Nutrient Interaction for Cancer

This brings us to another important topic: nutrient interaction. Medical science has, for far too long, treated nutrients as just more objects to explore. In their way of thinking, which is very archaic, if you want to know why something works-for example, why fruits and vegetables can reduce the risk of cancer you simply extract the components found in the highest concentrations and test them. Citrus fruits have a lot of vitamin C, so to the popular way of thinking, you just give test animals and people lots of vitamin C and see if it works. Sometimes it does, sometimes it has no effect, and on rare occasions, it actually increases the growth of cancer.

The problem with this way of thinking is that nutrients do not normally work alone, especially in as complex a biological system as exists in people. To a large part, this is because of the interactions of the biochemical systems, where altering one part of the system may affect a dozen or more other parts of the sys tern. Another important consideration is that the nutrients them selves interact. This is especially true when dealing with anticancer effects.

One of the more powerful interactions between nutrients and anticancer effects is seen with vitamin E and selenium. Several animal studies as well as studies of large populations of women have shown that vitamin E reduces the risk of breast cancer, especially in women at very high risk of the disease. But when you add selenium to the vitamin E, an even greater lowering of the risk is seen.

If we look at whole fruits and vegetables, we notice that vitamins never occur alone. This is very important, since vitamins keep each other from oxidizing. Vitamin C protects vitamin E, beta-carotene protects vitamin C, and so on. Recent studies emphasize the importance of mixing these nutrients in our diet and as supplements.

To emphasize the importance of nutrient interaction, let us look at the Physicians' Health Study, which involved 22,071 doctors, making it one of the largest nutritional studies ever done. The researchers isolated 578 men with prostate cancer in the study group and compared their diets to those of 1,294 con trols. They found that the men with the highest blood levels of lycopene, the red pigment in tomatoes, had a dramatically lower incidence of prostate cancer, especially of the very aggressive type; some had as much as a 60 percent lower incidence. Yet, beta-carotene had no effect on the risk of the disease-at least, not in the men with normal levels of lycopene. To the re searchers' surprise, beta-carotene did have a major effect on re ducing the prostate cancer risk if a man's lycopene level was low. This, once again, emphasizes the interrelationship between nutrients and anticancer effects,

Special Cancer Killers in Plants

While most people think of vitamins as antioxidants and as the major nutritional weapons against cancer, other plant chemicals are, in fact, infinitely more powerful. Of major interest to cancer researchers are the flavonoids, a group of 5,000 very complex chemicals. Like vitamins, they also work best when together. A single vegetable or fruit can contain hundreds of these chemi cals. In addition, their anticancer activity is further enhanced by the presence of vitamins.

There is growing evidence that the effectiveness of nutrients when combined is not only additive, but synergistic. An additive effect is two plus two equals four, whereas a synergistic effect is two plus two equals twelve or twenty. Not only do certain nutrients enhance each other's anti cancer activity, they also dramatically enhance the ability of anti cancer drugs and radiation to kill cancer cells, as we shall see later.

Not All Foods Are Created the Same

One factor that is rarely considered is the nutritional variation among foods. For example, we often hear that apples are a good food for preventing cancer. Yet, all apples are not the same in terms of cancer-preventing abilities. One of the known anti cancer constituents in apples is a chemical called chlorogenic acid, yet the content of chlorogenic acid varies considerably among the different species of apples, with the McIntosh containing a very high level and the Golden Delicious a very low level.

Whether a fruit or vegetable is vine ripened also makes a dif ference. Many fruits and vegetables found in our local market were shipped across the country. To keep produce from spoiling during shipping, the produce companies pick the plants before they ripen, which means that these fruits and vegetables have lower concentrations of nutrients. Sometimes young sprouts have a greater concentration of a particular beneficial nutrient than the fully matured vegetable. For example, broccoli sprouts have been shown to have as much as 100 times more indole-3 carbinol, a powerful inhibitor of breast cancer, than mature br.occoli.9 Several nutritional companies have taken advantage of this observation by offering numerous types of plant sprouts, such as wheat, rye, and barley.

Not all vegetables and fruits have the same cancer-fighting power. The produce with the greatest anticancer effect are the cruciferous vegetables, which include kale, broccoli, Brussels sprouts, cauliflower, and cabbage.

This is not to say that other vegetables are of no help because beets, parsley, spinach, carrots, and tomatoes have all been shown to have equally powerful anticancer effects. In general, fruits and vegetables with deep colors have the greatest anti cancer effectiveness.

Most people are aware that our soil-the sole source of nutrients for plants-is terribly depleted of nutrients. For example, the soil in many areas of the United States is severely depleted of the mineral selenium. People eating vegetables grown in selenium depleted soil can develop severe selenium deficiencies, thereby greatly increasing their risk for certain cancers, including breast and prostate cancers. Selenium plays a major role in immune system function as well, especially in the immune cells that attack cancer.