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Whole Wheat Can Improve Inflammation and Influence Gut Bacteria

Researchers are increasingly turning to gut bacteria to learn more about complex conditions such as inflammation. To study this relationship, scientists randomized 63 overweight and obese adults to a diet containing either whole grains (in the form of shredded wheat) or refined grains (in the form of white bread and crackers) for 4-8 weeks. In addition to decreased inflammation in the whole grain group (a good thing!), the scientists found that one of the most abundant beneficial plant compounds (ferulic acid) from whole wheat is released and absorbed in the gut, where it is likely metabolized. In line with other studies on how whole grains improve gut health and diversity, the researchers also found that whole-wheat consumption positively influenced bacterial communities in the study participants.
American Journal of Clinical Nutrition. 2015 Feb;101(2):251-61. (Vitaglione P et al.)

Antioxidants in Whole Wheat Unaffected During Baking

Whole grains are starting to gain recognition as being rich sources of antioxidants, but many wonder if these antioxidants are affected during processing, such as bread baking. To test this theory, scientists at the University of Maryland measured phenolic acid (antioxidant) content in flour, dough, and bread fractions from three whole and refined wheat varieties. As expected, “all phenolic acids measured were more abundant in whole wheat than refined samples.” The researchers also found no significant change in antioxidant levels after the breads were baked. “Thus, the potential phytochemical health benefits of total phenolic acids appear to be preserved during bread baking.”
Journal of Agricultural and Food Chemistry. 2014 Oct 20 [Epub ahead of print] (Lu Y et al.)

MANY ANTIOXIDANTS IN WHOLE GRAINS

While fruits and vegetables are known as sources of healthy antioxidants and phenolic compounds, research increasingly shows that whole grains contain them too. In this review, researchers analyzed the total phenolic contents, phenolic acid profile and antioxidant activity of several whole grains, including wheat, corn, rice, barley, sorghum, rye, oat and millet. The review shows that whole grains contain a number of phytochemicals (including antioxidants) and significantly exhibit antioxidant activity. Researchers conclude that the consumption of whole grains is considered to have significant health benefits including prevention of chronic diseases such as cardiovascular disease, diabetes, and cancer because of the contribution of phenolic compounds. 
Critical Reviews in Food Science and Nutrition. 2014 July 30. [epub ahead of print] (Van Hung P et al.)

Rye Crispbread Satisfies Appetite Better

Wondering what to have for breakfast? Researchers in Sweden, where rye has been the go-to grain for centuries, set out to compare two breakfast bread choices: whole grain rye crisp bread and (refined) white wheat bread. Although subjects ate similar amounts of each food for breakfast, they reported higher fullness, lower hunger, and less desire to eat after consuming the rye crisp than after eating the white bread. When study participants were allowed to eat as much as they wanted at lunch later that day, those who ate rye crisp for breakfast ate about 8% fewer calories at lunch.
Nutrition Journal. 2014 Mar 25;13(1):26. (Forsberg et al.)

Whole Wheat May Improve Intestinal Wall Integrity

“Leaky gut” is now widely accepted as a contributor to many diseases. Scientists at Denmark’s National Food Institute and the Technical University of Denmark conducted a 12-week energy-restricted intervention with 70 postmenopausal women to observe the effect of a whole wheat diet (n=37) vs a refined wheat diet (n=33). Women who ate the whole wheat diet had significant increases in beneficial bifidobacteria, and an unexpected increase in “trans-epithelial resistance,” a measure of the permeability of the intestinal wall that shows a decrease in “leaky gut.”
European Journal of Clinical Nutrition. 2013 Dec; 67(12):1316-21. (Christensen et al.)

Higher Whole Grain Intake Linked to Lower Distal Colon Cancer

Scientists at the Danish Cancer Society Research Center collaborated on a study to investigate the link between whole grain intake and colorectal cancer. Rather than rely on whole grain intake estimation, they measured levels of alkylresorcinols, which are biomarkers of whole grain rye and wheat intake, in 1372 colorectal cancer patients and an equal number of controls. They found that those with the highest whole grain intake had the lowest risk of distal colon cancer, but did not find a correlation with colon cancer overall, with proximal colon cancer or with rectal cancer.
Journal of the National Cancer Institute. 2013 Dec 7 [Epub ahead of print] (Kyrø et al.) 

