Vegetables and colon cancer.
Total vegetables and total colon cancer risk.
Data about the relation between total vegetables and total colon cancer risk was provided by a pooled analysis of 14 cohorts and 6 additional cohorts,
including a total of > 9,847 cases (the amount of cases was not defined in one cohort of very large size: Park Y [27]).
A significant protective effect among men, but not women, was found in one cohort of very large size (Nomura AM [30]). No other (non)significant
associations were found. The average RR = 0.94 (excluding incomplete data from Park Y [27]).
Inclusion of intermediate levels of consumption:
Among men, (non)significant protective effects were found in the 2nd-5th quintile of consumption (median 212 - median 539 g/d) in one cohort of very
large size (Park Y). And a significant protective effect was found in the 3rd quintile of consumption (median 336 g/d) in another cohort of very large size
(Nomura AM).
Among women, no (non)significant effects were found at any level of consumption in any cohort.
Effect modification:
- No effect modification was found by age at diagnosis (29), follow-up period (29), multivitamin supplement use (25, 29), having had a sigmoidoscopy or colonoscopy, or a polyp detected (6), HRT use (7), alcohol consumption (15, 25), meat consumption (18, 25), and physical activity (25).
- Most (6, 7, 25), but not all (18) cohorts showed no effect modification by smoking status.
- Most (6), but not all (8) cohorts showed no effect modification by family history of colorectal cancer.
- Most (15, 25), but not all (18) cohorts showed no effect modification by BMI.
Conclusion: Few effects were seen. No evidence was found for an association between total vegetables and total colon cancer risk. But among men, a protective effect at an intermediate levels of consumption is suggested (median intake 336 g/day). Lack of specific data about amounts of cases prevents indication of the level of evidence, but this evidence probably is suggestive. No evidence was found for effect modification.
| Author | Cohort name | Cases | Relative Risk (RR) |
|---|---|---|---|
| 30) Nomura AM (2008) | The Multiethnic Cohort Study | 734 men, and 617 women | Men: RR = 0.80 (0.63-1.03; P = 0.039). Women: RR = 0.90 (0.70-1.17; P = 0.624). |
| 29) Koushik A (2007) | Pooled analysis of 14 cohort studies | 1,890 men, and 3,947 women | Men: RR = 0.98 (0.76-1.25; P = 0.11). Women: RR = 0.95 (0.81-1.11; P = 0.73). |
| 27) Park Y (2007) | The NIH-AARP Diet and Health Study | Not defined | Men: RR = 0.84 (0.71-0.99; P = 0.11). Women: RR = 1.10 (0.86-1.40; P = 0.50). |
| 25) Tsubono Y (2005) | The JPHC Study | 300 men, and 156 women | Men: RR = 1.24 (0.86-1.79; P = 0.69). Women: RR = 1.01 (0.58-1.76; P = 0.96). |
| 24) Sato Y (2005) | The Miyagi Cohort Study | 173 (not defined stratified by gender) | Men: RR = 1.00 (0.56-1.77; P = 0.91). Women: RR = 1.65 (0.78-3.49; P = 0.13). |
| 18) van Duijnhoven FJ (2009) | The EPIC Study | 1,828 | HR = 0.85 (0.71-1.02; P = 0.11). |
| 1) Shibata A (1992) | The Leisure World Study | 97 men, and 105 women | Men: RR = 1.39 (0.84-2.30). Women: RR = 0.72 (0.45-1.16). |
| Total number of cases: 9,847 + X | Average RR = 0.94 |
| Author | Cohort name | Subjects | Years of follow-up | Cases | End point | Consumption of | Relative Risk (RR) | Adjustments | ||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
| 30) Nomura AM (2008) | The Multiethnic Cohort Study. | 85,903 men and 105,108 women aged 45-75. (Hawaii and California) | 7.3 (1993-96 to 2001) | 734 men, and 617 women | Colon cancer risk (only invasive adenocarcinoma) | Vegetables (not defined) |
Age, family history of colorectal cancer, history of colorectal polyp, pack-years of cigarette smoking, BMI, hours of vigorous activity, aspirin use, multivitamin use, replacement hormone use, log energy intake, alcohol, red meat, folate, vitamin D, and calcium. |
29) Koushik A. (2007) | Pooled Analysis of 14 Cohort Studies. | 756,217 subjects (242,362 men and 513,855 women) | 6-20 years | 5837 (3947 women, 1890 men) | Colon cancer risk | Total vegetables (Vegetables and vegetable juices. Excluding potatoes and mature beans) |
