What they found in the initial study was that the average body mass index of travelers who are on the road 21 or more nights a month was higher than in travelers who were away from home one to six nights per month. For a 6-foot-tall person, the difference amounted to a 10-pound difference in weight.

That finding supports what Dr. Rundle said he suspected was a problem for traveling employees. “If you’re in your 30s and you’re traveling a lot and you’re eating poorly and you have poor access to physical activity, that starts to catch up with you,” he said. “Over the next 10 years or so, the consequences start to become things like high blood pressure and diabetes and obesity. Long-term chronic issues.”

His yet-unpublished sequel study looks more closely at business travelers’ mental health — an area both Dr. Cetron at the C.D.C. and Dr. Chen at the International Society of Travel Medicine said was important but fell outside their purview. It includes factors like alcohol abuse and accidents and injuries caused by lack of sleep and jet lag. “These are things that can have really immediate consequences for yourself and your career,” he said.

A Harvard Business Review article in 2015 noted that frequent business travel accelerates aging and increases the likelihood of suffering a stroke or heart attack, and that more than 70 percent of business travelers report some symptoms of an unhealthy lifestyle, including poor diet, lack of exercise, excess drinking, stress, mood swings and gastrointestinal problems. “All of which impair job performance,” it said.

If corporations are taking note, they’re not always taking action. “Travelers themselves are concerned about their health and the amount of time they’re away from home,” said Greeley Koch, executive director of the Association of Corporate Travel Executives, a nonprofit organization with board members from companies including Mastercard and Tesla. Policies to limit travel, or to make it less toxic through measures like upgrades to business class or added time for taking in fresh air during a work trip, depend on bosses and are entirely unregulated, he said. “It’s really a mixed bag when it comes to addressing these issues. It depends on the company.”

Doctors like Phyllis Kozarsky, a professor of medicine in the division of infectious diseases at Emory University School of Medicine and the medical director of TravelWell, a clinic in Atlanta for international travelers, said they see the need for more company attention to the issue.