The Cancer Chronicles Read Online Free PDF Page A

taken root, extra doses might even accelerate its growth, adding fuel to the fire. Some cancers are combated byadministeringantifolates, which areamong the oldestchemotherapeutic drugs. The most persuasive reason for eating spinach is that, sautéed with garlic or tossed in a salad, it tastes so good.
    Just as dubious isthe mythology surroundingantioxidants like vitamins C and E, which are consumed in fruits, vegetables, and pills and smeared on the face in the form of antiaging cosmetics. The hope is to counteractfree radicals—products of cellular combustion that eat at the insides of cells. It is far from clear that the body needs help on that front. To blunt the impact of free radicals (the name conjures images of bomb-throwing anarchists), living cells come equipped with a built-in system of antioxidizing mechanisms, a finely strung molecular web crafted over the eons since life began. That is not the kind of thing you want to mess with. And no creature would want to eliminate free radicals. They are scavengers that prevent the inevitable accretion of cellular poisons, garbage collectors for the cells. Beta-carotene, an antioxidant that gives carrots, mangoes, and papayas their color, has been promoted as having anticarcinogenic powers. But ina clinical trial in Finland, smokers given beta-carotene supplements were more likely to getlung cancer.A similar trial in the United States was curtailed at an early stage when it also appeared that the supplements were increasing the risk of the disease. “To go beyond the bounds of moderation is to outrage humanity”—Pascal again—and to outrage our cells.
    These days grocery store packaging has descended to a new level of detail, luring shoppers with produce and other goods rich inphytochemicals, naturally occurring ingredients in plants reputed to help detoxify carcinogens, repair DNA damage, or otherwise discourage cells from going wild. Lycopene, quercetin, resveratrol, silymarin, sulforaphane, indole-3-carbinol—they go in and out of style.In a laboratory dish these substances might affect biochemical pathways believed to be involved in the numbingly complex processes ofcarcinogenesis. Far less clear is whether consuming more of them actually prevents anyone from getting cancer. Unless a person is severely malnourished there is little reason to believe that a shortage of any specific molecule is throwing the cellular processes seriously out of whack. You can hedge your bets by takingmultivitamins, butthe evidence here is also meager. If life were so delicate we probably wouldn’t be here worrying about what we eat.
    There is so much that science doesn’t know about the molecular clockworks, and it is possible that substances in fruits and vegetables confer synergistic advantages whose logic is yet to be uncovered. Throughout the 1990s, the news was filled withreports of miraculous anticarcinogenic effects from consuming nature’s bounty. TheNational Cancer Institute began pushing its5 A Day program. Eat that many servings of fruits and vegetables and you would be a long way toward beating the odds against cancer.
    The evidence, alas, came mostly from case control studies in which people with and without cancer were asked to remember what they ate. Epidemiological studies like these are prone to error. Grasping to explain their predicament, cancer patients might be more likely to overestimate how badly they neglected their diets, while healthy people might remember eating more fruits and vegetables than they really did. Since cancers can take decades to develop, great feats of memory are required. Skewing things further,those most likely to volunteer for the control group may be relatively affluent health-conscious citizens who, in addition to eating nutritious meals, exercise more often and are less likely to binge on alcohol or cigarettes. A good study will try to strike a balance between the cases and the controls, but the best thatretrospective epidemiology can