Does Incorporating Gender Differences into Quantifying a Food Frequency Questionnaire Influence the Association of Total Energy Intake with All-Cause and Cause-Specific Mortality?

This study aims to evaluate whether incorporating gender differences in portion sizes as part of quantifying a food frequency questionnaire influences the association of total energy intake with mortality. The analysis included 156,434 participants (70,142 men and 86,292 women) in the Multiethnic Cohort Study, aged 45-75 years at baseline. A total of 49,728 deaths were identified during an average follow-up of 18.1 years. Total energy intake and percentage energy from macronutrients were calculated using original portion sizes (PSs) and gender specific (GS)-PS and were divided into quintiles for men and women. The associations of total energy intake and percentage energy from macronutrients with all-cause, cardiovascular disease (CVD), and cancer mortality were examined using Cox regression with adjustment for potential confounders. Mean ± standard deviation daily total energy intake using original-PS was 2449 ± 1135 kcal for men and 1979 ± 962 kcal for women; using GS-PS was 1996 ± 884 kcal for men and 1595 ± 731 kcal for women. For men, the hazard ratios (HRs) (95% confidence intervals) for all-cause, CVD, and cancer comparing the highest to the lowest quintile of total energy intake were 1.05 (1.00-1.10), 1.07 (0.99-1.16), 1.03 (0.95-1.13) using original-PS and 1.07 (1.02-1.12), 1.11 (1.03-1.20), 1.02 (0.94-1.12) using GS-PS, respectively. For women, the corresponding HRs were 1.03 (0.98-1.09), 0.99 (0.91-1.08), 1.10 (1.00-1.21) using original-PS and 1.06 (1.01-1.12), 1.02 (0.94-1.12), 1.07 (0.97-1.18) using GS-PS. Both versions of percentage energy from total fat were associated with an increased risk of all-cause, CVD, and cancer mortality; on the other hand, both versions of percentage energy from carbohydrate showed inverse associations with all-cause, CVD, and cancer mortality in both men and women. When using original-PS and GS-PS, the estimated total energy intake differed, resulting in marginal differences in the associations of total energy intake with all-cause, CVD, and cancer mortality.

Association of Helicobacter pylori infection and diet on the risk of gastric cancer: a case-control study in Hawaii.

OBJECTIVE: The risk factors most strongly associated with gastric cancer are the gastric bacteria Helicobacter pylori and diet. Utilizing data from a case-control study among residents in Hawaii, we examined the association of diet, presence of H. pylori, and non-cardia gastric cancer risk. METHODS: Serum taken at diagnosis for cases (n = 212) and at interview for controls (n = 336) was assayed for IgG antibodies to H. pylori group antigens and to a recombinant fragment of the cytotoxin-associated antigen A (CagA) protein, and subjects completed food frequency questionnaires. Risk measures were calculated using logistic regression. The likelihood ratio test was used to assess interactions. RESULTS: Inverse associations were found between gastric cancer risk and increasing intake of several micronutrients and vegetables among all individuals. For H. pylori/CagA-positive subjects, significant trends were present for total, green, and yellow vegetables, while a significant trend was present only for yellow vegetables among H. pylori/CagA-negative individuals. For intestinal gastric cancer, there was a suggestion that intake of vegetables, especially cruciferous vegetables, had a stronger protective effect for the H. pylori/CagA-positive group. CONCLUSIONS: Diet may play a greater role in the etiology of non-cardia gastric cancer among individuals with evidence of H. pylori infection than among those without.

A comparison of two methods of measuring food group intake: grams vs servings.

