Depressed? Ask Your Doctor if a Placebo is Right for You

Psychotherapy as we know it has been around for about a century, and has been continually refined since.

So why do placebo treatments perform almost equally as well? What is it that actually makes therapy so effective at treating mental illness — and what could a placebo share in common?

In the 1980s, the National Institute of Mental Health launched the Treatment of Depression Collaborative Research Program, a large-scale randomized control trial that eventually formed the scientific basis for the belief that therapy is effective. The study showed that interpersonal therapy and cognitive behavioral therapy worked equivalently well to antidepressants for reducing the symptoms of depression.

In the following three decades, psychotherapy — especially short-term, manualized therapy of the kind tested in the study — has exploded in popularity as a front-line treatment for mental illness.

Still, there’s more to the story.

A closer look at the NIMH-TDCRP’s results reveals a curious phenomenon: The therapies and antidepressants barely outperform placebo treatment. On the 54 point Hamilton Depression Rating Scale, CBT does, on average, 1.2 points better than a sugar pill combined with weekly meetings with a psychiatrist.

This is not to say that therapy didn’t work — in all treatment groups, depression symptoms were reduced from severe to mild. Rather, it is to say that there was nothing specifically effective about the psychotherapies: A sugar pill and weekly meetings with a psychiatrist to discuss the effects of the ‘treatment’ were also comparably effective.

So why is a sugar pill performing on the level of state of the art therapy and antidepressants? The most plausible answer goes deeper than what pharmaceutical companies describe as “chemical imbalances in the brain.” The only explanation for the efficacy of the sugar pill lies beyond the pill — in the psychiatrist’s caring relationship with the patient.

In meta-analysis after meta-analysis, almost every (vastly different) approach to psychotherapy is similarly effective at treating depression. This begs the question: Are there certain factors that all therapies have in common that make them effective? Most centrally, if the theory you choose doesn’t matter for outcomes, then what makes therapy work?

This phenomenon, known as the “dodo-bird verdict,” has stoked controversy in the field for almost a century. It dates back to the 1930s, when American psychologist Saul Rosenzweig mused that what might matter for the efficacy of therapy is not the philosophy, but the human relationship beneath it all.

Arguably the foremost modern theorist of this phenomenon, Bruce Wampold, proposes that therapy is a special case of a “social healing practice,” and is thus a specific practice of the basic human act of taking care of each other. In this view, therapeutic efficacy is based on three key things: the real relationship between the therapist and the patient, the plausible explanation of symptoms, and the encouragement of health promoting actions.

With a model like this, the sugar pill’s effects don’t seem so ridiculous. Though the patient is taking medication with virtually no active ingredients, they are still consistently meeting with a trusted psychiatrist, both parties expect and believe that the pills treat depression, and the psychiatrist continually encourages behavior that improves wellbeing.

In the same way, because all therapies are built upon a real relationship, have reasonable narratives, and promote healthy behavior, their rates of success are bound to be similar.

The consequences of this being true — and, in my view, it really seems to be the most plausible explanation — would have massive public health implications. It isn’t that therapy is no better than a placebo. It’s that relationships of care and support are the most fundamental component of psychological well-being, whether or not they’re embedded within a medical system.

Our best hope of dealing with this era’s mental health crisis is through the realization that the things that make psychotherapy effective are not limited to psychotherapy at all. Mentoring, supporting, and taking care of each other is as old as human history, and though it’s not a pharmaceutical, it’s no placebo.

Suhaas M. Bhat ’23-’24 is a double concentrator in Social Studies and Physics in Mather House. His column, “Demystifying Therapy,” runs on alternate Wednesdays.