Rye

Whole grains are a popular healthy choice, but between whole wheat and whole rye, does it matter what you choose? Scientists put these grains to the test, randomly assigning 70 overweight but otherwise healthy, middle-aged adults to a 6-week diet replacing all of their grain foods with whole wheat, whole rye, or refined wheat. There were no significant differences between the whole wheat and whole rye groups. Despite seeing no significant changes to the composition of the gut microbiome, the refined wheat group saw a greater drop in fecal butyrate (compounds associated with better health). The whole grain groups were less likely to feel bloated and more likely to have regular stools, but also more likely to pass gas. The authors conclude that “whole-grain foods have the potential for maintaining or improving some subjective and functional markers of gut health compared to refined grain foods.”
Journal of Nutrition. 2017 Nov;147(11):2067-2075. (Vuholm S et al.)

Rye has long been studied for its satiating properties, but researchers wonder why rye leaves you feeling fuller for longer, and whether certain rye products are more filling than others. To test these differences, researchers provided various whole grain rye products (sourdough bread, flakes, puffs, and smoothies – each with the same number of calories) to 26 participants, who resumed their usual diet and exercise routine for two days between each intake of the rye samples. The rye puffs and rye bread, which have a porous structure, were the most filling, whereas the liquid beverage was the least filling. The porous structure of the rye puffs and bread is thought to stretch and fill up the stomach, signaling to your body that you’re satisfied.
Food Quality and Preference. 2017 September;60:178-187. (Pentikainen S et al.)

Rye, the principal grain consumed in traditional Scandinavian diets, is a fiber-rich food associated with satiety, weight management, and blood sugar control. In a European study, 158 people were assigned to either a standard Nordic diet (with lots of refined grains) or a healthy Nordic diet (rich in whole grains, fruits, vegetables, and low fat dairy) consuming their usual calorie level. Whole grain wheat and rye intake was verified using blood biomarkers. Researchers found that a high intake of whole grain rye (as measured using a plasma biomarker) was associated with decreased LDL (“bad” cholesterol), and an improved LDL to HDL ratio, while the biomarker for whole wheat consumption was not associated with any change in cholesterol.
PLoS One. 2014 Oct 23;9(10):e110827. (Magnusdottir OK et al.)

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.)