Quintile Of Whole Grain Intake Research Articles

Higher intake of whole grains and dietary fiber are associated with lower risk of liver cancer and chronic liver disease mortality

The relationship between dietary factors and liver disease remains poorly understood. This study evaluated the associations of whole grain and dietary fiber intake with liver cancer risk and chronic liver disease mortality. The National Institutes of Health–American Association of Retired Persons Diet and Health Study cohort recruited 485, 717 retired U.S. participants in 1995–1996. Follow-up through 2011 identified 940 incident liver cancer cases and 993 deaths from chronic liver disease. Compared with the lowest, the highest quintile of whole grain intake was associated with lower liver cancer risk (Hazard ratio [HR]Q5 vs. Q1 = 0.78, 95% confidence interval [CI]: 0.63–0.96) and chronic liver disease mortality (HRQ5 vs. Q1 = 0.44, 95% CI: 0.35–0.55) in multivariable Cox models. Dietary fiber was also associated with lower liver cancer risk (HRQ5 vs. Q1 = 0.69, 95% CI: 0.53–0.90) and chronic liver disease mortality (HRQ5 vs. Q1 = 0.37, 95% CI: 0.29–0.48). Fiber from vegetables, beans and grains showed potential protective effect. Here, we show that higher intake of whole grain and dietary fiber are associated with lower risk of liver cancer and liver disease mortality.

Association between grains, gluten and the risk of colorectal cancer in the Cancer Prevention Study-II Nutrition Cohort.

Evidence supports a role of whole grains in colorectal cancer (CRC) prevention, but the association between gluten intake and CRC risk in healthy populations is unclear. We examined the association of grain and gluten intake with risk of CRC overall and by subsite among Cancer Prevention Study-II Nutrition Cohort participants. In 1999, 50,118 men and 62,031 women completed food frequency questionnaires assessing grain intake. Gluten intake was estimated using the protein content of grain products. Multivariable-adjusted hazards ratio (HR) and 95% confidence interval (CI) of CRC risk were estimated using Cox proportional hazards regression. During follow-up through 2013, 1742 verified CRC cases occurred. For the highest vs. lowest quintiles of whole grain intake, HRs (95% CIs) of CRC risk were 0.77 (0.61-0.97; P trend = 0.03) among men and 1.10 (95% CI 0.88-1.36; P trend = 0.14) among women (P interaction by sex = 0.01). Men in the highest vs. lowest quintile of whole grain intake had a 43% lower risk of rectal cancer (HR = 0.57, 95% CI 0.35-0.93, P trend = 0.04). Gluten intake was not associated with CRC risk overall (HR = 1.10, 95% CI 0.93-1.32, P trend = 0.10), but was associated with risk of proximal colon cancer among men and women, combined (HR = 1.37, 95% CI 1.07-1.75, quintile 5 vs. 1, P trend = 0.001) and separately. Refined grains and grain-based sweets were not associated with CRC risk. We found that higher whole grain intake was associated with lower CRC risk among older US men, but not women. The positive association of gluten intake with the risk of proximal colon cancer deserves further study.

Abstract 18: Whole Grain Intake and Risk of All-Cause and Cause-Specific Mortality in US Men and Women

