Probiotics are live microorganisms that, when ingested in sufficient quantities, provide health benefits to the host. Although probiotics are mostly associated with gut health, recent research suggests that they can also improve brain health.
The gut and the brain are connected through the gut-brain axis. This is a bi-directional communication pathway that involves neural, endocrine, and immune signaling. The gut microbiota, which is the collection of microorganisms that inhabit the gut, plays a crucial role in regulating the gut-brain axis. This means, balancing the gut microbiota with probiotics can have a positive impact on brain function.
Several studies have shown that probiotics can improve mood and cognitive function. For instance, a randomized, double-blind, placebo-controlled trial conducted on 40 healthy volunteers found that daily consumption of a probiotic mix for four weeks improved cognitive processing and reduced negative thoughts and rumination. Another study on 70 healthy adults showed that a multispecies probiotic supplement improved memory, attention, and stress coping compared to placebo.
Probiotics may even be beneficial for people with neurological disorders. For example, a study on patients with Alzheimer's disease found that a probiotic supplement containing Lactobacillus acidophilus, Bifidobacterium lactis, Lactobacillus fermentum, and Lactococcus lactis improved cognitive function and reduced inflammation. Another study on patients with multiple sclerosis showed that a probiotic supplement containing Lactobacillus plantarum improved quality of life and reduced inflammation.
The mechanisms by which probiotics exert their brain benefits are not fully understood, but they may involve the modulation of neurotransmitters, the reduction of inflammation, the production of short-chain fatty acids, and the improvement of gut permeability.
While probiotics are emerging as a promising avenue for improving brain health, more research is needed to fully understand their mechanisms of action and optimal dosage and duration, but their safety and low cost make them an attractive option for promoting mental wellbeing.
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