Techniques that encourage positive thinking could help people cope with mild depression, a new paper suggests.
Researchers from the University of California and Duke University reviewed previous studies that show writing letters of gratitude, counting one's blessings, practicing optimism and performing acts of kindness help people who are not depressed or mildly depressed.
For example, one study cited by the researchers included 51 positive thinking interventions done with depressed and nondepressed patients, and found that these techniques worked almost as well as cognitive therapy in some respects. Another study of 411 patients with mild depression found that a week of activities designed to enhance well-being improved their symptoms, and the effects lasted longer than the placebo treatment.
If these techniques, which the researchers call positive activity interactions (PAIs), work for people who have more severe depression, they could prove a cost-effective way to augment more traditional treatments such as medication and cognitive behavior therapy, the researchers said.
However, other experts are skeptical of the findings, saying they neglect to take the complexity of depression into account.
The researchers developed positive activity interactions by looking at the types of thoughts distinguish happy people from people with depression.
"These are the types of things that people who are happy have been practicing anyway," said study researcher Kristin Layous, a doctoral student at the University of California, Riverside. "We started taking some of those thoughts and behaviors and packaging them into these interventions."
The article is published in the August issue of The Journal of Alternative and Complementary Medicine.
Filling a treatment gap
If future studies find that positive activity interactions work well for people with clinical depression, they could help those who either don't get enough treatment or don't get any treatment at all.
"We estimate that about 70 percent of reported cases don't receive the recommended level of treatment," Layous said. "It's simply not available to everybody."
The researchers said they aren't discounting medical treatments, but added that drugs don't work for everybody. Antidepressants can also have serious side effects.
Cognitive behavior therapy, too, has limits, the researchers said. It's time-consuming and expensive for some people to meet with a therapist for the recommended number of sessions.
Further, while cognitive behavior therapy addresses certain aspects of depression, positive activity interaction might address others, Layous said. "In its purest form, cognitive behavior therapy is designed to dispute negative thoughts, though it is not inherently trying to replace them with positive thoughts," she said.
In studies of healthy and mildly depressed people, "after prompting them to do these activities, we have found increases in their well-being," Layous told MyHealthNewsDaily.
Positive thinking lights up the brain
The study authors hypothesized that activities that promote positive thinking might affect parts of the brain that control depression. Some studies show that the brain's reward circuitry lights up when people practice positive thinking, they said.
"We think working on this reward-related circuitry targets a different part of the brain than drug therapy," Layous said. "Maybe together, they could help people more than any one could help apart. It could serve as a really good complement to what is already being done."
The study is based on the theories of positive psychology, a field of research that focuses on analyzing how people thrive, as opposed to analyzing psychological disorders.
Other psychology experts are critical of these theories.
While the study authors' critiques of mainstream treatments for depression are valid, positive activity interventions are likely not the answer to treating clinical depression, said Dr. Richard Sloan, a professor of behavior medicine at Columbia University Medical Center.
"Life is hard, and I don't think you can smile your way out of depression," Sloan said. "The interventions are, essentially, count your blessings every day and you'll get better. [Depression] is more complex than the proponents of positive psychology would suggest."
Layous agreed that the evidence for the effects of positive thinking and depression is far from conclusive. "We have made advances on mildly depressed populations and nondepressed populations," she said. "And, we think the treatment is promising in clinically depressed populations as well, but more research is needed."
In a world of "infinite research resources and infinite time," more study might be warranted, Sloan said. "But neither one of those is true," he said. "Devoting resources to something that has a limited effect … strikes me as unwise."
Pass it on: Activities that promote positive thinking could complement medication and cognitive behavior therapy in people with clinical depression, but more research is needed.
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