One of the hottest therapy styles is scientifically shaky — so why does it seem to work?

Your Mileage May Vary is an advice column offering you a unique framework for thinking through your moral dilemmas. It’s based on value pluralism — the idea that each of us has multiple values that are equally valid but that often conflict with each other. To submit a question, fill out this anonymous form. Here’s this week’s question from a reader, condensed and edited for clarity:

What’s going on with Internal Family Systems therapy? It looks like IFS is becoming really popular, an increasing number of my friends are trying it, and mostly they report extremely positive experiences. But as far as I can tell, the evidence base for this kind of therapy is thin. A professional therapist I know with a PhD in psychology hadn’t even heard of it. I asked a chatbot to rank the top 10 evidence-based therapies and IFS didn’t even make the list.

So, I’m confused. Should I be trying to dissuade my friends from going to this kind of therapy? Or am I the one who’s missing something, and maybe I should be trying IFS myself?

There’s a mantra in IFS: Inside us, there are “no bad parts.” That may well be true of us, but I don’t think it’s true of IFS itself. This is a type of therapy that has a lot going for it, but it also has some parts that should absolutely make you skeptical.

Here’s a basic primer for the uninitiated: IFS was developed in the 1980s by therapist Richard Schwartz. Inspired by family systems therapy, he argued that just as a family is made up of members who form alliances, get into conflicts, and protect each other in patterned ways — so too is your mind. You’re not a single unified self; you’re a collection of “parts,” each with its own agenda. To understand yourself, you have to understand the dynamics between these internal “family members.”

Schwartz says your parts fall into a few categories. “Exiles” are wounded parts that carry pain and shame from when you were younger. “Managers” are protectors that try to prevent those painful exiles from surfacing — for example, through perfectionism. “Firefighters” are like the emergency response team that jumps into action when painful exiles break through anyway; they’ll use drinking, bingeing, or numbing out to protect you from the fiery, difficult feelings.

And finally, there’s “Self” — note the capital S — which is your supposed true essence, undamaged by trauma, always waiting for you underneath everything else. Your Self is characterized by calm, curiosity, compassion, and clarity. If you can access it, you can more easily build trusting relationships with all your parts, understand why they developed the coping mechanisms they did, and gradually help them release the maladaptive ones so you can live a healthier life.

Okay. Got all that? Now, here’s what I think is really going on.

There’s a lot people like about the IFS model — and with good reason. Let’s start with the core idea that your mind is not a single unified thing. That is both very intuitive and very scientifically true. You can tell it’s intuitive because we all commonly say things like “a part of me wants X, but a part of me wants Y,” or “I’m of two minds about that.” We have a natural sense that we each contain multitudes. And that’s because, well, we do! If you’ve ever taken a psychology or neuroscience class, you know that the brain isn’t a single command center — it’s a collection of systems that evolved at different times for different purposes, and they don’t always agree.

IFS’s acknowledgement of multiplicity is especially refreshing because Western philosophy has spent centuries trying to convince us that we humans are “the rational animal” — that rationality and cool logic are at the center of what it means to be human. In other words, there’s a “real you,” that real you is rational, and if you sometimes engage in illogical behavior, that’s just because passions are clouding your core judgment.

But the brain isn’t actually organized that way. It’s not a unified rational self. Your prefrontal cortex is not more “you” than your amygdala — they’re both you, pulling in different directions. And by acknowledging that we’re not fully rational beings, IFS frees us up from the expectation that we should be — a feature that bedevils other forms of therapy, like Cognitive Behavioral Therapy. CBT is based on the idea that we can catch our automatic thoughts and assumptions, check to see if they’re true, and simply change them if not. By consciously and logically adjusting our thoughts, we can, the thinking goes, transform how we feel about things.

This idea of a rational self in the driver’s seat sure offers a nice sense of control — and it works to a degree (CBT has a strong evidence base when it comes to treating conditions like depression and anxiety). But you can’t logic your way out of everything. Pretending that you can can be counterproductive. It can also make you feel ashamed: If you don’t manage to get your moods and reactions under rational control, it feels like you’ve got nobody to blame but your one and only self.

By contrast, IFS insists that even though some parts of you may act in misguided ways, they’re just trying their best to protect you. And that brings us to what is, for my money, the number one thing drawing people to IFS: This modality, and particularly the catchphrase “no bad parts,” gives people a rubric for tapping into self-compassion rather than self-judgment. For anyone with a loud inner critic, that is a huge deal.

When we see ourselves behaving maladaptively — whether it’s staying up late doomscrolling or drinking way too much — it’s really easy to hate ourselves for it. We think: I know that’s not a smart thing to do, but I did it anyway — what’s wrong with me? I’m such a screw-up! It’s incredibly helpful to instead be able to say: This is coming from a part of me that’s trying to protect me in some way, and even though it’s not going about it very well, I know the intentions are good.

So it doesn’t surprise me that so many people are flocking to IFS. It’s got some genuinely positive aspects — and it doesn’t hurt that movies like Inside Out helped popularize the idea that we’re all made up of lots of little parts!

But holy hell are there also some problematic aspects to IFS.

