I spent 10 years studying what makes us happy in life—here's the No. 1 thing I overlooked the entire time

Ten years ago, I set out to find the framework for a happier life. Testing the wisdom of the ages with scientific research, I learned how to strengthen my relationships, increase energy and more.

But a few years ago, I started to notice that I felt stuck in my head — disconnected from other people and from myself.

Suddenly, I realized that I'd been treating my body like a car that my brain was driving around town. But it was actually my body — through my five senses — that was my essential con­nection to the world.

I didn't want to come to the end of my life and think, "So many things happened to me. I wish I'd been paying attention." 

While writing my book, "Life in Five Senses," I discovered some surprising ways that our senses can help us to focus more deeply, live longer and spark happiness.

1. Need a burst of energy and cheer? Use your sense of smell.

When you need a quick lift, you can indulge in beautiful smells by taking a deep whiff of clean towels at home or fine wood at a hardware store.

With a scent, you can't bookmark it, rewind it, stockpile it or save it for later. It ties you the present moment and, at the same time, can transport you to your past.

The smell of eucalyptus, for example, always reminds me of the 10 lovely months I lived in San Francisco.

Smells can boost awareness, too. When I left my building one bright morning, I received several neighborhood updates: It was trash day; the food cart on the corner was frying bacon; and a passerby was enjoying some early marijuana.

2. Stressed out? Use your sense of touch.

Items such as pop toys, fidget spinners and therapy dough can help us to feel calmer. 

A friend told me, "My aunt works in palliative care, and they just recently put in a big order of light, cuddly throws. It's really comforting for people to touch something soft and warm."

I have my own idiosyncratic way to use my sense of touch. When I'm in a situation that makes me anxious, like being backstage before giving a big talk, I hold a pen. 

3. Feeling distracted and unproductive? Use your sense of sound.

I've found that the more I can control my surroundings, the less bothered I am by errant noises.

When I took my laptop to a small neighborhood library to write in its quiet workroom, for example, I got distracted by someone's cough. But when I worked in a bustling coffee shop, the conversations around me helped me concentrate. The whirring blender didn't bother me either.

Just as you do periodic sweeps of your home to clear clutter, you can clear clatter, too.

Ask your partner to use earbuds on video calls if you both work at home. Or, to cut down on spam calls, register your phone number with the National Do Not Call Registry.

4. Need a creative spark? Use your sense of sight.

When I need some inspiration, I try to spot the small details. During my daily walks, instead of getting lost in my thoughts, I give myself assignments: Look for the color purple, or at the trees, or at hats.

I'd study the materials of the different apartment buildings. One was made of dark red-brown bricks, the next of white brick, the next of yellowish smooth stone slabs. I had walked these blocks hundreds of times, and I'd never noticed the mismatch before.

The more I looked, the stronger the habit grew. I found more beauty — in the surprising orange tweed of a woman's coat, in a flock of birds wheeling overhead — and I also found more whimsy.

5. Want to feel closer to other people? Use your sense of taste.

Enjoying unique foods and flavors with other people is one of the most ancient and universal human customs. 

To further connect with people, I threw a "Taste Party." Together, my friends and I rated varieties of apples, chocolate and chips. We tasted ketchup to detect the five basic tastes of sweet, sour, salty, bitter, and umami. We reminisced about the candy we ate as kids.

It was tremendously fun. We weren't just socializing; we were sharing a sensory experience, and it got us all laughing. Our conversations felt unusually warm and intimate. 

My exploration of the five senses has transformed my life. Every day, I tap into their power to connect me to ordinary moments that I want to experience and remember — and I'll never take ketchup for granted again.  

Gretchen Rubin is a happiness researcher and bestselling author of "The Happiness Project." Her most recent book is "Life in Five Senses: How Exploring the Senses Got Me Out of My Head and Into the World." She's also host of the popular podcast, Happier with Gretchen Rubin, and founder of the award-winning Happier app. Follow her on Twitter and Instagram.

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