"The doctor of the future will give no medicine, but will interest his patients in the care of the human frame, in diet and in the cause and prevention of disease."
- Thomas Edison
improves lycopene absorption from other foods.
Ralph W. Moss, Ph.D. Weekly CancerDecisions.com
Newsletter #68 01/09/03
Wow, You Coulda Had Some Lycopene!
In a recent study from North Carolina, drinking just one can (5.5 ounces) per day of the popular vegetable drink, V-8, raised levels of lycopene in the lungs by 12 percent. It also decreased ozone-induced DNA damage to the lungs by 20 percent.
Like beta-carotene, lycopene is a member of the carotenoid family, a group of colorful plant compounds that are potent antioxidants. But lycopene is more than just a lung protectant. Evidence continues to accumulate that this phytonutrient has powerful anticancer properties.
Studies have shown that people who eat lots of tomatoes and tomato products have less prostate cancer. For instance, in 1995, the Physicians' Health Study found a one-third reduction in prostate cancer risk in the group of men with the highest consumption of tomato products compared to the group with the lowest consumption. The authors attributed this protective effect to the lycopene content of tomatoes.
A recent clinical trial from Detroit suggests that lycopene is also powerful medicine for men who already have prostate cancer. This trial, from the Karmanos Cancer Institute at Wayne State University, looked at the impact of short-term lycopene supplements on men who were facing surgery for newly diagnosed prostate cancer. The 26 patients in this study were randomly assigned to receive either a tomato extract (containing 30 milligrams of lycopene) or no supplement for 3 weeks before undergoing radical prostatectomy.
Men who received the lycopene supplement had lower prostate-specific antigen (PSA) levels and less aggressive tumors than the non-supplemented control group. Their tumors were smaller (80 percent of the tumors were under 4 milliliters (ml) in volume, compared to 45 percent in the control group). Their cancer was much more likely to be within the surgical margins and/or confined to the prostate gland (73 percent, compared to 18 percent of the control group). And the invasion of the prostate gland by cancer-like "PIN" cells was completely prevented in this group, compared to a 33 percent incidence of "PIN" cells in the control group.
"This pilot study suggests that lycopene may have beneficial effects in prostate cancer," concluded researcher Omer Kucuk, MD, and colleagues. They called for larger clinical trials "to investigate the potential preventive and/or therapeutic role of lycopene in prostate cancer."
Lycopene may also help prevent liver cancer, according to findings from a study presented at the American Association for Cancer Research meeting in October 2002. Hoyoku Nishino, MD, of the Kyoto Prefectural University of Medicine, Japan, presented the results of this five-year clinical study examining the protective role of lycopene and other nutrients in people at high risk of liver cancer. There was a 50 percent decrease in hepatocellular carcinoma (HCC or liver cancer) in participants who daily consumed 10 milligrams of tomato lycopene plus other tomato phytonutrients, 10 milligrams of carotenes (30 percent alpha, 60 percent beta-carotene), and 50 milligrams of alpha-tocopherols and another form of vitamin E, tocotrienols. These results suggest that a mixture of natural tomato extract, carotenes and vitamin E has clinical promise.
Skeptics at the National Cancer Institute (NCI) say that "the evidence is weak that lycopene is associated with a reduced risk [of prostate cancer] because previous studies were not controlled for total vegetable intake (i.e., separating the effect of tomatoes from vegetables in general)." They therefore state that "specific dietary supplementation with lycopene remains to be demonstrated to reduce prostate cancer risk." This statement appears on the NCI's Prostate Cancer Prevention web page, which was updated in September 2002. However, it does not reference the Detroit study or any scientific article presented or published after January 2000.
Few scientists doubt that a high intake of fruits and vegetables can decrease the rate of prostate and other forms of cancer, and it is surprising, but not implausible, that stepping up vegetable consumption could downgrade malignancies, even in just one month. The results reported from the Karmanos Center and elsewhere are very exciting. Any patient facing cancer would certainly want to see these dramatic effects on his or her malignancy. The main scientific question seems to be whether these changes are caused by lycopene itself or by some other nutrients in vegetables.
But why wait till researchers unravel these scientific mysteries? Given their many benefits, I suggest that you step up your intake of tomato products and other antioxidant-rich foods. As the North Carolina study demonstrates, just one small can of V-8 juice per day will raise lycopene levels in the lungs by 12 percent. In a two-week study at Ohio State University, blood lycopene levels were raised 192 percent by a daily serving of tomato sauce, 122 percent by tomato soup, and 92 percent by V-8 juice.
If you eat some tomato products every day and then supplement that with natural carotenes and vitamin E you will get the desired effects. While V-8 is rich in lycopene (it represents 88 percent of all the carotenoids in this juice), I would favor an organic version of the same mixture from the natural foods market. Also, keep in mind that there is more lycopene in cooked tomato products than in fresh tomatoes, and the absorption of lycopene by the body is enhanced by the presence of fat or oil. (This is probably the health rationale for the Italian custom of dribbling olive oil over fresh tomatoes.)
Lycopene supplements (such as Lyc-O-Mato) are another option. However, with tomato products so readily available, it seems unnecessary to add another pill to your daily regimen. As I wrote in Antioxidants Against Cancer (2000), the best source of antioxidants remains the high-quality organic foods that you consume in your daily diet.
--Ralph W. Moss, PhD
Arab L et al. Lycopene and the lung. Exp Biol Med
Giovannucci E et al. Intake of carotenoids and retinol
in relation to risk of prostate cancer. J Natl Cancer
Kucuk O et al. Effects of lycopene supplementation in
patients with localized prostate cancer. Exp Biol Med
Food Ingredients First. Lycopene may help prevent
liver cancer. October 12, 2002.
National Cancer Institute. Prostate cancer prevention:
PDQ. Prevention with lycopene.
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