tolerance, so even though your body rate-limits serotonin production, even the "normal" amount is a big disruption and you can still induce Serotonin Syndrome if you're not careful. I take no more than about a 1/4 serving every other day.
Also, goes without saying but DO NOT combine with SSRIs / MAOIs, or anything else that modulates serotonin.
[1] https://www.cell.com/cell/fulltext/S0092-8674(23)01034-6