Vicki, 56, shared a current picture of Brianna, 31, and Ryan Culberson on Instagram.
"Just wanted to share this incredible photo of Briana and @ryan_culberson. Together they have lost over 85 lbs since last summer," the reality star wrote.
The low-carb, high fat diet has been at the center of controversy among some of Hollywood's biggest names, including celebrity trainer Jillian Michaels. She got into hot water with television personalities Al Roker and Andy Cohen after she publicly slammed the diet and called it a form of "starving yourselves."
What do you think of Brianna and Ryan's slim down? Let us know in the comments.