The Gut-Brain Connection
Japanese scientists first demonstrated the link between gut microorganisms and the nervous system in 2004, with a study in mice. Since then, studies in animals have demonstrated probiotics can improve symptoms of anxiety, stress, depression, chronic fatigue, autism, Alzheimer's, and vascular dementia. But the real test of probiotics is whether they can achieve similar results in humans. In the review, the researchers presented a number of studies showing probiotics, either in foods or as supplements, can significantly improve human brain function compared to placebo. For example, probiotics helped:- Improve mood in healthy volunteers.
- Decrease anxiety symptoms.
- Reduce psychological distress, depression and anger or hostility.
- Diminish negative thoughts associated with a sad mood.
- Improve depression, anxiety, and stress scores.
- Relieve stress in healthy medical students prior to sitting for their exams as measured by a reduction in salivary cortisol and physical symptoms of stress.