Gratitude can warm a relationship, while claims about hearts and burnout run ahead of the evidence

Key takeaways

• In a pilot study of 70 people with early-stage heart failure, a combined measure of inflammation fell more after eight weeks of gratitude journaling than with usual care, but resting heart rate variability didn’t change.
• In a one-month experiment with couples, thanking a partner helped most when the thanker saw the partner as responsive, and it brought more negative feelings when the partner seemed unresponsive.
• A randomized trial of a 10-day program that included “three good things” eased health workers’ depression symptoms, but it didn’t significantly reduce its main target, emotional exhaustion.
• In a 2011 online study, gratitude lists lowered self-esteem in people who lean heavily on others for support.
• The John Templeton Foundation funded a $5.6 million gratitude initiative starting in 2012, and some studies here trace to it.

In April 2015, the American Psychological Association sent out a news release with a warm headline: “A Grateful Heart is a Healthier Heart”².

It described research from UC San Diego on 186 adults with Stage B heart failure, meaning their hearts were damaged, for example by a heart attack, but they didn’t yet have symptoms like breathlessness². Those who reported more gratitude also reported better mood and sleep, and they had less inflammation².

The team also ran a small experiment. The release said journaling lowered inflammation and raised heart rate variability, a sign of lower heart risk, during the writing period².

The full results, published in 2016, told a more careful story¹. Inflammation did fall more in the journaling group. But resting heart rate variability didn’t change, and the study had important limits¹.

That pattern runs through gratitude research beyond mood. Our earlier gratitude article covers what thankfulness does for well-being: a small, real lift.

This one asks the follow-up questions. Does gratitude help the body? Does it help relationships and burned-out workers? And when does “just be grateful” do harm?

A gratitude journal eased inflammation in heart patients, in one small pilot

The 2016 pilot, led by Laura Redwine with UC San Diego’s Paul Mills among the authors, enrolled 70 adults with Stage B heart failure, average age 66¹². Half were assigned by chance to write down three to five things they were grateful for each day for eight weeks. The rest got their usual care¹.

People who finished the program wrote on about five days a week¹. Their gratitude scores rose more than the comparison group’s.

What the study found¹:

• Inflammation: An index of four blood markers of inflammation dropped more in the journaling group.
• Resting HRV: Heart rate variability, or HRV, the variation in time between heartbeats, didn’t change at rest.
• While writing: After the eight weeks, the journaling group showed higher HRV during a gratitude-writing task in the lab.
• No clear link: Gratitude scores weren’t significantly tied to the HRV or inflammation results.

The authors listed the limits themselves¹. The sample was small, and blood markers were analyzed for only 43 people. One inflammation marker already differed between groups at the start.

The comparison group did nothing new, so expectations could explain some of the gap. Depression and medicine use weren’t controlled¹.

The study was funded by the National Institutes of Health and by a John Templeton Foundation grant called “Expanding the Science and Practice of Gratitude”¹.

Bigger claims about the heart rest mostly on small or observational studies

A 2023 systematic review in Frontiers in Psychology gathered 19 studies with 2,951 people on gratitude and heart health³. Its authors judged that gratitude may help heart-risk markers and the nervous system, and they asked for better-controlled studies. They didn’t pool the results into an overall effect size.

The studies it found point in different directions³:

• A two-week gratitude journal for 119 young women lowered diastolic blood pressure, the bottom number, compared with a control group.
• A study of 76 women found no direct effect on inflammation markers.
• Several studies only tracked people over time or measured gratitude once, so they show links, not cause.

For sleep and long life, the evidence is covered in our earlier gratitude article, and it is also early.

If you have heart disease, gratitude can sit beside your treatment plan. It isn’t a substitute for blood pressure medicine, cardiac rehab or the habits your cardiologist recommends. And if you track HRV on a wearable, our HRV article explains why one reading says little.

In couples, thanks works best when it lands on a responsive partner

Sara Algoe’s “find, remind and bind” theory proposes that feeling grateful helps you spot a good partner, reminds you of a good one you already have, and draws you closer⁷.

