Stress, along with poor eating and sleeping habits, can challenge Trump

Being the leader of the Free World is no doubt one of the most stressful jobs possible, but how much stress affects President Trump is open to debate.

Still, psychiatrists including Bandy Lee, editor of the upcoming book The Dangerous Case of Donald Trump, worry about how Trump responds to what are likely stressful crises with fiery rhetoric that could provoke violence. 

There's evidence to support their concerns, given heightened terrorism concerns. 

Health company Sharecare did a voice analysis of Trump's stress during recent public appearances for USA TODAY. It found talking about firing former FBI Director James Comey, who was leading the Russia probe, did not appear to induce stress in Trump. Discussing the Islamic State did. 

Psychologist Melanie Greenberg, author of The Stress-Proof Brain, says the distinction between Trump's stress responses to ISIS and Comey could relate to the "controllability vs. uncontrollability of the stressor."  A group like ISIS is like "the bogeyman under the bed," she says. Research in rats and humans shows things that aren't controllable magnify how much stress we feel, she says.  

During the campaign debates, Sharecare did a voice analysis of Trump's stress and found he had relatively low levels during his most heated personal attacks on others and high levels when talking about policy. Former secretary of State Hillary Clinton had the opposite stress responses.

Mental health professionals say stress and mental health are related.

There's a "negative spiral where they sort of feed into each other," says Daisy Chang, a Michigan State University associate professor of psychology.  

Chang co-authored a new study that found sufficient sleep shields against both stress at work and impulsive, late night eating. USA TODAY reported recently that medical experts said Trump suffers from sleep deprivation and that his lack of exercise and poor eating habits coupled with stress could lead to health and behavior problems.  

"Self control can manifest in many, many dimensions," she says, citing eating, "ethical conduct and polite behavior."  It also gives you "more energy...and helps you better control your desire rather than letting your inner child run free," says Chang, whose study appeared in the Journal of Applied Psychology.

More:Is chronic sleep deprivation impairing President Trump's brain, performance?

Will Trump's exercise and eating habits catch up to him as stress mounts?