The diet influences secretion patters of hormones responsible for hunger and satiety, as well as hormones associated with metabolic syndrome. In this way the diet can help dieters persist over the long run, and reduce risk factors for diabetes and cardiovascular disease.
The research was carried out by research student Sigal Sofer under the auspices of Prof. (Emeritus) Zecharia Madar, at the Institute of Biochemistry, Food Science and Nutrition at the Hebrew University's Robert H. Smith Faculty of Agriculture, Food and Environment. (Prof. Madar is now Chief Scientist at Israel’s Ministry of Education.)
Sofer randomly assigned 78 police officers to either the experimental diet (carbohydrates at dinner) or a control weight loss diet (carbohydrates throughout the day). 63 subjects finished the six-month program.
The researchers examined the experimental diet's effect on the secretion of three hormones: leptin, considered to be the satiety hormone, whose level in the blood is usually low during the day and high during the night; ghrelin, considered the hunger hormone, whose level in the blood is usually high during the day and low during the night; and adiponectin, considered the link between obesity, insulin resistance and the metabolic syndrome, whose curve is low and flat in obese people.
"The idea came about from studies on Muslims during Ramadan, when they fast during the day and eat high-carbohydrate meals in the evening, that showed the secretion curve of leptin was changed,” explained Prof. Madar.
The researchers found that the innovative dietary manipulation led to changes in daylight hormonal profiles in favor of the dieters: the satiety hormone leptin’s secretion curve became convex during daylight hours with a nadir in the late day; the hunger hormone ghrelin’s secretion curve became concave, peaking only in the evening hours; and the curve of adiponectin, considered the link between obesity, insulin resistance and the metabolic syndrome, was elevated. At the same time this dietary pattern led to lower hunger scores, and better anthropometric (weight, abdominal circumference and body fat), biochemical (blood sugar, blood lipids) and inflammatory outcomes compared to the control group.
The findings suggest there is an advantage in concentrating carbohydrate intake in the evening, especially for people at risk of developing diabetes or cardiovascular disease due to obesity. "The findings lay the basis for a more appropriate dietary alternative for those people who have difficulty persisting in diets over time," said Prof. Madar. "The next step is to understand the mechanisms that led to the results obtained."
The study was published in two continuous papers: "Greater weight loss and hormonal changes after 6 months diet with carbohydrates eaten mostly at dinner" (published in Obesity) and "Changes in daily leptin, ghrelin and adiponectin profiles following a diet with carbohydrates eaten at dinner in obese subjects" (published in Nutrition, Metabolism & Cardiovascular Diseases).
Sources of support for the study include Meuhedet Medical Services, Israel; the Israeli Police Force; the Kaplan Medical Center in Rehovot, Israel (for Dr. Fink); the Israel Diabetes Association; and the Israel Lung and Tuberculosis Association (for Prof. Eliraz).
For information, contact:Dov Smith, Hebrew University Foreign Press Liaison
Dov Smith | Hebrew University of Jerusalem
Laser activated gold pyramids could deliver drugs, DNA into cells without harm
24.03.2017 | Harvard John A. Paulson School of Engineering and Applied Sciences
What does congenital Zika syndrome look like?
24.03.2017 | University of California - San Diego
Astronomers from Bonn and Tautenburg in Thuringia (Germany) used the 100-m radio telescope at Effelsberg to observe several galaxy clusters. At the edges of these large accumulations of dark matter, stellar systems (galaxies), hot gas, and charged particles, they found magnetic fields that are exceptionally ordered over distances of many million light years. This makes them the most extended magnetic fields in the universe known so far.
The results will be published on March 22 in the journal „Astronomy & Astrophysics“.
Galaxy clusters are the largest gravitationally bound structures in the universe. With a typical extent of about 10 million light years, i.e. 100 times the...
Researchers at the Goethe University Frankfurt, together with partners from the University of Tübingen in Germany and Queen Mary University as well as Francis Crick Institute from London (UK) have developed a novel technology to decipher the secret ubiquitin code.
Ubiquitin is a small protein that can be linked to other cellular proteins, thereby controlling and modulating their functions. The attachment occurs in many...
In the eternal search for next generation high-efficiency solar cells and LEDs, scientists at Los Alamos National Laboratory and their partners are creating...
Silicon nanosheets are thin, two-dimensional layers with exceptional optoelectronic properties very similar to those of graphene. Albeit, the nanosheets are less stable. Now researchers at the Technical University of Munich (TUM) have, for the first time ever, produced a composite material combining silicon nanosheets and a polymer that is both UV-resistant and easy to process. This brings the scientists a significant step closer to industrial applications like flexible displays and photosensors.
Silicon nanosheets are thin, two-dimensional layers with exceptional optoelectronic properties very similar to those of graphene. Albeit, the nanosheets are...
Enzymes behave differently in a test tube compared with the molecular scrum of a living cell. Chemists from the University of Basel have now been able to simulate these confined natural conditions in artificial vesicles for the first time. As reported in the academic journal Small, the results are offering better insight into the development of nanoreactors and artificial organelles.
Enzymes behave differently in a test tube compared with the molecular scrum of a living cell. Chemists from the University of Basel have now been able to...
20.03.2017 | Event News
14.03.2017 | Event News
07.03.2017 | Event News
24.03.2017 | Materials Sciences
24.03.2017 | Physics and Astronomy
24.03.2017 | Physics and Astronomy