Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

In male monkeys, too much soy has adverse effects

03.05.2004


Researchers from Wake Forest University Baptist Medical Center Report



While soy may be beneficial to women in a variety of ways, research in monkeys suggests that it could have an adverse effect on the behavior of men, according to researchers from Wake Forest University Baptist Medical Center.

Reporting in the current issue of the scientific journal Hormones and Behavior, the researchers found that in male monkeys, "long-term consumption of a diet rich in soy isoflavones can have marked influences on patterns of aggression and social behavior." Isoflavones are a naturally occurring plant estrogen in soy protein.


"Although considerable attention has been directed at the potentially beneficial effects of isoflavones in reducing the risk of various cancers, osteoporosis, cardiovascular disease and postmenopausal symptoms, less effort has been invested in characterizing neurobehavioral effects," according to the study.

People have the concept that soy is only beneficial, said Jay R. Kaplan, Ph.D., professor of comparative medicine and anthropology, one of the investigators. "There is the thought that what is good for some is good for all and more is better."

But this research points out that not only does the dose make a difference, but so does the sex of the consumer, Kaplan said, adding that the study is consistent with emerging literature showing that soy can have a negative impact on the behavior of male rodents. Previous studies have shown no difference in aggression in females given large doses of soy, Kaplan said.

The study was done over 15 months with adult male monkeys who were divided into three groups and fed different amounts and types of protein. One group had about 125 mg of isoflavones a day. The second group had half that amount, and the third group’s protein came from milk and animal sources.

"In the monkeys fed the higher amounts of isoflavones, frequencies of intense aggressive and submissive behavior were elevated," according to the study. "In addition, the proportion of time spent by these monkeys in physical contact with other monkeys was reduced by 68 percent, time spent in proximity to other monkeys was reduced 50 percent and time spent alone was increased 30 percent."

Isoflavone levels of 125 mg per day are higher than amounts consumed by many Asians, who typically eat more soy than other populations. But, the isoflavone levels are comparable to levels found in many dietary supplements sold in the United States.

The FDA approved a statement in 1999 that said, "25 grams of soy protein a day, as part of a diet low in saturated fat and cholesterol, may reduce the risk of heart disease." Soy sales have grown from $940 million in 1990 to a projected $4 billion this year. Kaplan said that soy is the most widely used botanical by pre- and postmenopausal women.

"To the best of our knowledge, the present study may be the first to demonstrate that long-term consumption of isoflavones can alter patterns of agonistic and social behavior in primates," the researchers reported. "The present findings suggest that careful attention will be required to balance beneficial and potentially adverse effects."



Other researchers in the study included Michael R. Adams, D.V.M., professor of pathology, and Thomas C. Register, Ph.D., associate professor of pathology, at Wake Forest Baptist, as well as two researchers from Lehigh University’s Department of Biological Sciences.

The research was funded by NIH grants and a grant from the HF Guggenheim Foundation.

Media Contacts: Karen Richardson, krchrdsn@wfubmc.edu; Shannon Koontz, shkoontz@wfubmc.edu; at 336-716-4587

About Wake Forest University Baptist Medical Center: Wake Forest Baptist is an academic health system comprised of North Carolina Baptist Hospital and Wake Forest University School of Medicine. It is licensed to operate 1,282 acute care, psychiatric, rehabilitation and long-term care beds and is consistently ranked as one of "America’s Best Hospitals" by U.S. News & World Report.

Karen Richardson | EurekAlert!
Further information:
http://www.wfubmc.edu/

More articles from Studies and Analyses:

nachricht Rutgers-led innovation could spur faster, cheaper, nano-based manufacturing
14.02.2018 | Rutgers University

nachricht New study from the University of Halle: How climate change alters plant growth
12.01.2018 | Martin-Luther-Universität Halle-Wittenberg

All articles from Studies and Analyses >>>

The most recent press releases about innovation >>>

Die letzten 5 Focus-News des innovations-reports im Überblick:

Im Focus: In best circles: First integrated circuit from self-assembled polymer

For the first time, a team of researchers at the Max-Planck Institute (MPI) for Polymer Research in Mainz, Germany, has succeeded in making an integrated circuit (IC) from just a monolayer of a semiconducting polymer via a bottom-up, self-assembly approach.

In the self-assembly process, the semiconducting polymer arranges itself into an ordered monolayer in a transistor. The transistors are binary switches used...

Im Focus: Demonstration of a single molecule piezoelectric effect

Breakthrough provides a new concept of the design of molecular motors, sensors and electricity generators at nanoscale

Researchers from the Institute of Organic Chemistry and Biochemistry of the CAS (IOCB Prague), Institute of Physics of the CAS (IP CAS) and Palacký University...

Im Focus: Hybrid optics bring color imaging using ultrathin metalenses into focus

For photographers and scientists, lenses are lifesavers. They reflect and refract light, making possible the imaging systems that drive discovery through the microscope and preserve history through cameras.

But today's glass-based lenses are bulky and resist miniaturization. Next-generation technologies, such as ultrathin cameras or tiny microscopes, require...

Im Focus: Stem cell divisions in the adult brain seen for the first time

Scientists from the University of Zurich have succeeded for the first time in tracking individual stem cells and their neuronal progeny over months within the intact adult brain. This study sheds light on how new neurons are produced throughout life.

The generation of new nerve cells was once thought to taper off at the end of embryonic development. However, recent research has shown that the adult brain...

Im Focus: Interference as a new method for cooling quantum devices

Theoretical physicists propose to use negative interference to control heat flow in quantum devices. Study published in Physical Review Letters

Quantum computer parts are sensitive and need to be cooled to very low temperatures. Their tiny size makes them particularly susceptible to a temperature...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

VideoLinks
Industry & Economy
Event News

2nd International Conference on High Temperature Shape Memory Alloys (HTSMAs)

15.02.2018 | Event News

Aachen DC Grid Summit 2018

13.02.2018 | Event News

How Global Climate Policy Can Learn from the Energy Transition

12.02.2018 | Event News

 
Latest News

Researchers invent tiny, light-powered wires to modulate brain's electrical signals

21.02.2018 | Life Sciences

The “Holy Grail” of peptide chemistry: Making peptide active agents available orally

21.02.2018 | Life Sciences

Atomic structure of ultrasound material not what anyone expected

21.02.2018 | Materials Sciences

VideoLinks
Science & Research
Overview of more VideoLinks >>>