INCLUSION CRITERIA: |
In the analysis, an extended follow-up period for most of the studies was included:
RELATIVE RISK:
BMI; height; education; physical activity; family history of colorectal cancer; postmenopausal hormone use; oral contraceptive use; use of nonsteroidal anti-inflammatory drugs; multivitamin use; smoking habits (never/past/current + amount); red meat; total milk; alcohol; and total energy. Age in years and year of questionnaire return were included as stratification variables. |
27) Park Y. (2007) | The NIH-AARP Diet And Health Study. | 488,043 (291,094 men and 196,949 women) aged 50-71. | (USA) 4,3 | (1996-2000) No data shown. | (2,972 for total colorectal cancer risk ([2,048 men and 924 women]) Colon cancer risk | Vegetables (Not defined. Excluding potatoes except sweet potatoes) |
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One serving = 1 cup of leafy vegetables, 1/2 cup of other vegetables, or 6 ounces of juice (1 cup = 237 mL, 1 ounce = 29.6 mL). education, physical activity, smoking (smoking/past/current. And < or = 20 vs > 20 cigarettes/day), alcohol, red meat, dietary calcium, total energy. |
Additional adjustment for race; BMI; family history of colorectal cancer; colorectal cancer screening; use of multivitamins, NSAID's, and menopausal hormone therapy in women; and vitamin D intake showed similar results. Mutual adjustment for intakes of fruits and vegetables did not change the results. Adjustment for dietary fiber did not change the results. 25) Tsubono Y. (2005) | The JPHC Study. | A pooled analysis of 2 prospective studies with 88,658 Japanese men and women. | Cohort I included 40,106 subjects 40-59 years (19,345 men and 20,761 women). Cohort II included 48,552 subjects 40-69 years (23,180 men and 25,372 women). Cohort I: 9 (1990-99). | Cohort II: 6 (1993-99) 456 | (300 men, 156 women) Colon cancer risk | Total vegetables | Cohort I: five vegetables (green leafy, yellow, white, pickled, and vegetable juice). Cohort II: six vegetables (green vegetables, carrot, tomatoes, green pickled vegetables, other pickled vegetables, and vegetable juice)
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Stratified analyses by covariates included in multivariate models did not reveal remarkable effect modifications (no data shown). Analyses based on the octiles of total vegetable consumption did not show significant associations (no data shown). sex, age, public health centre area, BMI, frequency of sports, smoking, alcohol consumption, vitamin supplement use, energy, cereals, meat, and fish by each cohort. |
24) Sato Y. (2005) | The Miyagi Cohort Study. | 47,605 subjects (22,836 men and 24,769 women) aged 40-64. | (Japan) 1990-1997 | 173 | (No data about amount of male and female cases) Colon cancer risk | Total vegetables (Green leafy vegetables, carrots and pumpkins, tomatoes, cabbage and lettuce, Chinese cabbage and tsukemono [pickles]) |
RR = 1.24 (0.79-1.95; P = 0.34) for the highest vs lowest quartile of consumption. | Amount specific data (g): ≤ 245: RR = 1. 246-277: RR = 1.10 (0.69-1.75). 278-312: RR = 1.13 (0.71-1.80). ≥ 313: RR = 1.24 (0.79-1.95).
Sex, age, smoking status, alcohol consumption, BMI, education, family history of cancer, walking time, and meat consumption. |
18) van Duijnhoven FJ (2009) | The EPIC Study | 452,755 subjects (131,985 men and 320,770 women) from 10 European countries. | 8.7-8.8 | (1992-2000 to 2006) 1,828 | Colon cancer incidence | All vegetables (leafy vegetables, fruiting vegetables, root vegetables, cabbages, onions and garlic, mushrooms, grain and pod vegetables [e.g. peas], stalk vegetables and sprouts, mixed salads/mixed vegetables, and unclassified vegetables. | excluding legumes or potatoes and other tubers)
HR = 0.85 (0.71-1.02; P = 0.11) for the highest vs lowest quintile of consumption. | Amount specific data (g/d): < 95.1: HR = 1. 95.1-141.0: HR = 0.94 (0.81-1.09). 141.0-197.5: HR = 0.97 (0.83-1.12). 197.5-284.4: HR = 0.95 (0.81-1.12). > 284.4: HR = 0.85 (0.71-1.02).