For one thing, let’s talk about the evidence base. There is…very little of it. Randomized controlled trials are the gold standard of medical evidence, and so far not a single one has been done on IFS as a treatment for a psychiatric disorder. As an investigation in The Cut noted last year, the strongest evidence for IFS, according to Schwartz, comes from a small 2013 study he co-wrote in which rheumatoid arthritis patients undergoing the therapy reported, on average, improved joint pain, reduced depressive symptoms, and more self-compassion several months later.

And yet IFS has been used in the treatment of all sorts of things — sometimes to patients’ detriment. Some people with eating disorders have gotten sicker, The Cut reported, as their IFS treatment focused on dredging up harrowing memories rather than stabilizing them. And some people developed “memories” of being abused by their parents, only to later allege that those were false memories introduced in the course of IFS therapy.

Experts have also begun warning that encouraging a client to play out conversations between their parts can be dangerous if the client doesn’t have a firm grasp on reality. “Our concern is that encouraging splitting of the self into parts for those who struggle with reality testing might be disorganizing,” wrote psychologist Lisa Brownstone and co-authors in a paper last year.

Even for very high-functioning clients, there’s a feature of IFS therapy that risks leading them further away from what’s real. Tell an IFS therapist that you’re skeptical about some aspect of the therapy, and too often the therapist will say something like: Oh, that’s your skeptical part talking. They may invite that part to express its thoughts, but you’re still expected to buy the premise that your unease is coming from some part that’s not to be fully trusted.

When any resistance tends to be interpreted as just another fearful part of you acting up, the therapeutic logic you end up with is a tight, self-confirming loop — one that makes it harder for you to challenge your therapist’s depiction of reality, even if it seems off to you.

Likewise with the idea (fundamental to IFS) that your feelings can be located in specific parts of the body. If you tell an IFS therapist about an anxiety or a nagging doubt, they’ll likely ask you where you can feel it in your body. Many people secretly feel…nothing. But it’s Bessel van der Kolk’s world, and we’re all just living in it: So popular is the idea that “the body keeps the score,” that people sometimes feel implicit pressure to imagine they can locate an emotional pain somewhere physical.

One of my colleagues confessed to me that when he’s been asked this, “all I can think of is ‘my shoulders’…because I have bad posture and have a desk job”! But once you’ve imagined that the nagging doubt lives in your shoulders, and you can feel the therapist waiting for your answer to this purportedly profound question, what do you do? You go for the first thing that comes to mind, and you say “my shoulders.”

If an individual walks away from a therapy session like this and feels better, I’m glad for them. But when IFS is being held up as a treatment for very serious conditions like depression and addiction, it really matters for the underlying science to be right.

That brings us to another issue: One of the core premises of IFS — the idea of the Self — is just not based on evidence. Ironically, for all its insistence that we are not unitary creatures, IFS does posit that underneath all our parts there is a unitary essence.

Believing that we each have a wise inner self is fine if you hold the idea lightly, as a kind of metaphor. But some IFS therapists talk about it way too literally.

When I tried IFS, I found this disorienting. Asked to connect with my Self, I remembered a day when I was 11 years old, singing joyously from the bleachers in my neighborhood park. Was that my one true Self? I didn’t actually believe it was — it seemed more like one version of me, a version I like and want to cultivate more. But it was so clear that I was expected to identify this as Self that I played along.

This wasn’t great, both because I felt epistemically wronged (I know the one true Self is not a thing), and because it would’ve actually been more empowering if I’d just been told: “No, this isn’t the essential you, buried deep down within and therefore sometimes accessible but sometimes not. It’s one possible you among many, and if you’d like to lean into it, you can choose to do that. And you can do that at any moment, because this is about your agency — not some preexisting metaphysical essence.”

Finally, while we’re talking about metaphysics, I need to mention the demons.

Yes, you read that right. No, I don’t mean allegorical demons.

Some leading figures in IFS, like the therapist and author Robert Falconer, believe that people sometimes become possessed by literal demons — though they call them “Unattached Burdens.” Last year, Falconer wrote a book about these malevolent beings and how to exorcise them, and Schwartz wrote the foreword. The journalist and researcher Jules Evans argues there’s a significant risk that by talking to clients about these supposed demons, IFS therapists will end up actually implanting a belief in demons into their clients — which could terrify some clients and actually worsen their mental health. The power of suggestion is not to be underestimated.

So, should you try to get your friends to stop going to IFS therapy, even if they say they’re having extremely positive experiences? It depends. If they suffer from a serious condition — an eating disorder, a history of abuse or trauma — then I do think it’s good to make them aware of the problems with IFS. If their issues are more run-of-the-mill (think: someone who just doesn’t get along great with their mom), then IFS might be helping them overall, even in spite of some of IFS’s own features. In that case, you don’t necessarily have to rush to ring the alarm, but I would periodically check in with them to make sure they’re maintaining the ability to think critically about their experience.

And as for whether you should try IFS yourself? I wouldn’t recommend starting on that path. I suspect you can reap a lot of the benefits of IFS without incurring its problematic metaphysical baggage. If, as I believe, one of the key advantages of IFS is that it helps people cultivate self-compassion, why not cut out the IFS middleman and go straight to the source by taking a self-compassion class?

A few years ago, I tried IFS therapy and, separately, an eight-week self-compassion course run by the nonprofit Center for Mindful Self-Compassion. I benefited a bit from the former, but I felt like it actually required me to push away some parts of myself. Meanwhile, I gained hugely from the latter, and I didn’t feel like it asked me to leave my critical thinking at the door.