Black Raspberries Show Sweet Potential for Oral Cancer Prevention

Black Raspberries and Oral Cancer  OSUCCC  James

Cancer researchers at The Ohio State University are optimistic about an ongoing study that examines the efficacy of black raspberries in preventing oral cancer in smokers.

The study is conducted through the university’s colleges of Dentistry, Medicine, Public Health, and Food, Agricultural and Environmental Sciences.

Purnima Kumar, DDS, PhD, a professor in the College of Dentistry, has been studying the effects of smoking on oral health for a good portion of her career.

“The easiest thing is to tell someone to quit smoking, but we know that it’s very difficult to quit,” says Kumar, principal investigator for the black raspberry study. “So the alternative is to figure out a way to mitigate the harmful effects of smoking.”

Previously reported research at Ohio State shows that phytochemicals in black raspberries can protect smokers from oral disease and lower their risk for developing oral cancer. This particular study, which began in May 2017, is looking at how concentrated black raspberry components affect bacteria in the mouths of smokers.

“Your body is a series of ecosystems with lots of bacteria working in harmony,” Kumar says. “We know that smoking alters these bacterial communities and how the immune system perceives them.”

There are good bacteria and bad bacteria, she explains. The antioxidants in black raspberries inhibit the growth of pathogen (bad) bacteria.

“The mouth is very important. It’s the first point of entry to your entire body. This study uses one of the least invasive methods of testing,” Kumar says.

Ohio State incorporates a “Crops to Clinic” approach in many of its studies. In this instance, the College of Food, Agricultural and Environmental Sciences is turning black raspberries into a consumable (think tasty) drink, says Elizabeth Grainger, PhD, RDN, a clinical research nutritionist for The Ohio State University Comprehensive Cancer Center – Arthur G. James Cancer Hospital and Richard J. Solove Research Institute (OSUCCC – James).

“We know dietary patterns are important when it comes to disease prevention, and that consuming five to nine servings of fruits and vegetables a day is part of a recommended diet,” Grainger says. “Eating fresh black raspberries is a great idea, but there are many challenges with fresh berries in our large clinical trial, namely availability, volume, retention and appeal.”

Black raspberries are in season only a couple of weeks during summer, so availability and consistency become issues, Grainger says.

A person would need to consume one cup of black raspberries daily to obtain the equal concentration used in the study. To overcome this challenge, the fruit is freeze-dried and ground into a powder that can be used to make a safe food product that has a very consistent profile of nutrients.

The concentrate needs to stay in the mouth for maximum absorption. It takes only about six to eight seconds to chew and swallow, Kumar says. The black raspberry nectar used in the study contains a lot of pectin, which coats the inside of the mouth.

Smokers needed for clinical trial
Both smokers and non-smokers are participating in the current oral cancer prevention study. Participants are asked to drink the black raspberry concentrate, which is relative in size to a child’s juice box, once a day. For purposes of the study, some participants receive a placebo.

Two to three weeks after a person stops smoking, regenerative processes start to take place in the body, and it takes about three months for those changes to be completely stable, Kumar says. The study is following a similar timeline to see what effect the black raspberries have on oral health.

“Every day I see patients who smoke and ask them, ‘How can I help you?’” Kumar says. “Instead of performing surgery on someone who has oral disease, this study helps me find ways to prevent the disease.”

The OSUCCC – James is looking for more smokers to join the study, Grainger says.

What have the researchers learned so far? Kumar describes the findings as “futuristic science” that will be ongoing with unlimited potential for learning. “There are billions of data points, and our bioinformaticists are finding patterns in genes—both human and bacterial. We are continually sifting through the data.”

One observation researchers at the OSUCCC – James have made is that participants are reporting their gums don’t bleed (gingivitis) as much after drinking the concentrate.

Adds Grainger, “We are trying to home in on the complex mechanisms whereby black raspberries may be beneficial, but the message is simple: Black raspberries should be part of a plant-rich dietary pattern to reduce the risk of diseases.”

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