Finland is a nation built by extremes. 

It earned its independence from a country 40 times its size, built cities in a landscape that sees little to no sunlight for months, and is raising generations of children to become “little warriors, not worriers” who respond to hardship head-on…and then—when they grow up—by diving into a half-frozen lake. 🥶

Maybe because of this, Finland has been named the happiest country in the world for the ninth year in a row, according to the 2026 World Happiness Report.

The Finns have a word for this warrior mindset — sisu. Even if they can’t tell you exactly what it means, the idea behind it may help support happiness and well-being.

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Derived from the word for "guts" and "intestines," sisu describes the inner strength that allows people to navigate life's challenges. 💪

It’s often described as part of Finnish identity, tied to resilience, determination, and tenacity—a ‘can-do mindset in the face of adversity,’ as The Seattle Times describes it.

This resilience may be one reason sisu is linked to happiness, and it’s also tied to aging well.

Research suggests that higher psychological resilience is linked to healthier aging and lower mortality risk. 🧓 In fact, it’s considered a precursor to exceptional longevity.

Biologically speaking, ⬇ Lower levels of stress and inflammation and ⬆ better cognition might play a role—and, as a result, resilient people tend to have younger bodies than their birth years suggest.

Resilience also drives purpose, direction, and meaning in life. 

Both resilience and life purpose are associated with healthier stress regulation, including lower stress responses that drive inflammation, oxidative stress, and conditions linked to faster aging and increased disease risk. 

Adaptability matters, too. Resilient people tend to be more open to change and hold a more positive view of aging ☺, which has been linked to healthier habits, lower risk of chronic disease, and longer survival. 

Instead of fighting or internalizing challenges — a changing body, unexpected diagnosis, or lost relationship — you meet them with the resilience and tenacity that you would other hardships. 

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For Finland and other Nordic countries (which take 4 of the 5 top spots for happiest countries), happiness is not “wearing a big smile and laughing,” says author Laura Hall in the BBC. 

It’s more about “subjective well-being,” which means feeling satisfied with life, a positive attitude, and having a sense of purpose.

Finns tend to score high on safety and trust in their government, and sisu comes from knowing this social support exists, says Miika Mäkitalo, CEO of the Finnish company HappyOrNot, in Smithsonian Magazine 🤝.

🗳 With depression at a historic high among US adults (based on 2025 Gallup survey data), it may help to look at a country that defines happiness less by outward cheer and more by everyday flourishing, support, and strength.

Read next: Forget purpose—just be useful

Based on Finnish practice, sisu scholars, and neuroscience, there are a few ways to nurture this inner strength.

📵 Disconnect: Joanna Nylund, author of Sisu: The Finnish Art of Courage, says that sisu can be practiced by making space to disconnect, embrace silence, and spend time alone, building self-awareness that supports resilience.

🧗‍♀ Look back: Build confidence in remembering when you’ve gotten through time times. Sanna Luoma, owner of Sisu Outdoor School for children, tells the Seattle Times. It can sound like: 'Wow, I have a pretty good record in overcoming hard moments in my life.”

👪 Lean on family and community: Think of someone in your life who has overcome hardship. How did they stay resilient? How did it shape you?

🗨 Use a mantra: A simple phrase like “I can handle this,” used repetitively and consistently, can help you stay grounded during stressful times and make healthier choices.

Ask LIV: We’ve added an AI-powered tool that answers your health and longevity questions.

On the Livelong Podcast^TM: Why your workouts stopped working. A conversation with exercise physiologist Dr. Stacy Sims.

Last Tuesday’s issue was about non-sleep deep rest (NSDR). We asked: When you’re exhausted, what do you reach for first?

Top answers:

Personally, I’ve never been good at napping. This struggle inspired me to write about NSDR.

Until next week!