Scientific symposium also eyes link between lycopene and other tomato carotenoids and vision health
NEW YORK, Apr. 11, 2001 – Tomato-based foods and tomatoes may reduce risk of damage to the lungs caused by ozone, according to new preliminary findings from research presented today at an international scientific symposium on “The Role of Tomatoes and Tomato Products in Disease Prevention.” This study and others presented at a symposium, sponsored by the American Health Foundation, point to a variety of new potential benefits from consumption of tomato-based foods including possible protection against age-related macular degeneration, cataracts and other diseases of the eye.
“The latest findings on the benefits of tomato carotenoids, including lycopene, suggest that they may play a role in lung and vision function in healthy people,” says Daniel Nixon, MD, president of the American Health Foundation, and director of the Foundation’s Cancer Center. “Other studies presented further add to our understanding of the benefits that tomato-based foods may have for protection against cancers in specific organs, such as the prostate and lungs, and more recently to a decreased risk of cardiovascular disease.”
The health benefits of tomato products and lycopene, a carotenoid in tomatoes and the pigment that gives tomatoes their red color, first came to light in 1995 when a Harvard study showed that a reduced risk of prostate cancer was apparent in men who consumed a diet rich in tomato products.
New Research Findings
Reduced Risk of Ozone-Related Lung Damage
A pilot study conducted at the Environmental Protection Agency in Chapel Hill, NC, by Drs. Lenore Arab and Michael Madden, University of North Carolina at Chapel Hill, James Samet and colleagues at the US Environmental Protection Agency, Susan Steck-Scott, National Cancer Institute, showed a 12 percent increase in lung lycopene levels and a 20 percent decrease in oxidative damage to DNA in lung cells within two weeks time among individuals who consumed 12-ounce servings of vegetable juice cocktail in addition to supplement vitamins C and E. The results are based on 23 healthy adults who were exposed to ozone for two hours following two weeks of antioxidant intake, which included one can of V-8 vegetable juice daily or a placebo. Oxidative stress to the lungs is associated with high levels of ozone in the atmosphere, one of the damaging impacts of air pollution.
“This evidence indicates that lycopene and other carotenoids found in processed tomato products may protect the lungs against oxidative damage. This might impact the functionality of the lung. A number of observational epidemiologic studies have also shown potential protective effects of these types of diets on lung cancer risk,” states Dr. Arab.
Protection against Eye Disorders
Frederick Khachik, Ph.D., University of Maryland, College Park presented new information that, while preliminary, suggests that carotenoids, particularly lycopene, may protect the eye against oxidative damage and thereby plays a critical role in visual function. Dr. Khachik’s research review builds on the well established knowledge that lutein and zeaxanthin are the two main dietary carotenoids in ocular tissues and may provide protection against age-related macular degeneration (AMD), the leading cause of blindness in those 65 and older.
The identification of lycopene and a diverse range of dietary carotenoids in ocular tissues by Dr. Khachik suggests that these carotenoids as well as other nutrients found in tomato-based foods may work in concert with lutein and zeaxanthin to provide protection against AMD and other visual disorders. Lycopene is found in high concentrations in ocular tissues, with the exception of neural retina and the lens.
Also during the symposium, scientists discussed research showing that the cooking and processing of tomato products makes lycopene more readily available to the body, indicating that there may be an added health benefit to eating processed tomato foods like tomato soup, pasta sauce and vegetable juices. Steven K. Clinton, M.D., Ph.D., The Ohio State University, found that standard daily servings of tomato sauce, tomato soup, and V8 vegetable juice were each effective interventions to significantly increase blood concentrations of lycopene. Lycopene levels increased among study participants by 192% (pasta sauce), 122% (soup), and 92% (vegetable juice) respectively, and plateaued at a new baseline after only 14 days of consumption.
In addition, a review of two studies in Finland indicates that when diets are lacking in tomato products, the resulting low levels of blood lycopene significantly increases the risk for heart attack and stroke and early atherosclerosis among middle aged men. These studies support the contention that increased lycopene intake in men may play a protective role in cardiovascular disease, especially in early stages of atherogenesis.
“Lycopene co-exists with other carotenoids in tomato products, and the naturally occurring mixture may be superior in preventive effects to purified chemical lycopene,” explains David Heber, MD, Ph.D., Director of the UCLA Center for Human Nutrition. “Based on the research, I would recommend that men and women interested in reducing their risk of cancer eat at least five (5) servings of tomato-based foods per week. As little as eight ounces of tomato-based vegetable juice, an eight-ounce serving of tomato soup or a half-cup of tomato sauce have been shown to help elevate blood levels of lycopene in only two weeks.”
The International Symposium, sponsored by the American Health Foundation with an educational grant from the Campbell Soup Company, was held to discuss emerging research on the role tomato products play in human health, including heart disease and cancer prevention. Thirteen noted physicians and researchers from around the world presented their latest findings during the session. The American Health Foundation is the nation’s foremost preventive medicine research facility and a pioneer in research directed toward understanding the critical role of nutrition in preventing cancer development.