In a randomized controlled cross-over trial, 60 Danish overweight adults were assigned to an eight-week period of a diet high in either wholegrains or refined grains. After a six week ‘wash-out period’, another eight weeks followed where the diets were switched, from wholegrains to refined grains or vice versa.
Intake of the wholegrain rich diet reduced the energy intake and the body weight. The amount of wholegrain consumed, especially from rye, was directly associated with reduced blood concentrations of the inflammatory marker interleukin 6. Measurements of the gut microbiota and its activity could not reveal that the beneficial effects observed from the wholegrain diet were mediated through the gut biota.
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