President Donald Trump announced on Twitter on Wednesday that Rear Admiral Dr. Ronny Jackson will serve as the head of the Department of Veteran Affairs, replacing the current secretary of the department, David Shulkin.

Jackson had previously gained national attention when he gave his report on Trump's physical at a press conference in January, wearing a slick military suit displaying his various honors.

Trump's measurements and overall good health that Jackson reported were called into question in the media and on Twitter, where celebrities and journalists alike claimed he had given a low-ball measurement of the president's weight, giving birth to the "Girther Movement" conspiracy. Others, like CNN's Dr. Sanjay Gupta, claimed the numbers Jackson reported indicated that Trump had heart disease.

But Jackson has served in the White House for 12 years — personally caring for three presidents — and many former White House officials have lined up to defend his credibility.

Jackson's history as a combat doctor and experience working with soldiers is likely to serve him well in his new position, which be only the latest prominent role he has filled since he first started serving the country in the military.

Here is a rundown of his impressive and varied career: