Tea, coffee and dark chocolate

Polyphenols: the natural chemicals that could give you a small waist,
healthy heart and low blood pressure

Can the compound found in plants slow the ageing process and help
tackle Alzheimer's? Food writer Giulia Crouch finds out

There's a new buzzword in town when it comes to health: polyphenols.
While scientists have been investigating the plant compounds for
years, the term has now caught the public imagination - and for good
reason.

A growing body of evidence shows that eating a diet high in these
clever natural chemicals offers numerous health benefits, improving
everything from heart and metabolic health to lowering the risk of
neurodegenerative diseases, such as Alzheimer's.
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Polyphenols are a group of phytonutrients (though the terms are often
and erroneously used interchangeably), naturally occurring chemicals
in plants that help to protect them in nature from threats such as
insects and UV light, and, as it turns out, also help to protect us
when we eat them

They are found in high concentrations in fruits and vegetables with
deep or vivid colours such as beetroot, blackberries, black olives,
very red tomatoes and dark, leafy greens. As well as protecting the
plant, phytonutrients - including polyphenols - also provide it with a
strong pigment. The same is true for strong tastes: the more
cough-inducing an extra virgin olive oil, the higher the likely
concentration of polyphenols. Tea, coffee and dark chocolate are
excellent sources.

There are thousands of types of phytonutrients – we haven’t discovered
them all - such as resveratrol in red wine, ellagic acid in walnuts
and catechins in tea. And single ingredients have multiple
phytonutrients - tomatoes contain polyphenols (flavonoids and
flavanones) as well as carotenoids (lycopene, phytoene and beta
carotene).

Trials have shown they all do different things for our health.

https://www.theguardian.com/science/2025/jan/04/polyphenols-the-natural-chemicals-that-could-give-you-a-small-waist-healthy-heart-and-low-blood-pressure