"In my mind, I'm like, I'm going there to do the healthy thing, but actually you're supposed to eliminate all of the things before you get there," Jessica Alba said

Jessica Alba didn't follow all the rules when it came to preparing for a recent detox retreat. 

During an in-studio appearance on The Tonight Show Starring Jimmy Fallon last week, the actress and Honest Company founder, 40, talked about a health retreat she went on last year that got off to a bit of a rough start. 

"It was a vegan hiking detox situation," she said. "In my mind, I'm like, I'm going there to do the healthy thing, but actually you're supposed to eliminate all of the things before you get there."

"So they're like, 'For a month you should stop drinking alcohol,' " she said, joking that the night before she left, "I was like, 'How many margaritas?' "

Part of the preparation also involved eliminating meat from her diet, which she also didn't do. "I was downing tacos that morning with all the things on it," she said.

When it came to hiking, Alba said that she also didn't quite follow all of the pre-retreat rules. "You're supposed to walk for 6 miles a day, build yourself up," she said, admitting that she did "none of it" before getting there.

"Who has time for that?" she asked.

Consequently, Alba said that the first day on the trails was very difficult.

"Our first day we're halfway up, we're like, 'We don't know if we can do this anymore,'" she said, noting that the group actually got lapped by a group of "80- to 90-year-old senior citizens." 

"We're dying, huffing and puffing," she said, noting that in comparison, "they went to the top and came back down and we still hadn't made it up."

Overall, Alba described the day as "one of those moments when you're like, I might be failing at this. Whatever this is, it might not be my thing."

Jessica Alba
Jessica Alba
| Credit: Phillip Faraone/Getty

Alba had previously posted about going on the health retreat with her friend, Baby2Baby founder Kelly Sawyer, and recapped what she got out of the experience on Instagram.

"So I'm a vegan hiker now...jk," she quipped after completing the health retreat last year. "We went on all the hikes, ate bomb vegan food, got our fitness on and are now ready to plunge back to reality with new healthy habits and tips on how to incorporate wellness into our day to day."

"Thanks to @theranchmalibu I slept 8 hours a night, lowered my cholesterol, increased my lean muscle mass and feel rejuvenated and ready to take on the rest of this year with a healthier and happier mindset," she added.

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In a January YouTube video with Sawyer, the friends said that while they haven't necessarily been following the rules of the retreat at home, they did walk away with some valuable wellness tools.  

"If you can, get off of social media. Try it for five days," Alba said, explaining that people can use that time for breathing exercises or even yoga.  

"Take a walk ... find a great podcast and some bushes to go pee pee in," she joked. "In five days you can actually make a big difference so that's really cool."