Rating cancer risks.[ILLUSTRATION OMITTED] What causes cancer? Cigarette smoking is the number-one culprit. But in 1981, Richard Doll Sir William Richard Shaboe Doll CH OBE FRS (28 October 1912–24 July 2005) was a British physiologist who became the foremost epidemiologist of the 20th century, turning the subject into a rigorous science. He was a pioneer in research linking smoking to health problems. and Richard Peto Sir Richard Peto, FRS (born 1943) is Professor of Medical Statistics and Epidemiology at the University of Oxford. He attended Richard Taunton's School in Southampton and subsequently studied Natural Sciences at Cambridge University. , both then of Oxford University in England, estimated that 30 to 35 percent of cancers are caused by diet. More than two decades later, "that estimate is still in right ballpark," says Walter Willett Dr. Walter Willett, MD, DrPH., (born in 1945 in Hart, Michigan[1]) is an American physician and nutrition researcher. Currently, Dr. Willett is the Fredrick John Stare Professor of Epidemiology and Nutrition in the Department of Nutrition and Epidemiology at Harvard , who heads the department of nutrition at the Harvard School of Public Health The Harvard School of Public Health is (colloquially, HSPH) is one of the professional graduate schools of Harvard University. Located in Longwood Area of the Boston, Massachusetts neighborhood of Mission Hill, next to Harvard Medical School and Cambridge, Massachusetts, in Boston. But the blame for causing cancer--and the credit for perventing it--has shifted to different foods and other factors over the years. That's the conclusion of the Second Expert Report on Food, Nutrition, Physical Activity, and the Prevention of Cancer: a Gloval Perspective, released in November by the American Institute for Cancer Research and World Cancer Research Fund. After five years of reviewing the results of 7,000 studies, the report's international panel of experts rated the cancer risks from obesity, inactivity, meat, alcohol, and more. They started with half a million studies. Nine research teams--each with 5 to 20 researchers from institutions like Johns Hopkins University Johns Hopkins University, mainly at Baltimore, Md. Johns Hopkins in 1867 had a group of his associates incorporated as the trustees of a university and a hospital, endowing each with $3.5 million. Daniel C. and the University of Bristol in England--weeded out studies that were irrelevant or inadequate. That left a panel of 21 international experts with 7,000 studies on 17 kinds of cancer and 61 "exposures," from red meat to sugary sug·ar·y adj. sug·ar·i·er, sug·ar·i·est 1. Characterized by or containing sugar: sugary foods. 2. Tasting or looking like sugar. 3. drinks, fast foods, and fruits ... and from body fatness to breastfeeding, television viewing, and sedentary sedentary /sed·en·tary/ (sed´en-tar?e) 1. sitting habitually; of inactive habits. 2. pertaining to a sitting posture. sedentary of inactive habits; pertaining to a fat, castrated or confined animal. living. Harvard's Walter Willett served on the panels that drew up the 2007--and the 1997--Report on Food, Nutrition, Physical Activity, and the Prevention of Cancer. Here he explains the panel's advice, and how it has changed over the last 10 years. Q: What has changed since the last report? A: One of the biggest changes is that the report emphasizes much more strongly the importance of overweight as a factor in cancer, which comes as no surprise given all the evidence that's come in since the 1997 report. If you don't smoke, the single most important thing you can do to prevent cancer is to keep your weight under control. The best way to do that if you're a young adult and not already overweight is to be on the lookout for in search of; looking for. See also: Lookout even a three-or four-pound gain in weight. Q: A few extra pounds boost your risk? A: No, but they mean you're on the track to gaining much more weight, which will put you at high risk of many cancers. A few extra pounds are a signal that now is the time to either make some corrections in the way you're eating or increase your level of physical activity, and preferably do some of both. Most people become overweight or obese by gaining a couple of pounds a year. Q: Which cancers are linked to obesity? A: The list is growing. We've known about endometrial cancer Endometrial Cancer Definition Endometrial cancer develops when the cells that make up the inner lining of the uterus (the endometrium) become abnormal and grow uncontrollably. for a long time, but now colon, kidney, pancreatic, and postmenopausal post·men·o·paus·al adj. Of or occurring in the time following menopause. postmenopausal Change of life Gynecology adjective Referring to the time in ♀ when menstrual periods stop for ≥ 1 yr breast cancers and adenocarcinoma adenocarcinoma: see neoplasm. of the esophagus esophagus (ĭsŏf`əgəs), portion of the digestive tube that conducts food from the mouth to the