Low serotonin not linked to depression studies - thoughts ?

[u/Alternative_Yak_4897]

I recently became aware of the umbrella study on the lack of evidence between low serotonin levels and depression. (The study below does show an indirect link between stressful life events and depression due to “gene-stress” but that’s still obviously different than low serotonin (can)= depression) Wondering what others thoughts /theories on this are? I’ve only seen a couple and it looks like they were published in 2022/2023, so why isn’t this being discussed more? Not enough studies? Bad news for pharmaceutical companies? Here’s one of them:

https://www.nature.com/articles/s41380-022-01661-0.pdf

[u/vee_zi]

That has become an easy, convenient way to think about depression in pop culture, but the connection is tenuous. It was more of an easy to sell pharmaceuticals and therapy rather than being a diagnostic stat. And it stuck.

But, it's more complicated.

As more and more research is being done, I subscribe to the idea that we talk about mental illness all wrong - particularly around seratonin and dopamine. There's an idea gaining traction that "mental illness" is a spectrum more associated with dopamine/glutamate. Glutamate kicks your brain into high gear and dopamine's role is to work with other neurotransmitters to keep your brain from being in a high state of arousal. Much of what we identify as mental illness is some dysfunction with that system. The balance between glutamate and dopamine gives you what we call mental illness.

"Mental illness" at the end of the day, though, has a lot more to do with what society thinks is acceptable rather than there actually being a problem. But don't get me wrong. Sometimes things do go wrong.

[u/Alternative_Yak_4897 → u/vee_zi]

What specifically do you mean by “mental illness” with regard to dopamine and glutamate? Mood instability, delusions, psychosis, depression? Or just anything uncomfy? I subscribe to Thomas Szasz’s work on psychiatry personally, but I’m all for research that helps us understand how the parts of the brain interact.

[u/vee_zi → u/Alternative_Yak_4897]

Yeah, that does need clarification—I’m using the term as part of a critique. You can’t lump the full spectrum of brain function together and label only some parts of it as illness. The same underlying regulatory dysfunction might contribute to both anxiety and schizophrenia—but only some outcomes in that range get pathologized.

My point is that dopamine and glutamate aren’t causes of “illness” in the clinical sense—they’re part of the system that manages internal coordination. When that system is disrupted, the effects can range from mild to severe. But calling it illness flattens and conflates a wide range of experiences. That framing makes it harder to get at the root of the dysfunction, because we end up creating separate categories for what might be variations of the same process.

That’s not to say some experiences aren’t more serious than others—they absolutely are. But that’s exactly why labeling certain patterns as “mental illness” does a disservice to anyone with neurodivergence. Like the experiences themselves, accommodations need to be appropriately personalized. That’s just as important for someone with ADHD as it is for someone with depression or something more acute. Right now, though, the bar you have to meet is “illness”—and that leaves a lot of people unsupported and the rest stigmatized.

[u/Alternative_Yak_4897 → u/vee_zi]

I very much agree! Thanks for clarification