The Science Behind Positive Affirmations

The science is unequivocal. Positive self-talk affirmations improve our health. Let’s look at the science behind positive affirmations! And easy ways how to combat negative self-talk, so we can all be healthier & happier.

Louie Make Sense of Science
Will there be treats?

 I agree w/ Louie, because treats make me happy, too! But I want lasting, calorie-free, drug-free ideas to guard us against the inflammatory damage of stress.

This is a pretty big ask, but I’ve gathered evidence! And made a cool word cloud!

‘A sad soul can kill you quicker, far quicker than a germ.’


Medical thinkers up into the 19th century assumed that the human body was governed by the circulation of fluids, or humours.
Hx of humours
The theory of humours sought to explain individual differences in character.
These 4 primary humours, chole (bile), melanchole (black bile), sanguis (blood) & flegma (phlegm)....
...Expanded from the theory that fire, earth, water, and air were the 4 basic elements making up the universe.
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Okay, the theory of humours does have a few flaws.


Several philosophers & physicians built on the theory
& answer the question 'do positive affirmations work?'
Galen of Pergamum (AD 130–200) used the humours theory to explain differences between individuals' disposition
Galen extrapolated that passions of the mind exerted pressure on the body, thereby inducing illness or restoring health.
Renaissance doctor Levinus Lemnius recommended good company, ‘dallying and kissing’, drink and dancing – all of which, he noted, generate an emotional uplift that endures for days afterwards, visible in the face.
18th-century Scottish philosopher David Hume noted that cheerfulness is a force that is larger than the individual.
Hume observed that when a good-humoured person enters a room, ‘cheerfulness carries great merit with it, and … others enter into the same humour, and catch the sentiment, by a contagion or natural sympathy.’
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Make Sense of Science_Ian

I bet a lot of you smiled at that photo of the adorable, happy boy, proving Hume’s point.

‘Power dwells with cheerfulness.'

History doesn’t glamorize positive people. Most of us know that Socrates died by drinking hemlock, condemned to death by the people of Athens. (Although I’m not sure why he didn’t just leave.)


Not to mention the infamous melancholy associated w/ Nietzsche, Sylvia Plath, Franz Kafka, and Vincent Van Gogh.

But the cheerful David Hume, arguably the greatest philosopher the West has ever produced, is virtually unknown.


10 Great Scientists and Their Discoveries Louie
Nope. Not David Hume.

'We are shaped by our thoughts; we become what we think.'

Buddha Japan

Okay. The philosophers & physicians above used observation to draw their conclusions.

We need science to answer the question, ‘do positive affirmations work to make us healthier and happier?’

The science behind positive affirmations_Kevin
Am I David Hume? (No)

Taken from a paradoxical angle, below are many proven facts about brain physiology, which contribute to building evidence towards the science behind positive affirmations.

Self affirmation theory_positive affirmations


Depression represents the # 1 cause of disability worldwide
Depression & disability
The results of study after study validate that emotional trauma causes changes in the brain.
Emotional trauma
An emotional trauma may induce a cascade of neurobiological events that have long-lasting consequences & even altered gene expression.
PTSD brain changes
Patients with posttraumatic stress disorder (PTSD), social anxiety disorder, specific phobia, & fear conditioning consistently showed greater activity than matched comparison subjects in the amygdala & insula, structures linked to negative emotional responses.
neuroimaging of anxiety
When strong emotions are involved, millions of neurons can become more active.
In a 2016 study of survivors of a plane crash, recalling the crash increased neural activity in ‘the amygdala, medial temporal lobe, anterior & posterior midline, and visual cortex’ of the passengers.
2016 study
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On the flip side, emotionally positive thoughts cause positive changes in the brain!

Do positive affirmations work?


Positive affirmations are positive thoughts, and they cause changes in our brains too!


Candace Pert, a molecular biologist & a key figure in the discovery of the endorphin molecule, the body’s natural form of morphine once commented, “We’ve all heard about psychosomatic illness, but have you heard about psychosomatic wellness?”

Enter self-affirmation theory!

you don't say
I'm listening, and I'm not David Hume.
One of the key psychological theories behind positive affirmations is self-affirmation theory
SA Theory
The idea is that we can maintain our sense of self-integrity by telling ourselves (or affirming) what we believe in positive ways.
Self-affirmations can have lasting benefits
SA benefit study
Positive self-talk affirmations verify the adaptive adequacy of the self, & can promote positive behavior change & adaptive outcomes.
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Self-affirmation theory suggests that there are many possible ways that people can protect their self-esteem when it is under threat.

Affirming an aspect of ones' self that may be unrelated to the self-threat is not only effective in making people feel better, but changes brain physiology!!