Different measurements can be used to quantify food group intake, such as servings, cups, or grams. Dietary recommendations are given in terms of servings (recently expressed as cup and ounce measurements), but research on disease risks often uses grams as the intake measure. Because serving sizes vary among foods within a food group, the method of expressing food group intake (grams vs servings) may impact disease risk analyses. Daily consumption of eight food groups was calculated as both Food Guide Pyramid servings and grams for 206,721 participants in the Multiethnic Cohort Study who completed a quantitative food frequency questionnaire between 1993 and 1996. Mean grams per serving ranged from 25 g for red meat to 172 g for dairy products. Spearman correlation coefficients between intakes as grams per day and servings per day were 0.85 for grains, 0.97 for vegetables, 0.99 for fruit, 0.95 for dairy products, 0.98 for red meat, 0.93 for processed meat, 1.00 for poultry, and 1.00 for fish. Because there was little effect on the ranking of study participants' intakes due to the method of calculating food group consumption, the two measures are interchangeable in disease risk models.

Association of dietary vitamin A, carotenoids, and other antioxidants with the risk of ovarian cancer.

UNLABELLED: Antioxidants may protect the ovaries from oxidative damage and reduce the risk of ovarian cancer. Although a few studies have examined the relation of antioxidant intake to the risk of ovarian cancer, the results have been inconclusive. Questions still remain regarding the effects of confounding factors, such as menopause, tobacco smoking, and alcohol drinking, on the association between antioxidants and ovarian cancer development. OBJECTIVE: To examine the association of the consumption of micronutrients from foods and supplements with the risk of ovarian cancer. METHODS: A structured questionnaire was administered to 558 histologically confirmed epithelial ovarian cancer cases and 607 population controls from a multiethnic, population-based case-control study conducted between 1993 and 1999 in Hawaii and Los Angeles. RESULTS: Overall, vitamin A and carotene intakes were modestly associated with a reduced risk of ovarian cancer. Inverse gradients in ovarian cancer risk with increasing dietary intake of vitamin A and beta-carotene were somewhat stronger among women with mucinous histologic types, smokers, and nondrinkers. A significant positive trend in risk associated with increasing beta-cryptoxanthin intake was observed among postmenopausal women, among women with nonmucinous tumors, and among nonsmokers. The intake of other carotenoids and antioxidants, either from foods or supplements, was unrelated to ovarian cancer risk. CONCLUSION: Our findings suggest that dietary vitamin A and beta-carotene are modestly protective against ovarian cancer, particularly among smokers. Our data suggest a role for retinoic acid signaling pathways in ovarian carcinogenesis.

Breast cancer in a multiethnic cohort in Hawaii and Los Angeles: risk factor-adjusted incidence in Japanese equals and in Hawaiians exceeds that in whites.

Few data exist on the extent to which the differences in breast cancer risk between "racial-ethnic" groups in the United States (US) are "explained" by differences in their distribution of risk factors. We have determined this for African-American (AA), native Hawaiian (NH), Japanese-American (JA), Latina-US-born (L-US), Latina-non-US-born (L-NUS), and white (W) women using prospective incidence data on 88,712 postmenopausal women recruited in 1993-1996. We identified 1,757 incident breast cancer cases through 1999 among these women (1,116 cases after excluding women with a simple hysterectomy or missing risk factor data). Data were available on seven "known" risk factors: ages at menarche and first birth; parity; age at and type of menopause; weight; hormone replacement therapy use; and alcohol consumption. The relative risks (RRs) of breast cancer (with the RR in Ws set to 1.0) for the groups were as follows: W = 1.0; AA = 0.78; NH = 1.33; JA = 0.99; L-US = 0.77; and L-NUS = 0.60. After adjustment for the risk factors, the RRs were as follows: W = 1.0; AA = 0.98; NH = 1.65; JA = 1.11; L-US = 0.95; and L-NUSB = 0.84. The slightly greater risk of the JAs compared with the Ws is in sharp contrast to the very low breast cancer rates that were observed in "traditional" Japanese women and in early Japanese migrants. The adjusted RR of NHs is 65% greater than that of Ws, and that of migrant Latinas is 16% lower than that of Ws. Elucidating the causes of the high rates in NHs is now a major focus of our efforts.

Adherence to the Food Guide Pyramid recommendations among Japanese Americans, Native Hawaiians, and whites: results from the Multiethnic Cohort Study.