stomach. When food is swallowed it passes from the pharynx into the esophagus, initiating rhythmic contractions (peristalsis) of the are all well-established. And new evidence from the large American Cancer Society American Cancer Society, n.pr established in 1913, this national volunteer-based health organization is committed to the elimination of cancer through prevention and treatment and to diminishing cancer suffering through advocacy, scholarship, research, study suggests that the risk of some lymphomas and leukemias may be increased by overweight as well. So the list is long, and it keeps getting longer. Q: What about prostate cancer prostate cancer, cancer originating in the prostate gland. Prostate cancer is the leading malignancy in men in the United States and is second only to lung cancer as a cause of cancer death in men. ? A: That's a little more complicated. In men over age 65 there probably is some association with overweight, but it's not as clear as most of the other cancers. Q: Is it easier to keep weight off than to lose weight? A: That's an important point. Once you've gained weight, it's harder to take it off. Even your body composition has changed. Your bones have gotten bigger to carry around the extra weight. And you may have gotten arthritis or angina Angina Definition Angina is pain, "discomfort," or pressure localized in the chest that is caused by an insufficient supply of blood (ischemia) to the heart muscle. , which would make it much harder to exercise to take off weight. Q: What if you're already overweight? A: At any time in life, it helps to lose weight if you're overweight. Most people can't get all the way back to where they were at age 21, even though that might be their ideal weight. But even a 5 to 10 percent weight loss can be important. For example, last year we reported in the Nurses' Health Study Nurses' Health Study Cardiology A large cohort study that evaluated the effect of exogenous HRT on the risk of cardiovascular disease. See Estrogen replacement therapy, Osteoporosis. that among women who never used postmenopausal hormones, those who lost at least 22 pounds since menopause had a 57 percent lower risk of breast cancer than those who didn't lose weight. Q: And cancer risk starts to rise before you're obese? A: Right. For almost all of these cancers, the increased risk starts even before you cross the line between normal and overweight. That's why the panel recommends being as lean as possible within the normal range. And for breast cancer in postmenopausal women, it looks like the strongest relationship is with the amount of weight gained after age 18. Q: Why? A: Unless you're doing serious body building, weight gain after age 18 is almost all fat. Weight change also takes into account your own frame. Some people are clearly more heavily framed or more muscular. So a change in weight is more important than whether you're overweight according to according to prep. 1. As stated or indicated by; on the authority of: according to historians. 2. In keeping with: according to instructions. 3. a body mass index chart [see p. 7]. Q: How might obesity cause cancer? A: The reasons are probably different for different cancers. For endometrial endometrial /en·do·me·tri·al/ (en?do-me´tre-il) pertaining to the endometrium. endometrial, n relating to the end-ometrium or cavity of the uterus. and postmenopausal breast cancer, for example, it's clear that being overweight leads to high estrogen levels, though high insulin levels might contribute. For colon cancer colon cancer, cancer of any part of the colon (often called the large intestine). Colon cancer is the second most common cancer diagnosed in the United States. , there's a strong hypothesis for high insulin increasing the risk. But, if anything, estrogens Estrogens Hormones produced by the ovaries, the female sex glands. Mentioned in: Acne, Polycystic Ovary Syndrome estrogens (es´trōjenz), n. seem to reduce the risk of colon cancer. And for adenocarcinoma of the esophagus, it may be the gastric reflux gastric reflux n. See gastroesophageal reflux. that people get when they're overweight. And there's a hypothesis that obesity promotes inflammation, which raises the risk of several cancers, but it's far too early to say. Q: Did the panel took at how to lose--or not gain--weight? A: Yes. The report makes a strong and important statement that soda consumption and sugary drinks promote weight gain. And there's a recommendation to limit calorie-dense foods. That was defined as foods with more than 65 to 80 calories per ounce. I think the panel was thinking of refined sugars, starches, and fats. But the bottom line is to limit calories. Q: Isn't being active good even if you don't Even If You Don't is a single released by the band Ween in 2000 on Mushroom Records. Formats Enhanced CD single Includes the quicktime video of "Even If You Don't" directed by Matt Stone & Trey Parker of "South Park". lose weight? A: Yes. Inactivity increases the