內文
惡性腫瘤的生長是一個漫長而緩慢的過程，涉及三個關鍵步驟：細胞 DNA 中開始發生潛在癌變，促進受損細胞過度生長，以及癌變發展為腫塊並侵入其他組織。 初步證據表明，特定食物中的營養素會干擾這些步驟。
The growth of a malignant tumor is a long, slow process that involves three key steps: the initiation of potentially cancerous changes in a cell’s DNA, the promotion of uncontrolled growth in a damaged cell and the progression of a cancerous lesion into a mass that can invade other tissues. Preliminary evidence suggests that nutrients found in particular foods can interfere with each of these steps.
第 1 步：啟動 Step 1: Initiation
癌症風險 Cancer risk:
氧氣的代謝會產生稱為自由基的有毒物質，它會破壞細胞基因。
The processing of oxygen produces toxic agents called free radicals, which can damage a cell’s DNA.
飲食指引 Food tip:
抗氧化劑，例如綠茶中的多酚和番茄中的茄紅素，有助於中和自由基。 維生素 C、E 和 β-胡蘿蔔素也是很好的抗氧化劑。
Antioxidants, such as the polyphenols in green tea and the lycopene in tomatoes, help neutralize free radicals. Vitamin C, E and beta carotene are also good antioxidants.
*番茄可能有助於中和破壞基因的有毒物質
*Tomatoes may help neutralize toxic agents that damage DNA
致癌風險 Cancer risk:
大多數致癌化學物質以前致癌物進入人體。 為了成為能夠破壞基因的成熟致癌物，它們必須首先被肝臟產生的一階酶分解。
Most cancer-causing chemicals enter the body as procarcinogens. In order to become full-fledged carcinogens, capable of damaging cellular DNA, they must first be broken down by phase I enzymes produced in the liver.
飲食指引 Food tip:
大蒜含有稱為烯丙基硫化物的化學物質，有助於限制一階酶的產生。 除了一階酶，肝臟還會產生二階酶，以清除一階留下的危險殘留物。 青花菜、花椰菜和其他十字花科蔬菜富含一種叫做蘿蔔硫素的化學物質，可以促進二階酶的產生。
Garlic contains chemicals called allyl sulfides, which help limit the production of phase I enzymes. In addition to phase I enzymes, the liver produces phase II enzymes to cart off the dangerous residue phase I’s leave behind. Broccoli, cauliflower and other cruciferous vegetables are rich in a chemical called sulforaphane, which boosts production of phase II enzymes.
*大蒜有助於阻止致癌物的產生
*青花菜含有能去除細胞中的致癌物的化合物
*Garlic helps limit the production of cancer-causing chemicals
*Broccoli contains chemicals that remove carcinogens from cells
第 2 步：促進 Step 2: Promotion
癌症風險 Cancer risk:
如果一線防禦失敗且細胞發生潛在的癌變，人體最好的防禦就是摧毀它，或者阻止它快速分裂。 玉米油和紅花油中富含的 omega-6 脂肪酸可以促進細胞快速分裂。
If the first-line defenses fail and a cell undergoes potentially cancerous changes, the body’s best defense is to destroy it or, barring that, keep it from dividing rapidly. The omega-6 fatty acids that abound in corn oil and safflower oil seem to promote rapid cell division.
飲食指引 Food tip:
亞麻和多脂魚中的 omega-3 脂肪酸可通過將其他脂肪擠出細胞來阻止腫瘤生長。
The omega-3 fatty acids in flax and fatty fish may thwart tumor growth by crowding other fats out of cells.
*亞麻籽可以將壞脂肪鎖在細胞之外
*Flaxseed may lock bad fats out of cells
致癌風險 Cancer risk:
生殖組織特別容易罹癌，因為它們受性激素刺激時會迅速分裂。 如雌激素會促進女性乳腺細胞的快速生長。
Reproductive tissues are particularly cancer-prone because they divide rapidly when triggered by the body’s own sex hormones. Estrogen promotes fast growth of breast cells in women.
飲食指引 Food tip:
豆製品含有稱為異黃酮的化學物質，它能充當弱雌激素，降低強雌激素的作用。
Soy products contain chemicals called isoflavones, which act as weak estrogens and leave less room for strong ones.
*大豆可以保護生殖組織
*Soy may protect reproductive tissues
第 3 步：蔓延 Step 3: Progression
癌症風險 Cancer risk:
如果所有其他防禦都失敗並且受損細胞產生腫瘤，那麼問題是它是否會為自己建立血液供應並侵入周圍組織。 腫瘤細胞會釋放促進新血管發育的生長因子，一種稱為血管生成的過程。
If all other defenses fail and a damaged cell spawns a tumor, the question is whether it will build itself a blood supply and invade surrounding tissues. Tumor cells release growth factors that promote the development of new blood vessels, a
process known as angiogenesis.
