Gabbard, who previously deployed as part of the Hawaii National Guard, said she started getting that streak during her first deployment.
“I started going gray in that one spot during and after my first deployment to Iraq,” the 2020 hopeful said during an Instagram Live broadcast.
Gabbard said that her hair helps commemorate those "who we lost there and the cost of war and why we fight so hard for peace.”
She said that she wouldn't dye the lock, apparently responding to a viewer's comment. “I don't know what you mean by 'fix.' If you mean dye, no, I’m not going to dye it," she said.
During an interview with Fox News host Tucker Carlson in May, Gabbard warned against a war with Iran, saying, "I know where this path leads us and I'm concerned because the American people don't seem to be prepared for how devastating and costly such a war would be."
Gabbard has snagged some attention during the 2020 cycle over her willingness to issue sharp criticism of her own party -- including one of the party's frontrunners.
During the second round of primary debates, Gabbard criticized Sen. Kamala Harris' record as a prosecutor.
"There are too many examples to cite but she put over 1,500 people in jail for marijuana violations and then laughed about it when she was asked if she ever smoked marijuana," Gabbard said of the California senator.