For athletes, polyphehols from foods like blueberries and green tea may be the best defense against the common cold and other viral infections.
Viral Defense Shield
Polyphenols are bioactive compounds in fruits and vegetables that research links to health benefits like anti-aging, anti-inflammation and anti-viral effects. A recent study conducted by NC Research Campus (NCRC) scientists provided novel evidence that athletes who are prone to viral illnesses should increase dietary intake of polyphenols to protect themselves against viruses.
Researchers from the Appalachian State University (ASU) Human Performance Laboratory and the NC State Plants for Human Health Institute (PHHI) with funding from the Dole Nutrition Institute (DNI) had athletes consume a protein powder combined with the polyphenols from blueberries and green tea for 17 days. The athletes exercised intensely for the final three days. The athletes ingested an amount of polyphenols equivalent to consuming three cups of blueberries and a cup-and-a-half of green tea per day.
After testing the athletes’ blood serum, viral replication was dramatically reduced compared to the placebo group. The placebo group received a powder without polyphenols and experienced higher than normal virus replication after the three days of intense exercise. The findings were published in the paper “The Protective Effects of a Polyphenol-Enriched Protein Powder on Exercise-Induced Susceptibility to Virus Infection” in the journal Phytotherapy Research (August 2014, e-publication).
“This is the first study of its kind to show that athletes who regularly eat polyphenols had more anti-viral protection after three days of intensive running. This has never been shown before,” said lead author David Nieman, DrPH, director of the ASU lab. “I highly recommend that athletes increase their polyphenol intake from fruits and vegetables to reduce their likelihood of getting sick from viral illnesses.”
More Bang for Your Blueberry
To make the polyphenol-protein powder, sugar and any pectins or water from fruits and vegetables are removed leaving the phytoactive compounds. Study co-author Mary Ann Lila, PhD, PHHI director, is a co-inventor of the powder used in the study, which is commercially known as Nutrasorb.
“We know that eating whole fruits and vegetables isn’t necessarily the same as eating the phytoactive components,” Lila said. “We are supposed to eat five cups of fruits and vegetables per day. On average people eat 1.8 cups. So with the Nutrasorb powder we are making it easier and more convenient to get the health benefits, like anti-viral effects, when fresh fruits are not feasible.”
In August 2013 in PLoS One, ASU, NCSU and Dole published the first paper using the Nutrasorb powder with athletes. The study showed most of the polyphenols in the powder ended up in the colon. The intense exercise created what Nieman calls a “leaky gut” that he believes is beneficial for athletes, allowing more of the polyphenolic compounds to move from the colon back into the blood.
“In other words, more bang for each blueberry or cup of green tea,” he commented.
Both of the studies reflect Dole’s long-term commitment to health and wellness research and education. “In the short term,” said Nicholas Gillitt, PhD, vice president of nutrition research for Dole and DNI director, “we can learn about what impacts inflammation and oxidative stress in athletes and helps them perform or recover better. In the long term, these types of findings give us clues as to what happens during disease progression, which in many cases involves inflammation and oxidative stress.”
Future research will explore the physiological mechanism that is associated with the anti-viral effects of the polyphenol-protein powder.