|
|
 |
FEBRUARY 2010 |
|
|
|
|
|
|
|
| The Secret Seven |
“A land of wheat and barley, and (grape) vines and fig-trees and pomegranates; a land of olive-trees and (date) honey.”
- Deuteronomy 8:8
By Amanda Jaffe-Katz
Following the start of the academic year in 1924, Technion held its formal opening ceremony 85 years ago on February 9, 1925, officially becoming Israel’s first modern university. This occasion coincided with the Tu B’Shvat holiday, also known as the New Year for Trees. The holiday custom is to eat produce from the seven species abundant in the Land of Israel. What is the significance of these fruits for our health and nutrition, and what are the dietary implications for including them in our daily menu?
Prof. Michael Aviram of the Rappaport Faculty of Medicine was the first to show, more than a decade ago, that the most effective fruits for delaying the development of heart and vascular diseases are the
pomegranate, the grape (red wine) and
olive oil, which contain especially active antioxidants. “Oxidation of cholesterol is of central importance in its deposition in the artery wall and could cause blockage of the blood supply to the heart and brain, a phenomenon that causes heart attack or stroke,” Aviram, incumbent of the Tanenbaum Chair in Preventive Medicine, explains.
Current research (2010) published in two leading journals, Nutrition and Atherosclerosis, reports that the antioxidants in pomegranates not only hinder the oxidation of cholesterol in the first place, but even augment the breakdown of already oxidized cholesterol. Aviram’s research group at Technion’s Lipid Research Laboratory exposed this dual mechanism which protects us against cardiovascular disease and stroke.
Research published in the Journal of Agricultural and Food Chemistry Interaction in 2009 illustrates the beneficial properties of
dates (number seven on the Biblical inventory) in protecting against atherosclerosis. This study analyzed, for the first time, the effect of eating Medjool or Hallawi dates on serum glucose, lipids, and oxidative stress in healthy volunteers. Says Aviram, director of the Legacy Heritage Clinical Research Institute at Rambam Medical Center, “We found that eating 100 grams of dates daily over a one-month period did not cause an increase in blood sugar levels in healthy volunteers. Not only was this found but the level of fats (triglycerides) in the blood decreased significantly, as well as the amount of oxidation of fats in the blood.”
Aviram also questioned the possible antioxidative properties of olive oil and leaves. After one week of an olive oil-enriched diet, the LDL susceptibility to oxidation was significantly reduced. Similar results were found with consumption of extract of olive leaves. The researchers concluded that olive oil and olive leaves enrich LDL with oleic acid and with some unique phenolics, inhibiting LDL oxidation and atherosclerosis development. “These results can explain the low rate of cardiovascular diseases attributed to the Mediterranean diet,” says Aviram.
“Olive oil is the main source of fat in the Mediterranean diet,” explains Dr Ayelet Fishman, senior lecturer and food analysis expert in the Faculty of Biotechnology and Food Engineering. She is working on environmentally friendly methods to synthesize the beneficial antioxidants from olives. “The potent antioxidants in olives assist in reducing oxidative stress in the body, which is associated with mental diseases, cancer, and diabetes as well as atherosclerosis.”
Hydroxytyrosol, an important phenol present in olives, has exceptional antioxidant, antimicrobial, and anticarcinogenic activities and could be beneficial to health if incorporated into other foods such as bread or yoghurt. “Despite its great potential, its commercial availability is limited, and my research at the Laboratory for Applied and Molecular Biocatalysis is directed toward using biocatalysts to transform an inexpensive and abundant substrate - 2-phenylethanol - into hydroxytyrosol,” Fishman explains.
To conclude our agronomic survey sourced in the Holy Book, Fishman, recipient of the 2008 Alfred and Yehuda Weissman Award for Excellence in Teaching, further elucidates the hidden secrets of the remaining species.
“Barley, mainly used for making beer and whiskey but also for baking, contains all eight essential amino acids that the body cannot synthesize and must obtain from food,” she comments.
“Figs contain one of the highest sources of calcium as well as many antioxidants, and are thus considered to be a very healthy snack,” Fishman says.
Barley, whole wheat and figs are also rich in dietary fiber. “Dietary fiber is the indigestible portion of carbohydrates that undergoes full or partial digestion in the large intestine. Dietary fiber intake is inversely associated with the incidence of coronary heart disease and type II diabetes. Most of the available data also show the ability of whole grains to prevent weight gain and obesity as well as some types of cancers,” Fishman adds.
Bon Appétit, Be’Teavon, and Good Health!
Did You Know?
When Technion held its formal opening ceremony 85 years ago on February 9, 1925, the date coincided with the Tu B’Shvat holiday. The Knesset, modern Israel’s parliament, celebrates its official birthday on Tu B’Shvat - also known as the New Year for Trees. The holiday custom is to eat fruits from the Biblical seven species. |
|
|
|
© 2010 Technion-Israel Institute of Technology, Division of Public Affairs and Resource Development
All rights reserved. If you wish to use any text or graphics contained herein, please contact focus@tx.technion.ac.il |
|
The Secret Seven
