Blueberries are one of the richest sources of polyphenols — plant compounds that act as powerful prebiotics, selectively feeding beneficial gut bacteria. Their deep blue-purple colour comes from anthocyanins, a class of polyphenol that reaches the colon largely intact and is fermented by gut bacteria into anti-inflammatory short-chain fatty acids.
Why it matters
Polyphenol Powerhouse
One of the highest polyphenol densities of any commonly eaten fruit.
Feeds Beneficial Bacteria
Anthocyanins reach the colon intact and selectively feed Bifidobacterium.
Reduces Inflammation
Polyphenol fermentation produces anti-inflammatory short-chain fatty acids.
Brain Health
Regular consumption is linked to improved memory and cognitive function in older adults.
How to eat it
A handful (80-100g) daily is all you need. Add to overnight oats with kefir, blend into smoothies, or eat fresh with full-fat yogurt. Frozen blueberries retain their polyphenol content and are often more economical. Wild blueberries have a higher polyphenol density than cultivated varieties.
Regular blueberry consumption has been shown to increase Bifidobacterium populations by up to 33% and reduce markers of gut inflammation — effects driven primarily by their polyphenol content.
Source: Vendrame et al., Journal of Nutrition, 2011
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