Alua Arthur has spent more than 10 years working as a "death doula," helping people plan for and transition through their last moments on Earth.

The job taught her a key lesson for feeling happier and more fulfilled: Live like you're dying, which means prioritizing life's small pleasures that most people take for granted, Arthur told author Simon Sinek's "A Bit of Optimism" podcast in an episode that published last week.

Those small pleasures typically include things like health — your literal ability to move through the world each day — and your relationships with the people around you, she said. For Arthur, that meant eating more "delicious food" instead of worrying about her weight, downsizing her expensive apartment, accepting help from other people and making time to exercise, she added.

"I also think I speak a little bit more clearly about how I feel. I brush up against my vulnerability a lot more," said Arthur, a bestselling author and the founder of Going With Grace,  a Los Angeles-based end-of-life planning and support organization.

Arthur found her way into end-of-life work after leaving a law career at the Legal Aid Foundation of Los Angeles, she said — citing her struggles with burnout and clinical depression.

"I took a leave of absence, where I went to Cuba and met a young fellow traveler on a bus," said Arthur. That person was traveling the world after being diagnosed with uterine cancer, and speaking with her helped Arthur "see that I did not like the life that I was living," she said.

After her trip, Arthur's brother-in-law was also diagnosed with cancer. She supported him and her sister through the last two months of his life, and turned her grief into a drive to research death and end-of-life care, she said.

"On my deathbed, I want to arrive having lived fully in this body," she said during a speech at the End Well 2019 symposium. "No longer just a pinprick of life but fully in this body, having used up every single little last bit of skill, gift and talent that I've been given, using it in service of others."

Get ahead of common end-of-life regrets

More than half (58%) of U.S. adults are considered lonely, according to a 2021 report from insurance and health care company The Cigna Group. And at the end of their lives, people tend to wish they prioritized their health, relationships and happiness more, ex-hospice care worker Bronnie Ware wrote in her 2011 book, "The Top Five Regrets of the Dying."

Ware heard these five regrets the most from her patients, she wrote:

1. I wish I'd had the courage to live a life true to myself, not the life others expected of me.
2. I wish I hadn't worked so hard.
3. I wish I'd had the courage to express my feelings.
4. I wish I had stayed in touch with my friends.
5. I wish that I had let myself be happier.

To get ahead of your end-of-life regrets, remind yourself that your time is limited and unpredictable, internal medicine doctor Shoshana Ungerleider told CNBC Make It last year. Routinely ask yourself questions like: How do I want to spend my time? What matters most to me in my life?

"As a doctor, I'd recommend eating a balanced diet, and exercising regularly, and avoiding things like smoking and high-risk activities. Reflecting on mortality should really be on that list," said Ungerleider. "Reflecting on our own mortality throughout life, whether you're 20, 50, 80, whatever, allows us to live better every day with more meaning and purpose in our lives."

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