Kevin Smith talks rapid weight loss, loses 20 pounds in 13 days

Kevin talks rapid weight loss post sudden heart attack. (Jesse Grant/Getty Images)

Kevin Smith is coming back strong after suffering a near-fatal heart attack last month.

The celebrated filmmaker took to Twitter on Wednesday to talk with fans about how his weight loss efforts have led to an impressive improvement in a very short amount of time.

"I’m officially down 20 pounds as of this morning!" Smith tweeted. "20 pounds in 13 days & my blood pressure is amazing."

According to the "Clerks" director, he found a lot of inspiration and guidance from Penn Jillette's 2017 book "Presto!", which detailed the magician's 100-pound weight loss journey, as well as dietary nutrition researcher Ray Cronise.

"My Doc said lose 50 pounds. 20 down, 30 more to go!" Smith wrote.

The 47-year-old filmmaker also took to Instagram to show off his new jersey, which was a gift from writers of the CW series "Supergirl" and was designed by the show's storyboard artist, Jeremy Simser. The illustration on the jersey depicts a cybernetic construct housing Smith's now-healthier heart.

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"My new jersey commemorating my life & death battle with arch nemesis, The Widow-Maker!" Smith wrote, referring to the massive blockage in his left anterior descending artery which required emergency surgery on Feb. 26.

Smith said the gift accompanied a sweet note with some kind words from the writers room.

"The card read 'A crest to commemorate your big win against the deadliest of foes, the wrathful Widow-Maker. We could’ve made you the man with the Kryptonite heart, but this wasn’t your Kryptonite. We could’ve given you an Arc Reactor, but that’s the competition. And anyway, the best part about you is your heart’s always your own. Wear it on your sleeve, or in this case, smack dab in the center of your jersey. - The "Supergirl" Writers,'" Smith shared. "Thank you, my "Super" wordsmiths! I believe, in this jersey, a man can fly!"

Smith -- who lost around 90 pounds over seven years before his heart attack -- opened up on his "Hollywood Babble-On" podcast about how he's been recovering and losing weight since returning home.

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Citing Jillette's nutrition plan -- which includes eating just potatoes for two weeks before slowly integrating various other vegetables into his diet -- Smith said it's " a pretty intense program, but it’s been interesting. And of course necessary for my health and stuff. But once I get to a decent place, then I can think about eating again."

Smith also reiterated his commitment to becoming a vegetarian, which was partially inspired by his vegan daughter, Harley Quinn.

"My kid is thrilled because she’s a vegan, 'She’s like, 'Welcome home brother,'" he shared, adding that the decision "doesn’t come from a personal philosophy, this comes from an 'I have to.'"

In a funny, touching Facebook Live -- which he filmed from his hospital room at the Glendale Adventist Medical Center following his surgery -- Smith said he's going to be taking a lot of pills, including blood thinners and beta-blockers, and will have to see a cardiologist regularly in the wake of his life-threatening medical episode.

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