Whole grains

Heart disease impacts people across all corners of the globe. In this study, researchers used data from 2000-2019 to quantify risk factors for heart disease in low- and middle-income countries. The researchers found that in low- and middle-income countries, the largest behavioral risk factor for ischemic heart disease was a diet low in whole grains. Additionally, high systolic blood pressure (the top number in the blood pressure reading) and high LDL (“bad”) cholesterol were linked with causing the highest disability-adjusted life years (a measure of overall disease burden).
Journal of the American Heart Association. 2021 Oct 5;10(19):e021024. doi: 10.1161/JAHA.121.021024. (Wang C et al.)

Larger waist sizes (as measured by waist circumference), high blood pressure, and high triglycerides are all signs of potential heart disease down the road, so researchers wonder how whole grains might play a role in these risk factors. In a study of 3,121 adults (average age 55), researchers analyzed the types of grain foods they ate and their health markers to see how different types of grains might relate to cardiometabolic risk. While all study participants got larger around the waist over the 18-year study period, eating the most whole grains (at least 48 grams whole grain per day, or at least 3 full servings) was linked with significantly smaller increases in waist size compared with eating the least whole grains (less than 8 grams whole grain per day, or less than a half serving). Additionally, eating more whole grains was also linked with significantly smaller increases in fasting blood sugar and systolic blood pressure, while eating more refined grains (4+ servings per day) was linked with greater increases in waist size and a smaller decline in triglycerides (a type of fat in the blood).
Journal of Nutrition. 2021 Jul 13;nxab177. doi: 10.1093/jn/nxab177. (Sawicki CM et al.)

Dietary guidelines around the world recommend making more of our grains whole, and researchers wonder if people in different countries are meeting these goals. In a study of 9,128 people across eight Latin American countries, the average person was eating less than one full serving (only 14.7 grams) of whole grain foods per day. Women and older adults were more likely to eat more whole grains, while people with lower incomes were less likely to eat more whole grains. The most commonly eaten whole grains in the survey were oatmeal, masa harina, whole wheat bread, corn chips, and wheat crackers.
European Journal of Nutrition. 2021 Jul 7. doi: 10.1007/s00394-021-02635-8.

Currently, Australian adults are only eating about 21 grams of whole grain per day. In this study, researchers quantified the savings in healthcare and reduction of lost productivity costs associated with a reduction in type 2 diabetes and heart disease through meeting the 48 grams per day whole grain recommendation. If 100% of the Australian adult population were to meet this whole grain goal, researchers estimate a savings of up to 750.7 million Australian dollars (AUD) in healthcare and lost productivity costs for type 2 diabetes, and an additional 717.4 million AUD in healthcare and lost productivity costs for heart disease, totaling more than a 1.4 billion AUD savings. On the low end, even if only 5% or 15% of Australian adults meet the 48 grams per day whole grain goal, there would still be an estimated savings total of 73.4 million AUD to 220.2 million AUD, respectively in healthcare and lost productivity costs related to both conditions.
Nutrients. 2021 May 29;13(6):1855. doi: 10.3390/nu13061855. (Abdullah MMH et al.)

Researchers studied the healthfulness of foods from different sources (schools, grocery stores, restaurants) in a group of 20,905 children and 39,757 adults in the period from 2003-2004 to 2017-2018. During this time, the proportion of children eating food of poor diet quality from schools decreased by more than half, from 56% to 24%. Most of these improvements occurred after 2010, in line with the Healthy Hunger Free Kids Act (which updated school nutrition standards) and were associated with kids eating more whole grains and less saturated fat, sugary drinks, and salt at schools. Additionally, the proportion of people eating food of poor diet quality from grocery stores decreased from 53% to 45% in kids and from 40% to 33% in adults, largely due to eating more whole grains and fewer sugary drinks. Food from restaurants tended to be less healthy, with very small improvements in diet quality over the study period. The researchers also found that school food improvements after 2010 were the most equitable improvements, as nutrition improved more evenly across racial and sociodemographic lines. On the other hand, most of the improvements in nutrition from grocery store or restaurant foods tended to be concentrated in high-income households.
JAMA Network Open. 2021 Apr 1;4(4):e215262. doi: 10.1001/jamanetworkopen.2021.5262. (Liu J et al.)

Randomized controlled trials are the “gold standard” of nutrition research as they can be used to establish cause and effect. In this article, researchers analyzed more than 20 randomized controlled trials to see how replacing refined grains with whole grains can impact health. They found that for adults both with and without risk factors of heart disease, substituting whole grains for refined can improve total cholesterol, LDL (“bad”) cholesterol, hemoglobin A1c (a measure of blood sugar control), and C-reactive protein (a measure of inflammation). 
Journal of the Academy of Nutrition and Dietetics. 2020 Nov;120(11):1859-1883.e31. doi: 10.1016/j.jand.2020.06.021. (Marshall S et al.)

Whole grain intake is still far below recommended levels worldwide, so researchers and policy makers wonder which strategies may be most useful for getting people to eat more whole grains. In this review, researchers analyzed studies about the various factors that influence whole grain consumption. They found that the main factors that are successful in increasing whole grain intake for both kids and adults are to “(i) increase the availability and the variety of foods containing [whole grains], (ii) improve their sensory appeal, (iii) reduce their purchase cost, (iv) use a familiarization period to introduce them to consumers (with a gradual increase in consumed amounts and repeated exposure), and (v) improve communication and labeling to enhance consumers’ ability to identify products with [whole grains].” The authors also note the benefits of public-private partnerships in their potential to increase whole grain consumption.
Nutrients. 2020 Aug; 12(8): 2217. Published online 2020 Jul 25. doi: 10.3390/nu12082217 (Meynier A et al.)

In this study, researchers calculated the reduced risk of heart disease associated with each serving of whole grain consumed. They were then able to model various scenarios of increasing whole grain consumption as a proportion of total grains, getting closer and closer to the recommended levels outlined in the US Dietary Guidelines. They found that if whole grain intake was increased to meet recommended levels (an increase of 2.24 servings of whole grain per day), the estimated direct medical cost savings from reduced risk of heart disease in the US was $21.9 billion annually. Further, they found that even small increases in whole grain intake can translate to substantial cost savings. A modest increase of just 0.25 servings of whole grains per day was associated with a savings of $2.4 billion annually.
Nutrients. 2020 Aug 3;12(8):E2323. doi: 10.3390/nu12082323. (Murphy MM et al.) 

Many dietary guidelines recommend that people make at least half their grains whole, yet little has been published on the availability of whole grain options at supermarkets. In a February 2020 audit of the flour aisle at four major supermarkets in metropolitan Sydney, researchers identified 130 different flour products. Of those, only 19% were whole grain flour. The majority of products were refined wheat flour. Not surprisingly, the whole grain flours contained significantly more fiber and protein.
Nutrients. 2020 Jul 10;12(7):2058. doi: 10.3390/nu12072058. (Hughes J et al.)

In a large study of nearly 200,000 US adults, those eating whole grains most frequently had a 29% lower risk of developing type 2 diabetes across the approximately 30-year study period than those rarely or never eating whole grains, even after adjusting for other lifestyle factors. When looking at specific whole grain foods, common foods like whole grain breakfast cereal, oatmeal, whole grain bread, and brown rice were all linked with a lower risk of type 2 diabetes. The exception was popcorn, which was linked with a higher risk of type 2 diabetes when eaten more than once per day, perhaps due to its association with butter sauces or sugary flavorings.
BMJ. 2020 Jul 8;370:m2206. doi: 10.1136/bmj.m2206. (Hu Y et al.)