Background: Whole grains are rich in fiber, vitamins, minerals, and antioxidants that have favorable effects on health through multiple pathways. Although epidemiologic studies have suggested that whole grain intake may reduce risk of type 2 diabetes, hypertension and cardiovascular disease (CVD), limited evidence exists regarding whole grains’ associations with mortality in prospective studies. Methods: Whole grain consumption was measured using a validated food frequency questionnaire every 2-4 years among 74,341 women in the Nurses’ Health Study (1984-2010) and 43,990 men in the Health Professionals Follow-Up Study (1986-2010) who were free of CVD, diabetes, and cancers at baseline. Intake of whole grain foods including brown rice, dark breads, whole-grain ready-to-eat cereals, cooked cereal, popcorn, wheat germ, bran and other grains. We used the cumulative average of whole grain intake from all available dietary questionnaires from baseline through the end of follow-up were used to better represent long-term or habitual intake, and to minimize within-person variation. Cox regression models were used to evaluate the associations between whole grain intake and mortality. Results: We documented 26,918 deaths in these two cohorts during 2,731,264 person-years of follow-up through 2010. After multivariate adjustment for potential confounders, including age, smoking, BMI, physical activity, and alternate healthy eating index, the hazard ratios (HRs) of total mortality comparing the highest with the lowest quintile of whole grain intake was 0.89 (95% confidence interval [CI] 0.84, 0.94, P for trend < 0.0001) in NHS and 0.92 (95%CI 0.87, 0.98, P for trend = 0.01) in HPFS; and the pooled HR was 0.91 (95% CI 0.85, 0.95). An inverse association was observed for CVD mortality: the pooled HRs (95% CIs) comparing extreme quintiles were 0.85 (95%CI 0.78, 0.92, P for trend < 0.0001). Whole grain intake was not significantly associated with cancer mortality, the pooled HR was 0.98 (95% CI 0.91, 1.04, P for trend = 0.49). In addition, total bran intake was observed to be significantly inversely associated with CVD mortality, with pooled HR 0.80 (95% CI 0.73, 0.87, P for trend < 0.0001), while total germ intake was not associated with risk of mortality after adjustment for bran intake. These associations did not change materially among men and women who had a healthful lifestyle or diet. In sensitivity analysis, to minimize reverse causation, we used a 4-year lagged analysis or further stopped updating diet after participants reported occurrence of hypertension and high cholesterol, and all these sensitivity analysis indicated the robustness of our results. Conclusions: Our data support the hypothesis that higher whole grain consumption may have beneficial effects on lowering total and CVD mortality in US men and women.

Whole grain intake, incident hip fracture and presumed frailty in the Iowa Women's Health Study

Whole cereal grain foods are rich in phytate, a Ca chelator, and could increase the risk of hip fracture. The objective of the present study was to investigate the association between baseline whole grain intake and incident hip fracture. In the present study, 29 192 women who at baseline in 1986 were aged 55-69 years, free of diabetes, and reported a plausible energy intake of 2508-20 900 kJ/d and reported no fracture since the age of 35 years were followed. Hip fracture (n 746) was self-reported in five questionnaires through 2004. Of 1451 hip fractures identified passively by Medicare linkage through 31 December 2004 (Medicare hip fracture), 507 had also been self-reported. Whole grain intake was inversely related to Medicare hip fracture (P trend = 0.02), but it was unrelated to self-reported hip fracture (P trend = 0.27). The hazard ratio in the highest to lowest quintile of whole grain intake for incident Medicare-only hip fracture (n 944) was 0.66 (95% CI 0.53, 0.82) after adjustment for age, energy intake, education, BMI, waist-to-hip ratio, farm residence, physical activity, oestrogen use, smoking, alcohol use, history of cancer and other dietary variables. Medicare-only cases may have failed to self-report due to severe illness; hazard ratio for total mortality after hip fracture was 2.92 (2.37, 3.59) for Medicare-only cases v. Medicare-confirmed self-reported cases. In conclusion, in this cohort, the inverse association between whole grain intake and hip fracture was explained by ascertainment bias. Whole grain intake may increase the ability to respond to a questionnaire and self-report hip fracture, and could reflect less undocumented frailty.

Whole grain intake and its cross-sectional association with obesity, insulin resistance, inflammation, diabetes and subclinical CVD: The MESA Study