飲食指引 Food tip:
所謂的 cox-2 抑製劑，例如紅葡萄中的白藜蘆醇和薑黃中的薑黃素，會抑制腫瘤生長因子的產生。
So-called cox-2 inhibitors, such as the resveratrol in red grapes and the curcumin in turmeric, may suppress the tumor’s production of growth factors.
*紅葡萄可能會抑制血管生長
*Red grapes may inhibit blood vessel growth
食物與這一切有什麼關係？ 據估計是相當的多。 “人類每天要吃掉兩到三磅的食物。” Koo 說。 “這是我們與環境最大的接觸。” 人口研究一直將高植物飲食與低癌症風險聯繫起來。 而分子生物學家在過去十年中發現，這些食物中所含的化合物可以以非常特殊的方式阻止腫瘤的發展。 沒有人認為綠茶和大蒜足以治療晚期疾病。 新的預防飲食的目標是減少對此類治療的需求。 正如 Gaynor 所說，吃正確的食物 “能在癌症開始之前阻止癌症，就如同繫好安全帶能降低發生致命車禍的風險。”
What does food have to with all of this? Quite a bit, by most estimates. “Humans eat two to three pounds of food into their bodies every day,” says Koo. “It’s our greatest contact with the environment.” Population studies have consistently linked a high intake of plant foods with a low risk of cancer. And as molecular biogists have discovered during the past decade, the compounds contained in those foods can work in very specific ways to block the development of tumors. No one is holding up green tea and garlic as adequate treatments for advanced disease. The goal of the new prevention diets is to reduce the need for such treatments. As Gaynor puts it, eating the right foods is “as specific to stopping cancer before it starts as wearing a seat belt to lowering your risk of a fatal automobile accident.”
水果和蔬菜富含抗氧化劑。 維生素 C、E 和 β 胡蘿蔔素都可以幫助中和會降解細胞 DNA 的自由基。 它們甚至有助於互相保護，C 防止 E 的氧化損傷，E 阻止 β-胡蘿蔔素的氧化。 但是維生素只是抗氧化故事的開始。 研究人員最近發現了幾種可能具有更強影響力的植物化學物質。 葡萄和紅酒富含一種叫做白藜蘆醇的抗氧化劑，在最近的一項研究中，白藜蘆醇使小鼠皮膚腫瘤的發病率降低了 88%。 綠茶含有多種有效的抗氧化化學物質，稱為多酚。 研究人員估計，其中一種名為 EGCG 的化合物的自由基淬滅效果是維生素 E 的 20 倍，是維生素 C 的 500 倍。
Fruits and vegetables are loaded with antioxidants. Vitamins C, E and beta carotene can all help neutralize the free radicals that degrade cellular DNA. They even help protect each other, C preventing oxidative damage to E, and E blocking the oxidation of beta carotene. But vitamins are just the beginning of the antioxidant story; researchers have recently identified several plant chemicals that may have far stronger effects. Grapes and red wine are rich in an antioxidant called resveratrol, which reduced the incidence of skin tumors in mice by 88 percent in one recent study. Green tea contains several potent antioxidant chemicals known as polyphenols. Researchers estimate that one of them, a compound called EGCG, has 20 times the radical-quenching effect of vitamin E, and 500 times the effect of vitamin C.
然後是番茄紅素，這種色素使番茄呈現紅色。 你不能從生番茄中獲得太多的番茄紅素； 它被水果的蛋白質和纖維緊密結合。 但是烹飪可以釋放它以供人體吸收，而脂肪有助於將其帶入血液。 如果這還不足以作為享受搭配少許橄欖油的番茄醬的理由，那麼聽聽這個。 在 1995 年對 48,000 名男性的研究中，哈佛大學的研究人員發現那些每週吃 10 份富含番茄的食物的人患有前列腺癌的風險降低了接近一半。 其他研究表明，番茄紅素有助於預防乳癌、肺癌和消化道癌症。
Then there’s lycopene, the pigment that gives tomatoes their blush. You can’t get much lycopene from a raw tomato; it’s too
tightly bound by the fruit’s proteins and fibers. But cooking frees it for absorption by the body, and dietary fat helps carry it into the bloodstream. If that’s not reason enough to enjoy some tomato sauce with a dash of olive oil, consider this. In a 1995 study of 48,000 men, Harvard researchers found that those who ate 10 servings of tomato-rich foods every week cut their risk of prostate cancer by nearly half. Other studies suggest that lycopene may help ward off cancers of the breast, lung and digestive tract.
