[ Because this page is separated into separate sections for meta-analysis/reviews and individual studies, I'm ignoring my typical custom of coloring evidence from then. ]
Lots of research has been done on happiness/well-being, and much of it is centered around correlation rather than causation. If you care about that, you can read about it elsewhere Well-being contributing factors, but I'm focusing only on causal factors here.
See also Muelhauser.
My personal take-aways are
- You should do aerobic exercise 20-30 minutes 3x per week.
- You should meditate at least 10 minutes per day.
- You should make use of a variety of intentional positive psychology interventions, especially mindfulness-based stress reduction and reminiscing.
- You should consider using light therapy.
Exercise RCT Meta-Analyses & Reviews
- Acute exercise has an immediate moderate effect on short-term and long-term memory, while long-term exercise had small and insignificant effects, respectively Roig.
- Aerobic exercise lasting 21-30 minutes reduces anxiety (d=0.41) Petruzzello. Moreover, these effects grow over the first several weeks and anaerobic exercise generally lacked this.
- Both cardio and resistance training improve mood (d=0.69), but should be done only 1-2 times per week for this purpose. Effects shrink over time Arent
- Exercise also improves on 8 of 10 psychological measures examined in Netz, especially self-efficacy (d=0.38) and overall well-being (d=0.30). Strength training had positive effects, but they were generally smaller than cardio's (d=0.16 vs 0.26).
- Aerobic exercise also boosts positive affect (d=0.45) Reed
- Tai Chi reduces stress (d=0.66), anxiety (d=0.66), depression (d=0.56), while improving mood (d=0.45) Tai Chi on psychological well-being: systematic review and meta-analysis. Another meta-analysis found similar results The effects of tai chi on depression, anxiety, and psychological well-being: a systematic review and meta-analysis.
- Exercise reduced anxiety (d=0.48) Wipfli.
- Aerobic exercise improves executive function (D=0.34) Moreau, especially the preadolescent children and older adults Ludyga - both groups with their easily-googleable meta-analyses I won't link to here.
- Exercise improves performance Heyn
Probably the biggest issue with these cardio studies is that, as far as I can tell, all the measures of these various mental health metrics were conducted within 30 minutes of the exercise stopping, so its really unclear whether running actually makes you happier long-term other than that the effect size doesn't appear to shrink over that half hour Petruzzello.
Anaerobic exercise also has significant cognitive benefits, generally of similar magnitude as cardio Northey. However I've yet to see any literature review or meta-analysis claiming that it boosts mood or well-being.
Positive Psychology Intervention (PPI) RCT Meta-Analyses & Reviews
Positive psychology interventions improve mental health along several measures (d~0.3) Sin, Bolier (see also this literature review The added value of the positive: A literature review of positive psychology interventions in organizations).
A 2009 meta-analysis gives some pragmatic advice Sin,:
- Several studies have found that exerting high levels of effort to practice a happiness-boosting strategy, and continuing to practice it even after the intervention is over, results in greater improvements...
- It also appears that a "shotgun" approach, in which individuals practice multiple PPI activities, may be more effective than engaging in only one activity...
Unfortunately, as of 2013, some scholars have claimed that there simply haven't been enough high-quality trials to distinguish which particular PPIs are most effective Bolier so these meta-analyses have generally grouped them all together.
On the other hand, several meta-analyses have been published on the effectiveness of gratitude interventions. One analysis found gratitude interventions improve psychological well-being (d~0.3) even compared to alternative interventions (d~0.2) Davis. This was generally confirmed a year later Dickens. A meta-analysis found even strong effects among youth Renshaw.
Meditation is another PPI. It improves anxiety (d=0.22), depression (d=0.23), pain Goyal and more generally on emotional and relationship measurers, but not much on cognitive measures Sedlmeier. Moreover, when compared to generic relaxation techniques, most of these effects remain, suggesting meditation is doing more than just relaxing people (or at least it relaxes them exceptionally well). Like exercise, the positive effects grow during the first several weeks. Meditation improves sleep quality, but other techniques are comparable Rusch. Unfortunately, I could not find an analysis for how long (in minutes/hours) to meditate for most metrics. The exception is sleep, where they examined 3-42 hours of meditation and found no dose-response. The minimum time studied was 1.25 hours per week. One RCT found that meditation reduces stress even if done immediately after exercise (at least in the short-term) Bahrke See also Luberto. TODO: Zeng. The evidence is more sparse for yoga, but looks more-or-less similar Büssing.