The Food Guide Pyramid is designed to help Americans make healthful food choices. Whereas national data have been collected to examine adherence to the pyramid recommendations in whites, African-Americans, and Latinos, there are virtually no data available for Japanese Americans or Native Hawaiians. Here we present data on intakes of the Food Guide Pyramid food groups (as servings per day) as well as of the components of the pyramid tip (discretionary fat, added sugar, and alcohol) in these ethnic groups and examine adherence to each of the food group recommendations. Degree of adherence to the fruit group recommendation was similar among the ethnic groups and energy-intake categories, but adherence to the other recommendations was greatest for those consuming more than 2,800 kilocalories per day. However, subjects in this energy-intake group also consumed more than three times as much discretionary fat, added sugar, and alcohol.

Adherence to the food guide pyramid recommendations among African Americans and Latinos: results from the Multiethnic Cohort.

The objective of the study was to determine the degree of adherence to the Food Guide Pyramid recommendations among African Americans, Latinos born in the United States, and Latinos born in Mexico. Subjects were from the Multiethnic Cohort Study in Hawaii and Los Angeles, and completed a self-administered quantitative food frequency questionnaire at baseline in 1993-1996. Dairy recommendations were the least likely of all the food group recommendations to be followed, with 61% to 99% of individuals in the three ethnic groups not consuming the recommended number of servings. African Americans were less likely to adhere to all of the food group recommendations compared to the two Latino groups. A greater percentage of Latinos born in the United States did not adhere to the food group recommendations compared to Latinos born in Mexico. All three groups would benefit from interventions designed to promote healthy food choices.

Well-done red meat, metabolic phenotypes and colorectal cancer in Hawaii.

Heterocyclic amines (HAAs) and polycyclic hydrocarbons are suspected colorectal cancer (CRC) carcinogens that are found in well-done meat. They require metabolic activation by phase I enzymes, such as the smoking-inducible CYP1A isoenzymes. N-acetyltransferase 2 (NAT2) also play a role in the further activation of HAAs. We conducted a population-based case-control study in Hawaii to test the associations of preference for well-done red meat and HAA intake with colon and rectal cancers, as well as the modifying effects of NAT2 and CYP1A2. We interviewed 727 Japanese, Caucasian or Native Hawaiian cases and 727 controls matched on sex, age, and ethnicity. HAA intake was estimated based on consumption of meat and fish for each of several cooking methods and doneness levels. A subgroup of 349 cases and 467 controls was phenotyped for CYP1A2 by a caffeine test. We found that preference for well-done red meat was associated with a 8.8-fold increased risk of CRC (95% CI: 1.7-44.9) among ever-smokers with the NAT2 and CYP1A2 rapid phenotypes, compared to ever-smokers with low NAT2 and CYP1A2 activities and who preferred their red meat rare or medium. A dose-dependent association was also found between the HAA intake estimates and male rectal cancer, with a two- to three-fold increase in risk from the low (T(1)) to high (T(3)) tertile of intake for each HAA. This association was strongest for MeIQx. HAA intake was not associated with male colon cancer or colon or rectal cancer in women. These data provide support to the hypothesis that exposure to pyrolysis products through consumption of well-done meat increases the risk of CRC, particularly in individuals who smoke and are genetically susceptible (as determined by a rapid phenotype for both NAT2 and CYP1A2). An attempt to examine the risk associated with specific HAAs suggested that the main HAAs increase risk of rectal cancer in men and that they do not appreciably affect risk of rectal cancer in women or of colon cancer in either sex.

Association of vegetable, fruit, and grain intakes with colorectal cancer: the Multiethnic Cohort Study.

