Blueberries Can Improve Artery Function
Michael Greger M.D. FACLM
on April 5, 2022
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If you eat blueberries week after week, you also get chronic benefits, in terms of reduced artery stiffness and a boost in your natural killer cells, which are one of your body’s natural first lines of defense against viral infections and cancer. How can blueberries have all these amazing effects if the anthocyanins—the blue pigments in blueberries purported to be the active ingredients—hardly even make it into our system? Indeed, women were given more than a cup of blueberries to eat, and the researchers couldn’t find hardly any in their bloodstream or flowing through their urine.
At 2:47 in my video, you can see a chart called a chromatogram. The spikes show all of the anthocyanin peaks in blueberries. Before eating blueberries, there is no sign of the pigments in the participants’ blood, which makes sense because they hadn’t been ingested. After one hour of eating them, however, you start to see the spikes appear, and, a few hours after that, they become a bit more distinct. All in all, though, just a few billionths of a gram per milliliter show up. So, “either anthocyanins are extremely potent and, therefore, active at low serum [parts-per-billion blood] concentrations…or their dietary occurrence or bioavailability has been underestimated.” Researchers decided to radioactively tag them and trace them throughout the body.
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