In a 2010 study of more than 65 couples in committed relationships, partners reported their feelings each day⁶. On days when a partner felt more grateful, the relationship tended to go better, and the effect carried into the next day. Feeling indebted, the sense that you owe someone, didn’t bring the same benefits⁶.

A later experiment tested what happens when people express thanks on purpose. Algoe and her colleague Zhaoyang assigned couples who lived together, by chance, to one of two at-home tasks for a month; 47 couples were analyzed⁷. In one, a partner expressed gratitude in several conversations. In the other, a partner responded to the other’s personal disclosures.

The results came with a catch⁷:

• People who expressed gratitude reported more positive emotions and felt more resilient day to day.
• Their ratings of the relationship rose only slightly, not enough to rule out chance.
• The gains depended on how responsive they felt their partner was in a lab conversation.
• Those whose partners seemed less responsive reported more negative emotions than similar people in the comparison group.

The couples were mostly very satisfied at the start, and the study was small⁷. Still, the lesson is useful. Thanks tends to work when it’s received, and if your partner shrugs it off, more thanking may leave you feeling worse.

Gratitude exercises can’t repair a relationship that is harmful or controlling, and none of these studies tested them for that.

Health workers felt less depressed after “three good things.” Burnout barely moved

Researchers J. Bryan Sexton and Kathryn Adair built a version of the classic “three good things” exercise for health care workers⁸. Each night for 15 days, an email prompted participants to write down three good things from the day and their own role in each. Entries took about three minutes.

In a 2019 pilot, 228 health workers started, and 81% were women⁸. A year later, the people who answered follow-up surveys reported less emotional exhaustion and depression and more happiness. The share who screened positive for depression fell from 37.2% to 19.1% after one month⁸.

That pilot had no comparison group, and only about half of participants answered each follow-up. People who started out more depressed or less happy were more likely to drop out⁸.

Next, a team led by Sexton at Duke ran a randomized trial¹⁵. In WISER, published in 2022, health workers got 10 daily text messages linking to short exercises: three good things, awe, kindness, relationships and gratitude letters⁹. After one week, the WISER group beat a waiting-list group on depressive symptoms, happiness, work-life integration, emotional thriving and emotional recovery⁹.

But the trial’s main target, emotional exhaustion, didn’t improve enough to rule out chance (p = 0.11, where 0.05 or lower is the usual bar)⁹. Duke’s news release reported that five of the six outcomes improved by one week¹⁵.

The pilot’s authors made the key point themselves: the exercise doesn’t touch the demands people face on the job or at home⁸. If your job is wearing you down, gratitude can be one small support. Our upcoming article on burnout covers the workplace changes that matter more.

When “just be grateful” backfires

Gratitude exercises are usually pleasant and low risk. “Usually” is the key word.

In a 2011 online study by Sergeant and Mongrain, 772 people signed up and 283 finished¹⁰. Each day, they listed five things they were grateful for, listened to uplifting music or wrote about a childhood memory.

For people high in neediness, meaning they rely heavily on others to feel OK, both the gratitude lists and the music left self-esteem lower than the childhood-memory task did¹⁰. Self-critical people did not show that harm, and they got a slightly larger happiness boost from gratitude¹⁰.

Psychologist Sonja Lyubomirsky of UC Riverside has described a gratitude study with depressed college students that was stopped after many said they felt less happy¹¹. Some were uneasy, even ashamed, about needing the kindness on their lists. Others came up nearly empty, and their mood sank further. The report gives no publication details, so treat it as one researcher’s account.

Lyubomirsky has also raised a concern that hasn’t been tested: asking people who already feel like a burden to list how others helped them might deepen that feeling¹¹.

Gratitude can also be misused. Being thankful for a job doesn’t mean accepting unsafe hours. Being thankful for a partner doesn’t mean excusing mistreatment. Our earlier gratitude article lists signs that gratitude talk has turned into pressure.

