Divine Jewish law and tradition since the giving of the Torah to Moshe include commands for which no logical explanations are given: Observe a day of rest every seven days on Shabbat; wash your hands before eating; do not eat pork, let the land of Israel rest on every seventh Sabbatical year and do not plant crops; and numerous others.
Modern science has shown that the Sabbath rest is good for the body as well as the soul. Cleanliness protects the body from germs. Consuming pork can cause deadly trichinosis. Not planting crops once every seven years restores nutrients to the earth and makes it more fertile.
And now there is a surprising new reason for an obscure commandment required by Jewish law of men: putting on phylacteries during the morning prayers every weekday morning. These two black leather boxes with straps – called tefillin in Hebrew – are worn on one arm, hand and fingers and the other around the head. The straps worn on the hand are kissed during prayers. The boxes contain tiny scrolls of parchment inscribed with four verses from the Torah’s Book of Exodus and Book of Deuteronomy that include Shema Yisrael (Hear O’Israel).
Surprisingly, the word tefillin, which comes from the Hebrew word tefilla for “prayer,” is not even mentioned in the Bible. But the commandment is understood for the four similar versions of the text:
“And this shall serve you as a sign on your hand and as a reminder on your forehead—in order that the teaching of Hashem may be in your mouth—that with a mighty hand Hashem freed you from Egypt (Exodus 13:9, The Israel Bible).
Only the Talmud – the authoritative compendium of the Oral Law, a legal commentary on the Torah that explains how its commandments are to be carried out – are the tefillin mentioned by name and the details of their use explained.
Now, health benefits of wearing tefillin have been discovered by a Jewish associate professor of cardiovascular health at the University of Cincinnati’s College of Medicine who is also a cardiologist at the university’s medical center.
Dr. Jack Rubinstein conducted a pilot study that found that wearing tefillin is good for health though remote ischemic preconditioning that results in protection during heart attacks. The results were published online in the American Journal of Physiology-Heart and Circulatory Physiology.
He enrolled 20 Jewish men living in Greater Cincinnati — nine of whom wear tefillin every weekday morning and 11 who do not use them at all. They were aged 18 to 40 and all in good health. His team of researchers recorded baseline information on all participants during the early morning and then additional data after wearing tefillin for 30 minutes.
They measured the participants’ vital signs, drew blood for analysis of circulating cytokines (small secreted proteins released by cells that can cause inflammation and negatively impact the heart) and the function of their monocytes (a type of immune cell produced in the bone marrow that travels through the blood to body tissues in the body, where it becomes a macrophage, which surrounds and kill microorganisms, ingests foreign material, removes dead cells and boost immune responses). They also measured blood flow in the arm not wrapped with tefillin.
Several large population studies have found that Orthodox Jewish males (who wear tefillin almost daily) have decreased cardiovascular mortality compared to non-Orthodox counterparts. “We hypothesized that tefillin use is a relevant component in triggering a preconditioning effect.”
Tefillin are used for morning prayers for Jewish men over the age of 13 on an almost daily basis (except for Shabbat and the major Jewish holidays), wrote Rubinstein. “One is placed on the non-dominant arm around the bicep and the forearm in a pretty tight manner. It is never worn in a fashion as to preclude the blood flow. This is worn for about 30 minutes continuously. Prayers are sitting and standing so often you have to retighten the strap around your arm.”
Rubinstein noted that the binding of the arm and the discomfort users often report may serve as a “form preconditioning” and offer a substantial degree of protection against acute ischemic reperfusion injury (in which a section of the heart is deprived of oxygen and then damaged when re-oxygenated) that occurs as a result of a heart attack.
“One of the ways that protection occurs is through pain,” explained Rubinstein. “Feeling pain is actually a preconditioning stimulus.
We found people who wear tefillin in either the short or long term, recorded a measurable positive effect on their blood flow. That has been associated with better outcomes in heart disease.”
Blood flow was better in men who wore tefillin daily and improved in all participants after wearing it just once as part of the study, he continued. Men who wore tefillin daily also had fewer circulating cytokines, suggesting that near-daily use elicits an effect similar to that observed with other methods of eliciting remote ischemic preconditioning-like effect.
For years researchers have studied preconditioning by inducing small heart attacks in animal models and found that they protected the animal from larger, more serious heart attacks in the future. This same preconditioning could be used by partially occluding blood flow in one part of the body and thus serving as a protective element in another part of the body to lessen the injury, stated Rubinstein.
“The problem with translating this to people is we don’t know when someone will have the heart attack,” wrote Rubinstein. “It is almost impossible to precondition someone unless they are willing to do something daily to themselves. Tefillin use may in fact offer protection as it’s worn on an almost daily basis.”
Rubinstein says there are studies out of Israel that have found Orthodox men have a lower risk of dying of heart disease compared to non-Orthodox men. This protection is not found in Orthodox women who usually don’t wear tefillin.
This brings up the question about whether Jewish women may – or should – wear tefillin during their prayers like men. Some women who identify with non-Orthodox Jewish movements do. The Talmud mentions that Michal, the daughter of King Saul, wore phylacteries, as reputedly did the daughters of Rashi, (Rabbi Shlomo Yitzhaki, the noted medieval French rabbi and author of a comprehensive commentary on the Bible and the Talmud).
But according to an article by Rabbi Yehuda Shurpin of the Chabad organization’s Ask the Rabbi service, “Since time immemorial, the widely accepted practice in the Torah-observant community is that women do not wear tefillin.”
Tefillin is a time-bound positive commandment, meaning that it is something that must be done at a specific time, the rabbi explained. Women are generally exempt from such commandments. But even if they are exempt, shouldn’t they be encouraged to wear tefillin anyway of their own volition? After all, we find that most women do hear shofar on Rosh Hashana and shake the lulav on Sukkot, the Feast of Tabernacles, even though they are technically not required to. Why would tefillin be any different?
“Our first point of reference is the biblical prohibition against crossdressing…The great Talmudic sage Yonatan ben Uziel, in his elucidated translation of the Torah, sees this as precluding a woman from wearing a tallit or tefillin, since they are male apparel. Others, however, are of the opinion that the prohibition of crossdressing applies only to clothing worn for style or appearance, but it would not apply to ritual items like tefillin. Accordingly, this prohibition alone would not be sufficient reason for women to refrain from doing this mitzva,” wrote Shurpin.
“Halacha teaches that when someone does a non-obligatory pious act that is not performed by the vast majority of their peers, it draws undue attention to their excessive piety in an inappropriately ostentatious manner, and is to be discouraged,” the Chabad rabbi continues. “For this reason, there are some who say that women wishing to go the extra mile may not put on tefillin. This may help explain why women refrain from putting on tefillin publicly. However, it is not clear that this reason would apply to those who wish to do so in the privacy of their own homes.”
Finally, there are some limitations to the University of Cincinnati study, as it is small. “The finding of improved vascular function and reactivity associated with both acute and chronic use of tefillin is interesting, but it should be noted that no longitudinal [long-term] studies in humans have yet proven that young subjects with endothelial dysfunction will go on to develop advanced atherosclerosis or that improving vascular function at an early stage would lead to improved outcomes as such studies would take decades to complete,” Rubinstein said.
Despite this, the team wrote that their findings are interesting and important and should be followed up in additional research.