Gray Hair – A New Discovery

by Rabbi Yair Hoffman

The Torah’s Perspective on Gray Hair

In the Torah, we find an important mitzvah related to gray hair in Vayikra 19:32: “Before a Saivah you should rise, and you shall honor the face of an old man, and you shall fear your G-d – I am the L-rd.”

The Hebrew word “Saivah” refers to someone with gray or white hair, symbolizing wisdom that comes with age. This mitzvah teaches us to show respect for elderly individuals by standing in their presence. But at what age does this mitzvah apply?

Most authorities, following the Rosh in Kiddushin 33a, consider someone to be a “Saivah” when they reach seventy years of age. However, the Rashbatz, citing Targum Unkelus, suggests this applies from age sixty. The Minchas Chinuch (#407) recommends being stringent and rising for someone who has reached sixty years, a view shared by the AriZal in Shaar HaMitzvos.

Interestingly, the third Lubavitcher Rebbe (in Responsa Tzemach Tzedek) notes that there’s an important connection between visible gray hair and this mitzvah. He explains that shaving one’s beard is problematic partly because it would make it difficult to identify who deserves this special kavod.

To Whom Does This Mitzvah Apply?

The mitzvah of rising before the elderly applies to all older people, whether they are Torah scholars or not. This was debated in the Talmud (Kiddushin 33a), with the halacha following Issi Ben Yehudah’s view that “Saivah” includes all older individuals. The reasoning seems to be that their life experience itself deserves respect.

When we fulfill this mitzvah, we also fulfill another important commandment: “Vehalachta bidrachav” (walking in Hashem’s ways). The Jerusalem Talmud teaches that Hashem Himself honors the elderly, so when we do so, we are emulating divine behavior.

What About Elderly Women?

Ashkenazic Jews generally follow the Sefer Chassidim (#578), which states that this obligation extends to elderly women as well. However, the Ben Ish Chai, citing the AriZal, holds that the mitzvah doesn’t typically apply to an older woman unless her husband is a Torah scholar.

Exceptions to the Rule

There are some situations where one is exempt from this mitzvah:

• If standing would interfere with one’s work for an employer
• If there would be a financial loss involved (though many poskim still advocate giving up one’s seat on public transportation as proper behavior)
• When holding a Sefer Torah (as the Talmud states, “Does a Sefer Torah stand before those that study it?”)

The Birchei Yoseph rules that one must stand even during davening (prayer). And when in doubt about whether someone has reached the age of seventy, Rav Ovadiah Yoseph zt”l rules that we should be stringent and assume they have reached this age.

The New Discovery

Recent research published in the prestigious journal Nature has revealed fascinating insights into why our hair turns gray as we age. To understand these findings let’s take a look at some special cells in our body called stem cells.

What Are Stem Cells?

Stem cells are the body’s repair team that Hashem put in our bodies. They can divide and create new cells that help maintain and fix tissue issues. Different types of stem cells have different jobs throughout the body.

One specific type, called melanocyte stem cells (McSCs), is responsible for hair color. These cells live inside our hair follicles (the tiny pockets in our skin where hair grows). Their job is to produce pigment-making cells called melanocytes, which give hair its color.

The Amazing Mobility of Melanocyte Stem Cells

What makes these McSCs special is their ability to move within the hair follicle and change their function based upon where they are. Scientists at NYU Grossman School of Medicine discovered that these cells need to be able to travel between different parts of the follicle to maintain hair color.

When a new hair is growing, these McSCs need to move downward in the follicle to a region called the “germ compartment.” Once there, they receive special signals (called WNT proteins) that tell them to develop into melanocytes and produce pigment for the growing hair.

After completing their job, these cells can actually return to their original state and location, ready for the next hair growth cycle. This back-and-forth movement and ability to change roles is quite unusual for stem cells, which typically only develop in one direction.

Why Hair Turns Gray

As we age, these McSCs start to lose their mobility. They get “stuck” in an area of the hair follicle called the “bulge” and can’t move down to where they need to be to receive the signals to produce pigment.

In their study, the researchers found that in younger mice, only about 15% of these stem cells became trapped. But in older mice, nearly half were immobilized! The trapped cells couldn’t produce pigment, resulting in gray hair.

Importantly, the cells that maintained their mobility continued to function properly for up to two years. This suggests that gray hair isn’t simply caused by stem cells wearing out, but rather by their loss of mobility and flexibility.

There may be a fascinating connection between this scientific discovery and a teaching from the Zohar. The Zohar in Parshas Pinchas (page 227b) offers an alternative reading of the verse in Vayikra: “Before the grey hair, arise” – teaching us to arise in doing teshuva (repentance) before we reach the age of having gray hairs.

This interpretation may take on a new twist in light of the new scientific uptiche or discovery. Just as stem cells need to maintain their mobility and adaptability to preserve hair color, we too must maintain spiritual mobility and adaptability to move between different areas of ruchnius. We must be able to recognize when we’ve fallen from the proper path and return through teshuva.

Scientists are now exploring ways to restore stem cell mobility, which could potentially prevent or reverse graying. Similarly, through Teshuvah, Torah study and mitzvos, we can maintain our spiritual vitality regardless of our physical age.

Whether our hair is colored or gray, the Torah teaches us to honor the wisdom that comes with age. The visible sign of gray hair serves as a reminder of the respect due to those who have accumulated life experience.

From a Torah perspective, gray hair is not merely a sign of aging to be concealed, but a crown of glory to be honored. Shlomo HaMelech teaches in Mishlei 16:31: “Gray hair is a crown of glory; it is gained in a righteous life.”

May we merit to fulfill this important mitzvah with understanding and sincerity, recognizing the nifla’os haBorei in how He fashioned us as well as in the remarkable gift that is Teshuvah.

The author can be reached at [email protected]