In illness and grief, gratitude is an option, not an obligation

A 2016 study tested whether gratitude could help with a specific fear: that breast cancer might come back and prove fatal¹².

University of Delaware researchers assigned 67 women with early-stage breast cancer, by chance, to one of two weekly online tasks for six weeks¹²¹³. One group spent 10 minutes each week writing a private thank-you letter to someone who had helped them. The letters were never sent¹³. The other group listed their recent activities.

The letter writers’ fear that a recurrence would be fatal dropped more than the comparison group’s¹². That change was tied to pursuing goals that mattered to them, not to better mood¹². Their overall fear of recurrence, though, didn’t change¹³.

Letting people come to gratitude at their own pace fits natural-health values. Gratitude is free, needs no product and draws on old traditions of prayer, blessing and thanks. Many people turn to it naturally when life narrows.

But no one should be told to feel thankful for a diagnosis or a death. If you’re grieving, gratitude may come later, in waves, or not for a long time. Our upcoming article on grief goes deeper.

The evidence at a glance

Claim	Evidence level	What the research shows
Gratitude journaling lowers inflammation in heart patients	Promising but early	One pilot of 70 people; no active comparison group; a baseline imbalance1
Gratitude improves resting heart rate variability (HRV)	Not enough evidence	Resting HRV didn’t change in the pilot1
Gratitude lowers blood pressure	Not enough evidence	One trial in young women; a 2023 review called for better studies3
More grateful heart patients feel and sleep better	Not enough evidence that gratitude is the cause	A study of 186 patients found a link, not cause2
Expressing thanks strengthens close relationships	Promising but early	A daily diary study and a one-month experiment; benefits depended on partner responsiveness67
Brief “three good things”-style programs ease health workers’ depression symptoms	Promising but early	An uncontrolled pilot and one randomized trial89
Brief gratitude programs reduce burnout’s emotional exhaustion	Not enough evidence	The randomized trial missed its main target9
Gratitude letters ease death-related fear in cancer survivors	Promising but early	One trial of 67 women; overall fear unchanged1213
Gratitude exercises are harmless for everyone	Evidence says no, or unsafe	Self-esteem fell in needy participants; more negative feelings with unresponsive partners710

Gratitude without pressure: a weekly practice and a letter guide

You don’t need a special journal or an app. The studies here used plain journals, weekly online forms, nightly emails and text messages¹⁸⁹¹³. We found no trial showing that a paid gratitude journal or app works better than a notebook. Our wellness-apps article covers what to check before you pay.

This practice is ours, built from the research above and not tested as a set. Pick one day a week and give it about 10 minutes, the length of the weekly letters in the cancer study¹³. Our earlier gratitude article explains why once a week may be enough.

Choose the version that fits your week:

• A steady week: Write two or three specific moments, and the person or thing behind each. Or send one short thank-you.
• A hard week: Write one sentence that holds both sides: “This week was hard, and ___ helped.” Gratitude can sit next to grief, anger or worry.
• A very hard week: Skip it. Write instead what you need, or a few plain lines about what you did. Skipping is part of the practice.

Skip or stop if:

• you feel guilty, ashamed or “broken” after writing;
• listing others’ help makes you feel like a burden;
• someone is using gratitude to excuse mistreatment or unfair work;
• low mood lasts or deepens (see “When to get help” below).

With a partner: Thank them for one specific act, then notice how it lands. If thanks keep meeting a shrug, talk about it rather than thanking harder.

A letter guide, for when you want to go deeper:

1. Decide: send or keep. In the cancer study, letters were never sent and still helped with one fear¹²¹³. Sending is a separate, optional step.
2. Pick a scene, not a summary. Choose one moment when someone showed up for you. Write where you were and what they did.
3. Trace the ripple. What changed for you because of it, then or since?
4. Write to someone who has died, if you wish. You can keep the letter, read it aloud at a meaningful place or share it with family.
5. Leave the shoulds out. Don’t write that you should be more grateful. Write what’s true.

