SEOUL — Appointment day was finally here. The parents had waited for a month to see the renowned psychiatrist in South Korea about their child’s issues. They entered the room, the doctor arrived, and the door closed.

Then the teleprompters turned on, the cameras started rolling, and the producer shouted, “Action!”

So began the taping of “My Golden Kids,” one of the most popular reality shows in South Korea. Reigning over the episode was Dr. Oh Eun-young, a specialist in child and adolescent psychiatry who has been called the “god of parenting.”

Her mantra: “There is no problem child, only problems in parenting.”

In a country where celebrity is often personified by young megastars churned out by an exacting entertainment industry, Dr. Oh, 57, occupies a singular cultural place. She draws millions of viewers on television and the internet, dispensing advice on parenting and marriage.

Through a portfolio of shows — and books, videos and lectures — she has redefined therapy for Koreans, blown up the traditionally private relationship between doctor and patient and introduced the nation to accessible vocabulary on mental health issues.

“She is the mother that you wish that you would have had in your childhood,” said Dr. Yesie Yoon, a Korean American psychiatrist in New York who grew up watching Dr. Oh’s shows. “People really put their personal feelings toward popular figures in the media. And I feel like she’s serving a kind of good mother role to a lot of Korean people.”

Her success is all the more notable in a country where taboos about seeking mental health treatment have deep roots and getting therapy has traditionally been a furtive enterprise.

South Koreans attest to Dr. Oh’s role in destigmatizing psychiatric treatment, and the fact that some are willing to share their struggles on her shows is a watershed cultural moment. Practitioners in Dr. Oh’s field say it is becoming easier to persuade South Koreans to get therapy or take medication.

In South Korea, about one in four adults has reported having a mental disorder in his or her lifetime, with only one in 55 receiving treatment in 2021, according to the National Mental Health Center. (One in five American adults received mental health treatment in 2020, according to the Centers for Disease Control and Prevention.) South Korea has among the world’s highest suicide rates; it was the fifth leading cause of death in 2020, the government says. Among people in their 20s, it accounted for 54 percent of deaths.

When Dr. Oh started her career as a medical doctor in 1996, many South Koreans associated mental illness with weakness, she said in an interview at a counseling center in the wealthy Seoul district of Gangnam. Some even believed that people could become mentally ill from studying psychiatry. Over the years, those attitudes have transformed.

“Compared to when I took my first steps as a doctor,” she said, “more people have realized that talking to a psychiatrist is something helpful — not something embarrassing at all.”

Dr. Yang Soyeong, a psychiatrist practicing in Seoul, agreed: “Parents can be afraid of having their mistakes pointed out by a psychiatrist. But because Dr. Oh does that so gently on television, I think that has lowered people’s apprehension for visiting the clinic.”

The United States has long made stars out of one-name medical personalities like Dr. Phil and Dr. Oz, who have drawn criticism for their tactics. Dr. Oh’s celebrity has also spilled out of the medical arena. In Seoul, a life-size cutout of her stands in front of a mobile phone dealership advertising the carrier’s family plans. She appears in TV commercials for a health insurance company.

Dr. Oh, who runs one hospital and four counseling centers, has been using TV as a therapeutic platform since 2005, when she started her broadcast career giving lectures about childhood developmental disorders.

On “My Child Has Changed,” which aired from 2005 to 2015, each episode was dedicated to a family’s problems. Dr. Oh entered their homes for counseling sessions, and the takeaway from many episodes was that a lot of children’s problems were caused by parental abuse, lack of understanding or negligence.

In a signature flourish of the show, Dr. Oh would dispose of every object the parents used to beat their children — back scratchers, umbrellas, shoehorns, broken chair legs.

When “My Golden Kids” launched in 2020, the pandemic, with its social restrictions, was forcing people to confront loved ones’ problems full on. Rather than visiting herself, Dr. Oh now sends a camera crew into homes to record what transpires; clips are aired when families discuss issues in the studio.

The problems shown have run the gamut: A 9-year-old yelling at his mother, a 5-year-old self-harming, a 12-year-old stealing from his mother, a 14-year-old having unexplained, chronic vomiting.

Even with a family’s consent, the in-home cameras can feel highly intrusive. But giving a doctor the chance to assess family interactions in real-life settings, not the confines of a psychiatrist’s office, has diagnostic advantages, experts say.

“It’s a child psychiatrist’s dream,” said Dr. Yoon, the New York psychiatrist. “In my clinic, I only address and discuss the things that they bring to me. I may ask questions to dig deeper that they may not answer, and they may not answer truthfully.”

The show illustrates how much work the parents do in following through with the doctor’s advice. It also shows how change can take time, and how old issues can resurface.

Since “My Golden Kids” began, Dr. Oh has expanded her TV empire to include “Oh Eun-young’s Report: Marriage Hell,” in which she counsels couples; and “Dr. Oh’s Golden Clinic,” in which she advises individuals. She says she has a plan to tackle the country’s low birthrate by easing people’s fear of having children. She also hopes to feature more Korean families who live abroad and encounter cultural and language barriers.

Dr. Oh was born premature, and she said the doctors were not sure she would survive. Until she was about 2, she was smaller than her peers and had a “difficult temperament”: picky with food, often sick and crying every night. She attributes her comfort with herself as an adult to her parents, saying she had “received a lot of love from them and felt understood by them.”

She received bachelor’s and master’s degrees from Yonsei University’s College of Medicine, and a medical degree from Korea University’s College of Medicine. She married a doctor, and their son is in the military.

“We were all someone’s children at some point,” she said. “The point isn’t to blame parents for every problem but to emphasize that they are incredibly important figures in children’s lives.”

At a recent taping of “My Golden Kids,” a panel of comedians and celebrities appeared. They and Dr. Oh greeted the parents of a child who had refused to attend school for months. Video of the family’s home life was shown. The doctor then shared her recommendations.

She has critics. Lee Yoon-kyoung, 51, an activist for education reform and parental rights and the mother of two high school-age sons, worries that Dr. Oh’s celebrity might lead viewers to consider her words as gospel when there might be multiple interpretations of the same behavior.

“Of course, we acknowledge her expertise,” Ms. Lee said, “but some parents get a bit uncomfortable when people deem her opinions unconditionally true, as if her words were divine.”

Some viewers have questioned the wisdom, as well as the privacy implications, of putting yelling, hitting families on television. On “My Golden Kids,” Dr. Oh does not explicitly identify the children, but faces are not obscured, and parents state their own names and call their children by name.

Videos of episodes have been uploaded to YouTube, generating humiliating comments about the families. Comments have since been turned off. But some parents and mental health professionals, noting that the internet is forever, have demanded the show blur faces.

Dr. Oh says blurring could make it harder for people to empathize, inviting more abuse. Viewers, she said, should consider the problems televised as all part of the human experience. “The main reason I do these shows is that understanding children is the starting point of understanding people,” she said.

Ban Su-jin, a 42-year-old mother of three from Incheon, had privacy concerns when she appeared on “My Golden Kids” in 2020 to consult about a son who feared leaving the house.

“My husband was worried that my son’s friends would make fun of him for having this problem,” she said. But they agreed it was “worth risking anything.”

After the taping, she said, her son’s anxiety improved drastically. The episode drew some negative messages, Ms. Ban said, but also encouragement from friends and neighbors.

“The episode,” she said, “helped them understand how much pain my son had borne.”