The facts about anthocyanin pigments that make some fruits and vegetables blue and purple, and how they benefit your health; and in particular, artery function.
This excerpt has been taken from the transcript of this video.
For example, if you give someone a big blueberry smoothie containing the amount of anthocyanins in a cup and a half of wild blueberries, you get a nice spike in arterial function that lasts a couple hours. Thus, the higher maximum forearm blood flow in the forbidden rice vinegar intake group might be attributed to an additional or synergistic effect of anthocyanin with the acetate. But it could also just be the antioxidant power of anthocyanins, in which case balsamic vinegar, which is made from red wine, may have a similar effect, as it was shown to have remarkably higher free radical scavenging activity compared to rice vinegar.
Enough to counter the artery-constricting effects of a high fat meal? We’ve known for nearly 20 years that a single high fat meal – Sausage and Egg McMuffins with deep fried hash browns – can cripple our artery function, cutting the ability of our arteries to dilate normally in half, within hours of it going into our mouths, compared to Frosted Flakes. Even with that massive, unhealthy sugar load, there was no effect on the arteries, because there was no fat. And not just animal fat; a quarter cup of safflower oil had a similar effect. In fact, the very first study to show how bad fat was for our arteries basically dripped highly refined soybean oil into people’s veins. But extra virgin olive oil isn’t refined. We know some whole food sources of plant fat, such as nuts, actually improve artery function, whereas oils, including olive oil, worsen function, but they didn’t specify extra virgin here. You can see, smell, and taste the phytonutrients still left in extra virgin olive oil—are they enough to maintain arterial function? No, a significant drop in artery function within three hours of eating whole grain bread dipped in extra virgin olive oil. And the more fat in their blood, the worse their arteries did.
Ah, but what if you ate the same meal but added balsamic vinegar on a salad. That seemed to protect the arteries from the effects of the fat. Now, balsamic vinegar is a product of red wine. Would you get the same benefits just drinking a glass of red wine? No. No improvement in arterial function after red wine. Why does balsamic vinegar work, but red wine not? Maybe it’s because the red wine lacks the benefits of the acetic acid in vinegar or, maybe it’s because the vinegar lacks the negative effects of the alcohol. And a third option might be that it was the salad ingredients, and had nothing to do with the vinegar. To figure out this puzzle, all we’d have to do is…. test non-alcoholic wine. And non-alcoholic red wine worked! So, maybe it was the grapes in balsamic vinegar, not the acetic acid. And indeed, if you eat a cup and a quarter of seeded and seedless red, green, and blue-black grapes with your Sausage and Egg McMuffin, you can blunt the crippling of your arteries. So, plants and their products may provide protection against the direct impairment in endothelial function, unless those products are oil or alcohol.
To see any graphs, charts, graphics, images, and quotes to which Dr. Greger may be referring, watch the above video. This is just an approximation of the audio contributed by Katie Schloer.