Non-whole Grain Research Articles

Dietary patterns, food groups, and rectal cancer risk in Whites and African-Americans.

Associations between individual foods and nutrients and colorectal cancer have been inconsistent, and few studies have examined associations between food, nutrients, dietary patterns, and rectal cancer. We examined the relationship between food groups and dietary patterns and risk for rectal cancer in non-Hispanic Whites and African-Americans. Data were from the North Carolina Colon Cancer Study-Phase II and included 1,520 Whites (720 cases, 800 controls) and 384 African-Americans (225 cases, 159 controls). Diet was assessed using the Diet History Questionnaire. Multivariate logistic regression models were used to estimate odds ratios and 95% confidence intervals. Among Whites, non-whole grains and white potatoes were associated with elevated risk for rectal cancer whereas fruit, vegetables, dairy, fish, and poultry were associated with reduced risk. In African-Americans, high consumption of other fruit and added sugar suggested elevated risk. We identified three major dietary patterns in Whites and African-Americans. The high fat/meat/potatoes pattern was observed in both race groups but was only positively associated with risk in Whites (odds ratio, 1.84; 95% confidence interval, 1.03-3.15). The vegetable/fish/poultry and fruit/whole grain/dairy patterns in Whites had significant inverse associations with risk. In African-Americans, there was a positive dose-response for the fruit/vegetables pattern (P(trend) < 0.0001) and an inverse linear trend for the legumes/dairy pattern (P(trend) < 0.0001). Our findings indicate that associations of certain food groups and overall dietary patterns with rectal cancer risk differ between Whites and African-Americans, highlighting the importance of examining diet and cancer relationships in racially diverse populations.

Dietary patterns and the risk of mortality: impact of cardiorespiratory fitness

While dietary patterns that are both predictive of chronic disease and mortality have been identified, the confounding effects of cardiorespiratory fitness have not been properly addressed. The primary objective was to assess the relation between dietary patterns with all-cause mortality, while controlling for the potentially confounding effects of fitness. This was a prospective cohort study. Participants consisted of 13 621 men and women from the Aerobics Center Longitudinal Study (ACLS). Participants completed a clinical exam and 3-day diet record between 1987 and 1999. Participants were followed for mortality until 2003. Reduced rank regression (RRR) was used to identify dietary patterns that predicted unfavourable total and high-density lipoprotein-cholesterol, triglyceride, glucose, blood pressure, uric acid, white blood cell and body mass index values. One primary dietary pattern emerged and was labelled the Unhealthy Eating Index. This pattern was characterized by elevated consumption of processed and red meat, white potato products, non-whole grains, added fat and reduced consumption of non-citrus fruits. The hazard ratio for all-cause mortality in the fifth vs the first quintile of the Unhealthy Eating Index was 1.40 (1.02-1.91). This risk estimate was reduced by 13.5 and 55.0% after controlling for self-reported physical activity and fitness, respectively. In this study the association between diet and overall mortality was, in large part, confounded by fitness.

Folate intakes and blood concentrations of adults in NHANES 2003‐2004

High folate intake (&gt;400μg) among older persons may result in adverse health outcomes and likely produce elevated serum folate concentrations, as shown in earlier National Health and Nutrition Examination Surveys (NHANES). We examined the impact of folate fortification and supplement use on intake and circulating folate concentrations of persons &gt;45 years in NHANES 2003‐2004 stratified by gender and four race‐ethnicity groups: non‐Hispanic white (NHW), non‐Hispanic black (NHB), Mexican American (MA) and Other (O).NHB and NHW men consumed less refined, non‐whole grains than O males (p=0.008) and less legumes than MA and O (p=0.019). MA women consumed more grains (p=0.007) than NHW and NHB races, and more legumes than all races (p=0.006). NHB men had the lowest mean red blood cell (RBC) folate concentrations (p&lt;0.001) and the lowest mean serum folate concentrations (p=0.003) of all races, while NHW women had the highest serum concentration (p=0.001). Female folate‐containing supplement users consumed more food folate than non‐supplement users (p=0.012). All supplement users are at risk of high serum folate concentrations and older (&gt;65 years), NHW women who use supplements are more likely to have elevated RBC folate concentrations. These findings highlight the need to better understand the effects of chronic exposure to elevated folate intakes.

Dietary Intake of Whole Grains

Objective: The objective of this study was to provide national estimates of whole-grain intake in the United States, identify major dietary sources of whole grains and compare food and nutrient intakes of whole-grain consumers and nonconsumers.Methods: Data were collected from 9,323 individuals age 20 years and older in USDA’s 1994–96 Continuing Survey of Food Intakes by Individuals through in-person interviews on two non-consecutive days using a multiple-pass 24-hour recall method. Foods reported by respondents were quantified in servings as defined by the Food Guide Pyramid using a new database developed by the USDA. Whole-grain and nonwhole-grain servings were determined based on the proportion, by weight, of the grain ingredients in each food that were whole grain and nonwhole grain. Sampling weights were applied to provide national probability estimates adjusted for differential rates of selection and nonresponse. Then, t tests were used to assess statistically significant differences in intakes of nutrients and food groups by whole-grain consumers and nonconsumers.Results: According to the 1994–96 survey, U.S. adults consumed an average of 6.7 servings of grain products per day; 1.0 serving was whole grain. Thirty-six percent averaged less than one whole-grain serving per day based on two days of intake data, and only eight percent met the recommendation to eat at least three servings per day. Yeast breads and breakfast cereals each provided almost one-third of the whole-grain servings, grain-based snacks provided about one-fifth, and less than one-tenth came from quick breads, pasta, rice, cakes, cookies, pies, pastries and miscellaneous grains. Whole-grain consumers had significantly better nutrient profiles than nonconsumers, including higher intakes of vitamins and minerals as percentages of 1989 Recommended Dietary Allowances and as nutrients per 1000 kilocalories, and lower intakes of total fat, saturated fat and added sugars as percentages of food energy. Consumers were significantly more likely than nonconsumers to meet Pyramid recommendations for the grain, fruit and dairy food groups.Conclusion: Consumption of whole-grain foods by U.S. adults falls well below the recommended level. A large proportion of the population could benefit from eating more whole grain, and efforts are needed to encourage consumption.