Last year brought us Morgan Neville’s winning documentary “Won’t You Be My Neighbor?” about beloved children’s TV personality Fred Rogers. Now we have a biographical celebration of another unlikely television host, Ruth Westheimer, the diminutive sex therapist who became a media sensation in the eighties and nineties with her straight talk about matters that until then were thought taboo on the tube. Boy, did she prove the arbiters of taste wrong.

Ryan White’s affectionate “Ask Dr. Ruth” covers Westheimer’s media career from 1980, when her late-night radio show “Sexually Speaking” first appeared on a New York station at midnight on Sundays. It built into the most popular radio show in the area and was picked up by NBC, leading to her move into television in 1984. The film includes a considerable number of clips from her programs, as well as comments from station personnel who worked with her in the business; it then follows the celebrity that built up around her not only through broadcasting but also via her books and appearances in commercials, sitcoms and even features.

There’s a genial quality to the film’s evocation of Westheimer’s public persona, but also an emphasis on the serious undercurrent that always marked her arguments. Not only did she take the questions put to her by ordinary folks seriously and give frank (and often curt) responses to them, White indicates, but she confronted controversial issues like abortion and AIDS without apology or queasiness. She led the way to opening discussion of subjects that before were only whispered about.

White, cameraman David Paul Jacobson and editor Helen Kearns do a good job getting across the feel and trajectory of Westheimer’s career, but that’s only part of the portrait their film draws, and in many respects the other portion is more interesting. That’s the broader autobiography, more personal in nature, that “Ask Dr. Ruth” offers.

Born in Frankfort in 1928, as a child Karola Ruth Siegel, along with her loving family, felt the effect of the Nazi rise at an early age. Her father was taken away in 1938, and the following year her mother and grandmother put her on a train for transport to an orphanage in neutral Switzerland. Using Westheimer’s own recollections, archival photographs and footage, and animated segments, White evokes her experiences during the war, as letters from her parents stopped arriving; later footage will later show her investigating the records to learn of their fate.

But her years in the orphanage had another side, as the film shows when Westheimer visits her childhood boyfriend Walter, and reminiscences with him about the kisses they shared, but also how he snuck into her room at night to teach her what he had learned in the classes from which she was, as a girl, excluded. It’s a lovely sequence, buoyed by Westheimer’s endless joviality.

The remainder of the autobiographical material—from her post-war training as an Israeli sniper (which ended in serious injury), through her three marriages and her late-in-life education (she didn’t get her doctorate until she was in her forties), to the present, when she spends time with her son, daughter and grandchildren—doesn’t possess the poignancy of those childhood memories (although the death of her third husband reinforces the sense of loss), but it’s well done, with Westheimer’s recollections providing the words. The film closes with her ninetieth birthday celebration, when the still-spry icon of feminism, who nonetheless rejects the label of feminist when her granddaughter tries to press it upon her, happily listens to speakers singing her praises.

You’re likely to agree with them as the film ends. One can point out that it is remarkably parsimonious when it comes to giving critics an opportunity to offer any negative views of her influence—archival footage of one colleague in the field suggesting that her habit of offering quick, off-the-cuff answers is reckless is about all there is. Still, Westheimer’s generally high spirits and her zest for life are infectious, and “Ask Dr. Ruth” evokes them without overlooking the losses she has suffered.

In the end, White succeeds in providing a sympathetic portrait both public and personal, covering not only Dr. Ruth’s career but her life as a whole. And though Westheimer spoke to a very different audience than Fred Rogers, both of them represented an effort to help their listeners become more self-aware and considerate of others, and both showed how television can be employed to educate as well as entertain.