(Ivanhoe Newswire) – Brown is better when it comes to rice, according to
researchers. Brown rice may have the added advantage over white rice of offering
protection from high blood pressure and atherosclerosis ("hardening of the
arteries").
New research by Satoru Eguchi, Associate Professor of Physiology at the
Cardiovascular Research Center and Department of Physiology at Temple University
School of Medicine, Philadelphia, suggests that a component in a layer of tissue
surrounding grains of brown rice may work against angiotensin II. Angiotensin II
is an endocrine protein and a known culprit in the development of high blood
pressure and atherosclerosis.
The subaleurone layer of Japanese rice, located between the white center of the
grain and the brown fibrous outer layer, is rich in oligosaccharides and dietary
fibers, making it particularly nutritious. However, when brown rice is polished
to make white rice, the subaleurone layer is stripped away and the rice loses
some of its nutrient value.
The Temple team and their colleagues at the Wakayama Medical University
Department of Pathology and the Nagaoka National College of Technology
Department of Materials Engineering in Japan sought to delve into the mysteries
of the subaleurone layer to make a case for leaving it intact when rice is
processed. Because angiotensin II is a perpetrator in such lethal cardiovascular
diseases, the team chose to focus on learning whether the subaleurone layer
could somehow inhibit angiotensin II before it wreaks havoc.
During their analysis, the team found that subaleurone components that were
selected by an ethyl acetate extraction inhibited angiotensin II activity in the
cultured vascular smooth muscle cells. This suggests that the subaleurone layer
of rice offers protection against high blood pressure and atherosclerosis. It
could also help explain why fewer people die of cardiovascular disease in Japan,
where most people eat at least one rice-based dish per day, than in the U.S.,
where rice is not a primary component of daily nutrition.
"Our research suggests that there is a potential ingredient in rice that may be
a good starting point for looking into preventive medicine for cardiovascular
diseases," Dr. Eguchi was quoted as saying. "We hope to present an additional
health benefit of consuming half-milled or brown rice [as opposed to white rice]
as part of a regular diet."
Source: Presented at the annual Experimental Biology conference, Anaheim, CA,
April 24-28, 2010.