Modern science is catching up with ancient wisdom. The expression “Let food be thy medicine and medicine be thy food” has been attributed to Hippocrates, father of medicine, around 431 B.C. Hippocrates’ adage is aptly illustrated by a glance down a supermarket produce aisle with its colorful display of deep red strawberries, fiery orange carrots, bright green broccoli and brilliant blueberries. The vibrant hues found in plant pigments that create these distinct colors have aroused the interest of the scientific community as vast amounts of research uncovers the beneficial effects these “phytonutrients” have on preventing disease and maintaining health.
Antioxidants, phytonutrients, and polyphenols have become familiar buzzwords to the health-oriented, and certain fruits and vegetables have achieved “superfood” status due to their high content of these beneficial compounds. In the arena of produce with high antioxidant abilities, blueberries have topped the list. Blueberries are considered the gold standard due to their high levels of polyphenols, which are a subgroup of phytochemicals. Anthocyanins are a further subgroup of polyphenols and provide the pigments that color deep red and purple foods such as blueberries, acai, blackcurrant and red wine. Research has shown these polyphenols to protect against diabetes, cardiovascular disease, memory loss, inflammation and cancer.
As blueberry availability is limited by its growing season, there are times when it is difficult to obtain the fresh product or they are priced at a premium, and blueberries are high in sugar, requiring limited consumption for people on restrictive diets. Is it possible for another commonly available fruit or vegetable to rival the high polyphenol content of blueberries? Rutgers Distinguished Professor in Plant Biology Ilya Raskin has selected lettuce, one of the most widely consumed and affordable vegetables and readily available year round in the U.S. to boost its polyphenol content. Using red leaf lettuce, Raskin’s laboratory selected samples with the highest polyphenols. From there, using a non-transgenic process of tissue culture which replicates plant cells in a petri dish, then propagating in growth chambers and finally analyzing them for levels of polyphenols, anthocyanins and other antioxidants, Raskin developed a deep burgundy red lettuce that has elevated levels of polyphenols – two to three times that of blueberries.
The high polyphenol lettuce has been named Rutgers Scarlet Lettuce (RSL) – a tribute to Rutgers’ school mascot and color, the Rutgers Scarlet Knights. In addition to its high polyphenol profile, RSL has a low glycemic index, preventing spikes in blood sugar that foods high in carbohydrates or sugars, such as fruits and berries, can cause. This was demonstrated through a trial where diabetic mice given Rutgers Scarlet Lettuce showed significant decrease in blood glucose and insulin resistance compared to diabetic mice given regular lettuce. RSL is also high in chlorogenic acid, a polyphenolic compound found in high amounts in green coffee beans, known for its beneficial properties particularly for diabetes, metabolic syndrome and obesity.
In addition to the study on blood glucose levels that was published in the scientific journals PLOS ONE and also Nutrition, Raskin’s team has also conducted a 13-week feeding study where diet-induced obese mice fed a high fat diet supplemented with RSL demonstrated improved glucose metabolism when compared to mice fed green lettuce or a high fat diet without the RSL. RSL is also being tested using an artificial gut model system that Rutgers uses to determine bioavailability of food to investigate whether nutrients make it through the digestive process. The system, known as TIM- (TNO Intestinal Model) demonstrated that chlorogenic acid and quercetin glucosides from RSL are bioaccessible, and therefore are likely to be at least partially responsible for the beneficial health effects of RSL.
With its exceptionally high profile of phytonutrients in addition to the regular benefits of lettuce of vitamins, minerals, low calorie and high fiber, RSL is the first lettuce worthy of superfood status. “Lettuce is one of the most widely consumed vegetables after potatoes,” said Raskin. “This adds functionality to something that is not known for being good or bad.”
To introduce RSL to the market, Rutgers has patented and licensed RSL to Nutrasorb LLC, a Rutgers spin-off company that specializes in enhancing phytoactive compounds in foods. Nutrasorb has granted a license to Shamrock Seeds as the exclusive seed dealer for RSL. Shamrock specializes in vegetable seed for commercial growers in the major salad growing regions in the U.S. and anticipates interest from growers throughout the U.S. RSL seed is available to large and medium size farms — there is a minimum purchase requirement — which must sign an agreement to use the licensed product. Commercial growers can obtain the RSL seed for growing as loose leaf lettuce or baby greens. David Griffin, CEO for Shamrock said “We went to all the grower/shippers and produce companies in the area to announce this great development and talked to them about the opportunities that existed to be able to promote this new health benefit in lettuce. We’re very excited by it and we look forward to getting it out in the marketplace.”
The produce companies that Shamrock is working with will be supplying it as whole head lettuce, bagged salad and bowls and through food service. The companies are not required by the agreement to use the Rutgers Scarlet Lettuce name, however the cohesive factor that will help consumers identify the product is Nutrasorb’s “Food4Good” trademark will be on the product label.
The first company to launch this product will be Coastline Family Farms, a major produce shipping company based in Salinas, CA. Coastline has selected and trademarked the name Nutraleaf™ for the brand and will be the exclusive grower/shipper of whole head and artisan-pack Nutraleaf™ Burgundy Leaf Lettuce and Nutraleaf™ Burgundy Romaine for distribution throughout North and South America. Their agreement with Shamrock allows for exclusive distribution of whole head lettuce for one year. Coastline Family Farms President, Steve Henderson recognized the opportunity to enhance their mission of providing health promoting foods. “We learned of the new high-antioxidant lettuce and Romaine, created by Rutgers, The State University of New Jersey, and decided we wanted to be a part of this trend in growing and marketing nutritionally superior products.” Coastline’s product launch was October 18 with official introductions taking place on both coasts. The Produce Marketing Association, a trade organization representing companies from the global fresh produce supply chain, held their Fresh Summit Convention & Expo in Anaheim, CA while the Academy of Nutrition and Dietetics held their Food & Nutrition Conference & Expo in Atlanta, GA. Communications to professionals in these fields on the Nutraleaf™ lettuces was initiated at these events. Coastline is also developing a nutrition-based campaign to consumers, and their rollout will continue with a test markets in several major metropolitan areas. More information on Nutraleaf™ lettuces is available at: www.coastlinefamilyfarms.com/nutraleaf.
Despite it being packed with nutrients, consumers will want to know – does the lettuce taste good? Registered dietician Sharon Palmer, author of The Plant-Powered Diet, sampled Coastline’s Nutraleaf™ product. Palmer comments in a post on NutraLeaf™ in her blog, “It’s not only packed in antioxidants, vitamins and minerals, but this lettuce is tender and delicious, too. In fact, lettuce is one of America’s favorite vegetables, so I love the idea of getting more nutrients into your daily salad.” Palmer adds, “And maybe the best thing about NutraLeaf is just how beautiful it looks in salads, serving as a deep purple color contrast for a number of your favorite salad ingredients.”
The development of Rutgers Scarlet Lettuce has been partially funded by a grant from National Institutes of Health and with additional financial and student research support from Rutgers New Jersey Agricultural Experiment Station. Raskin’s lab is planning further research for increasing polyphenol and other nutrients content in lettuces.