Simply replacing refined grains with whole grains yields tangible health results, with an effect on weight and inflammation, according to Danish research.
And for once, these effects observed for whole grains, which provide more fermentable substrates than their refined equivalents, do not seem to go through a modification of the intestinal microbiota.
This is what researchers observed in a large Danish study conducted by the National Food Institute of the Technical University of Denmark, and published in the journal Gut. This is the most comprehensive study to date on the effects of replacing refined grains with whole grains.
Whole grains: markers of inflammation decrease
The benefits of whole grains are already widely documented, especially in terms of reducing the risk of developing cardiovascular disease. The study involves 50 adults at risk of developing cardiovascular disease or type 2 diabetes, who for 8 weeks ate refined grains, and for another 8 weeks switched to whole grains. A 6-week wash-out separated the two intervention periods.
Blood test results, showing the switch to whole grains, lead to a reduction in markers of inflammation, especially for rye.
Whole grain: weight loss and feelings of fullness
Another observation, and not the least, the volunteers eat less during the whole cereal period, which is probably explained by the more marked satietogenic effect. Consequence: most of the participants lost a little weight during the whole grain period.
On the other hand, on the basis of DNA sequencing applied to the stools of the participants, no major change in the composition of the microbiota appeared between the two periods. Nor are the results of the hydrogen test, plasma short chain fatty acids, intestinal integrity and transit time.
Roager HM et al.Whole grain-rich diet reduces body weight and systemic low-grade inflammation without inducing major changes of the gut microbiome: a randomized cross-over trial.BMJ, Gut