How four years in the White House have aged Obama

Heavy and grey is the head that wears the crown - a lesson that President Obama and many of his predecessors have learned the hard way. 

When Mr Obama takes the oath of office next Monday marking the beginning of his second term, it will not be the same smooth-cheeked, black-haired man who first joined the exclusive club of leaders of the free world in 2008. 

Comparing pictures of the 51-year-old commander-in-chief from four years to those taken more recently reveals a startling yet obvious truth: standing at the helm of the U.S. government takes a heavy physical toll. 

 The image on the left shows President-elect Obama just days before being sworn into office in January 2009; picture on the right shows the president delivering a speech on the fiscal cliff last month

Time machine: in his 2008 portrait, left, President Obama appear youthful, with black hair and smooth face, but four years later, the commander-in-chief looks much older, with crow's feet under his eyes and grey hair 

Draining job: President George W. Bush appeared smooth-cheeked and vigorous in his 2001 portrait, left, but at the end of his second term, after 9/11 attacks and two wars, Bush's face looked deeply lined  

 President Clinton went from a similar transformation in two terms, going from dark hair and healthy complexion to white tresses and bags under his eyes, right

In 1860, Abraham Lincoln was a brawny, sinewy man in his prime, left, but five years of war transformed him into a grizzled old man with sunken eyes and deep wrinkles, right 

Why presidents age quickly

Presidents face unabated, unfathomable stress. “You see it over a term,” said Ronan Factora, a physician specializing in geriatric medicine at the Cleveland Clinic. “It’s a good study of chronic stress on a person’s overall health.”

Changes in skin or hair are gradual, he said. “If you do have a stressful event, nothing is going to happen right away.” Nothing visible anyway. Inside the body, the pituitary gland jolts the adrenal gland, just above the kidneys. Hormones start coursing. Adrenaline cranks up heart rates and blood pressure. Cortisol, another hormone from the same gland, causes inflammation and preps the body for converting sugars into energy.

“It’s not intended that people would be chronically exposed to these levels,” said Sherita Golden, a physician at the Johns Hopkins Medical Bloomberg School of Public Health. Cortisol strains the circulatory system, battering artery walls. The hormone also thins the skin, makes muscles waste and bones lose mass. The immune system weakens, and viruses that cause colds and cold sores take hold. Sleep turns fitful.

“Your cognition slows, you may feel more depressed, your ability to concentrate goes down,” Factora said. “And it just builds on itself — a real cascade.”

The only known cure

There is one known treatment: exercise. “It is the best benefit a physician can recommend,” Factora said. “There is no drug that can present as many benefits as exercise can.”

Obama is a fiend for exercise. In hour-long workouts, he has been known to hit treadmills hard, weight train with arms and legs, build quickness through “plyos” or plyometrics — exercises that involve explosive movements. He also throws footballs, shoots basketballs and thwacks at golf balls.

His predecessors exercised, too, some of them fiercely. George W. Bush ran till his aging knees made cycling a better option. Presidents Carter and Bill Clinton jogged, while Ronald Reagan rode horses and split logs with such vigor, he once cut his thigh. President Gerald Ford performed a daily exercise regimen while still in his robe and PJs.

Good exercise leads to better thinking, brain-mapping has shown. “Exercise actually brings more blood flow,” explained Linda Fried, an epidemiologist and geriatrician at Columbia University. “Parts of the brain are activated and they’re associated with complex thinking and problem-solving.” Workouts also force a president to — truly, finally, deeply — rest. Only then can the relaxed brain start to make creative associations.

Infirmity and vice

The job has compounded certain human frailties. Most famous perhaps is the lethal case of pneumonia that 68-year-old William Henry Harrison caught at his inauguration. Woodrow Wilson’s stroke certainly limited his leadership of the country, and Franklin D. Roosevelt worked around the problems related to his polio more ably than might have been expected.

But daily habits also affect presidential well-being in lesser-known ways. Dwight D. Eisenhower was so dedicated to his form of exercise that he played 800 rounds of 18 holes over eight years as president, according to Evan Thomas, the author of “Ike’s Bluff: President Eisenhower’s Secret Battle to Save the World.” Then, in 1955, Eisenhower had a heart attack, and two years later, a stroke. Intestinal surgery came in between, all as he was staving off nuclear war and realigning Southeast Asia.

“Toward the end,” Thomas said, “he was taking an extra sleeping pill at night” — the powerful, old-school kind, with barbiturates. And that was on top of a nightly scotch, never more than five ounces, except when it was, Thomas said. “A couple of times he says to his doctor, ‘Let’s get drunk.’ ”

To the best of the public’s knowledge, recent presidents have not exacerbated their stress through bad behaviors such as drinking. Obama, however, confirmed that he had to kick a cigarette habit of unknown intensity at some midpoint in his first term.

The side effects of smoking might show up as those lines in his face, the doctors said. While sun exposure can also make a face look withered, Obama’s darker skin has melanin to alleviate UV ray damage. That same coloring, however, can make his white hair look more pronounced.

A special lot

Obama had a fitness test on Jan. 12, and the White House said the results would be released by February. His previous physical was in October 2011; it showed that he had added one pound since his February 2010 physical (his 2011 weight: 181, very good for a man who was then 50 and 6-foot-1).

Like all presidents since 1992, Obama has been under constant medical watch: a military physician is on hand wherever a president goes. Burton Lee,whom the first President Bush brought to the White House to monitor his health, agreed with Mariano that presidents are a special lot. They push their bodies and minds, and thus they develop a greater capacity to fight off infection. They shake enough hands to fell a lesser creature, he said.

But the mental intrusions — the sense that someone needs something from the president every moment of every day — are as insidious as the germs. “It’s just a phenomenally demanding job,” he said. “You never get one minute off.”

Despite the extraordinary stress levels, many recent presidents have lived well beyond normal life expectancy. Ronald Reagan and Gerald Ford died at 93; Jimmy Carter and the George H.W. Bush are 88. Doctors are coming to understand that stress may have an upside. “Human beings need some degree of stress to keep their systems tuned,” Fried said. “Some people enjoy the stimulation of it and the excitement and couldn’t live without it.”

Plus, human minds literally seek reasons to live. “Many people, as they get older, deeply care about future generations and the world’s survival,” Fried said. “If they have a chance to make a difference, that keeps people healthy.”