Also known as arctic root or golden root, Rhodiola Rosea has already been clinically shown to stimulate serotonin, norepinephrine and dopamine activity, and support healthy neurotransmitter balance, but human trials have now shown the the herb protects against viral infection.
Ground breaking studies led by David Nieman, DrPh, FACSM, director of the Appalachian State University Human Performance Laboratory at the NC Research Campus (NCRC) in Kannapolis, are
building on previous human trials that demonstrate the anti-viral activity of blueberry and green tea polyphenols.
A 2002 review in HerbalGram
, the journal of the American Botanical Council, reported that numerous studies of rhodiola in both humans and animals have indicated that it helps prevent fatigue, stress, and the damaging effects of oxygen deprivation. Evidence also suggests that it acts as an antioxidant, enhances immune system function, and can increase sexual energy. Rhodiola's efficacy was confirmed in a 2011 review of 11 placebo-controlled human studies. The reviewers considered studies that all had study designs rated as moderate to good quality, and the analysis of their combined data concluded that rhodiola might have beneficial effects on physical performance, mental performance, and certain mental health conditions.
Testing For Anti-Viral Defense
Nieman’s study "Rhodiola rosea exerts antiviral activity in athletes following a competitive marathon race," which was published July 31 in Frontiers in Nutrition, is the first to show anti-viral activity.
In his study, 48 marathon runners participating in the 2012 Thunder Road Marathon in Charlotte were randomly divided into two groups that ingested either 600 milligrams of Rhodiola rosea or a placebo for a month before the race. Blood samples were collected the day before the marathon and 15 minutes and 1.5 hours post-race. Initial studies found no impact on inflammation and oxidative stress. Additional studies used an in vitro assay to measure the ability of the polyphenolic compounds to protect the cells against Vesicular stomatitis virus. The results demonstrated that Rhodiola rosea delayed viral infection for up to 12 hours after the marathon.
Nieman was the first scientist to find that marathon runners are prone to viral illnesses such as upper respiratory tract infections after competing. This discovery motivated him to research plant-based compounds that could prevent infection and enhance recovery and overall athletic performance.
Since Rhodiola rosea administration appears to impact central monoamine levels, it might also provide benefits and be the adaptogen of choice in clinical conditions characterised by an imbalance of central nervous system monoamines. It also suggests that research in areas such as seasonal affective disorder, fibromyalgia, and chronic fatigue syndrome, among others, is warranted.
"Basically after heavy exertion, bacteria and viruses can multiply at a higher rate than normal due to factors in the serum like stress hormones and inflammatory cytokines," Nieman said. "This is why runners are six times more likely to get sick after a marathon. We showed that in those who used Rhodiola rosea the viruses could not multiply, meaning it was acting as a countermeasure."
The in vitro assay used in the study was developed by Nieman and Maryam Ahmed, PhD, an associate professor of biology at Appalachian who is a virology expert and study co-author.
"A lot of these types of compounds, you cannot test in humans," Ahmed said. "So the really unique aspect of this study is that we gave these individuals the supplements, and we were able to test their blood in the lab using the experimental procedures that we developed to find out whether the compounds in the blood can protect cells against viruses."
Using the specially developed assays, Ahmed and Nieman also identified a mix of polyphenolic compounds from green tea and blueberries that is even more effective than Rhodiola rosea at preventing viral replication in athletes after intense competition. Those findings were reported in the 2014 study "The Protective Effects of a Polyphenol-Enriched Protein Powder on Exercise-Induced Susceptibility to Virus Infection" that was published in the journal Phytotherapy Research. The study was led by Nieman in collaboration with the Dole Nutrition Institute and the NC State University Plants for Human Health Institute, both at the NCRC.
Anybody Can Benefit
Rhodiola both stimulates and protects the immune system by reinstating homeostasis (metabolic balance) in the body. It also increases the natural killer cells (NK) in the stomach and spleen. This action may be due to its ability to normalise hormones by modulating the release of glucocorticoid into the body.
Both Nieman and Ahmed assert that the anti-viral effects of polyphenols are beneficial to more than athletes. In a 2012 study published in the journal Nutrients, Nieman lead a 1,000 person community study that demonstrated people who eat three or more servings of fruit per day substantially reduced their incidence of upper respiratory tract infections.
"These compounds that we are looking at are not only for athletes," Ahmed said. "They are also anti-oxidant and anti-cancer and have other properties that can benefit the general public."
Nieman added, "We are producing some of the first human studies showing plant polyphenols -- the naturally occurring chemicals in fruits and vegetables that give them their colors like purple, red and yellow -- work with the immune system to help clear viruses and keep their ability to multiply under control."