In the new Apple TV Plus show “Physical,” negative self-talk takes center stage.

Sheila Rubin (Rose Byrne), a 1980s Southern California housewife struggling with an eating disorder, is bombarded by cruel thoughts about herself and those around her constantly. Her inner dialogue, which is a voice-over in the show, is overwhelmingly negative. She berates herself (“You’re the only one who thinks about food this much”), insults herself (“You lazy, fat pig”), and after painful episodes of binge-eating and purging, makes empty promises to herself: “Today we will eat clean, healthy foods.”

It doesn’t stop at her body. Rubin’s thoughts bleed into other areas of her life. She often doubts her husband’s attraction to her: “Wrinkles and zits, that’s a real sexy cocktail you’re serving up.” When her friend invites her on a walk: “Don’t get sucked in. She’s a riptide. She’ll just suck you out to sea.” At a party for her husband, who is running for state assembly: “Now you’re just an overdressed … sad sack married to yesterday’s news.”

Although Sheila’s self-talk in “Physical” is extreme, a negative inner dialogue isn’t uncommon. Research has shown that negative self-talk can cause anxiety and depression, zap motivation, lead to chronic stress disorders and, in some cases, exacerbate eating disorders. It also goes beyond body image and food compulsion. Even seemingly innocuous aspects of life such as housekeeping are ripe for self-criticism and a negative feedback loop (for example, walking by a messy closet or stack of dishes and thinking some variation of “I’m such a slob,”). It can relate to careers, parenting and relationships — and it’s a challenge to change the way we speak to ourselves, experts say.

In Ethan Kross’s book “Chatter,” the psychologist discusses why the voices in our heads matter. He writes that “chatter in the form of repetitive anxious thought” can derail focused tasks, negatively impact our social lives and render us unable to address daily challenges.

“In the simplest sense,” he writes, “chatter is what happens when we zoom in close on something, inflaming our emotions. … We lose perspective.” By allowing the negative voice to narrow our view of a problem, he argues, we dwell on certain thoughts that trigger stress, anxiety and depression.

Ozlem Ayduk, a professor of psychology at University of California at Berkeley, studies emotional regulation and self-reflection. She said that negative self-talk has adverse physiological effects on the body by keeping one’s mind in a state of constant stress.

“You’re not allowing your body to recover and rest, and that chronic activation, maybe not heart-palpitating activation all the time, but not being able to let go of the stressor is basically one of the pathways all the way to cardiovascular disease,” Ayduk said.

As in Sheila’s experience in “Physical,” body image and food compulsion is a common trigger for negative self-talk. Research conducted by A. Janet Tomiyama, an associate professor of psychology at the University of California at Los Angeles, found that the extent of a person’s bias against heavier people is directly correlated to how they feel about themselves and their own bodies. “If you yourself feel bad about your body, you internalize that and have higher anti-fat attitudes,” she said, pointing out that women are particularly predisposed to engaging in negative self-talk.

This can be compounded by gender norms placed on women and traditional ideas of how women are supposed to look and act, much like the very gendered household roles Sheila and her husband fill in “Physical.”

In relationships, engaging in negative self-talk can also take away from having meaningful interpersonal interactions. If a person is busy monitoring or loathing themselves, Ayduk said, it takes away from a “mutual, constructive relational exchange.” In “Physical,” Rubin can’t let go of weight stigma and food compulsion, blinding her to the emotional anguish one of her friends is experiencing. Instead, she homes in on her friend’s weight, hyper-focused on what and how much her friend eats.

One technique to combat negative self-talk involves switching from an egocentric point of view to a distant point of view that allows one to step back and observe, as if you are someone else. Most people use the first person when they are talking to themselves, Ayduk said, but talking to yourself as if you’re talking to someone else by using your own name and third-person pronouns can help create that necessary distance between the thought and yourself.

“When the self is distanced, typically people are able to see things that are outside of their egocentric focus,” Ayduk said. “It’s kind of like you’re giving advice to a friend, and it’s a common phenomenon that we can reason about somebody else’s problem much more easily than we can about our own.”

In addition to distancing, another way to combat negative self-talk is to write it down. “Perpetual negative self-talk happens because people are trying to make sense,” Ayduk added. “Expressive writing helps because it helps you write that narrative, in this case literally, and then you put it on the shelf.” She recommends keeping a journal to write down repetitive thoughts, which can create distance.

When experiencing overwhelming negative thoughts, venting to friends, family or colleagues is often natural. Talking about negative feelings with others can help, but as Kross writes, it’s important to choose whom you go to for support carefully. In an ideal situation, different people can serve as “chatter advisers” for different problems — for example, a trusted co-worker might be the best person to consult on a professional problem while a romantic partner may be better suited for family dramas. Identifying the right sounding board can help deal with negative inner dialogue in the most productive way, rather than focusing on the emotion behind the negative event.

Research also shows that immersing yourself in nature or art can help negative self-talk subside by “involuntary shifts in attention” away from problems we are ruminating on — and toward something like a beautiful sunset or a famous painting. Rest and recharging are crucial to quieting the voices in our heads.

“The ability to divert our internal conversations away from things that are bothering us, or reframe how we’re thinking about stressful situations, likewise requires that our executive functions not be running on empty,” Kross writes.

In “Physical,” audiences can recognize how Rubin’s nonstop, stress-inducing self-talk seeps into various aspects of her life and contributes to her eating disorder, her inability to constructively communicate her needs to her husband, and the hatred she feels for her own body.

It’s a jarring reminder of the importance of self-compassion, for both our bodies and minds. Tomiyama works with mindfulness educator Diana Winston, who told her that self-compassion is one of the hardest things to teach people.

“It's easier in her experience to get people to have compassion toward others. But turning it in on yourself is really, really difficult,” Tomiyama said.

As Kross recommends, imagine you’re talking to a friend — think about the advice you would give that person, then apply it to yourself.