Yes and no. People need to stay engaged, however, stress is a bad thing. It decreases immune function. Working 40 hours a week give or take is good. Working 80 hours a week with constant deadlines and crisis after crisis, not so much.
He's already on suppressants, got it. But I think this is his passion and he loves what he does so much that it's not the stress you're imagining. He's got good people to handle the all stressful stuff, and lots of cool toys to play with in the labs. My advice would be eat your oatmeal, kiss your wife and kids, tell them you love them, and giddyup into the day ahead.