A recent study by neurobiologists at Oxford University has provided exciting evidence that such a link does indeed exist - and it has implications for treating anxiety and stress-related conditions naturally.
What are pre- and pro- biotics? Pre-biotics are non-digestible carbohydrates (often referred to as "soluble fibre") that can be found in many foods such as artichokes, leeks, asparagus, legumes and oats. Supplements such as metamucil and benefibre are also essentially a pre-biotic and can be useful. Pro-biotics are beneficial bacteria that reside in our intestines. There are hundreds of types, and they have been proven over many years to be a vital part of our health and immune system.
Pro-biotics feed off pre-biotics in the gut, and are known to "modulate the processing of information that is strongly linked to anxiety and depression, and influences the neuroendocrine stress response." (Schmidt et al, 2014) What, then, is the link between the brain, the gut, and anxiety?
The Oxford study tested the amount of the stress hormone cortisol present the saliva of volunteers when put under stressful situations. There were two groups of volunteers - one undergoing treatment with a prebiotic, and the other undergoing treatment with a placebo. The result was a significantly lower stress response in the treated volunteers.
While this result can't be seen as definitive or a replacement to existing treatments for anxiety and other stress-related conditions, it does suggest that pre- and pro- biotics should be utilised in any wholistic treatment of anxiety and stress-related conditions.
As well as the added benefits of regularity, lower cholesterol and lower blood pressure, a small (half-cup) breakfast of oats, natural muesli with added psyllium husks (from a health food store), yoghurt or a pre-biotic drink might just help to relieve some of your feelings of stress and anxiety.
Prebiotic intake reduces the waking cortisol response and alters emotional bias in healthy volunteers, (2014) Kristin Schmidt, Philip J. Cowen, Catherine J. Harmer, George Tzortzis, Steven Errington and Philip W. J. Burnet; Department of Psychiatry, University of Oxford
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