I’ve being wondering how does probiotics and fiber help with lack of serotonin.
Man I can’t speak to that specifically, but I can’t stress enough how lifestyle/diet & nutrition changes made a difference in my depression & anxiety. Having a healthy gut biome definitely does help.
In the time of modern medicine, doctors have been looking for something that will make their patients feel better. They’ve found it! The answer is not just a single bacteria or even bugs - but rather an entire ecosystem in which these microbes live together as one unit and provide us with immense benefits.
A healthy gut microbiome means more than serotonin; certain species produce either negative (like Clostridia) or positive effects when interacted with antidepressants such as Bifidobacteria digests lactose so you don’t get diarrhoea from consuming dairy products.
As others have said, it’s more about overall composition through lifestyle, diet and environment that influence this. That being said the metabolites of the microbes not only produce things like serotonin in the gut, but provide precursors for the synthesis of GABA, serotonin, and dopamine in the brain. An essential mediator for transport of ‘Information’ and metabolite within the gut-brain axis is the vagus nerve
This item states “There was also evidence pro-inflammatory diets were linked with depression.” https://theconversation.com/clear-evidence-for-a-link-between-pro-inflammatory-diets-and-27-chronic-diseases-heres-how-you-can-eat-better-158451
Increasing serotonin is only part of depression treatment. If serotonin was all you needed, then serotonin precursor supplements and amino acids would be enough. SSRIs also act on other targets and not just serotonin transporters.
Think about it like this, serotonin is just the “message” but for healthy neuronal activity you need a messenger and receiver too! If either of those are not functioning, then it doesn’t matter how many “messages” you send!
So how does gut health really impact the brain? Well it’s an unanswered question but we know some details:
Bad gut health causes immune responses which raises immune activation elsewhere too like at the blood brain barrier (where monocytes gather to communicate with microglia inside the brain)
A raised immune system can activate microglia in the brain (microglia have the same embryological lineage as other monocytes like macrophages)
Activated microglia can and will prune away synapses (our messenger and receivers)
So pruning synapses via immune activity probably contributes more to depression than low serotonin. In fact, low serotonin is probably a consequence of pruned synapses because you can’t release serotonin without synapses!
If your synapses are being eaten up, even just a little, then your brain has a weakened capacity to process thoughts, moods, and emotions, all parts of depression.
So keep your gut healthy or your immune system will hurt you.
So eat leafy greens and less processed foods, for starters.
Serotonin is a hormone produced in the mucosa of the small intestine and is vital for our autonomic nervous system. This is because serotonin is a neurotransmitter - a messenger from brain to our body via the central nervous system. It influences our peripheral circulation which then regulate our mood and in this case ease up depression.
Typically anti-depressant improves serotonin level - but it is always better for the body to produce its own serotonin.
You might find this paper of interest: https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4809873/ it talks about how certain foods especially grains can cause tiny holes in the gut which allows food particles to reach into the brain and this causes mental health problems