risk of both breast and colon cancer. And there's a recommendation to limit sedentary habits like watching TV. Fruits & Vegetables Q: How else has the advice changed? A: There's a de-emphasis on fruits and vegetables, which had been right at the top before. It's still there, but before, we thought there was probable or convincing evidence that fruits and vegetables could reduce the risk of a long list of cancers. Now it's mostly for mouth, throat, and esophageal cancer Esophageal Cancer Definition Esophageal cancer is a malignancy that develops in tissues of the hollow, muscular canal (esophagus) along which food and liquid travel from the throat to the stomach. . The main problem is that only retrospective case-control studies case-control study, n an investigation employing an epidemiologic approach in which previously existing incidents of a medical condition are used in lieu of gathering new information from a randomized population. were available for the 1997 report. Q: Those studies compare what cancer patients and healthy people remember eating in the past? A: Yes. And we knew all along that there was a potential for bias because the healthy people who participate in those studies tend to be more health conscious. They have a higher fruit and vegetable intake, and that makes it look like the cases--the cancer patients--have low fruit and vegetable consumption. Q: Shouldn't we eat fruits and vegetables for other reasons? A: Yes, that's important. Even though the evidence is downgraded a bit for cancer, the evidence has gotten stronger for cardiovascular disease Cardiovascular disease Disease that affects the heart and blood vessels. Mentioned in: Lipoproteins Test cardiovascular disease , so I would just as strongly promote generous consumption of fruits and vegetables. However, I would take fruit juices out of the list because there's increasing evidence that their sugar is deleterious deleterious adj. harmful. . We're seeing an increased risk of diabetes with higher fruit juice consumption. I think one small glass a day is okay, but not more. Meat & Dairy Q: What about red meat? A: The evidence is convincing that red meat increases the risk of colon cancer. The report recommends that people who eat red meat consume less than 18 ounces a week, and that little or none of it should be processed meat like ham, bacon, pastrami, or salami. Sausage and hot dogs are also processed meats if they're made with nitrites or nitrates. And beyond cancer, there's very clear evidence that replacing red meat with a combination of fish, poultry, and nuts can lower the risk of cardiovascular disease. There's also quite a bit of evidence that high red meat consumption can increase the risk of diabetes. For both colon cancer and diabetes, the association is considerably stronger for processed meats than for fresh red meats. Q: There's no advice about poultry or seafood? A: No, because there's no evidence that they raise or lower the risk of cancer. Q: Why no advice about dairy, when the panel concluded that high-calcium diets promote prostate cancer? A: There's also evidence that calcium supplements lower the risk of colon cancer, so that makes it complicated to give clear directions. In my view, it makes sense for men to have a low-to-moderate intake of dairy, because we know of other ways to greatly reduce colon cancer risk, and we don't know Don't know (DK, DKed) "Don't know the trade." A Street expression used whenever one party lacks knowledge of a trade or receives conflicting instructions from the other party. much about preventing prostate cancer. Q: How might calcium harm the prostate? A: High calcium suppresses 1,25 hydroxy-vitamin D, which is the biologically active form of vitamin D vitamin D Any of a group of fat-soluble alcohols important in calcium metabolism in animals to form strong bones and teeth and prevent rickets and osteoporosis. It is formed by ultraviolet radiation (sunlight) of sterols (see steroid) present in the skin. . Low vitamin D levels may increase cancer risk. Q: But the panel wasn't convinced that vitamin D prevents cancer? A: If the report included studies published in the last year, there might have been enough evidence, because more data are available now. I think a re-review of the vitamin D studies would move colon cancer from the "limited decreased risk" into the "probable decreased risk" category. [ILLUSTRATION OMITTED] The American Institute for Cancer Research has made a commitment to do more frequent updating of the entire report, rather than wait another 10 years. The evidence on diet and cancer is accumulating quite fast now. Q: Should men take selenium selenium (səlē`nēəm), nonmetallic chemical element; symbol Se; at. no. 34; at. wt. 78.96; m.p. 217°C;; b.p. about 685°C;; sp. gr. 4.81 at 20°C;; valence −2, +4, or +6. to prevent prostate cancer? A: The panel didn't recommend taking any supplements, but it did conclude that there's probable evidence that selenium decreases the risk. That's