Effect modification: Tertiles of red and processed meat or alcohol did not modify the association between vegetable consumption and the risk of cancer (no data shown). BMI modified the association: an inverse association was most apparent in the highest tertile of BMI (no data shown). Stratified by age at entry, sex, and center. Adjusted for energy from fat, energy from nonfat, weight, height, physical activity, smoking status, alcohol consumption, red and processed meat consumption, fish consumption, dietary fiber from cereal sources, and consumption of fruit. |
15) Terry P (2001) | The Swedish Mammography Screening Cohort. | 61,463 women aged 40-74. | 9.6 | (1987-90 to 1998) 291 | Colon cancer risk | Vegetables (such as cabbage, tomatoes, lettuce, spinach, potatoes, and carrots and beets) |
RR = 0.90 (0.66-1.24; P = 0.43) for the highest vs lowest quartile of consumption. | Amount specific data (servings/day): < 1.0: RR = 1. 1.0-1.5: RR = 0.88 (0.64-1.21). 1.5-2.0: RR = 0.82 (0.59-1.14). > 2.0: RR = 0.90 (0.66-1.24). The relationships between fruit and vegetable consumption and colon and rectal cancer risk were similar across different strata of alcohol consumption and body mass index. Age, consumption of red meat and dairy products, and total calories. |
9) Voorrips LE. (2000) | The Netherlands Cohort Study. | 62,573 women and 58,279 men aged 55-69. | (The Netherlands) 6.3 | (1986-1992) 578 | (312 men, 266 women) Colon cancer risk | Total vegetables (Brussels sprouts, cauliflower, cabbage, spinach, cooked endive, beetroot, string beans, broad beans, kale, cooked carrots, sweet peppers, sauerkraut, rhubarb, mushrooms, gherkins, raw endive, raw carrots, lettuce, tomatoes) |
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Age, family history of colorectal cancer, and alcohol. Total energy intake, smoking, physical activity, and BMI were evaluated as potential confounders. |
8) Sellers TA (1998) | The Iowa Women's Health Study. | 35,216 women aged 55-69 years. | (USA) 10 | (1986-1995) 241 | (180 without, 61 with a family history of colon cancer) colon cancer risk | Total vegetable |
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age, total energy, and history of rectal colon polyps. |
8) Steinmetz KA. (1994) | The Iowa Women's Health Study. | 35,216 women aged 55-69. | (USA) 5 | (1986-1990) 212? | Colon cancer risk | Vegetables (alfalfa sprouts, artichokes, asparagus, avocado, bean sprouts, beets, broccoli, Brussels sprouts, cabbage/coleslaw, carrots, cauliflower, celery, chicory, corn, daikon radish, eggplant/zucchini/other summer squash, endive, escarole, garlic, green/chili peppers, iceberg/head lettuce, Jerusalem artichokes, kale/mustard/chard greens, kohlrabi, leeks, mixed vegetables, mushrooms, okra, oriental vegetables, parsley, parsnips, peapods, peas/lima beans, potatoes, radishes, rhubarb, romaine/leaf lettuce, rutabagas, scallions, spinach, string beans, tomatoes, tomato sauce, turnips, water chestnuts, yams, and yellow squash) |
RR = 0.73 (0.47-1.13) for the highest vs lowest quartile of consumption. | Amount specific data (servings/week): < 15.1: RR = 1. 15.1-21.5: RR = 0.81 (0.55-1.19). 21.6-30.4: RR = 1.17 (0.81-0.69?). > 30.4: RR = 0.73 (0.47-1.13). Age, energy. The effect of adjustment of the vegetable and fruit associations for the following factors was negligible: BMI, parity, age at first live birth, physical activity, smoking, education, history of polyps or colitis, and alcohol intake. |
7) McCullough ML (2003) | The Cancer Prevention Study II Nutrition Cohort. | 62,609 men and 70,554 women aged 50-74. (The Nutrition Cohort is a subgroup of the approx. 1.2 million participants in CPS II) | 1992-93 to 1997 | 508 (298 men, 210 women) | colon cancer risk (fatal and nonfatal) | Vegetables (defined as: beans, such as baked beans, limas, pintos, kidney, or in chili. Tomatoes, tomato juice. Broccoli. Spinach. Mustard greens, turnip greens, colards. Coleslaw, cabbage, sauerkraut. Carrots, or mixed vegetables containing carrots. Green salad. Sweet potatoes, yams. Any other vegetable, including green beans, corn, peas. Spaghetti, lasagna and other pasta with tomato sauce. Vegetable soup) |
