Tomatoes are the major disocvered source of lycopene, a potent anticarcinogen (particularly against pancretic cancer).
            Lycopene is the carotene that gives tomatoes and watermelon their red color, and may have developed as a way for plants to protect themselves from sunlight. Lycopene is not destroyed by heat, therefore it is present in every tomato product.
      Tomatoes also contain folic acid, vitamin C, potassium, beta-carotene, gamma-carotene, phytoene and flavonoids which may act in concert with lycopene.

      Dr. Frank Meyskens, a cancer researcher at the U. of California/Irvine, says new studies indicate that people with more lycopene in their blood are at lower risk of certain cancers, mainly of the cervix and pancreas.
      Researchers from Johns Hopkins have reported that people with the lowest blood levels of lycopene are five times more vunerable to pancreatic cancer.
      U. of Ilinois researchers have reported that women with the highest levels of lycopene had a five-fold lower risk of developing precancerous signs of cervical cancer than those with the lowest levels.

      Lycopene appears to reduce the risk of cancer by about 40 percent (in particular, prostate, lung and stomach cancers).
      Women with low lycopene levels are even more prone to a precancerous condition called cervical intraepithlal neoplasia, which can lead to cervical cancer.

      A 1997 Harvard study found that men who ate 10 servings of tomato-based foods/week were half as likely to develop prostate cancer as men who ate four servings. Lycopene was credited.
      [The most significant effect was shown by tomato sauce; tomato juice did not show as protective. Out of 42 other fruits and vegetables, only strawberries were also associated with a lower risk of protate cancer.]

      Karmanos Cancer Institute researchers gave men with prostate cancer 15 milligrams of lycopene 2x/day (equiv. = 1 1/2 cups of tomato sauce).
      Afer three weeks, 17 men had slightly smaller tumors. Lead researcher Dr. Omer Kucuk believes lycopene stops prostate cancer cells from multiplying.
      "The results are significant. It's remarkable that lycopene may have both therapeutic and preventive value."
      --- Dr. Frank Ruscher, Wistar Institute, Philadelphia
[Prostate cancer is the most common malignancy among American men.]

      "As intake of lycopene increases, the risk of malignancy of the prostate gland decreases. We are talking about a 30 to 40 percent reduction with 10 or more servings of tomato (products per week."
      --- Dr. Graham Colditz, epidemiologist, Harvard Medical School

      Men's Health magazine reported in the 5/99 issue that a Swiss study showed that a combination of lycopene and vitamin E inhibited prostate cancer cell growth by nearly 98 percent.

      Research from the 1999 Annual Meeting of the American Association for Cancer Research, Harvard Medical School (1995), American Journal of Epdemilogy (1997) and the Archives of Opthalmology (1995):

      * after taking 15mg of lycopene 2x/day for three weeks, men previously diagnosed with localized prostate cancer had smaller tumors and lower serum PSA levels
      * men who ate more than 10 servings of tomato products/week had a 33 percent lower risk of developing prostate cancer than men who ate fewer than 1 1/2 servings
      * people with more lycopene in their bodies had a much lower risk of heart attack than people with lower lycopene levels
      * those with low serum levels of lycopene were twice as likely to have age-related macular degeneration as people with higher levels.

      U. of Kentucky researchers found that elderly men who had the highest blood levels of lycopene were more physically and mentally active.

      The Journal of the National Cancer Institute, Feb. 17, 1999, reviewed 72 tomato studies and found 57 that linked frequent tomato consumption with reduced cancer risk, most strongly for cancers of the prostate, lung and stomach. Lower risk for reast, colon, cervical, pancreatic, oral and esophageal cancers was also suggested.
[author: Dr. Edward Giovannucci, Harvard School of Public Health]

MSNBC article

      Lycopene is twice as powerful as beta-carotene at stopping carcinogenic activity.
[Beta-carotene enhances the absorption of lycopene.]

      Watermelon contains 4.1mg of lycopene per 3.5 oz.; tomatoes 3.1mg/3.5oz..
      Best source estimates (amounts in milligrams per 100 grams):

    ketchup - 9.9 



   tomato juice - 8.6 



    tomato paste - 8.5 



    tomato sauce - 6.2 



    guava - 5.4 



    watermelon - 4.1 



   tomatoes, 

    cooked - 3.7 



   papaya - 3.7 



    grapefruit, 

    pink - 3.4 



   guava juice - 3.3 



    tomatoes, 

    raw - 2.9 



    apricots, dried - 0.9 

      Lycopene amounts in foods --- USDA Carotenoid Data Base, Campbell Soup Company "Lycopene: Chemical and Biological Properties", Food Technology (Feb 1999):

    tomato juice, 8oz. - 22mg.

   1/4 cup pizza sauce - 21mg.

   canned spaghetti sauce,

   pasta sauce, tomato
   sauce, 1/2 cup - 20mg.

   Campbell's tomato soup,
   1 cup - 12mg.

   canned diced tomatoes,
   1/2 cup - 12mg.

   tomato salsa, 1/2 cup - 12mg.

   canned tomato paste,
   2 tablespoons - 10mg.

   watermelon, 1 cup - 8mg.

   guava, 1 medium - 5mg.
   ketchup, 2 tbls. - 5mg.

   fresh tomato,
   chopped, 1/2 cup - 3mg.

   pink or red
   grapefruit, 1/2 cup - 2mg.

   fresh tomato,
   2 medium slices - 1mg.

[ The mixed juice of carrots, celery and tomatoes drew particular interest from the NCI's Designer Foods Program. ]

[ Tomato puree is a particularly rich source of lycopene, and can be found in many canned foods.

      German studies reveal that lycopene is best absorbed by the body from cooked tomatoes. Cooking breaks down cell walls, increasing the amount of lycopene available to the body for use.
      Canned tomatoes, tomato sauces (ketchup, spaghetti/pasta, etc.) and chili sauces are extremely rich in lycopene. Concentrated sauces have five times more lycoene than fresh tomatoes.
      Products that contain "tomato extract" or "tomato concentrate" are made from whole tomatoes and should contain all the phytochemicals normally found in tomatoes.

      Dr. John W. Erdman, U. of Illinois in Chicago:
  "Lycopene is a fat-soluble substance, and for it to be absorbed through the intestines, it must be consumed with fat. About 20 percent calories fat calories in a meal (maybe a little less) should be sufficient.
      Drinking tomato juice by itself results in no meaningful absorption of lycopene. The lycopene and beta-carotene in the juice are so insoluble in water that they will go right throgh the digestive tract and out the other end."

[Pale tomatoes have less lycopene than deep red ones. Tomatoes ripened on the vine are likely to have more lycopene than those that ripen after they are picked.]

      Foods that can inhibit lycopene absorption:

      * soluble fibers (pectin, gums, etc.)
      * cholesterol-binding resins used to lower serum cholesterol (cholestyramine, etc.)
      * the fat substitute, olestra (which may result in NO lycopene absorption)