Have you ever caught yourself thinking, “I haven’t laughed much lately…”?
Whether it’s work, house chores, or studying, our busy daily lives can easily make our smiles less frequent. But laughter isn’t just about feeling good—it may have a surprisingly strong effect on both mental and physical health.
A recent study from Japan explored the relationship between how often people laugh in daily life and the risk of developing depression over a six-year period (Tamada et al., 2025). Here, we’ll break down the findings and share practical tips on how to incorporate laughter into your everyday life.
1. Why Laughter Matters for Mental Health
We are taught from childhood that “smiles are the best form of communication.” And indeed, anyone can recall moments when laughter lifted their mood. But scientifically, how much does laughter actually help prevent depression? Until recently, this was still unclear.
Past studies have shown that structured laughter interventions—like laughter yoga or comedy sessions—can improve mood over several weeks to a few months (van der Wal & Kok, 2019). However, research examining whether “natural laughter” in everyday life can reduce long-term depression risk has been scarce.
2. What a 6-Year Study Revealed
Researchers from Tohoku University and colleagues (Tamada et al., 2025) conducted a six-year survey from 2016 to 2022, involving about 32,666 Japanese adults aged 65 and older. Participants were asked: “How often do you laugh in daily life?” Their answers were categorized as:
- Almost every day
- 1–5 days per week
- 1–3 days per month
- Almost never
By 2022, researchers tracked who had developed symptoms of depression and found striking results:
| Frequency of Laughter | Depression Incidence |
|---|---|
| Almost every day | 10.6% |
| 1–5 days/week | 15.7% |
| 1–3 days/month | 21.7% |
| Almost never | 30.0% |
After adjusting for various factors, those who laughed “almost never” had a 49% higher risk of developing depression compared to those who laughed almost every day (Tamada et al., 2025). Moreover, a clear dose-response relationship was observed—the less people laughed, the higher their depression risk.
In short, frequent laughter in daily life may protect against depression.
3. The Power of Laughter Goes Beyond Mood
So why might laughter help safeguard mental health? Researchers point to several physiological and psychosocial mechanisms.
Physiological effects:
Laughing reduces stress hormones such as cortisol, stabilizes blood pressure and heart rate, and may even enhance immune function (Kramer & Leitao, 2023; Bennett & Lengacher, 2009). These effects can boost resilience and overall well-being.
Psychological and social effects:
Laughter strengthens social bonds, reduces loneliness, and increases social support—all factors that can lower depression risk (Scott et al., 2014; Santini et al., 2020). Interestingly, the study accounted for social activity levels, suggesting that laughter itself—beyond being socially active—contributes to mental health.
4. Natural Laughter Matters Most
You don’t need to force yourself to watch comedy shows or join laughter yoga classes. The study emphasizes the importance of spontaneous laughter in everyday life—laughing with friends, family, or colleagues can reduce depression risk (Tamada et al., 2022).
The key is not to force it. Simply creating opportunities for natural laughter is what counts.
5. Laughter is Important for All Ages
While the study focused on older adults, the benefits of laughter apply to younger generations too. Adults aged 20–50 often face high stress from work and family responsibilities. Incorporating laughter into daily routines may help relieve stress and reduce depression risk.
Practical examples:
- Sharing funny stories with colleagues during lunch
- Watching amusing short videos online
- Playing board games or chatting humorously with family
Even small moments of laughter throughout the day can make a difference.
6. Limitations and Considerations
Self-reported laughter frequency:
Participants reported how often they laughed, which may differ from actual behavior. Social desirability bias could influence responses.
Observational study:
This was an observational study, so we cannot definitively say that laughter prevents depression. Other factors such as sleep, personality, or lifestyle may play a role. Still, the study adjusted for prior depressive symptoms and social activity, lending credibility to the findings.
Cultural differences:
Laughing habits and their social significance vary across cultures. While this study involved Japanese older adults, the physiological and psychological benefits of laughter are likely broadly applicable.
7. Tips for Bringing More Laughter into Your Life
The 6-year study highlights that daily laughter may contribute to long-term mental health, not just for older adults but for all age groups.
Easy ways to incorporate laughter:
- Share humor during conversations with friends or family
- Watch funny videos or read comics for a few minutes a day
- Engage in hobbies or exercise with social interaction that encourages smiles
- Keep a “smile diary” to record moments when you laughed
Remember, the goal is enjoyment, not obligation. Small, consistent doses of laughter can have a surprisingly big impact on mental well-being.
References
Tamada Y, Saito M, Ohira T, et al. Frequency of laughter and depression onset among older adults: A 6-year longitudinal study from the Japan Gerontological Evaluation Study. J Affect Disord. 2025 Sep 4;392:120209. doi: 10.1016/j.jad.2025.120209. Online ahead of print.
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