BACKGROUND: It is uncertain whether or not vegetables, fruit, or grains protect against colorectal cancer. OBJECTIVE: In a large prospective study, we investigated the association of vegetable, fruit, and grain intakes with colorectal cancer risk. DESIGN: Between 1993 and 1996, 85 903 men and 105 108 women completed a quantitative food-frequency questionnaire that included approximately 180 foods and beverages in the Multiethnic Cohort Study. A diagnosis of colorectal cancer was made in 1138 men and 972 women after an average follow-up of 7.3 y. Cox proportional hazards models were used to calculate multivariate-adjusted relative risks and 95% CIs for colorectal cancer. RESULTS: In men, multivariate adjustment for energy intake, dietary, and nondietary variables resulted in relative risks in the highest quintile group of 0.74 (95% CI: 0.59, 0.93; P for trend = 0.02) for vegetables and fruit combined, 0.80 (95% CI: 0.64, 0.99; P for trend = 0.09) for fruit alone, and 0.85 (95% CI: 0.69, 1.05; P for trend = 0.05) for vegetables alone. When colon and rectal cases were separated among men, the inverse associations were stronger for colon than for rectal cancer. In women, none of the associations with vegetables, fruit, or vegetables and fruit combined were significant. Grain intake was not associated with colorectal cancer for either men or women. CONCLUSION: The intake of vegetables and fruit was inversely related to colorectal cancer risk among men but not among women. The association appears stronger for colon than for rectal cancer.

Body mass index and physical activity as risk factors for pancreatic cancer: the Multiethnic Cohort Study.

OBJECTIVE: To examine body mass index (BMI) and physical activity as risk factors for pancreatic cancer. METHODS: Eight-year prospective data from 77,255 men and 90,175 women including 237 and 235 pancreatic cancer cases, respectively, in the Hawaii-Los Angeles Multiethnic Cohort Study were analyzed. Participants completed a questionnaire that included questions on body weight, height, and physical activity. Cox proportional hazards models were calculated to estimate relative risks (RR) of pancreatic cancer by levels of BMI and total physical activity (as metabolic equivalents (METs)) adjusted for several potential confounders. RESULTS: Obesity (BMI > or = 30 kg/m(2)) was associated with an increased pancreatic cancer risk in men (RR = 1.51 (95% CI: 1.02-2.26)), but a reduced risk in women (RR = 0.65 (95% CI: 0.43-0.99)). In men the risk was higher in never smokers than in current or former smokers, though differences were not statistically significant. Physical activity was not associated with pancreatic cancer risk in either men or women. CONCLUSION: The findings suggest, that a BMI of > or = 30 kg/m(2) may be a risk factor for pancreatic cancer in men. No evidence of an effect of physical activity on risk was found.

Vegetable intake and pancreatic cancer risk: the multiethnic cohort study.

Investigators studying associations between vegetable intake and pancreatic cancer risk have reported inconsistent findings to date. To further explore these associations, the authors analyzed data on 183,522 participants enrolled in the Hawaii-Los Angeles Multiethnic Cohort Study in 1993-1996. Intakes of total vegetables, light green, dark green, yellow-orange, and cruciferous vegetables, tomato products, and legumes were estimated from a quantitative food frequency questionnaire. After an average of 8.3 years of follow-up, 529 pancreatic cancer cases were identified. Multivariate-adjusted Cox proportional hazards models were created. All statistical tests were two-sided. Overall, total vegetable intake was not associated with pancreatic cancer risk, nor was intake of vegetable subgroups. Current smokers, who were at increased risk of pancreatic cancer (relative risk = 1.78, 95% confidence interval: 1.40, 2.27), had a decreased risk with higher intake of dark green vegetables (for comparison of extreme quartiles, relative risk = 0.50, 95% confidence interval: 0.27, 0.92; p-trend = 0.029). The inverse association for dark green vegetables was also seen in African Americans (p-trend = 0.043). In stratified analyses, inverse associations with total vegetables, light green vegetables, and legumes were significant in overweight/obese subjects. In conclusion, the authors found no evidence for an inverse association between vegetable intake and pancreatic cancer overall, but inverse associations in high-risk persons suggest the need for further investigation.

Separate estimates of portion size were not essential for energy and nutrient estimation: results from the Southern Community Cohort food-frequency questionnaire pilot study.