Another PPI is reminiscing, which improves well-being (d~0.5) The effects of reminiscence on psychological well-being in older adults: A meta-analysis.
Next, there are compassion-based PPIs. TODO: Kirby Wilson.
Finally, there's an 8-week course on various PPI techniques called "Mindfulness-based stress reduction" Mindfulness-based stress reduction. In Wikipedia. It has a large effect size (d~0.5) Grossman. I've seen people say one individual study (not a meta-analysis) Felver shows benefits extend at least two weeks, but I've been unable to obtain that study's text.
As with cardio, most of these studies measured changes soon after the intervention, which makes it difficult to determine to what extent these mental health benefits persist long-term.
Other Meta-Analyses & Reviews
- Light therapy reduces depression (d~0.4) even among people with nominally non-seasonal depression. The balance of the evidence especially when using a bright white light in the morning for less than an hour Tao. It's also effective at treating seasonal affective disorder (d~0.4) Pjrek.
- A literature review on insomnia Baglioni ended up concluding that the most consistent evidence exists for melatonin. Meditation, exercise, and hypnotherapy have weaker evidence in favor. There is minimal evidence for herbal pharmacotherapies, light exposure therapy, homeopathy, or dietary supplements. A second review also found exercise to be quite effective on a number of different sleep-related metrics , with the balance of the evidence suggesting exercising ~3 days per week of moderate intensity exercise Vanderlinden.
- Vitamin B improves cognition but not antioxidants or vitamin D Suh.
- Zinc supplementation improves depression da Silva Lai .
- Four reviews found St John's wort improves depression Ramirez Streltzer Venkatanarayanan Röder. A fifth review concluded the evidence was mixed Berner.
Wikipedia contributors. (2020, June 21). Well-being contributing factors. In Wikipedia, The Free Encyclopedia. Retrieved 16:36, June 27, 2020, from https://en.wikipedia.org/w/index.php?title=Well-being_contributing_factors&oldid=963706058
Muelhauser, L. (2011). How to Be Happy. Less Wrong. https://www.lesswrong.com/posts/ZbgCx2ntD5eu8Cno9/how-to-be-happy
Roig, M., Nordbrandt, S., Geertsen, S. S., & Nielsen, J. B. (2013). The effects of cardiovascular exercise on human memory: a review with meta-analysis. Neuroscience & Biobehavioral Reviews, 37(8), 1645-1666. https://doi.org/10.1016/j.neubiorev.2013.06.012
Petruzzello, S. J., Landers, D. M., Hatfield, B. D., Kubitz, K. A., & Salazar, W. (1991). A meta-analysis on the anxiety-reducing effects of acute and chronic exercise. Sports medicine, 11(3), 143-182. https://doi.org/10.2165/00007256-199111030-00002
Arent, S. M., Landers, D. M., & Etnier, J. L. (2000). The effects of exercise on mood in older adults: A meta-analytic review. Journal of Aging and physical Activity, 8(4), 407-430. https://doi.org/10.1123/japa.8.4.407
Netz, Y., Wu, M. J., Becker, B. J., & Tenenbaum, G. (2005). Physical activity and psychological well-being in advanced age: a meta-analysis of intervention studies. Psychology and aging, 20(2), 272.. https://doi.org/10.1037/0882-7922.214.171.1242
Reed, J., & Buck, S. (2009). The effect of regular aerobic exercise on positive-activated affect: A meta-analysis. Psychology of Sport and Exercise, 10(6), 581-594. https://doi.org/10.1016/j.psychsport.2009.05.009
Wang, C., Bannuru, R., Ramel, J., Kupelnick, B., Scott, T., & Schmid, C. H. (2010). Tai Chi on psychological well-being: systematic review and meta-analysis. BMC complementary and alternative medicine, 10(1), 23. https://doi.org/10.1186/1472-6882-10-23
Wang, F., Lee, E. K. O., Wu, T., Benson, H., Fricchione, G., Wang, W., & Yeung, A. S. (2014). The effects of tai chi on depression, anxiety, and psychological well-being: a systematic review and meta-analysis. International journal of behavioral medicine, 21(4), 605-617. https://doi.org/10.1007/s12529-013-9351-9