largely because a randomized ran·dom·ize tr.v. ran·dom·ized, ran·dom·iz·ing, ran·dom·iz·es To make random in arrangement, especially in order to control the variables in an experiment. trial showed benefit for prostate cancer, although the trial was small. On the other hand, there's a large randomized trial going on with selenium, and if the benefit had been as large and as fast as it was in the small trial, the large trial would have been stopped by now. Otherwise, it would be unfair to the men taking the placebo. So selenium may not reduce prostate cancer risk dramatically. Alcohol Q: Is alcohol a problem only in large amounts? A: No. With breast cancer, it's clear that even one drink a day can significantly increase risk. For colon cancer, it looks like there's an increased risk at two or more drinks a day. But for liver cancer Liver Cancer Definition Liver cancer is a relatively rare form of cancer but has a high mortality rate. Liver cancers can be classified into two types. , the risk is increased at over two drinks a day. For mouth and throat cancer, most of the evidence also comes from higher intakes. And, most importantly Adv. 1. most importantly - above and beyond all other consideration; "above all, you must be independent" above all, most especially , the higher risk of mouth and throat cancer is largely seen in smokers. There's some increased risk among non-smokers, but only with really high intakes. Q: But alcohol might lower the risk of heart disease? A: Yes. It very substantially reduces heart disease risk if you have one or two drinks a day. But it also causes traffic accidents, induces over-drinking, and increases the risk of some cancers. So it's complicated. There is no health reason for younger people to drink alcohol, but one or two drinks a day might be beneficial for some middle-aged or older people who are not disposed to alcoholism. Fiber & Salt Q: Does fiber reduce the risk of colon cancer? A: I think the evidence is at the margin, and in the last year, more data have come along that don't support the relationship. But that doesn't bother me too much because there's already good evidence that whole-grain, high-fiber foods reduce risk of cardiovascular disease. So whether people eat more fiber-rich foods because of colon cancer or cardiovascular disease doesn't make much difference. It will help them either way. Q: Why does the report recommend limiting salt? A: Salt appears to raise the risk of stomach cancer, which is less common here than in underdeveloped un·der·de·vel·oped adj. Not adequately or normally developed; immature. countries. But cutting salt should also help protect against cardiovascular disease. Diet & Cancer The Panel's Conclusions Food, Nutrition, Physical Activity, and the Prevention of Cancer: a Global Perspective used a more detailed version of this graphic to summarize the evidence on diet, exercise, and cancer. Look across each row to find out about the evidence for a given cancer. Look up from the bottom of each column to find out which cancers are influenced by specific foods, exercise, or other "exposures." Factors that increase the risk of cancer are in shades of Noun 1. shades of - something that reminds you of someone or something; "aren't there shades of 1948 here?" reminder - an experience that causes you to remember something red; factors that decrease the risk are in shades of blue. (The panel used white to indicate factors that are unlikely to affect cancer risk.) The taller the block and the darker the color, the stronger the evidence. According to the panel, the evidence was called convincing if it was "strong and unlikely to change in the future" and probable if the link with cancer was "very likely." Limited meant that the evidence, though scanty, suggested a link. It's the "watch this space" (for more news) grade, said the panel. The full 500-page report can be viewed or downloaded for free at www.dietandcancerreport.org. [GRAPHIC OMITTED] Advice For You The panel issued "personal recommendations" for individuals and "public health goals" for countries to prevent cancer. Here's an abridged (and slightly edited) version of the advice for individuals. BODY FATNESS Be as lean as possible within the normal range of body weight Avoid weight gain and increases in waist circumference after age 21. PHYSICAL ACTIVITY Be physically active as part of everyday life Be moderately physically active, equivalent to brisk walking, for at least 30 minutes every day. As fitness improves, aim for 60 minutes or more of moderate, or for 30 minutes or more of vigorous, physical activity every day. Limit sedentary habits such as watching television. FOODS AND DRINKS THAT PROMOTE WEIGHT GAIN Limit consumption of calorie-dense foods Avoid sugary drinks Consume calorie-dense foods sparingly spar·ing adj. 1. Given to or marked by prudence and restraint in the use of material resources. 2. Deficient or limited in quantity, fullness, or extent. 