Did a study show expressing gratitude improves your physical health?

Quickly Dismissed

Authors claim their study showed expressing gratitude improves your health and extends your life. I explain why I am skeptical of their claims.

This Quickly Dismissed post covers inflated claims from an UK group they made about  a simple laboratory experiment.

The claims don’t stand up to scrutiny. Evaluated in the context of other exaggerated claims  in the positive psychology literature from small sized studies with significant design flaws, this study serves as an example of a strong confirmation bias. Probing it can provide tips for what to look for in other studies.

The accomplished senior investigator of the group surely knows the claims are unwarranted.

Ungrateful comments about advice to be grateful

Promoters of positive psychology get particularly annoying in their insistence that we should practice gratitude or risk putting our health and well-being at risk.

They shame us with claims we do not express enough  gratitude. They insist we program expressing gratitude into our daily lives, even while remaining  ignorant of whether the particular circumstances of our life warrant being grateful or provide a suitable  opportunity to express gratitude.

Before we get on to the study, indulge me and let   me vent about being chastised for not expressing enough gratitude. The admonition comes from a positive psychology advice expert who does not know me, but presumes I would like his advice.

Oh, take your advice and shove it. I would be grateful if you did.

seph fontane pennock

Seph Fontane Pennock Cofounder Positive Psychology Program

Seph Fontane Pennock sends out regular email alerts, a recent one –

Hi James,

The #1 thing that holds people back from having a smooooothe-as-honey lifestyle, where you can just get up, feel great, and connect with other people in meaningful ways, is…

(Drum roll)

I am not making this up! How many #1 things can positive psychology advice gives provide before we call a moratorium on #1 things?

Not being grateful.

500 awesomestYou can have all the money and achievements in the world. But, if you are grateful for nothing, it’s like no matter what you make or do, life simply will not get any better. It’s like everything falls into the black hole of things we take for granted.

This is one of the reasons why we end up striving for more in our lives. More friends, more money, more status. Because how can you ever have enough if you don’t appreciate what you have?

Funny how this sounds just it come from the dueling preachers who stand outside Love Park in Philadelphia on weekends, with blaring sound systems and tough-looking disciples. Sinners, repent!

And you know what?

I think that’s a deep shame. Especially because most of us (in the Western world) should be grateful for our lives in a way that’s almost apologetic.

Ah, here’s the inevitable  shaming.

So Seph, what’s the solution?

I’m glad you asked.

I didn’t ask, Seph. This is a dumb rhetorical device. Please don’t be grateful to for me for asking.

The most powerful way I’ve found to overcome the danger of getting used to things is to be actively grateful for them.

Ah, the usual schtick of identifying the dangers of everyday life and having  a powerful  way handy to overcome them.

So I hereby invite you to lift the veil that is clouding the wonders life has in store for you, every day again, by expressing your gratitude.

“Hereby”? I have to instruct Dutch students in my writing workshops not to start their cover letters with “I hereby submit…” I explained to them that no one talks that way anymore except dead people, Shakespearean actors, and maybe a few people in the UK who think they are royalty.

By saying to someone: “Thank you so much for doing [x], it means the world to me”.

By jotting down 3-5 things you’re grateful for before you go to sleep.

By looking your kids deeply into their eyes and knowing that the moment will not last forever and letting that knowledge transform into a mindfulness that allows you to be fully present with them.

I have to jot a note to myself that the next time I fly, I swipe a couple of vomit bags out of the back pockets of the seats in front of me for occasions like this.

Because so many of us positive psychology practitioners KNOW how powerful meditation, gratitude and self-compassion are, but so few of us are actually practicing as we preach.

Well, I dispute that many “positive psychology practitioners KNOW” and could skeptically ask how they KNOW this, but for the sake of getting through this, I’ll let this go.

So let’s change that.

Right here.

Right now.

If you are with me, simply write down 3 things you are grateful for today.

[…take a minute…]

Done?

Great.

Just when I thought Seth was done, he tacked on a a PS

P.s.: if you like, you can send me the 3 things you’re grateful for in reply to this email. Even though I can’t always reply to every email, I love hearing from you!

The Study

Jackowska M, Brown J, Ronaldson A, Steptoe A. The impact of a brief gratitude intervention on subjective well-being, biology and sleep. Journal of health psychology. 2015 Mar 2:1359105315572455.

Abstract here

Full text available here 

  • 119 women were assigned to (1) 2 weeks of either practicing a gratitude intervention, an (2) active control condition in which they simply reported on everyday events, or (3) a no-treatment control condition.
  • The authors examined effects on a range of outcomes, including self-report well-being and mental health, but also measures of cardiovascular and neuroendocrine function
  • They concluded the gratitude intervention elicited increases in hedonic well-being, optimism and sleep quality along with decreases in diastolic blood pressure.

Basis of my skepticism. The authors exposed 40 women who studied or worked at a university to an intervention and evaluated its effects on 12 variables. Knowing only that it was 12 variables and only 40 women in the intervention group,  I would be skeptical about the low power of such a small number of subjects to detect differences, but also the false positive findings arising from so many statistical tests.

But the crucial problem lay is the study having two control groups, but the authors focusing on whether any differences occurred between the gratitude intervention and either of the control groups. So, instead of 12 statistical tests, they have 12 x 2  = 24, taking into account the gratitude vs active control and gratitude vs. no-treatment control.

The table below says it all, if you look closely. The only variable for which the gratitude intervention differed from both control groups was the HADS, the Hospital Anxiety and Depression Scale. It is a composite self-report measure of depression and anxiety symptoms . The authors reported an overall difference, not the usual separate differences for depression or anxiety symptoms. If there were any correction for multiple tests made, this single finding would no longer be statistically significant.

table steptoe gratitude studyMy expectations in approaching this study. There are lots of studies looking at effects on health and well-being of positive psychology interventions like practicing gratitude. This literature dominated by strong claims based on weak or null findings.  But a myth of effectiveness is created by studies selectively report positive findings chosen from an often much wider set of variables. This pattern of reports in the literature establishes an expectation among both authors and editors that positive findings will be forthcoming from studies like these.

My other prior expectation is that when investigators use two control groups, which is good by itself, they often fool themselves by making multiple two group comparisons and focusing on positive results.

eBook_PositivePsychology_345x550I will soon be offering e-books providing skeptical looks at positive psychology and mindfulness, as well as scientific writing courses on the web as I have been doing face-to-face for almost a decade.

Sign up at my new website to get advance notice of the forthcoming e-books and web courses, as well as upcoming blog posts at this and other blog sites.  Get advance notice of forthcoming e-books and web courses. Lots to see at CoyneoftheRealm.com.