OBJECTIVE: A food-frequency questionnaire (FFQ) was developed to assess habitual dietary intake in the Southern Community Cohort Study (SCCS), a prospective epidemiological study to analyse disparities in cancer and other chronic diseases between African-Americans and Whites. DESIGN: Frequency and portion size estimates were obtained for each of 104 foods. Daily intakes of 13 food groups, energy and 18 nutrients were computed. Each participant's rank and quintile classification of nutrient intakes was determined with and without the use of the subject's reported portion size. SUBJECTS: The sample was obtained from the SCCS pilot study conducted in Tennessee, Mississippi and Florida, and consisted of 209 adults, 54% African-American, with a mean (standard deviation) age of 57.1 (12.5) years. RESULTS: Correlations between the ranks from the two methods of estimation were high, ranging from 0.66 to 0.94 for food groups and 0.81 to 0.94 for nutrients. Pearson correlations were similarly high for food groups and nutrients. Concordance in exact quintile rank across the nutrient indices ranged from 52 to 70%, rising to 90-99% for concordance within adjacent quintiles. CONCLUSIONS: To reduce the respondents' burden and to increase data completeness, the assignment of a uniform portion size when scoring the SCCS FFQ was considered acceptable.

Dietary fiber and colorectal cancer risk: the multiethnic cohort study.

OBJECTIVE: To investigate the association of dietary fiber with colorectal cancer METHODS: A total of 85,903 men and 105,108 women completed a quantitative food frequency questionnaire in 1993-1996. A total of 1,138 men and 972 women were subsequently diagnosed with adenocarcinoma of the large bowel. Cox proportional hazards models were used to calculate multivariate adjusted relative risks (RR) and 95% confidence intervals (95% CI) for colorectal cancer. RESULTS: High consumers of dietary fiber were more active, less overweight, and less likely to be cigarette smokers than low consumers in both sexes. Fiber was inversely associated with colorectal cancer risk after adjustment for age and ethnicity in men (RR = 0.49; 95% CI, 0.41-0.60, highest vs. lowest quintile) and women (RR = 0.75; 95% CI, 0.61-0.92). After further adjustment for lifestyle and dietary factors, the inverse association remained significant in men (RR = 0.62; 95% CI, 0.48-0.79), but not in women (RR = 0.88; 95% CI, 0.67-1.14). Adjustment for the combination of replacement hormone use with either cigarette smoking or body mass index accounted for the lack of association with fiber in women. CONCLUSION: Dietary fiber was inversely associated with colorectal cancer risk in men, but its relation to replacement hormone use and other factors affected its inverse association in women.

Dietary energy density is associated with overweight status among 5 ethnic groups in the multiethnic cohort study.

Differences in BMI among ethnic groups may be partially explained by the consumption of energy-dense foods, which influences energy intake in controlled laboratory studies. However, the role of dietary energy density (ED, kJ/g) in free-living persons is less understood. Our objective was to determine whether ED is related to current BMI and the risk for overweight and obesity and whether these relations are consistent among ethnic groups. We calculated ED from responses to a quantitative food frequency questionnaire and validated the measures against multiple 24-h recalls. Subjects consisted of 191,023 participants in the Hawaii-Los Angeles Multiethnic Cohort who were African American, Native Hawaiian, Japanese American, Latino, or Caucasian. Mean ED varied from a low of 4.62 kJ/g in Japanese American men to a high of 5.08 kJ/g in African American men. Mean BMI was lowest in Japanese Americans of both sexes and highest in Native Hawaiian men and African American women. After adjusting for the amount of food consumed per day, age, current smoking status, physical activity, chronic disease, and education, a 1 kJ/g increase in ED was associated with an increase in BMI of approximately 1 kg/m2 in each ethnic sex group. This same increase in ED was associated with a significantly increased risk of being overweight in all ethnic sex groups, varying from 4% in African American men to 34% in Japanese American women. Our findings suggest that consumption of an energy dense diet is a risk factor for higher BMI in both men and women across ethnic groups.

Sun exposure, diet, and melanoma in Hawaii Caucasians.