3. Forbearing; lenient. and fast food sparingly, if at all. (Fast foods are any calorie-dense convenience foods that are consumed frequently and in large portions.) Avoid sugary drinks (like soda) and limit fruit juices. PLANT FOODS Eat mostly foods of plant origin Eat at least five daily servings (at least 14 oz.) of a variety of fruits and vegetables (excluding starchy starch·y adj. starch·i·er, starch·i·est 1. a. Containing starch. b. Stiffened with starch. 2. Of or resembling starch. 3. vegetables like potatoes and sweet potatoes sweet potato, trailing perennial plant (Ipomoea batatas) of the family Convolvulaceae (morning glory family), native to the New World tropics. Cultivated from ancient times by the Aztecs for its edible tubers, it was introduced into Europe in the 16th cent. ). Limit refined starchy foods (white bread, white rice, etc.). Eat relatively unprocessed grains and/or beans with every meal. ANIMAL FOODS Limit intake of red meat and avoid processed meat People who eat red meat (beef, pork, lamb) should consume less than 18 oz. a week. Very little, if any, should be processed meats (like ham, bacon, pastrami, salami, and--if they contain nitrates or nitrites--sausages and hot dogs). ALCOHOLIC DRINKS Limit alcoholic drinks If alcoholic drinks are consumed, limit consumption to no more than two drinks a day for men and one drink a day for women. PRESERVATION, PROCESSING, PREPARATION Limit consumption of salt Avoid salt-preserved, salted, or salty foods. Limit consumption of processed foods with added salt to ensure an intake of less than 2,400 mg of sodium a day. DIETARY SUPPLEMENTS Noun 1. dietary supplement - something added to complete a diet or to make up for a dietary deficiency diet - a prescribed selection of foods vitamin pill - a pill containing one or more vitamins; taken as a dietary supplement Aim to meet nutritional needs through diet alone Dietary supplements are not recommended for cancer prevention. BREASTFEEDING Aim to breastfeed breast·feed or breast-feed v. breast-fed , breast-feed·ing, breast-feeds v.tr. To feed (a baby) mother's milk from the breast; suckle. v.intr. To breastfeed a baby. infants exclusively up to six months and continue as they start eating food CANCER SURVIVORS Cancer survivors are those individuals with cancer of any type, current or past, who are still living. The National Coalition for Cancer Survivorship (NCCS) pioneered the definition of survivor as from the time of diagnosis and for the balance of life, a person diagnosed with Follow the recommendations for cancer prevention for diet, healthy weight, and physical activity [ILLUSTRATION OMITTED] Walter C. Willett is a professor of epidemiology and nutrition and chair of the department of nutrition at the Harvard School of Public Health. He is also a professor of medicine at Harvard Medical School Harvard Medical School (HMS) is one of the graduate schools of Harvard University. It is a prestigious American medical school located in the Longwood Medical Area of the Mission Hill neighborhood of Boston, Massachusetts. . Willett has co-authored more than 1,000 studies and four books Four Books Chinese Sishu Ancient Confucian texts used as the basis of study for civil service examinations (see Chinese examination system) in China (1313–1905). , including Eat, Drink and be Healthy: The Harvard Medical School Guide to Healthy Eating. He spoke to Nutrition Action's Bonnie bon·ny also bon·nie adj. bon·ni·er, bon·ni·est Scots 1. Physically attractive or appealing; pretty. 2. Excellent. Liebman by phone from Boston.
BODY MASS INDEX (BMI)
19 20 21 22 23 24
4'10" 91 96 100 105 110 115
4'11" 94 99 104 109 114 119
5'0" 97 102 107 112 118 123
5'1" 100 106 111 116 122 127
5'2" 104 109 115 120 126 131
5'3" 107 113 118 124 130 135
5'4" 110 116 122 128 134 140
5'5" 114 120 126 132 138 144
5'6" 118 124 130 136 142 148
5'7" 121 127 134 140 146 153
5'8" 125 131 138 144 151 158
5'9" 128 135 142 149 155 162
5'10" 132 139 146 153 160 167
5'11" 136 143 150 157 165 172
6'0" 140 147 154 162 169 177
6'1" 144 151 159 166 174 182
6'2" 148 155 163 171 179 186
6'3" 152 160 168 176 184 192
6'4" 156 164 172 180 189 197
NORMAL
BODY MASS INDEX (BMI)
25 26 27 28 29 30 35 40
4'10" 119 124 129 134 138 143 167 191
4'11" 124 128 133 138 143 148 173 198
5'0" 128 133 138 143 148 153 179 204
5'1" 132 137 143 148 153 158 185 211
5'2" 136 142 147 153 158 164 191 218
5'3" 141 146 152 158 163 169 197 225
5'4" 145 151 157 163 169 174 204 232
5'5" 150 156 162 168 174 180 210 240
5'6" 155 161 167 173 179 186 216 247
5'7" 159 166 172 178 185 191 223 255
5'8" 164 171 177 184 190 197 230 262
5'9" 169 176 182 189 196 203 236 270
5'10" 174 181 188 195 202 207 243 278
5'11" 179 186 193 200 208 215 250 286
6'0" 184 191 199 206 213 221 258 294
6'1" 189 197 204 212 219 227 265 302
6'2" 194 202 210 218 225 233 272 311
6'3" 200 208 216 224 232 240 279 319
6'4" 205 213 221 230 238 246 287 328
OVERWEIGHT OBESE
Source: National Heart, Lung, and Blood Institute.
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