Kernel Rye Bread has Lowest Glycemic Impact

To explore differences within the universe of whole grain food options, scientists at Aarhus University in Denmark conducted a randomized cross-over study involving 15 subjects with metabolic syndrome. The subjects sample four kinds of bread: rye bread made with intact kernels, whole wheat bread, whole wheat bread with concentrated arabinoxylan, or whole wheat bread with beta-glucan. The rye kernel bread scored highest on a variety of measures, while the beta-glucan sample also scored well.
European Journal of Clinical Nutrition. 2013 Nov 20 [Epub ahead of print] (Hartvigsen et al.)

Whole Wheat, Rye Don’t Improve Insulin Sensitivity in 12 Week Trial

Epidemiological studies suggest a relationship between whole grain intake and insulin sensitivity. In an effort to investigate this possible relationship a randomized controlled trial was conducted by a group of European scientists. One hundred and forty six individuals were recruited in two European cities (Kuopio, Finland and Naples, Italy) and randomized into two groups. One group consumed a diet based on refined grains and the second group was given a diet based on whole grains. After a 12-week period where good adherence was achieved, there was no significant difference in insulin sensitivity measures between the two groups. 
Clinical Nutrition. 2013. [Epub February 8, 2013] (Giacco et al.)

Blood Test Confirms Whole Grain Consumption Levels

Documenting the benefits of whole grains often depends on asking people to recall how often they eat whole grain foods, a process subject to less-than-precise memories and lack of understanding of just what constitutes a whole grain food. Now scientists at Uppsala University in Sweden have provided further evidence that blood levels of alkylresorcinols – a type of fat found in the bran of rye and wheat but in few other foods — can serve as more objective evidence of regular consumption of wheat and rye.  The researchers asked 72 adults to keep detailed, weighed records of everything they ate for 3 days, on two separate occasions, then tested the levels of alkylresorcinols in their blood. They found a very reliable relationship between the foods eaten and the blood levels measured.
The Journal of Nutrition, September 1, 2011. [Epub ahead of print July 2011]

RCT Shows Whole Grains Reduce Blood Pressure

In a randomized control trial of 233 healthy, middle-aged volunteers, subjects spent 4 weeks consuming a run-in diet of refined grains, and then were randomly allocated to the control diet (refined), a whole wheat diet, or a whole wheat and whole oats diet for 12 weeks. Each group consumed 3 daily portions of the specific grains. Systolic blood pressure and pulse pressure were significantly reduced by 6 and 3 mm HG, respectively, in the whole grains groups compared to the control refined group. Researchers at the University of Aberdeen concluded that this blood pressure decrease would decrease the incidence of coronary artery disease and stroke by 15-25% respectively.
American Journal of Clinical Nutrition, October 2010; 92(4):733-40. Epub August 4, 2010

Rye Reduces Body Weight Compared to Wheat

In this study conducted at Lund University in Sweden, mice were fed whole grain diets based on either wheat or rye, for 22 weeks. Body weight, glucose tolerance, and several other parameters were measured during the study. The researchers concluded that whole grain rye “evokes a different metabolic profile compared with whole grain wheat.” Specifically, mice consuming the whole grain rye had reduced body weight, slightly improved insulin sensitivity, and lower total cholesterol.
Nutrition. February 2010; 26(2): 230-9. Epub 2009 Jul 31.

Rye Bread Satisfies Longer than Wheat

At the Swedish University of Agricultural Sciences in Uppsala, researchers fed rye bread (with three varying levels of rye bran) and wheat bread to 16 people, then asked them to rate their appetite (hunger, satiety and desire to eat) for 8 hours afterward. [It’s not known if the wheat bread was whole wheat or refined wheat.] All through the morning and into the afternoon, the three rye bread breakfasts all decreased hunger and desire to eat, compared to the wheat bread control, with the rye bread containing the highest level of bran providing the strongest effect on satiety.
Nutrition Journal. August 26, 2009; 8:39

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