So she did a pre-wedding diet that got her in perfect shape for the big day!
She went vegan for two weeks!
Jess has had some practice at giving up all animal products before though. As we reported last year, the 33-year-old cooked a vegan Thanksgiving for her hubby, Eric Johnson, who has been eating healthy since he left the NFL!
A source close to the pop star said:
"Jessica did a vegan diet for about two weeks leading up to the wedding.”
The bride also boosted her energy with several B12 shots leading up to the ceremony.
And in order to get her skin to glow, Miz Simpson also got a sugar dermabrasion before her big day!
Well, that’s still vegan so, scrub away, Jessica!