Much uncertainty remains about the type of sunlight exposure that most increases risk of cutaneous melanoma and the role of diet. The authors conducted a population-based case-control study (1986-1992) of Caucasians living on Oahu, Hawaii; included were 278 cases and age- and sex-matched controls. Plasma samples were measured for retinol, carotenoids, and alpha-tocopherol by high-pressure liquid chromatography. Selenium was measured in blood and toenails by neutron activation. Celtic and English ancestries, migration to Hawaii before age 20 years, fair complexion, inability to tan, and family history of skin cancer, as well as height, hours spent in the summer sun, blistering sunburns during adolescence, and moles, all increased melanoma risk. With regard to diet and biomarkers, only alcohol was associated with risk. The odds ratios for increasing tertiles of lifetime ethanol intake were 1.0, 1.2 (95% confidence interval (CI): 0.6, 2.2), and 2.3 (95% CI: 1.2, 4.4) (p for trend = 0.01) for men and 1.0, 1.1 (95% CI: 0.5, 2.4), and 1.7 (95% CI: 0.7, 3.8) (p for trend = 0.19) for women. Dietary lipids were unrelated to risk, but polyunsaturated fat intake appeared to modify the effects of alcohol and toenail selenium on melanoma risk. These data provide additional evidence for the association of constitutional susceptibility factors, intense sun exposure (particularly before age 20 years), and alcohol consumption with melanoma risk.

Prostate cancer incidence and intake of fruits, vegetables and related micronutrients: the multiethnic cohort study* (United States).

OBJECTIVE: To describe the relationship between the intake of fruits, vegetables, and related vitamins and antioxidants, and the risk of prostate cancer in male participants in a large multiethnic cohort study. METHODS: Food and nutrient intakes in 1993-1996 were calculated from a detailed food frequency questionnaire (FFQ) designed to account for the food and nutrient intake of the ethnic groups represented in the study (82,486 African-American, Japanese-American, Native-Hawaiian, Latino and White males included here). Follow-up for incident cancers utilized local SEER registries. Vital status was ascertained using state death files. Data on PSA utilization from a later questionnaire was also examined. RESULTS: A total of 3,922 incident cancer cases were ascertained during follow-up. Modestly increased risks of prostate cancer were observed in relation to higher intakes of several food items including light green lettuce and dark leafy green vegetables. Notably, no significant protective associations of any foods were seen, including tomato intake; and intakes of two complex foods containing tomato sauce (pizza and Spanish rice) were associated with modest increases in risk. PSA test use was significantly and positively related to intake of some of these same items, implying a degree of disease detection-bias. Analysis of non-localized and high grade disease (1,345 cases) showed no significant protective associations with overall fruits and vegetables intake, related micronutrients, or with intake of selected complex food items. CONCLUSIONS: We found no statistically significant evidence of a protective effect against prostate cancer of higher levels of intake of any of these foods, associated micronutrients or supplements. A possible explanation for the positive associations with risk of several of the foods normally considered to be healthy is detection bias, since "healthy" dietary intake was related to greater use of the PSA test.

Meat and fat intake as risk factors for pancreatic cancer: the multiethnic cohort study.

