Wedding guests making a celebratory toast, symbolizing social bonding, joy, and positive brain chemistry

The Science of Celebrations: How Joy Impacts Our Brains, Bodies, and Microbiomes

Key Takeaways

  • Celebrations with rewarding and social experiences can trigger the release of dopamine, serotonin, and oxytocin—neurochemicals linked to enhanced mood, social bonding, and feelings of happiness.
  • Positive emotions during celebrations can influence gut health through the gut-brain axis, potentially improving digestion and reducing stress-related gut disturbances.
  • Mindful choices, like balancing indulgence with fiber, hydration, and sleep, can support mental and physical health during celebrations.

At ZBiotics, we love digging into the science behind life’s most human moments. And few things feel more universally human than celebrating—whether it’s a birthday, a wedding, a personal win, or simply an excuse to gather with people you care about.

Across cultures and generations, celebrations have helped us mark milestones, share joy, and strengthen community. But beyond the traditions, there is, of course, science behind why these moments feel so good—and how they impact our brains, bodies, and even our gut microbiomes.

Woman blowing out candles on a birthday cake, capturing the joy and social connection that trigger dopamine and serotonin release

The brain chemistry of joy

What makes a celebration so satisfying? As with most things, there’s a chemical explanation. When we come together for positive social experiences—sharing a meal, laughing with friends, raising a glass—our brains respond by releasing key neurotransmitters and hormones that reinforce those good feelings.

Dopamine, often called the "reward chemical," surges when we engage in pleasurable activities. It motivates us to seek out enjoyable experiences—like another toast, another dance, or another story told around the table (Martin et al., 2011). This surge of dopamine not only makes us feel happy and satisfied but also reinforces positive behaviors, encouraging us to pursue and achieve future goals.

Social interactions during celebrations can also increase levels of serotonin, a neurotransmitter that contributes to feelings of well-being and happiness. Healthy levels of serotonin are crucial for maintaining a sense of well-being, satisfaction, and mood stability (Hensler, 2010).

And then there’s oxytocin, sometimes nicknamed the “bonding hormone,” which is released during emotionally significant social interactions like hugging a loved one or sharing a meaningful moment (Matsushita & Nishiki, 2025). While not every celebration floods us with oxytocin, those that foster connection and closeness likely do.

These brain chemicals don’t just make us feel good in the moment. Social connection and shared joy are strongly linked to lower stress, better mental health, and even long-term physical health benefits (Wickramaratne et al., 2022).

Friends sharing drinks in an outdoor setting, illustrating the connection between social joy and gut-brain health

Celebrations, the gut-brain axis, and your microbiome

The effects of a good celebration aren’t limited to your brain—they extend to your gut as well. Thanks to the gut-brain axis—the complex communication network connecting your brain and gastrointestinal system—your mood and gut health are closely linked. When exploring the gut-brain axis in the direction of brain to gut, researchers found that your central nervous system plays a big role in healthy digestion and gut function (Browning & Travagli, 2016). Stress is well-known to disrupt digestion and the gut microbiome, which is part of why sharing joyful moments can be so physically restorative (Appleton, 2018).

Of course, celebrations also tend to involve rich foods, alcohol, and disrupted routines. These factors can temporarily alter the composition and activity of the gut microbiome. For example, alcohol consumption is linked to changes in microbial diversity and increased gut permeability (Canesso et al., 2014). Similarly, short-term dietary changes—like indulging in more sugar or fat—can shift the microbiome (David et al., 2013).

The good news? The microbiome is highly adaptable. Most healthy individuals rebound quickly from temporary shifts, especially if they are already supporting their gut microbiome by eating fiber-rich, gut-friendly foods (Zmora et al., 2019; David et al., 2014).

ZBiotics Pre-Alcohol bottles next to champagne glasses on a wedding table, highlighting mindful choices for gut health during festivities

Celebrating responsibly

While celebrating can be good for you, like anything, balance is key. Here are a few tips to help you enjoy the benefits of celebrations while supporting your gut and overall well-being:

  • Indulge in moderation and balance it with gut-friendly choices. Enjoy the desserts and drinks, but don’t forget fiber-rich foods, fermented snacks, and hydration. These can help moderate your intake and support your microbiome during and after the festivities.
  • Prioritize sleep when possible. Late nights happen, but sleep is critical for both mood and gut health. Try to facilitate healthy, high-quality sleep even when celebrating, and/or plan for recovery if you’re staying out late.
  • Counter any guilt or anxiety by embracing celebrations as an opportunity to reduce stress and strengthen connections. When enjoyed responsibly, celebrations support both mental well-being and gut health.

The takeaway: celebration is human and healthy

Ultimately, celebrating is more than just fun—it can be biologically good for us. Science shows that celebration reinforces social bonds, boosts feel-good brain chemistry, and—when balanced—supports both mental and gut health. So whether you’re marking a milestone or just catching up with old friends, know that the research is on your side.

Here’s to many more moments of joy—rooted in connection, celebration, and a little bit of gut biology.