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AGING O »
Our interactive graphic simulates the commander-in-chief’s aging process

If there were any pundits who didn’t comment about President Obama’s noticeably grayer hair after he delivered his jobs speech last Thursday, I missed them.

The graying of Obama has become a theme of this presidency: to his supporters each patch of gray reflects another piece of the mess that George W. Bush left his successor to clean up; to his detractors the gray reflects the anxious condition of a man in way over his head—a head of once-pepper hair attractively flecked with salt to provide that all-important appearance of gravitas.

Every time I hear the president himself (or his wife Michelle or his friend/adviser Valerie Jarrett or a cable show host) remark on toll the job is taking on him, I wonder, would the hue of his buzzcut look pretty much the same had he lost the race for the U.S. Senate seat and remained in the relatively low-stress jobs of Illinois state senator and lecturer at the University of Chicago Law School?

I sought the opinion of Dr. Charles Zugerman, associate professor of clinical dermatology at the Feinberg School of Medicine of Northwestern University and on the staff of Northwestern Memorial Hospital. [Full disclosure: He’s my doctor and every time I see him we discuss not only the state of my skin, but also the day’s political news—and more interestingly, Teddy Roosevelt or Woodrow Wilson or the building of the Panama Canal. Zugerman has a deep knowledge and curiosity about American history and the presidency.]

Is it genetics or is it stress from the job that caused the president to go gray?  Here’s the doctor’s answer:  

“To understand the answer to this question, one must understand how hair grows. Hair grows from bulbs buried deep in the scalp through follicles, which conduct the hair to the surface of the scalp. Hair is made of keratin, which is made by cells called keratinocytes, which are located in and around the hair bulb. The color of hair comes from a compound called melanin, which is made by melanocytes—which are also in and around hair bulbs in the scalp. There are two types of melanin. Eumelanin is dark brown or black, whereas pheomelanin is yellow or red. By combining these two types of melanin, the body can create any color hair.

“Hair growth goes through cycles where 90 percent of hair at any one time is actively growing (anagen phase) and 10 percent is in a resting phase (telogen). The resting phase is much shorter (three months) than the growing phase (years). When the hair in telogen phase begins to grow again, new keratinocytes are recruited to provide the keratin, which provides the structure for the hair shaft. New melanocytes are also recruited to provide melanin creating hair color. Unfortunately, over the years of going through these growth cycles, melanocytes are depleted faster than keratinocytes possibly on a genetic basis. Thus, over the years, fewer melanocytes are present and less melanin ends up in hair shafts. With less melanin present, the hair turns gray, and if no melanin is present, the hair turns white. 

“The question of whether stress can cause hair to gray faster is unanswered scientifically. It certainly is a common observation that people like President Obama seem to gray rapidly when they are subjected to intensely stressful situations. The implication is that stress in some way affects the survival or function of the melanocytes, which create hair color. One can postulate that stress can either increase production of powerful molecules called free radicals, which will decrease melanocyte function, or that stress may stimulate a hormonal response, which prevents melanocytes from depositing pigment in the hair shaft. Unfortunately, there is little data to answer this question.”

In other words, Zugerman says, we don’t really know. Were Barack Obama still hanging out in Springfield and in Hyde Park, he might look just as gray—or maybe not quite so gray. 

“The president, like most aging adults, is developing gray hair (depletion of melanocytes around hair bulbs) at a rate that is controlled by his genetics,” Zugerman concludes. “Stress may speed this process up but the mechanism for this has not been specifically determined by the scientific community.” 

Back in 2009, Chicagomag.com created an interactive graphic on the graying of Obama—and also included photos of his predecessors, Bill Clinton and George W. Bush, on the year they took office versus the year they left. Take a look, click up the years, and see how it matches up with reality.

Photograph: Chicago Tribune