Miso is a fermented soybean paste that has been a cornerstone of Japanese cuisine and traditional medicine for over 1,000 years. The fermentation process — using Aspergillus oryzae mould — produces a rich array of live beneficial bacteria, digestive enzymes, B vitamins, and bioavailable amino acids. White miso is milder and fermented for weeks; red miso is aged for months and significantly more intense.
Why it matters
Live Beneficial Bacteria
Rich in Aspergillus oryzae and Lactobacillus strains that directly seed the gut.
Umami Amino Acids
Fermentation produces bioavailable glutamine — critical for gut lining repair.
B Vitamin Source
Miso is one of the few plant sources of Vitamin B12 — important for nerve function.
Isoflavones
Soy isoflavones support hormone balance and have anti-cancer properties.
How to eat it
Never boil miso — heat above 70°C destroys the live cultures. Stir into soups after removing from the heat, blend into dressings, or use as a marinade. A teaspoon dissolved in warm water is a simple, powerful daily gut tonic. One tablespoon of miso paste provides roughly a billion CFU of beneficial bacteria.
Regular miso consumption is associated with lower rates of gastric cancer in Japanese epidemiological studies, and miso's isoflavones have been shown to support oestrogen balance and reduce menopausal symptoms.
Source: Watanabe et al., Japanese Journal of Clinical Oncology, 1984
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