Goyal, M., Singh, S., Sibinga, E. M., Gould, N. F., Rowland-Seymour, A., Sharma, R., ... & Ranasinghe, P. D. (2014). Meditation programs for psychological stress and well-being: a systematic review and meta-analysis. JAMA internal medicine, 174(3), 357-368. https://doi.org/10.1001/jamainternmed.2013.13018
Sedlmeier, P., Eberth, J., Schwarz, M., Zimmermann, D., Haarig, F., Jaeger, S., & Kunze, S. (2012). The psychological effects of meditation: a meta-analysis. Psychological bulletin, 138(6), 1139. https://psycnet.apa.org/doi/10.1037/a0028168
Sin, N. L., & Lyubomirsky, S. (2009). Enhancing well‐being and alleviating depressive symptoms with positive psychology interventions: A practice‐friendly meta‐analysis. Journal of clinical psychology, 65(5), 467-487. https://doi.org/10.1002%2Fjclp.20593
Bolier, L., Haverman, M., Westerhof, G. J., Riper, H., Smit, F., & Bohlmeijer, E. (2013). Positive psychology interventions: a meta-analysis of randomized controlled studies. BMC public health, 13(1), 119. https://doi.org/10.1186/1471-2458-13-119
Brickman, P., Coates, D., & Janoff-Bulman, R. (1978). Lottery winners and accident victims: Is happiness relative?. Journal of personality and social psychology, 36(8), 917. https://psycnet.apa.org/doi/10.1037/0022-35126.96.36.1997
Gardner, J., & Oswald, A. J. (2007). Money and mental wellbeing: A longitudinal study of medium-sized lottery wins. Journal of health economics, 26(1), 49-60. https://doi.org/10.1016/j.jhealeco.2006.08.004
Rusch, H. L., Rosario, M., Levison, L. M., Olivera, A., Livingston, W. S., Wu, T., & Gill, J. M. (2019). The effect of mindfulness meditation on sleep quality: a systematic review and meta-analysis of randomized controlled trials. Annals of the New York Academy of Sciences, 1445(1), 5. https://dx.doi.org/10.1111%2Fnyas.13996
Wipfli, B. M., Rethorst, C. D., & Landers, D. M. (2008). The anxiolytic effects of exercise: a meta-analysis of randomized trials and dose–response analysis. Journal of Sport and Exercise Psychology, 30(4), 392-410. https://doi.org/10.1123/jsep.30.4.392
Luberto, C. M., Shinday, N., Song, R., Philpotts, L. L., Park, E. R., Fricchione, G. L., & Yeh, G. Y. (2018). A systematic review and meta-analysis of the effects of meditation on empathy, compassion, and prosocial behaviors. Mindfulness, 9(3), 708-724. https://doi.org/10.1007/s12671-017-0841-8
Bahrke, M. S., & Morgan, W. P. (1978). Anxiety reduction following exercise and meditation. Cognitive therapy and research, 2(4), 323-333.
Wikipedia contributors. (2020, July 4). Mindfulness-based stress reduction. In Wikipedia, The Free Encyclopedia. Retrieved 16:42, August 26, 2020, from https://en.wikipedia.org/w/index.php?title=Mindfulness-based_stress_reduction&oldid=965938289
Grossman, P., Niemann, L., Schmidt, S., & Walach, H. (2004). Mindfulness-based stress reduction and health benefits: A meta-analysis. Journal of psychosomatic research, 57(1), 35-43. https://doi.org/10.1016/S0022-3999(03)00573-7
Bohlmeijer, E., Roemer, M., Cuijpers, P., & Smit, F. (2007). The effects of reminiscence on psychological well-being in older adults: A meta-analysis. Aging and Mental Health, 11(3), 291-300. https://doi.org/10.1080/13607860600963547
Felver, J. C., Morton, M. L., & Clawson, A. J. (2018). Mindfulness-based stress reduction reduces psychological distress in college students. College Student Journal, 52(3), 291-298.
Meyers, M. C., van Woerkom, M., & Bakker, A. B. (2013). The added value of the positive: A literature review of positive psychology interventions in organizations. European Journal of Work and Organizational Psychology, 22(5), 618-632. https://doi.org/10.1080/1359432X.2012.694689
Davis, D. E., Choe, E., Meyers, J., Wade, N., Varjas, K., Gifford, A., ... & Worthington Jr, E. L. (2016). Thankful for the little things: A meta-analysis of gratitude interventions. Journal of counseling psychology, 63(1), 20.
