He was still eager to serve, but after returning to the Fleet Marine Force two years after the IED hit, he felt the military's view of him and his service changed.
"The military wanted me to be a poster child," Jacobs, 34, told ABC News in a telephone interview on Tuesday. "I wanted to do my best for the military and the country."
Jacobs retired from the Navy in 2012 after serving eight years -- six of which he did as a combat wounded corpsman -- and being honored with a Bronze Star for his heroic actions. He hoped he could be part of something positive as a civilian.
In a few days, he's gearing up to climb Mount Kilimanjaro to do exactly that.
Jacobs leaves for Tanzania on Feb. 21 and is raising awareness through his climb for Waterboys, an initiative dedicated to bringing funding for clean water for communities in East Africa.
Waterboys brings together professional athletes and veterans in its mission. The organization has raised more than $4.6 million since it formed in 2015, according to director Nicole Woodie.
The medically retired Navy corpsman and others involved with Waterboys have raised $170,000 this year, according to Jacobs.
"It was definitely a good switch from the negative of being told that I'm not medically ready and I'm just gonna sit at a desk and have my uniform ready if a congressperson wants to meet with a wounded corpsman," Jacobs said. "I said, 'I can do that on the outside and still have an impact on the world.'"
It won't be Jacobs' first attempt at summmiting the mountain.
In 2018, he attempted to climb the 19,341-foot mountain, but made it to the 15,500-foot mark before having to turn back because of altitude sickness.
For this attempt, he's been training five days a week around San Diego, where he lives.
"I know people think San Diego is just all beach, but there's a lot of mountains around here," he said. "It's all about elevation change and cardio."
He feels good about this run, but is also grateful that he can bring awareness to a cause that's important to him.
"That's the reason why I'm home. ... Helping raise money for those villages and schools, that's why I'm home. If I can do something like that and improve their lives, I'm all about it," he said.
Jacobs himself also runs his own nonprofit, The Doc Jacobs Foundation, which helps active military and veteran families pay for sports programs for their children.
With his own charity and the work he's doing through others, he feels confident in his decision to have left the military.
"It's a bigger mission," he said. "The purpose of helping each other in this world."