In my senior year at Queen's University in Canada — where I studied psychology before earning a master's in public health at Harvard — I decided to conduct a personal experiment: I'd do an act of kindness every day for 108 days, about three and a half months.

I wanted to know: What if I'm not allowed to fall asleep at night until I've connected with at least one friend, family member, or complete stranger in a meaningful way? The question was a precursor to my graduate work, and the next decade of my career, promoting community, belonging, and social health in society. 

I chose 108 because of its auspicious meanings. It's the number of stitches on official Major League baseballs, for example, and the number of suitors who try to marry Penelope in Homer's "Odyssey."

But most importantly to me, 108 is the number of prayer beads on a mala necklace. When I spent a month in a Buddhist monastery in Nepal two years before, I learned to meditate with the mala — holding one bead at a time while reciting a mantra and repeating it 108 times in an effort to reach greater spiritual enlightenment.

In the experiment, acts of kindness would be my daily beads and mantra, reminding me to set out each morning with the intention of connecting. 

'There were opportunities all around me'

Some days, the interactions were simple and lighthearted: Smiling and striking up a conversation with a neighbor; complimenting a clerk at the grocery store; lifting a stroller up stairs for a pregnant mother. 

Other acts were more profound, like staying up late on the phone with a friend until his anxiety subsided, or comforting a collapsed stranger until the ambulance came. 

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I realized how easy it had been to live a whole day without doing anything for anyone else — not because I didn't care but because I was busy, absorbed in my own thoughts, goals, problems, and to-do list. I also realized how easy it was to change this.

There were opportunities all around me to connect; I just had to act on them.

It felt as if my eyesight had been blurry without me knowing. Now I was wearing glasses that brought other people — and my relationship to them — into clear focus.

Prioritizing connection, even as an introvert: 'The effort was always worthwhile'

Over the course of the experiment, I prioritized quality time and deep conversations with friends and family over schoolwork. 

I got to know older women over tea at the nearby retirement residence and homeless men over meals at the nearby shelter. I schemed up ways to make strangers smile, such as leaving toys on the playground and spare coins in laundromats. 

I wrote letters expressing appreciation to people I knew well, like my mom, or didn't know at all, like the janitor in my apartment building. I noticed a woman nervously waiting for an interview and gave her a high five and a pep talk. 

None of these acts of kindness were particularly special or heroic. What mattered was choosing to do them and making a habit of it. 

As an introvert, there were days when I normally would have opted for solitude. There were days when I felt pressure to study for an exam or finish an essay, when serving others seemed like it would be self-destructive. But I found that the effort was always worthwhile and didn't require a lot of time to be meaningful.

Spreading kindness came full circle

Late in February, my dad told me over the phone from Vancouver that he'd been diagnosed with cancer. The next day was the 50th of 108. In celebration, I'd ordered 50 helium balloons and recruited friends to help me hand them out to passersby in downtown Toronto.

Despite being upset and still in shock, I moved forward with the plan. Spending time with friends brought solace, as did being the source of so many smiles and laughs — watching little kids and office workers in suits disappear down the sidewalk with balloons in tow. 

That day, I needed the warmth of connection to offset my grief and anxiety. The point had been bringing joy to others, but doing so brought joy to me.

On the 100th day, a friend and I stood at the entrance to the college library with signs I'd made that said, "Feeling stressed about exams? Have a free hug!" I felt reluctant at first. After all, I was feeling stressed about exams, not to mention nervous about putting myself out there. 

Several hours and hundreds of hugs later, I was on cloud nine. The energy from so many positive interactions vibrated through my body.

'My life was better in every way'

I'd set out to observe how these choices and actions affected who I was as a person — my mood, my long-term goals and values, and my bonds with others. Even without quantitative analysis, the results were unmistakable.

I'd hypothesized that my relationships would broaden and deepen, and they did. I became more in tune with the people around me — listening more intently, empathizing more intensely — and opened up more, inviting others to get closer to me. I felt deeply connected to friends, family, my community, and myself. 

As a result, my day-to-day life seemed elevated, with more meaning, purpose, and fulfillment. 

At the same time, various secondary effects took me by surprise. My motivation to take care of other aspects of my well-being, like exercising and cooking healthy meals, increased. I had more energy and my mental focus sharpened. 

Despite having less time to focus on schoolwork, I was more productive and efficient and actually ended up achieving the highest GPA of all my semesters at college. More interactions led to useful introductions and new ideas, opening doors to unexpected career opportunities. 

I didn't have the language to explain it then, but I know now that what I was doing was strengthening my social muscles and improving my social health.

After 108 days of prioritizing connection, my life was better in just about every way you can imagine.

Kasley Killam, MPH, is a leading expert in social health and author of "The Art and Science of Connection: Why Social Health is the Missing Key to Living Longer, Healthier, and Happier." She's a graduate of the Harvard School of Public Health, sought-after advisor and keynote speaker, and founder of Social Health Labs. She's collaborated with organizations like Google, the U.S. Department of Health and Human Services, and the World Economic Forum.

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Adapted from "The Art and Science of Connection" by Kasley Killam. Reprinted with permission from HarperOne, an imprint of HarperCollins Publishers. Copyright 2024.