Dickens, L. R. (2017). Using gratitude to promote positive change: A series of meta-analyses investigating the effectiveness of gratitude interventions. Basic and Applied Social Psychology, 39(4), 193-208. https://doi.org/10.1080/01973533.2017.1323638
Renshaw, T. L., & Olinger Steeves, R. M. (2016). What good is gratitude in youth and schools? A systematic review and meta‐analysis of correlates and intervention outcomes. Psychology in the Schools, 53(3), 286-305. https://doi.org/10.1002/pits.21903
Kirby, J. N., Tellegen, C. L., & Steindl, S. R. (2017). A meta-analysis of compassion-based interventions: Current state of knowledge and future directions. Behavior Therapy, 48(6), 778-792. https://doi.org/10.1016/j.beth.2017.06.003
Wilson, A. C., Mackintosh, K., Power, K., & Chan, S. W. (2019). Effectiveness of self-compassion related therapies: A systematic review and meta-analysis. Mindfulness, 10(6), 979-995. https://doi.org/10.1007/s12671-018-1037-6
Zeng, X., Chiu, C. P., Wang, R., Oei, T. P., & Leung, F. Y. (2015). The effect of loving-kindness meditation on positive emotions: a meta-analytic review. Frontiers in psychology, 6, 1693.
Tao, L., Jiang, R., Zhang, K., Qian, Z., Chen, P., Lv, Y., & Yao, Y. (2020). Light therapy in Non-seasonal Depression: An update meta-analysis. Psychiatry Research, 113247. https://doi.org/10.1016/j.psychres.2020.113247
Baglioni, C., Bostanova, Z., Bacaro, V., Benz, F., Hertenstein, E., Spiegelhalder, K., ... & Feige, B. (2020). A Systematic Review and Network Meta-Analysis of Randomized Controlled Trials Evaluating the Evidence Base of Melatonin, Light Exposure, Exercise, and Complementary and Alternative Medicine for Patients with Insomnia Disorder. Journal of clinical medicine, 9(6), 1949. https://doi.org/10.3390/jcm9061949
Vanderlinden, J., Boen, F., & van Uffelen, J. G. Z. (2020). Effects of physical activity programs on sleep outcomes in older adults: a systematic review. International Journal of Behavioral Nutrition and Physical Activity, 17(1), 11. https://doi.org/10.1186/s12966-020-0913-3
Suh, S. W., Kim, H. S., Han, J. H., Bae, J. B., Oh, D. J., Han, J. W., & Kim, K. W. (2020). Efficacy of Vitamins on Cognitive Function of Non-Demented People: A Systematic Review and Meta-Analysis. Nutrients, 12(4), 1168. https://doi.org/10.3390/nu12041168
da Silva, L. E. M., de Santana, M. L. P., Costa, P. R. D. F., Pereira, E. M., Nepomuceno, C. M. M., Queiroz, V. A. D. O., ... & de Sena, E. P. (2020). Zinc supplementation combined with antidepressant drugs for treatment of patients with depression: a systematic review and meta-analysis. Nutrition Reviews. https://doi.org/10.1093/nutrit/nuaa039
Lai, J., Moxey, A., Nowak, G., Vashum, K., Bailey, K., & McEvoy, M. (2012). The efficacy of zinc supplementation in depression: systematic review of randomised controlled trials. Journal of affective disorders, 136(1-2), e31-e39. https://doi.org/10.1016/j.jad.2011.06.022
Siwek, M., Dudek, D., Paul, I. A., Sowa-Kućma, M., Zięba, A., Popik, P., ... & Nowak, G. (2009). Zinc supplementation augments efficacy of imipramine in treatment resistant patients: a double blind, placebo-controlled study. Journal of affective disorders, 118(1-3), 187-195. https://doi.org/10.1016/j.jad.2009.02.014
Lomagno, K. A., Hu, F., Riddell, L. J., Booth, A. O., Szymlek-Gay, E. A., Nowson, C. A., & Byrne, L. K. (2014). Increasing iron and zinc in pre-menopausal women and its effects on mood and cognition: a systematic review. Nutrients, 6(11), 5117-5141. https://doi.org/10.3390/nu6115117
Linde, K., Ramirez, G., Mulrow, C. D., Pauls, A., Weidenhammer, W., & Melchart, D. (1996). St John's wort for depression—an overview and meta-analysis of randomised clinical trials. Bmj, 313(7052), 253-258. https://doi.org/10.1136/bmj.313.7052.253
Kim, H. L., Streltzer, J., & Goebert, D. (1999). St. John's wort for depression: a meta-analysis of well-defined clinical trials. The Journal of nervous and mental disease, 187(9), 532-538.