We examined the relationship between whole grain intake and obesity, insulin resistance, inflammation, diabetes and subclinical CVD using baseline data from the Multi-Ethnic Study of Atherosclerosis. Whole grain intake was measured by a 127-item FFQ in 5496 men and women free of CHD and previously known diabetes. Mean whole grain intake was 0.5 (sd 0.5) servings per d; biochemical measures reflect fasting levels. After adjustment for demographic and health behaviour variables, mean differences for the highest quintile of whole grain intake minus the lowest quintile of intake were 0.6 kg/m2 for BMI, 0.36 mg/l for C-reactive protein, 0.82 micromol/l for homocysteine, 0.15 mU/l*mmol/l for homeostasis model assessment (HOMA), 0.48 mU/l for serum insulin, 2.0 mg/dl for glucose and 5.7 % for prevalence of newly diagnosed impaired fasting glucose (glucose >or= 100 mg/dl or diabetes medication). These differences represent 11-13 % of a standard deviation of BMI, HOMA, glucose and impaired fasting glucose, but 23 %, 52 % and 80 % of a standard deviation of homocysteine, C-reactive protein and insulin, respectively. An inverse association between whole grains and urine albumin excretion was suggested but retained statistical significance after adjustment only in Chinese and Hispanic participants. No associations were observed between whole grain intake and two subclinical disease measures: carotid intima-media thickness and coronary artery calcification. Concordant with previous research, whole grain intake was inversely associated with obesity, insulin resistance, inflammation and elevated fasting glucose or newly diagnosed diabetes. Counter to hypothesis, however, whole grain intake was unrelated to subclinical CVD.

Whole grain, bran, and germ intake and risk of type 2 diabetes: a prospective cohort study and systematic review.

BackgroundControl of body weight by balancing energy intake and energy expenditure is of major importance for the prevention of type 2 diabetes, but the role of specific dietary factors in the etiology of type 2 diabetes is less well established. We evaluated intakes of whole grain, bran, and germ in relation to risk of type 2 diabetes in prospective cohort studies.Methods and FindingsWe followed 161,737 US women of the Nurses' Health Studies (NHSs) I and II, without history of diabetes, cardiovascular disease, or cancer at baseline. The age at baseline was 37–65 y for NHSI and 26–46 y for NHSII. Dietary intakes and potential confounders were assessed with regularly administered questionnaires. We documented 6,486 cases of type 2 diabetes during 12–18 y of follow-up. Other prospective cohort studies on whole grain intake and risk of type 2 diabetes were identified in searches of MEDLINE and EMBASE up to January 2007, and data were independently extracted by two reviewers. The median whole grain intake in the lowest and highest quintile of intake was, respectively, 3.7 and 31.2 g/d for NHSI and 6.2 and 39.9 g/d for NHSII. After adjustment for potential confounders, the relative risks (RRs) for the highest as compared with the lowest quintile of whole grain intake was 0.63 (95% confidence interval [CI] 0.57–0.69) for NHSI and 0.68 (95% CI 0.57–0.81) for NHSII (both: p-value, test for trend <0.001). After further adjustment for body mass index (BMI), these RRs were 0.75 (95% CI 0.68–0.83; p-value, test for trend <0.001) and 0.86 (95% CI 0.72–1.02; p-value, test for trend 0.03) respectively. Associations for bran intake were similar to those for total whole grain intake, whereas no significant association was observed for germ intake after adjustment for bran. Based on pooled data for six cohort studies including 286,125 participants and 10,944 cases of type 2 diabetes, a two-serving-per-day increment in whole grain consumption was associated with a 21% (95% CI 13%–28%) decrease in risk of type 2 diabetes after adjustment for potential confounders and BMI.ConclusionsWhole grain intake is inversely associated with risk of type 2 diabetes, and this association is stronger for bran than for germ. Findings from prospective cohort studies consistently support increasing whole grain consumption for the prevention of type 2 diabetes.

Whole Grain Intake and Incident Endometrial Cancer: The Iowa Women's Health Study

We examined whether there is an association between whole grain intake and incident endometrial cancer and whether the association varied by use of hormone replacement therapy. The study included 23,014 Iowa women, aged 55-69 years in 1986. A mailed food frequency questionnaire was used to estimate grain intake, hormone replacement therapy use, and other cancer risk factors. Cancer incidence from 1986 to 1998 was also collected. In analyses stratified by hormone replacement therapy use, an inverse association between whole grain intake and endometrial cancer was observed among never-users of hormone replacement therapy (p for trend = 0.05). Never-users in the highest quintile of whole grain intake were 0.63 times as likely to develop endometrial cancer as those in the lowest quintile of whole grain intake (95% confidence interval = 0.39-1.01). Among hormone replacement therapy users, no association between whole grain intake and endometrial cancer was evident. There was no statistically significant association between whole grain intake and incident endometrial cancer when users of hormone replacement therapy and nonusers were analyzed together. There also was no association between refined grain intake and endometrial cancer. Whole grain intake may protect against endometrial cancer among never-users of hormone replacement therapy.

