Anthocyanins

Polyphenols

The red, purple and blue pigments. They are what color blueberries, red cabbage and black rice.

Color is the signal: the darker it is right to the core, the more there is.

Effects and benefits

The pigments of blueberries, red cabbage and black rice act on your arteries within hours: in trials, a serving of blueberries improved their flexibility two hours later, and a cup a day for six months kept the effect. The microbiota does the rest of the work.

Anthocyanins change color with acidity: red in acid, purple at neutral, blue toward alkaline. That is why red cabbage turns blue with baking soda and pink with vinegar.

Their best-measured effect concerns blood vessels. In a controlled trial, blueberry drinks improved dilation of the arm artery one to two hours later, the more so at higher doses (Rodriguez-Mateos et al., 2013). In another, a cup of blueberries a day for six months improved arterial flexibility and HDL cholesterol in overweight adults (Curtis et al., 2019).

Barely 1% reaches the blood as is. The rest reaches the colon, where bacteria cut them into small phenolic acids, such as protocatechuic acid, which then circulate for hours: a good part of the effect probably goes through them (Czank et al., 2013).

Observational studies associate regular berry consumption with slower memory decline in older women (Devore et al., 2012): an association, not proof, but it launched many trials.

Sources: Rodriguez-Mateos et al., AJCN, 2013 · Curtis et al., AJCN, 2019 · Czank et al., AJCN, 2013 · Devore et al., Ann Neurol, 2012

Anthocyanins

Effects and benefits

Where to find it (34)

Also, in smaller amounts (101)