Over the decades, and especially since the pandemic, the stigma of therapy has faded. It has come to be perceived as a form of important self-care, almost like a gym membership — normalized as a routine, healthful commitment, and clearly worth the many hours and sizable amounts of money invested. In 2021, 42 million adults in the United States sought mental-health care of one form or another, up from 27 million in 2002. Increasingly, Americans have bought into the idea that therapy is one way they can reliably and significantly better their lives.

As I recently considered, once again, entering therapy, this time to adjust to some major life transitions, I tried to pinpoint how exactly it had (or had not) helped me in the past. That train of thought led me to wonder what research actually reveals about how effective talk therapy is in improving mental health.

Occasionally I tried to raise the question with friends who were in therapy themselves, but they often seemed intent on changing the subject or even responded with a little hostility. I sensed that simply introducing the issue of research findings struck them as either threatening or irrelevant. What did some study matter in the face of the intangibles that enhanced their lives — a flash of insight, a new understanding of an irrational anger, a fresh recognition of another’s point of view? I, too, have no doubt that therapy can change people’s lives, and yet I still wanted to know how reliably it offers actual relief from suffering. Does therapy resolve the symptoms that cause so much pain — the feeling of dread in people who deal with anxiety, or insomnia in people who are depressed? Does the talking cure, in fact, cure? And if it does, how well?

Sigmund Freud, the brilliant if dogmatic father of psychoanalysis, was famously uninterested in submitting his innovation to formal research, which he seemed to consider mere bean-counting in the face of his cerebral excavations of the unconscious. Presented with encouraging research that did emerge, Freud responded that he did not “put much value on these confirmations because the wealth of reliable observations on which these assertions rest make them independent of experimental verification.” A certain skepticism of the scientific method could be found in psychoanalytic circles well into the late 20th century, says Andrew Gerber, the president and medical director of a psychiatric treatment center in New Canaan, Conn., who pursued the use of neuroimaging to research the efficacy of therapy. “At my graduation from psychoanalytic training, a supervising analyst said to me, ‘Your analysis will cure you of the need to do research.’”

Over time, formal psychoanalysis has largely given way to less-​libido-focused talk therapies, including psychodynamic therapy, a shorter-term practice that also focuses on habits and defenses developed earlier in life, and cognitive-behavioral therapy, which helps people learn to replace negative thought patterns with more positive ones. Hundreds of clinical trials have now been conducted on various forms of talk therapy, and on the whole, the vast body of research is quite clear: Talk therapy works, which is to say that people who undergo therapy have a higher chance of improving their mental health than those who do not.