Questions readers ask

The bottom line

Gratitude does some of its best work between people. Thanks offered to a responsive partner, a note to someone who helped, or a nightly look at what went right can lift mood and draw people closer. Claims that gratitude heals the heart or cures burnout run well ahead of the small studies behind them, and some of that research was funded by a foundation promoting the field.

Use gratitude as an invitation, not a test. Practice weekly, adjust it to hard seasons, skip it when it hurts, and get real help when sadness, grief or exhaustion won’t lift¹⁴.

Related reading

• Gratitude helps a little, and saying thanks to someone helps more
• Spiritual well-being shows up in health data, and so does spiritual struggle
• Living with a condition that isn’t going away
• Your HRV is personal and noisy, so read the trend rather than the day
• Wellness apps help a little if you keep using them, and most people don’t

Sources

1. Redwine L, Henry BL, Pung MA, et al. “A pilot randomized study of a gratitude journaling intervention on HRV and inflammatory biomarkers in Stage B heart failure patients.” Psychosomatic Medicine, 2016;78(6):667-676. pmc.ncbi.nlm.nih.gov
2. American Psychological Association. “A Grateful Heart is a Healthier Heart” (on Mills PJ, et al., Spirituality in Clinical Practice, 2015). APA news release, April 9, 2015. apa.org
3. Wang X, Song C. “The impact of gratitude interventions on patients with cardiovascular disease: a systematic review.” Frontiers in Psychology, 2023;14:1243598. frontiersin.org
4. University of California, Davis. “UC Davis professor receives $5.6 million for gratitude research.” UC Davis News, May 21, 2012. ucdavis.edu
5. University of North Carolina Department of Psychology and Neuroscience. “Dr. Sara Algoe receives research award from the Greater Good Science Center.” UNC, July 21, 2012. psychology.unc.edu
6. Algoe SB, Gable SL, Maisel NC. “It’s the Little Things: Everyday Gratitude as a Booster Shot for Romantic Relationships.” Personal Relationships, 2010 (Wiley-Blackwell news release via ScienceDaily, May 24, 2010). sciencedaily.com
7. Algoe SB, Zhaoyang R. “Positive psychology in context: Effects of expressing gratitude in ongoing relationships depend on perceptions of enactor responsiveness.” Journal of Positive Psychology, 2016;11(4):399-415. pmc.ncbi.nlm.nih.gov
8. Sexton JB, Adair KC. “Forty-five good things: a prospective pilot study of the Three Good Things well-being intervention in the USA for healthcare worker emotional exhaustion, depression, work-life balance and happiness.” BMJ Open, 2019;9(3):e022695. pubmed.ncbi.nlm.nih.gov
9. Duke University researchers (senior author Sexton JB). “Effectiveness of a bite-sized web-based intervention to improve healthcare worker wellbeing: a randomized clinical trial of WISER.” Frontiers in Public Health, December 2022 (abstract via DOAJ). doaj.org
10. Jarrett C. “Positive psychology exercises can be harmful for some” (on Sergeant S, Mongrain M, Journal of Positive Psychology, 2011). British Psychological Society Research Digest, November 14, 2011. bps.org.uk
11. CNN Health. “Is there such a thing as too much gratitude? Turns out sometimes less is more.” CNN, November 26, 2023. amp.cnn.com
12. Otto AK, Szczesny EC, Soriano EC, Laurenceau JP, Siegel SD. “Effects of a randomized gratitude intervention on death-related fear of recurrence in breast cancer survivors.” Health Psychology, 2016;35(12):1320-1328. experts.umn.edu
13. Otto AK. “Goal pursuit mediates effects of a gratitude intervention on death-related fear of recurrence in breast cancer survivors.” Master’s thesis, University of Delaware, 2015. udspace.udel.edu
14. National Institute of Mental Health. “Coping With Traumatic Events.” NIH, last reviewed May 2024. nimh.nih.gov
15. Duke Department of Psychiatry and Behavioral Sciences. “Brief Sessions of Guided Reflections Improve Health Care Worker Burnout.” Duke Psychiatry News, December 2022. psychiatry.duke.edu