Scientists have been investigating resveratrol, a compound found in grapes, berries, peanuts, cacao beans, knotweed and many other plants for about four decades. They have discovered that this polyphenol has antioxidant, anticancer and anti-inflammatory activity (Biomedicines, Sep. 9, 2018). Plants apparently produce it as a protection against fungi and possibly other pathogens. Could resveratrol help human health?
Several years ago, scientists at the Scripps Research Institute in La Jolla, California, discovered that resveratrol partners with an enzyme that connects tyrosine to RNA (Nature, Dec. 22, 2014). This seems to be protective under stressful conditions. Together, resveratrol and the enzyme enter the nucleus and stimulate DNA repair.
Can Resveratrol Help Fight Stress?
In fact, a new study shows that this compound can help reduce stress (Neuropharmacology, July 15, 2019). The researchers studied the effects of resveratrol on the stress hormones cortisol and corticosterone in laboratory mice. When these hormones increase, they affect the hippocampus in the brain. The mice respond with behavior suggestive of anxiety or depression. Resveratrol inhibits a brain enzyme called phosphodiesterase-4D. By putting the brakes on PDE-4D, it protects the hippocampus from stress-related damage.
What Else Can Resveratrol Help With?
Scientists have been investigating the potential of resveratrol to prevent heart disease and other cardiovascular conditions. In addition, they are interested in its ability to ward off cancer and delay cognitive decline. So far, however, almost all of the research has been in test tubes or laboratory animals. When investigators give resveratrol to humans, they may get conflicting results.
Resveratrol Disappointment in Tuscany:
People frequently think of resveratrol as “the red wine compound.” Some researchers even suggested that resveratrol in red wine might help explain the “French paradox.”
Amazing wine grower territory and vineyard with house on the hill, Chianti region, Tuscany, Italy, Europe
On the other hand, a study conducted in Tuscany suggested that people who get more resveratrol by drinking red wine may not live longer. The researchers followed nearly 800 older Italians for nine years (JAMA Internal Medicine, July 2014). Urine specimens were collected at the beginning of the study along with dietary surveys. The investigators were able to estimate resveratrol intake from these.
During the decade of the study about one third of the participants died. Variations in urinary resveratrol levels were not associated with differences in mortality, heart disease or cancer rates. One significant difference, however, was in cognitive function. People with the highest levels of resveratrol were less likely to be impaired.
This was a relatively small epidemiological study and did not randomize people to receive resveratrol supplements compared to placebo. Instead, the participants dosed themselves by drinking the wine that is abundantly produced in the region. Those who drank more wine had higher levels of resveratrol in their urine.
Maintaining Cognitive Function:
Could resveratrol help people keep their brains working better as they age? Some clinicians think so (Archives of Medical Science, July 2019). So far, however, the trials have been small and more suggestive than definitive.
Preventing Certain Cancers:
A review of the research on cancer prevention with resveratrol suggests that it may be useful against a variety of tumors (Critical Reviews in Food Science and Nutrition, June 13, 2018). In particular, it may help reverse cancer cells’ resistance to common chemotherapy drugs (International Journal of Molecular Sciences, Dec. 1, 2017). If oncologists are able to figure out the appropriate dose and timing to elicit this response, resveratrol could be extremely useful.
Researchers in Fujian, China, have found that resveratrol can help prevent the progression of osteoporosis in rats (European Review for Medical and Pharmacological Sciences, July 2019). We will be interested to see if their research can be translated to benefit humans.
In conclusion, we can observe resveratrol help rodents, including anxious mice and estrogen-deprived rats. We don’t yet have clear indications that taking resveratrol as a supplement would be useful for human health. The research is tantalizing, though. Given the wide range of plant foods that can provide this compound, the best advice might be to continue to include grapes, red wine, peanuts, plums, cocoa, blueberries, bilberries and cranberries in your diet.