Whole Grain Consumption and Risk of Ischemic Stroke in Women

Although increased intake of grain products has been recommended to prevent cardiovascular disease (CVD), prospective data examining the relation of whole grain intake to risk of ischemic stroke are sparse, especially among women. To examine the hypothesis that higher whole grain intake reduces the risk of ischemic stroke in women. A prospective cohort of 75,521 US women aged 38 to 63 years without previous diagnosis of diabetes mellitus, coronary heart disease, stroke, or other CVDs in 1984, who completed detailed food frequency questionnaires (FFQs) in 1984, 1986, 1990, and 1994, and were followed up for 12 years as part of the Nurses' Health Study. Incidence of ischemic stroke, confirmed by medical records, by quintile of whole grain intake according to FFQ responses. During 861,900 person-years of follow-up, 352 confirmed incident cases of ischemic stroke occurred. We observed an inverse association between whole grain intake and ischemic stroke risk. The age-adjusted relative risks (RRs) from the lowest to highest quintiles of whole grain intake were 1.00 (referent), 0.68 (95% confidence interval [CI], 0.49-0.94), 0.69 (95% CI, 0.51-0.95), 0.49 (95% CI, 0.35-0.69), and 0.57 (95% CI, 0.42-0.78; P =.003 for trend). Adjustment for smoking modestly attenuated this association (RR comparing extreme quintiles, 0.64; 95% CI, 0.47-0.89). This inverse association remained essentially unchanged with further adjustment for known CVD risk factors, including saturated fat and transfatty acid intake (multivariate-adjusted RR comparing extreme quintiles, 0.69; 95% CI, 0.50-0.98). The inverse relation between whole grain intake and risk of ischemic stroke was also consistently observed among subgroups of women who never smoked, did not drink alcohol, did not exercise regularly, or who did not use postmenopausal hormones. No significant association was observed between total grain intake and risk of ischemic stroke. In this cohort, higher intake of whole grain foods was associated with a lower risk of ischemic stroke among women, independent of known CVD risk factors. These prospective data support the notion that higher intake of whole grains may reduce the risk of ischemic stroke.

Carbohydrates, dietary fiber, and incident type 2 diabetes in older women

Dietary carbohydrates may influence the development of type 2 (non-insulin-dependent) diabetes, for example, through effects on blood glucose and insulin concentrations. We examined the relations of baseline intake of carbohydrates, dietary fiber, dietary magnesium, and carbohydrate-rich foods and the glycemic index with incidence of diabetes. This was a prospective cohort study of 35988 older Iowa women initially free of diabetes. During 6 y of follow-up, 1141 incident cases of diabetes were reported. Total grain, whole-grain, total dietary fiber, cereal fiber, and dietary magnesium intakes showed strong inverse associations with incidence of diabetes after adjustment for potential nondietary confounding variables. Multivariate-adjusted relative risks of diabetes were 1.0, 0.99, 0.98, 0.92, and 0.79 (P for trend: 0.0089) across quintiles of whole-grain intake; 1.0, 1.09, 1.00, 0.94, and 0.78 (P for trend: 0.005) across quintiles of total dietary fiber intake; and 1.0, 0.81, 0.82, 0.81, and 0.67 (P for trend: 0.0003) across quintiles of dietary magnesium intake. Intakes of total carbohydrates, refined grains, fruit and vegetables, and soluble fiber and the glycemic index were unrelated to diabetes risk. These data support a protective role for grains (particularly whole grains), cereal fiber, and dietary magnesium in the development of diabetes in older women.