BACKGROUND: Meat intake has been associated with risk of exocrine pancreatic cancer, but previous findings have been inconsistent. This association has been attributed to both the fat and cholesterol content of meats and to food preparation methods. We analyzed data from the prospective Multiethnic Cohort Study to investigate associations between intake of meat, other animal products, fat, and cholesterol and pancreatic cancer risk. METHODS: During 7 years of follow-up, 482 incident pancreatic cancers occurred in 190,545 cohort members. Dietary intake was assessed using a quantitative food frequency questionnaire. Associations for foods and nutrients relative to total energy intake were determined by Cox proportional hazards models stratified by gender and time on study and adjusted for age, smoking status, history of diabetes mellitus and familial pancreatic cancer, ethnicity, and energy intake. Statistical tests were two-sided. RESULTS: The strongest association was with processed meat; those in the fifth quintile of daily intake (g/1000 kcal) had a 68% increased risk compared with those in the lowest quintile (relative risk = 1.68, 95% confidence interval = 1.35 to 2.07; Ptrend < .01). The age-adjusted yearly incidence rates per 100,000 persons for the respective quintiles were 41.3 and 20.2. Intakes of pork and of total red meat were both associated with 50% increases in risk, comparing the highest with the lowest quintiles (both Ptrend < .01). There were no associations of pancreatic cancer risk with intake of poultry, fish, dairy products, eggs, total fat, saturated fat, or cholesterol. Intake of total and saturated fat from meat was associated with statistically significant increases in pancreatic cancer risk but that from dairy products was not. CONCLUSION: Red and processed meat intakes were associated with an increased risk of pancreatic cancer. Fat and saturated fat are not likely to contribute to the underlying carcinogenic mechanism because the findings for fat from meat and dairy products differed. Carcinogenic substances related to meat preparation methods might be responsible for the positive association.

Dietary patterns using the Food Guide Pyramid groups are associated with sociodemographic and lifestyle factors: the multiethnic cohort study.

Dietary patterns have been used to identify typical combinations of foods that may be associated with disease risks. We defined dietary patterns among 195,298 participants of the Multiethnic Cohort Study in Hawaii and Los Angeles in 1993-1996. Intakes of Food Guide Pyramid groups were calculated from a quantitative FFQ for subjects of 5 ethnic groups (African Americans, Hawaiians, Japanese Americans, Latinos, and whites). Three distinct dietary patterns, "Fat and Meat," "Vegetables," and "Fruit and Milk," were identified by exploratory factor analysis with a varimax rotation and validated by confirmatory factor analysis. Similar factor loadings were found for each of 10 ethnic-gender groups in stratified analyses. The odds ratios (OR) for being above the median scores for each factor were calculated. Age, gender, and ethnicity had relatively strong associations with dietary patterns whereas education showed only weak associations. BMI > or = 30 was strongly positively associated with the Fat and Meat pattern (OR = 2.14, 95% CI: 2.08-2.20, vs. BMI < 25). Current smokers showed a positive association with the Fat and Meat pattern (OR = 1.67, CI: 1.62-1.72, vs. nonsmokers) and inverse associations with the Vegetables (OR = 0.66, CI: 0.64-0.68) and Fruit and Milk patterns (OR = 0.53, CI: 0.52-0.55). Physical activity was positively associated with the Vegetables and Fruit and Milk patterns but not with the Fat and Meat pattern. These findings support the hypothesis that dietary patterns are influenced by interrelated sociocultural, demographic, and other lifestyle factors and may be useful in investigations of diet-disease relations.

B-vitamin intake, metabolic genes, and colorectal cancer risk (United States).

OBJECTIVE: This population-based case-control study was designed to investigate the interrelationships between polymorphisms in the methylenetetrahydrofolate (MTHFR C677T and A1298C) gene and other genes (MTR A2756G; MTRR A66G and CBS 844ins68), intake of B-vitamins and colorectal cancer risk (CRC). METHODS: We interviewed 727 CRC cases of Japanese, Caucasian, or Native Hawaiian origin and 727 controls matched on sex, age, and ethnicity. RESULTS: Compared to the homozygous wild-type genotype, the odds ratios for subjects with one or two MTHFR 677T variant alleles were 0.8 (0.6-1.1) and 0.7 (0.5-1.1), respectively (p for gene-dosage effect: 0.04). The TT genotype was associated with a 50-60% decrease in CRC risk among subjects with high intake of folate or vitamin B6, compared to those with the CC genotype and low levels of intake. The MTHFR 1298C and CBS8 44ins68 variant alleles were also found to be weakly protective against CRC and to act jointly with the 677T allele. CONCLUSIONS: This study provides additional evidence for a decreased CRC risk for subjects with the MTHFR 677T allele, particularly at high levels of folate and vitamin B6 intake. Our data also suggest that the relationships between CRC and the MTHFR A1298C and CBS 844ins68 polymorphisms warrant further study.