Featured Research

from universities, journals, and other organizations

Another Reason To Avoid High-fat Diet: It Can Disrupt Our Biological Clock, Say Researchers

Date:
December 31, 2008
Source:
Hebrew University of Jerusalem
Summary:
Indulgence in a high-fat diet can not only lead to overweight because of excessive calorie intake, but also can affect the balance of circadian rhythms -- everyone's 24-hour biological clock, researchers have shown.

New results from experiments with laboratory mice suggest there is a cause-and-effect relation between diet and biological clock imbalance.
Credit: iStockphoto/Kristen Johansen

Indulgence in a high-fat diet can not only lead to overweight because of excessive calorie intake, but also can affect the balance of circadian rhythms – everyone’s 24-hour biological clock, Hebrew University of Jerusalem researchers have shown.

The biological clock regulates the expression and/or activity of enzymes and hormones involved in metabolism, and disturbance of the clock can lead to such phenomena as hormone imbalance, obesity, psychological and sleep disorders and cancer.

While light is the strongest factor affecting the circadian clock, Dr. Oren Froy and his colleagues of the Institute of Biochemistry, Food Science and Nutrition at the Hebrew University’s Robert H. Smith Faculty of Agriculture, Food and Environment in Rehovot, have demonstrated in their experiments with laboratory mice that there is a cause-and-effect relation between diet and biological clock imbalance.

To examine this thesis, Froy and his colleagues, Ph.D. student Maayan Barnea and Zecharia Madar, the Karl Bach Professor of Agricultural Biochemistry, tested whether the clock controls the adiponectin signaling pathway in the liver and, if so, how fasting and a high-fat diet affect this control. Adiponectin is secreted from differentiated adipocytes (fat tissue) and is involved in glucose and lipid metabolism. It increases fatty acid oxidation and promotes insulin sensitivity, two highly important factors in maintaining proper metabolism.

The researchers fed mice either a low-fat or a high-fat diet, followed by a fasting day, then measured components of the adiponectin metabolic pathway at various levels of activity. In mice on the low-fat diet, the adiponectin signaling pathway components exhibited normal circadian rhythmicity. Fasting resulted in a phase advance. The high-fat diet resulted in a phase delay. Fasting raised and the high-fat diet reduced adenosine monophosphate-activated protein kinase (AMPK) levels. This protein is involved in fatty acid metabolism, which could be disrupted by the lower levels.

In an article soon to be published by the journal Endocrinology, the researchers suggest that this high-fat diet could contribute to obesity, not only through its high caloric content, but also by disrupting the phases and daily rhythm of clock genes. They contend also that high fat-induced changes in the clock and the adiponectin signaling pathway may help explain the disruption of other clock-controlled systems associated with metabolic disorders, such as blood pressure levels and the sleep/wake cycle.


Story Source:

The above story is based on materials provided by Hebrew University of Jerusalem. Note: Materials may be edited for content and length.


Cite This Page:

Hebrew University of Jerusalem. "Another Reason To Avoid High-fat Diet: It Can Disrupt Our Biological Clock, Say Researchers." ScienceDaily. ScienceDaily, 31 December 2008. <www.sciencedaily.com/releases/2008/12/081228191054.htm>.
Hebrew University of Jerusalem. (2008, December 31). Another Reason To Avoid High-fat Diet: It Can Disrupt Our Biological Clock, Say Researchers. ScienceDaily. Retrieved October 21, 2014 from www.sciencedaily.com/releases/2008/12/081228191054.htm
Hebrew University of Jerusalem. "Another Reason To Avoid High-fat Diet: It Can Disrupt Our Biological Clock, Say Researchers." ScienceDaily. www.sciencedaily.com/releases/2008/12/081228191054.htm (accessed October 21, 2014).

Share This



More Health & Medicine News

Tuesday, October 21, 2014

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

CDC Revamps Ebola Guidelines After Criticism

CDC Revamps Ebola Guidelines After Criticism

Newsy (Oct. 21, 2014) The Centers for Disease Control and Prevention have issued new protocols for healthcare workers interacting with Ebola patients. Video provided by Newsy
Powered by NewsLook.com
First-Of-Its-Kind Treatment Gives Man Ability To Walk Again

First-Of-Its-Kind Treatment Gives Man Ability To Walk Again

Newsy (Oct. 21, 2014) A medical team has for the first time given a man the ability to walk again after transplanting cells from his brain onto his severed spinal cord. Video provided by Newsy
Powered by NewsLook.com
CDC Issues New Ebola Guidelines for Health Workers

CDC Issues New Ebola Guidelines for Health Workers

Reuters - US Online Video (Oct. 21, 2014) The U.S. Centers for Disease Control and Prevention has set up new guidelines for health workers taking care of patients infected with Ebola. Linda So reports. Video provided by Reuters
Powered by NewsLook.com
'Cadaver Dog' Sniffs out Human Remains

'Cadaver Dog' Sniffs out Human Remains

AP (Oct. 21, 2014) Where's a body buried? Buster's nose can often tell you. He's a cadaver dog, specially trained to find human remains and increasingly being used by law enforcement and accepted in courts. These dogs are helping solve even decades-old mysteries. (Oct. 21) Video provided by AP
Powered by NewsLook.com

Search ScienceDaily

Number of stories in archives: 140,361

Find with keyword(s):
Enter a keyword or phrase to search ScienceDaily for related topics and research stories.

Save/Print:
Share:

Breaking News:

Strange & Offbeat Stories


Health & Medicine

Mind & Brain

Living & Well

In Other News

... from NewsDaily.com

Science News

Health News

Environment News

Technology News



Save/Print:
Share:

Free Subscriptions


Get the latest science news with ScienceDaily's free email newsletters, updated daily and weekly. Or view hourly updated newsfeeds in your RSS reader:

Get Social & Mobile


Keep up to date with the latest news from ScienceDaily via social networks and mobile apps:

Have Feedback?


Tell us what you think of ScienceDaily -- we welcome both positive and negative comments. Have any problems using the site? Questions?
Mobile: iPhone Android Web
Follow: Facebook Twitter Google+
Subscribe: RSS Feeds Email Newsletters
Latest Headlines Health & Medicine Mind & Brain Space & Time Matter & Energy Computers & Math Plants & Animals Earth & Climate Fossils & Ruins