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There was no effect modification by hormone replacement therapy (women), smoking history or multivitamin use for any main exposure and risk of colon cancer. age, exercise, METs, aspirin, smoking, family history of colorectal cancer, BMI, education, energy, multivitamin use, total calcium and red meat intake. Alcohol intake was not included because it did not influence the effect estimates when entered in the multivariate models. |
6) Michels KB. (2000) | The Nurses' Health Study | & The Health Professionals' Follow-up Study. 88,764 women aged 34-59 and 47,325 men aged 40-75. | (USA) Women: 16 | (1980-1996). Men: 10 (1986-1996) 937 (368 men, 569 women) | colon cancer risk | A vegetable was used in the definition "all vegetables" if it was included in at least 2 (out of 4) different FFQs of the NHS. | All Vegetables. (defined as: alfalfa sprouts, beets, broccoli, Brussels sprouts, cabbage, carrots, cauliflower, celery, chard greens, coleslaw, corn, eggplant, head lettuce, iceberg lettuce, kale, leaf lettuce, lima beans, mixed vegetables, mushrooms, mustard greens, peas, red chili sauce, romaine lettuce, soybeans, spinach, string beans, summer squash, sweet potatoes, tofu, tomato juice, tomato sauce, tomatoes, yams, yellow squash, winter squash, zucchini. Potatoes were not included)
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The null relation between fruit and vegetable consumption and colon cancer incidence was consistent across strata of vitamin supplement use and smoking status:
Similarly, no association was found among women or men who never smoked and never took vitamin supplements (data not shown). No effect modification was found by a family history of colorectal cancer, having had a sigmoidoscopy or colonoscopy, or having had a polyp detected (data not shown). age, family history of colorectal cancer, sigmoidoscopy, height, body mass index, pack-years of smoking, alcohol intake, physical activity, (women: menopausal status, postmenopausal hormone use,) aspirin use, vitamin supplement intake (ever use of multivitamins or vitamins A, C, or E), total caloric intake, and red meat consumption.
| 6) Giovannucci E. (1994) | The Health Professionals Follow-up Study. | 47,949 men aged 40-75. | (USA) 1986-1992 | 205 | Colon cancer risk | Vegetables (string beans, broccoli, sauerkraut, coleslaw, cauliflower, brussels sprouts, carrots, corn, peas, mixed vegetables, bean, cabbage, lentils, alfalfa sprouts, celery, mushrooms, yellow squash, eggplant, yams, spinach, iceberg or romaine lettuce, green pepper, garlic, tomatoes, tomato juice and sauce, red chili sauce, and kale or chard greens) | RR = 1.02 (0.64-1.63) for > 5 vs ≤ 2 servings/day. | Age, total energy, previous polyps, previous endoscopic screening, parental history of colorectal cancer, total pack-years of cigarette smoking, aspirin use, and intake of red meat, methionine and alcohol. |
1) Shibata A. (1992) | The Leisure World Study. | 11,580 residents of a retirement community. | (USA) 1981-1989 | 202 (97 men, 105 women) | Colon cancer risk | Vegetables (Leafy green lettuce [Romaine, Boston, bibb, butterhead, endive, escarole, salad bowl, red leafy lettuce], other leafy greens [spinach, chard, beet greens, turnip greens, mustard greens, collards, kale, dandelion greens], iceberg or head lettuce, cabbage [incude sauerkraut and coleslaw], white potatoes or turnips, sweet potatoes, yams, pumpkin [including in pie or soup], carrots, winter squash [butternut, hubbard, acorn squash [including in pie or soup], summer squash [zucchini, yellow crookneck, yellow straightneck, cocozelle, scallop squash, broccoli, tomatoes [fresh or cooked, including tomatoes in a sauce such as spaghetti or tomato soup], green peas [including snow peas and Chines pea pods], green beans or string beans, lima beans or blackeye beans, corn, asparagus, sweet green peppers, sweet red peppers, hot red chili peppers [including hot pepper sauce, chili powder, cayenne pepper, tobasco sauce, Brussels sprouts, cauliflower) |
Age and smoking. |
Adjustment for BMI or physical activity did not materially alter the results (data not shown).
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