Self- affirmation Theory and positive affirmations


Positive thoughts_Vental striatum _ brain
A brain, obviously.

The ventral striatum of the brain influences motivation, reward, and more!

The VS plays a role in mood, learning, and addiction.

During reward-based decision making, the ventral striatal signal dynamically changes thereby acting as a motivational engine for the continuation of behavior.

Dopamine receptors play a part!
Dopamine & VS

The ventral striatum relies heavily on dopamine.

Dopamine is a neurotransmitter that acts as a messenger between brain cells.

Dopamine signals rise in the ventral striatum in response to things that are rewarding or worth paying attention to.

They fall when we expect a reward--and don't get it.
More on dopamine & foods that we need to make more of it.


There is MRI evidence suggesting that certain neural pathways are increased when people practice self-affirmation tasks
MRI study
Study participants showed increased activity in key regions of the brain's self-processing (medial prefrontal cortex + posterior cingulate cortex) and valuation (ventral striatum + ventral medial prefrontal cortex) systems
Self-affirmation activates brain reward circuitry (aka dopamine receptors in the ventral striatum.)
VS & affirmations
Positive emotion affects cognitive stability
Affecting dopamine receptors in the frontal lobe
Positive emotion and stability
Self-affirmation can buffer stress responses
Stress and SA
Positive affirmations help to maintain better self esteem
and decrease unhealthy behaviors such as binge drinking
drinking & +affirmations
Positive affirmations improves COVID-19 preventive behavior
Covid & Positive affirmations
Positive affirmations help alleviate self threat.
Affirmations & slef-threat
Positive affirmations lower heart rate
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Positive affirmations are one technique used that fall under the bigger umbrella of a psychological technique termed cognitive restructuring.

Cognitive restructuring is a group of therapeutic techniques that help people notice and change their negative thinking patterns.

Caveat: Positive affirmations are not designed to be cures for anxiety or depression, nor are they a substitute for clinical treatment of those conditions. But that’s not to say that they won’t help.


As the studies above suggest, positive affirmations can help us to respond in a less defensive & resistant way when we’re presented with life’s difficulties.

I won't ever make you sad.

Whether it’s social pressures, work or scholastic pressures,  health information that makes us feel uncomfortable, or feelings of exclusion, a broader self-concept can be an extremely helpful thing to have.

Join us and make sense of science_Ian and Kochs
My self-concept is humming right now

We can’t always be taking walks in the park with our loved ones. So how do we combat negative self-talk?

'It is very important to generate a good attitude, a good heart, as much as possible. From this, happiness in both the short-term and the long-term for both yourself and others will come.'

self-affirmation theory _make sense of science
Do positive affirmations work?


In order to keep this post from turning into a book, we're focusing on positive affirmations
I would be remiss by not mentioning yoga & mediation, also excellent positive psychology options
As are walks outside, breath control, and forgiveness exercises.
Think of positive affirmations like compliments to oneself.
They bring an immediate sense of pleasure and pride in ourselves or our situation.
Affirmations redirect the mind to focus on the positive sides in ourselves & nudge us to think and act positively.
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'The most important thing is to enjoy your life—to be happy—it’s all that matters.'

Affirmations can be simple statements that we say aloud to ourselves every day. 

A friend and I who email frequently have begun each correspondence with a positive affirmation. It’s changed the tone of our communication and makes us both feel more calm, optimistic, & happy.

So does this cardinal! (courtesy Bing)

Or, to make the affirmations feel more concrete, consider picking up a lovely notebook & filling it once a day with one sentence of positivity. It will only take 3 minutes and change your brain chemistry.

The two journals below are available on amazon. Click on the photos for an affiliate link to purchase.

‘We can only be said to be alive in those moments when our hearts are conscious of our treasures.'

Getting rid of thought is not an option. Positive affirmations aren’t a cure for complicated medical conditions.

But we can try to reframe our attitudes & brain chemistry with one positive affirmation each day.

David Hume, 1711 - 1776. Historian and philosopher
THIS is David Hume.

A last note, the science behind positive affirmations and brain chemistry states that we need to do this consistently, minimally 3 x  a week, to keep the positive effects.

My positive self-talk affirmation as I’m writing, ‘the science behind positive affirmations’ is that I am grateful to each and everyone one of you, for taking the time to read my blog! 

I’d love it if you’d share a positive self-talk affirmation with me in the comments below!


Thank you for reading my post

Join us! Subscribe!


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December 20, 2022 5:19 am

An interesting read. I didn’t know that was a relationship between science and positive affirmations but thanks to your post, I have some new knowledge on this.

