Writer/director Lorella Loftus’ new show, “My Big Fat Bahookie,” is not afraid to ask audiences to practice what it preaches. Before entering the theater, attendees are requested to fill out two sticky notes, one listing a moment of positive self-esteem and another noting an element of personal body positivity. This sort of self-reflection on the part of the audience is encouraged throughout the production, grounding the production’s zany antics in a very personalized sense of loving one’s body and one’s whole self.

“My Big Fat Bahookie,” produced by Renaissance Austin and playing at the Vortex through May 6, takes the form of the first meeting of the fictional “No More Diets Club,” a kind of hybrid between a talk show, a self-help infomercial and a 12-step meeting. The club’s founder, Marianne McGonigle (played by Loftus), is also the evening’s hostess, ushering in a variety of skits, songs, scenes, strange personalities and pre-produced video segments.

What unites these various segments into an overall variety show-style presentation is a thematic focus on body positivity and a denial of the negative messages marketed to us by the health and beauty industries. A lot of righteous rage is aimed in the direction of these industries, but the show’s method of critique is humor more than anger, satirizing and spoofing societal notions of beauty.

In addition to Loftus, “My Big Fat Bahookie” features a large cast, most of whom portray multiple characters and personalities throughout the course of the evening. Melissa Vogt and Heidi Penix stand out as the most seemingly effortless satirists, embodying a wide range of wacky characters who poke fun at diet “experts.” Mindy Rast-Keenan and Jennifer Haston also delight as less directly satirical characters whose broad-strokes character arcs tie much of the show together.

As with most variety/comedy shows of this type, “My Big Fat Bahookie” is uneven, mixing smart satire, a few touching moments and some dull bits into a loose framework that never quite coheres. Although individual parts of the show soar (particularly a pre-filmed semi/pseudo-documentary quest for properly fitting jeans featuring stage manager Suzanne Smith), the whole is less than the sum of those parts.

Where “My Big Fat Bahookie” soars highest, though, is in its blatantly personal-as-political approach to issues of beauty, body and, yes, bahookies (a Scottish slang term for one’s behind). Loftus wants the audience to leave the show feeling better about their bodies, embracing themselves with the same sense of warmth, humor and acceptance that permeates the entire show.

Though not the most cohesive of theatrical productions, “My Big Fat Bahookie” wears its heart (and other parts of its anatomy) on its sleeve, with a positive message that everyone should get behind.

“My Big Fat Bahookie”
When: 8 p.m. Wednesday-Sunday through May 6
Where: The Vortex, 2307 Manor Road
Cost: $15-$35
Information: 512-478-5282, vortexrep.org.