From The Washington Post which has a nice image wipe to compare pictures of the past few Presidents during their first term and last.
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.”