December 20, 2022 5:55 am

What a timely post. With 14 days of no sun this post is very helpful. For many years, I have carried a little phrase that states “be resolute with the present hour because it is an infinite value. Love the science behind this. Thanks so much for your great work. Keep smiling!. Mike.

December 20, 2022 6:25 am

Thank you for sharing your knowledge with us. Your visual presentation of science based facts is the first that I have seen in any blog. There are so many wonderful things I have learned from your post.
My positive affirmation: I am a fighter, I am strong and courageous.

Ezioma Kalu
Ezioma Kalu
December 20, 2022 7:18 am

Wow. This is a very insightful post. I didn’t know there was a science behind positive affirmations. Thanks for letting me know.

December 20, 2022 7:20 am

I’m going to start my affirmations today. I am grateful for your amazing post. Thank you.

December 20, 2022 7:26 am

If positive affirmations will help me from panicking over everyday tasks, I’m in. My affirmation is that I am happy there is no snow on the ground today. Excellent post, as always.

Fransic verso
December 20, 2022 7:34 am

Amazing, I like to read positive affirmations, and it helps me to develop a positive mindset. It’s nice to know the science of it.

Molly | Transatlantic Notes
December 20, 2022 7:40 am

I definitely came to using affirmations later than I should have (I put it off thinking it wouldn’t work). When I started making the effort to use them the difference was noticeable (why I share posts about them on my site). Thanks for exploring the science behind it all; this was fascinating!

Becki Kidd
Becki Kidd
December 20, 2022 9:05 am

Thanks for this timely post, Sue! I tend to be negative in my thought process & struggle with keeping it positive. I find I’m more negative towards others, pinpointing things I struggle with myself. When I catch myself doing this, I like to turn that negative into a positive & say it aloud a few times.

Mummy Conquering Anxiety
Mummy Conquering Anxiety
December 20, 2022 1:46 pm

Love everything about this post! Positive affirmations definitely work, and the science behind it is great.

Thrift Plan Enjoy
Thrift Plan Enjoy
December 20, 2022 4:54 pm

I love the fact we are able to change our brain structure. It’s such a revelation and we should all be excited about it.

December 20, 2022 5:07 pm

Positive affirmations are so important and I loved reading all the science behind it! Thanks for sharing!

Amy Laundrie
December 20, 2022 7:04 pm

Here are some of my favorite affirmations. Just typing them out makes me happy. I am kind and loving, and I have a great deal to share with others.Every day in every way I’m getting better, better, and better. I am a radiant being, filled with light and love. Everything is coming to me easily and effortlessly. My life is blossoming in total perfection.
Thanks for the great post, Sue. And happy holidays.

Kelly Diane
December 21, 2022 1:49 am

I’ve never thought about the connection between positive affirmations and science before but I found it really interesting to read your thoughts. My positive affirmation is I am worthy

December 21, 2022 4:17 am

this was an interesting read. would urge you to work on making the blog more accessible, though 🙂 a bit tedious to read with a screen reader. do include alt text in images and GIFS you post 🙂

Isa A
Isa A
December 21, 2022 10:15 am

I also believe that self affirmations work. What we think we become. This leads to change in habits and a good lifestyle and physiology. A good check given to be mindful of it atleast three times a day. Nice research and points as always. Xx
Isa A. Blogger

December 21, 2022 10:29 am

What a ‘positively’ fabulous and timely article! Thanks for the research you put into it and the quotes – several of which I copied down.

Unwanted Life
December 21, 2022 12:48 pm

It’s ridiculous just how long the theory of humours lasted so long in the medical field. It really held back medicine and science

Eva Apelqvist
Eva Apelqvist
December 21, 2022 2:37 pm

Another fabulous post. Thank you. I am dealing with close family members with dementia and have noticed that positive affirmations work wonderfully.
“Aren’t we lucky to be able to look out the window and see Lake Superior?”
“Isn’t it lovely to sit here in front of the fireplace on this snowy day?”
And … most importantly … “I am so grateful that we are able to have a nice dinner together every night and that you are in my life.”
Thank you, Sue!!!

Sarah Collins
Sarah Collins
December 22, 2022 1:58 am

Really interesting post, love the science behind this, I use positive affirmations probably came to them a bit late. Thanks for sharing

Carolyn Holton
Carolyn Holton
December 22, 2022 1:31 pm

Love it! Perfect post for this crazy time of year!!!
Today is going to be a good day 🙂

Her Digital Coffee
January 3, 2023 1:30 pm

Thank you for sharing such an informative post. I love using affirmations and have seen such positive results because of it!

Susan Berk Koch author

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