如果你做番茄醬，別忘了加些大蒜。 正如番茄紅素有助於抵禦氧化損傷一樣，大蒜、細香蔥和洋蔥中的烯丙基硫化物有助於身體更安全地處理致癌化學物質。 當潛在致癌物進入人體時，肝臟的一階酶會分解它們，使它們處於更具反應性的狀態，直到它們被二階酶運走。 烯丙基硫化物可以調節一階酶活性，可以減少我們的細胞需要應對的雜質。 “即使飲食中的少量大蒜也會對新陳代謝產生顯著影響。” 賓州大學的營養學家 John Milner 說。 你不必煮丁香來獲得效果，但烯丙基硫化物不會完全形成，除非你將它切碎並靜置 10 分鐘。 米爾納建議購買陳年大蒜提取物，這種提取物在實驗室研究中顯示出最強功效。
If you do make tomato sauce, don’t forget to add some garlic. Just as lycopene helps ward off oxidative damage, the allyl sulfides found in garlic, chives and onions may help the body process cancer-causing chemicals more safely. You’ll recall that the liver’s phase I enzymes break down potential carcinogens as they enter the body, leaving them in a more reactive state until they’re carted away by phase II enzymes. Allyl sulfides can modulate phase I activity, presumably reducing the volume of debris that our cells have to contend with. “Even modest amounts of garlic in the diet have a marked impact on metabolism,” says nutritionist John Milner of Pennsylvania State University. You don’t have to cook the clove to get the effect, but the allyl sulfides won’t fully form unless you cut it up and let it sit for 10 minutes. Milner suggests buying aged garlic extract, which has shown the most potency in lab studies.
大蒜並不是唯一可以幫助您更巧妙處理致癌物的食物。 正如大蒜可以抑制一階酶活性一樣，西蘭花、花椰菜和捲心菜等十字花科蔬菜可以促進二階酶的產生，從而清除化學碎片。 這要歸功於蘿蔔硫素，這是一種味道辛辣的化學物質，它具有驅蟲作用。 約翰·霍普金斯大學藥理學家 Paul Talalay 萊六年前發現，蘿蔔硫素可以激活一種基因，促進重要的二階酶產生。 為了測試它的保護作用，他給老鼠注射了一種叫做 DMBA 的強致癌物質，並給其中一些老鼠注射了蘿蔔硫素。 68% 未經治療的動物長出腫瘤，而接受高劑量蘿蔔硫素的動物中只有 26% 生病。 這是否證明西蘭花可以預防人類癌症？ 當然不是，但它提供了一個很好的藉口來吃一些。
Garlic isn’t the only food that could help you handle carcinogens more deftly. Just as garlic can dampen phase I activity, cruciferous vegetables such as broccoli, cauliflower and cabbage may boost production of the phase II enzymes that cart away chemical debris. The credit goes to sulforaphane, a sharp-tasting chemical that insects (and some humans) find repellent. Johns Hopkins pharmacologist Paul Talalay discovered six years ago that sulforaphane could activate a gene that boosts production of important phase II enzymes. To test its protective effects he injected rats with a potent carcinogen called DMBA, and gave some of them sulforaphane as well. Tumors cropped up in 68 percent of the untreated animals, yet only 26 percent of those on high doses of sulforaphane got sick. Does that prove that broccoli prevents cancer in people? Of course not, but it provides a good excuse to munch some.
假如綠茶、紅酒、西紅柿、大蒜和西蘭花都不足以讓您的某個細胞免於失控。 其他食物能影響癌前病變發展成腫瘤的機率嗎？脂肪可能發揮重要作用。 Memorial Sloan-Kettering 的泌尿科醫生 William Fair 博士指出，癌前前列腺病變在全世界同樣普遍。 屍檢研究發現，在 30 多歲的所有男性中，近三分之一都有這種情況。 然而，晚期腫瘤在美國（脂肪佔卡路里的近 40%）是日本（脂肪佔卡路里的不到 20%）的六倍。乳癌的發病率遵循類似的模式。實驗室研究表明，腫瘤細胞在低脂肪飲食的動物中表現得不如那些餵食高脂肪食物的動物具有侵略性。
It also points to the need for seeking other safeguards. Suppose the green tea and red wine, the tomatoes, the garlic and the broccoli aren’t enough to keep one of your cells from running amok. Could other foods affect the odds that a precancerous lesion will blossom into a tumor? Dietary fat may play an important role. Precancerous prostate lesions are equally common throughout the world, notes Dr. William Fair, a urologist at Memorial Sloan-Kettering. Autopsy studies find them in nearly a third of all men in their 30s. Yet advanced tumors are six times more common in the United States (where fat accounts for nearly 40 percent of calories than in Japan (where it accounts for les than 20 percent). Breast-cancer incidences follows a similar pattern. And lab studies have shown that tumor cells behave less aggressively in animals on low-fat diet than in those fed higher-fat fare.
但總脂肪攝入量只是故事的一部分。 許多專家現在都認為，您消耗的脂肪類型與數量一樣重要。 飽和脂肪，儘管它對心臟和血管會造成破壞，似乎並沒有以某種方式影響癌症風險……
But total fat intake is only part of the story. Many experts now agree that the type of fat you consume is as important as the amount. Saturated fat, for all-the havoc it wreaks on the heart and blood vessels, doesn’t seem to affect cancer risk one way…
NEWSWEEK NOVEMBER 30, 1998
