Flashback Friday: The Benefits of Açai vs. Blueberries for Artery Function

Below is an approximation of this video’s audio content. To see any graphs, charts, graphics, images, and quotes to which Dr. Greger may be referring, watch the above video.

“Plant-based diets…have been found to reduce the risk of” some of our leading causes of death and disability. “Studies have shown that the longest living and least dementia-prone populations subsist on plant-based diets…” So, why focus on just this one plant for brain health and performance—açai berries? Well, “foods rich in polyphenols [appear to] improve brain health,” and açai berries have lots of polyphenols and antioxidants; so, maybe they’d help.

But, if you’re just looking at polyphenols, there are over a dozen foods that have more per serving, and it doesn’t have to be black elderberry. Regular fruits, like plums, have more; a few spoonfuls of flax seeds, a few squares of dark chocolate, or even just a cup of coffee, has more.

In terms of antioxidants, yes, açai berries may have ten times more antioxidant content than more typical fruits, like peaches and papayas; five times more than strawberries—but comparable to blackberries. In fact, blackberries appear to have even more antioxidants, and are cheaper and more widely available.

Ah, but açai berries don’t just have potential brain benefits—for example, protecting the lungs against “harm induced by cigarette smoke.” But you all remember that study, right? That’s the one where “addition of açai [berries] to cigarettes has a protective effect against emphysema in [smoking] mice.” That’s not very helpful. There’s this long list of impressive-looking benefits, until you dig a little deeper.

For example, I was excited to see “reduction of coronary disease risk due to [a] vasodilation effect,” but less excited when I pulled the study, and found out that they were talking about a “vasodilator effect…in [the] mesenteric vascular bed of the rat.” But, there hadn’t been any studies on açai berries and artery function in humans, until now.

Give some overweight men a smoothie containing about two-thirds of a cup of frozen açai pulp, and a half a banana, versus an artificially-colored placebo smoothie with the banana but no açai; you get a significant improvement in artery function within two hours of consumption, which lasts at least for six hours. That one- or two-point bump is clinically significant. Those walking around with just a point higher go on to have 13% fewer cardiovascular events, like fatal heart attacks.

You can get the same effect from wild blueberries, though, about a point-and-a-half bump two hours after wild blueberry consumption—an effect peaking and plateauing at about one-and-a-half cups of blueberries, with two-and-a-half or three-and-a-half cups showing no further benefits.

What about cooked blueberries? Here’s the same wild blueberry drink effect we saw before. But what if you baked the blueberries into a bun, like a blueberry muffin? Same dramatic improvement in artery function.

Cocoa can do it, too. One tablespoon of cocoa gets you about a point, and two tablespoons is like a whopping four points—that’s like double the berries.

One-and-a-quarter cups worth of multicolored grapes gave a nice boost in artery function, but enough to counter an “acute endothelial insult”—a sudden attack on the vulnerable inner layer of our arteries? They decided on a sausage-and-egg McMuffin meal; they weren’t messing around. Without the grapes, that meant cutting artery function nearly in half within an hour, and the artery stayed stiffened and crippled three hours later. But, eat that McMuffin with all those grapes, and hardly any effect.

Eat a meal with hamburger meat, and artery function drops after the meal. But, eat that same meal with some spices, including a teaspoon and a half of turmeric, and your artery function gets better.

What about orange juice? Four cups a day for four weeks, and no change in artery function. Ah, but that was commercial orange juice, from concentrate. What about freshly squeezed orange juice? Here’s the before and, here’s the after—still nothing. That’s one of the reasons berries are the healthiest fruits.

Want a beverage that can improve your artery function? Green tea. Two cups of green tea, and you get that same cocoa effect, nearly four points within just 30 minutes. And, that same crazy effect you get with green tea, you get with black tea. Twice as powerful an effect as the açai berries.

So, why focus on just that one plant? Well, the real reason, presumably, is that the author owns a patent on an açai-based dietary supplement.

Please consider volunteering to help out on the site.