Linde, K., Berner, M., Egger, M., & Mulrow, C. (2005). St John's wort for depression: meta-analysis of randomised controlled trials. The British Journal of Psychiatry, 186(2), 99-107. https://doi.org/10.1192/bjp.186.2.99
Ng, Q. X., Venkatanarayanan, N., & Ho, C. Y. X. (2017). Clinical use of Hypericum perforatum (St John's wort) in depression: a meta-analysis. Journal of affective disorders, 210, 211-221.
Röder, C., Schaefer, M., & Leucht, S. (2004). Meta-analysis of effectiveness and tolerability of treatment of mild to moderate depression with St. John's Wort. Fortschritte der Neurologie-Psychiatrie, 72(6), 330-343. https://doi.org/10.1055/s-2003-812513
Moreau, D., & Chou, E. (2019). The acute effect of high-intensity exercise on executive function: a meta-analysis. Perspectives on Psychological Science, 14(5), 734-764. https://doi.org/10.1177/1745691619850568
Ludyga, S., Gerber, M., Brand, S., Holsboer‐Trachsler, E., & Pühse, U. (2016). Acute effects of moderate aerobic exercise on specific aspects of executive function in different age and fitness groups: A meta‐analysis. Psychophysiology, 53(11), 1611-1626. https://doi.org/10.1111/psyp.12736
Northey, J. M., Cherbuin, N., Pumpa, K. L., Smee, D. J., & Rattray, B. (2018). Exercise interventions for cognitive function in adults older than 50: a systematic review with meta-analysis. British Journal of Sports Medicine, 52(3), 154-160. http://dx.doi.org/10.1136/bjsports-2016-096587
Hendriks, T., de Jong, J., & Cramer, H. (2017). The effects of yoga on positive mental health among healthy adults: a systematic review and meta-analysis. The Journal of Alternative and Complementary Medicine, 23(7), 505-517. https://doi.org/10.1089/acm.2016.0334
Cramer, H., Lauche, R., Langhorst, J., & Dobos, G. (2013). Yoga for depression: A systematic review and meta‐analysis. Depression and anxiety, 30(11), 1068-1083. https://doi.org/10.1002/da.22166
Cabral, P., Meyer, H. B., & Ames, D. (2011). Effectiveness of yoga therapy as a complementary treatment for major psychiatric disorders: a meta-analysis. The primary care companion to CNS disorders, 13(4). https://dx.doi.org/10.4088%2FPCC.10r01068
Büssing, A., Michalsen, A., Khalsa, S. B. S., Telles, S., & Sherman, K. J. (2012). Effects of yoga on mental and physical health: a short summary of reviews. Evidence-Based Complementary and Alternative Medicine, 2012. https://doi.org/10.1155/2012/165410
Lin, K. Y., Hu, Y. T., Chang, K. J., Lin, H. F., & Tsauo, J. Y. (2011). Effects of yoga on psychological health, quality of life, and physical health of patients with cancer: a meta-analysis. Evidence-Based Complementary and Alternative Medicine, 2011. https://doi.org/10.1155/2011/659876
Cramer, H., Lauche, R., Haller, H., Steckhan, N., Michalsen, A., & Dobos, G. (2014). Effects of yoga on cardiovascular disease risk factors: a systematic review and meta-analysis. International journal of cardiology, 173(2), 170-183. https://doi.org/10.1016/j.ijcard.2014.02.017
Pjrek, E., Friedrich, M. E., Cambioli, L., Dold, M., Jäger, F., Komorowski, A., ... & Winkler, D. (2020). The efficacy of light therapy in the treatment of seasonal affective disorder: a meta-analysis of randomized controlled trials. Psychotherapy and psychosomatics, 89(1), 17-24. https://doi.org/10.1159/000502891
Heyn, P., Abreu, B. C., & Ottenbacher, K. J. (2004). The effects of exercise training on elderly persons with cognitive impairment and dementia: a meta-analysis. Archives of physical medicine and rehabilitation, 85(10), 1694-1704. https://doi.org/10.1016/j.apmr.2004.03.019
- A famous study from 1978 found that lottery winners were no happier than their demographics would have predicted Brickman, but a later study found the opposite: that winning the lottery does, in fact, make you happier, even 2 years later Gardner.