Do affirmations work? The honest answer is yes, a little, for some people, and not in the way most pages promise. Anything shorter than that is either selling something or repeating a headline nobody read past.
Do affirmations work, in one paragraph
A large review published in 2025 pooled 129 tests across 67 studies and more than 17,700 participants. Self-perception and wellbeing both improved measurably. The size of that improvement was small, and the participants were mostly students. Nothing in the research supports a promise about your circumstances, your health or your income.
What the research actually measured
Three studies carry most of the weight in this topic. They looked at different things, and conflating them is how the internet ended up so confident.
| Study | What it tested | What it found |
|---|---|---|
| Zhang and colleagues, 2025 | 129 tests of values-based self-affirmation exercises | A real effect on self-perception and wellbeing. Small. Mostly students, mostly in the United States. |
| Wood and colleagues, 2009 | Repeating a single positive statement about yourself | People with high self-esteem felt slightly better. People with low self-esteem felt worse than the control group. |
| Cohen and Sherman, 2014 | A review of what self-affirmation means in psychology | The tested exercise is reflecting on a personal value in writing, not repeating a phrase. |
Why the honest answer has two halves
Almost every confident article on this subject rests on a swap. Researchers use the term self-affirmation for a writing exercise: you pick a value you care about and spend a few minutes explaining why it matters to you. That's the thing with a pile of evidence behind it.
The popular practice is different. You choose a sentence, put it somewhere visible, and read it when a hard moment arrives. Reasonable, widespread, and studied far less often.
Both get called affirmations. So a study on the first gets reported as proof of the second, and the gap between them disappears somewhere between the journal and the headline.
How do affirmations work when they do
No mechanism has been established, and pages claiming one are usually inventing neuroscience. What the research suggests is modest and plausible.
- Reminding yourself of something you value seems to soften a threat to one part of your life. A bad review at work stays a bad review rather than a verdict on you.
- A prepared sentence interrupts a familiar loop. You answer the thought instead of following it.
- Choosing a line in advance means the decision gets made when you're calm rather than at the worst moment.
None of that changes a situation. It changes what you do in the next ten minutes, and sometimes that's the whole difference.
What a small effect means in practice
Small is doing a lot of work in that sentence, and it's worth unpacking, because it's the word every enthusiastic summary drops.
A small average effect means the groups overlap heavily. Plenty of people in the affirmation condition did worse than plenty of people in the control condition. The averages differ; the individual outcomes scatter across each other.
It also means the effect is easy to swamp. A difficult week, a poor night's sleep, a genuinely bad situation: any of those moves the needle further than the exercise does. That isn't a reason to skip it. It's a reason to keep expectations the size of the finding.
Set it beside the things that reliably shift mood over weeks. Sleep, exercise, time with people who like you. Affirmations sit well below all of those. They're cheap and quick, and that's a fair argument for them. Powerful isn't.
Who they don't work for
This part rarely makes the listicles. A 2009 experiment split people by self-esteem before asking them to repeat a flattering statement, then measured mood.
The split mattered enormously. Confident participants came out marginally happier. The less confident group ended up below the people who had said nothing at all, reversing exactly what the advice promises them.
A third condition asked participants to weigh the statement against the ways it fell short. Allowing that doubt produced better results than insisting on the flattering reading.
So if a line has ever made you feel worse, you weren't doing it wrong. You ran into a documented effect, and the answer is a smaller claim rather than more repetition.
What would make the answer clearer
The gaps in this evidence are specific, and naming them is more useful than another confident summary.
Most participants have been university students, recruited because universities are where the researchers work. Students are younger, healthier and better resourced than the general population, and findings from that group travel badly.
Follow-up periods are short. Days and weeks, rarely months. Nobody can tell you what a year of this does, because nobody has properly looked.
And the popular version, one chosen line used at a chosen moment, has barely been tested on its own terms. Until it is, honest pages will keep hedging, and any page that doesn't hedge is guessing.
The one-minute version
- Step one
Real, small, uneven.
An average effect across groups, not a promise to you.
- Step two
Mostly a different exercise.
The evidence covers reflective writing more than repeated phrases.
- Step three
Wording decides the direction.
Overshoot and it can backfire, measurably.
What this can and cannot do
Research on this topic can tell you what happened on average to groups of mostly young, mostly American participants over days and weeks. It can't tell you what will happen to you this afternoon. Nothing here supports using a sentence in place of care for a health problem. And if low mood or anxiety has been shaping your weeks rather than your hours, that belongs with a professional rather than with a wording exercise.
Sources and further reading
These references support the research and practical guidance discussed in this article.
- Self-affirmations can boost well-being: a meta-analysis of 67 studiesZhang, Chen, Hu and Wang, American Psychologist, October 2025. Pooled 129 tests across 67 studies and more than 17,700 participants, and reported a small positive effect. The main evidence on this page.
- Positive self-statements: power for some, peril for othersWood, Perunovic and Lee, Psychological Science, 2009. Participants with low self-esteem who repeated a positive statement felt worse than those who repeated nothing. The reason this page refuses to give a blanket yes.
- The psychology of change: self-affirmation and social psychological interventionCohen and Sherman, Annual Review of Psychology, 2014. Sets out what psychologists mean by self-affirmation, which is the reason most of the research does not describe the popular practice.