• Zielinski AA, Ávila S, Ito V, Nogueira A, Wosiacki G, Haminiuk CW. The association between chromaticity, phenolics, carotenoids, and in vitro antioxidant activity of frozen fruit pulp in Brazil: an application of chemometrics. J Food Sci. 2014 Apr;79(4):C510-6.
• Schauss AG. The Effect of Acai (Euterpe spp.) Fruit Pulp on Brain Health and Performance.
• Pérez-Jiménez J, Neveu V, Vos F, Scalbert A. Identification of the 100 richest dietary sources of polyphenols: an application of the Phenol-Explorer database. Eur J Clin Nutr. 2010 Nov;64 Suppl 3:S112-20.
• Yamaguchi KK, Pereira LF, Lamarão CV, Lima ES, da Veiga-Junior VF. Amazon acai: chemistry and biological activities: a review. Food Chem. 2015 Jul 15;179:137-51.
• Rocha A, Carvalho LC, Sousa MA, Madeira SV, Sousa PJ, Tano T, Schini-Kerth VB, Resende AC, Soares de Moura R. Endothelium-dependent vasodilator effect of Euterpe oleracea Mart. (Açaí) extracts in mesenteric vascular bed of the rat. Vascul Pharmacol. 2007 Feb;46(2):97-104.
• Alqurashi RM, Galante LA, Rowland IR, Spencer JP, Commane DM. Consumption of a flavonoid-rich açai meal is associated with acute improvements in vascular function and a reduction in total oxidative status in healthy overweight men. Am J Clin Nutr. 2016 Nov;104(5):1227-1235.
• Inaba Y, Chen JA, Bergmann SR. Prediction of future cardiovascular outcomes by flow-mediated vasodilatation of brachial artery: a meta-analysis. Int J Cardiovasc Imaging. 2010 Aug;26(6):631-40.
• Rodriguez-Mateos A, Rendeiro C, Bergillos-Meca T, Tabatabaee S, George TW, Heiss C, Spencer JP. Intake and time dependence of blueberry flavonoid-induced improvements in vascular function: a randomized, controlled, double-blind, crossover intervention study with mechanistic insights into biological activity. Am J Clin Nutr. 2013 Nov;98(5):1179-91.
• Rodriguez-Mateos A, Del Pino-García R, George TW, Vidal-Diez A, Heiss C, Spencer JP. Impact of processing on the bioavailability and vascular effects of blueberry (poly)phenols. Mol Nutr Food Res. 2014 Oct;58(10):1952-61.
• Heiss C, Kleinbongard P, Dejam A, Perré S, Schroeter H, Sies H, Kelm M. Acute consumption of flavanol-rich cocoa and the reversal of endothelial dysfunction in smokers. J Am Coll Cardiol. 2005 Oct 4;46(7):1276-83.
• Nakayama H, Tsuge N, Sawada H, Masamura N, Yamada S, Satomi S, Higashi Y. A single consumption of curry improved postprandial endothelial function in healthy male subjects: a randomized, controlled crossover trial. Nutr J. 2014 Jun 28;13:67.
• Chaves AA, Joshi MS, Coyle CM, Brady JE, Dech SJ, Schanbacher BL, Baliga R, Basuray A, Bauer JA. Vasoprotective endothelial effects of a standardized grape product in humans. Vascul Pharmacol. 2009 Jan-Feb;50(1-2):20-6.
• Asgary S, Keshvari M, Afshani MR, Amiri M, Laher I, Javanmard SH. Effect of fresh orange juice intake on physiological characteristics in healthy volunteers. ISRN Nutr. 2014 Mar 4;2014:405867.
• Alexopoulos N, Vlachopoulos C, Aznaouridis K, Baou K, Vasiliadou C, Pietri P, Xaplanteris P, Stefanadi E, Stefanadis C. The acute effect of green tea consumption on endothelial function in healthy individuals. Eur J Cardiovasc Prev Rehabil. 2008 Jun;15(3):300-5.
• Jochmann N, Lorenz M, Krosigk Av, Martus P, Böhm V, Baumann G, Stangl K, Stangl V. The efficacy of black tea in ameliorating endothelial function is equivalent to that of green tea. Br J Nutr. 2008 Apr;99(4):863-8.

Icons created by Peter Parnican and Sagit Milshtein from The Noun Project.

Motion graphics by Avocado Video.