ASN Journals Offer a Variety of Scientific Perspectives

The Dietary Guidelines for Americans recommend that at least half of the grains we consume be in the form of whole grains.  This recommendation is based on years of cumulative scientific evidence and analysis linking the consumption of whole grains to a lower risk of type 2 diabetes, cardiovascular disease, and obesity.  The American Society for Nutrition (ASN) journals have been at the forefront of this research, publishing original research, scientific reviews, and opinion pieces that offer a variety of scientific perspectives on the nutritional benefits of whole grains versus refined grains.  Below is a small sampling of relevant articles from each of ASN’s four journals.

The American Journal of Clinical Nutrition (AJCN)

This study adds support for dietary guidance recommending the consumption of whole grains.

ASN member J. Philip Karl et al., authors of “Substituting Whole Grains for Refined Grains in a 6-wk Randomized Trial Favorably Affects Energy-balance Metrics in Healthy Men and Postmenopausal Women,” designed a randomized controlled trial to determine the effects of substituting whole grains for refined grains on energy-metabolism metrics and glycemic control.  Participants were divided into two groups: one group was given a diet emphasizing whole grains for six weeks, while the other group was given a refined grain-rich diet for the same time period.  The results of the trial “provide new mechanistic insights that support the consistent inverse associations between whole-grain intake and BMI and adiposity that have been documented in epidemiologic studies, but which have been largely unsubstantiated in previous clinical trials. As such, this study adds support for dietary guidance recommending the consumption of whole grains in place of refined grains.”

Current Developments in Nutrition (CDN)

Consumption of whole-grain foods…significantly reduces subjective hunger.

Expanding on the AJCN research findings discussed above, CDN author Lisa Sanders et al. hypothesized that “whole-grain intake may influence energy balance and body composition through effects on appetite and thus, energy intake.”  To evaluate the impact of whole-grain consumption on appetite, the authors conducted a review of randomized controlled trials, publishing their findings in “Effects of Whole Grain, Compared to Refined Grain, Intake on Subjective Measures of Appetite: A Systematic Review and Meta-Analysis.”  Their findings “support the view that consumption of whole-grain foods, compared to refined-grain controls, significantly reduces subjective hunger, and this may provide at least part of the explanation for the inverse associations between whole-grain food intake and risks for overweight, obesity and weight gain over time.”

The Journal of Nutrition (JN)

The link between whole grains and a lower risk of type 2 diabetes was found for all whole-grain products tested.

Working with data from the Danish Diet, Cancer, and Health cohort, which included 55,465 participants, Cecilie Kyrø et al. examined the associations between whole-grain intake and the risk of type 2 diabetes among a population with diverse whole-grain intake.  Their study, “Higher Whole-Grain Intake Is Associated with Lower Risk of Type 2 Diabetes among Middle-Aged Men and Women: The Danish Diet, Cancer, and Health Cohort,” found “consistent associations between high whole-grain intake and lower risk of type 2 diabetes.”  Specifically, men and women with whole-grain intakes in the highest quartile compared with those in the lowest quartile had a 34% and 22% lower risk of type 2 diabetes, respectively.  Moreover, the link between whole grains and a lower risk of type 2 diabetes was found for all the different types of cereals and whole-grain products tested, including wheat, rye, and oats.

Advances in Nutrition (AN)

Eleven meta-analyses…demonstrated that refined-grain intake was not associated with all-cause mortality.

Not everyone agrees that the evidence proves that whole grains confer a health benefit compared to refined grains.  In his Perspective, “Refined Grains and Health: Genuine Risk, or Guilt by Association?,” author Glenn A. Gaesser pointed out that “the recommendation to replace refined grains with whole grains “was based largely on results from studies that examined dietary patterns, not separate food groups.”  To support his assertion, the author noted that “11 meta-analyses of prospective cohort studies, which included a total of 32 publications with data from 24 distinct cohorts, demonstrated that refined grain intake was not associated with all-cause mortality, type 2 diabetes, cardiovascular disease, coronary heart disease, stroke, hypertension, or cancer.”

We invite you to click through to read these articles in detail in order to form your own scientific opinion.  You’ll also find many more articles on this topic by searching ASN journals.