• 456 poor people in Boston from 1939 to 2014 (the Grant Study)
• 268 graduates from Harvard’s classes of 1939–1944 (the Glueck study)

After following these groups and testing them (e.g., blood samples, brain scans) for several decades, the findings have been compiled.

Here’s the conclusion:

“The clearest message that we get from this 75-year study is this: Good relationships keep us happier and healthier. Period.” — Robert Waldinger, director of the Harvard Study of Adult Development

As Melanie Curtin reported on Inc., “The biggest predictor of your happiness and fulfillment overall in life is, basically, love.”

Although the Harvard study lays the foundation, there is other compelling research on the importance of human relationships.

This meta analysis showed a 50% increased likelihood of survival for participants with stronger social relationships. Put simply, if you have healthy relationships, your chances of survival increase by 50%.

Nearly everything in life is impacted by WHO is around you, and how those people support you.

Childhood trauma, for example, is not about what happens to you. But about what happens “inside” of you, according to Dr. Gabor Maté. In other words, if you go through a terribly horrible experience and you have someone there to help you process it, you’ll likely recover quickly. If you don’t have someone to help you through it, you’ll internalize it, isolate yourself, and that trauma will turn into a lifetime of pain.

Healthy relationships, then, could help you avoid addiction. Could help you overcome life’s challenges. Could help you reach higher than you could on your own.

In an article in SCIENCE, authors House, Landis, and Umberson stated the following:

“Social relationships, or the relative lack thereof, constitute a major risk factor for health — rivaling the effect of well established health risk factors such as cigarette smoking, blood pressure, blood lipids, obesity and physical activity”

Transformational relationships

“You can give without loving, but you can’t love without giving.” — John Wooden

The most loving and deep relationships are built on a very simple foundation: giving and gratitude.

When the focus is on what you can give, rather than what you can get, the relationship becomes a gift to both of you.

There’s no holding back.

No keeping score.

Only in such relationships can you be fully present to the moment and fully un-inhibited in the expression of your love.

Giving freely without an expectation of return is essential. As are expressions of gratitude. In fact, this study found that expressions of gratitude have a powerful effect on the other person.

Specifically, this study found regular expressions of gratitude can:

• Increase a person’s self-worth
• Increase a person’s self-efficacy (confidence)
• Increase a person’s prosocial behavior (in other words, when you’re grateful to someone, they become a better person to society at large).
• Increase ability to cope with life’s challenges

Interestingly, Brad Pitt once provided the most beautiful evidence of the science of gratitude and giving. Although he may have forgot …

Whatever happened since, check out this love letter Brad wrote to Angie several years ago:

“My wife got sick. She was constantly nervous because of problems at work, personal life, her failures and problems with children.

She had lost 30 pounds and weighed about 90 pounds in her 35 years. She got very skinny, and was constantly crying. She was not a happy woman. She had suffered from continuing headaches, heart pain and jammed nerves in her back and ribs.

She did not sleep well, falling asleep only in the morning and got tired very quickly during the day. Our relationship was on the verge of break up.

Her beauty was leaving her somewhere, she had bags under her eyes, she was poking her head, and stopped taking care of herself. She refused to shoot the films and rejected any role.

I lost hope and thought that we’ll get divorced soon … But then I decided to act on it. After all I’ve got the most beautiful woman on the earth …

I began to pamper her with flowers, kisses and compliments. I surprised her and pleased her every minute. I gave her lots of gifts and lived just for her. I spoke in public only about her. I incorporated all themes in her direction. I praised her in front of her own and our mutual friends.

You won’t believe it, but she blossomed. She became even better than before. She gained weight, was no longer nervous and she loved me even more than ever.

I had no clue that she CAN love that much. And then I realized one thing: The woman is the reflection of her man. If you love her to the point of madness, she will become it.”

This stuff works. However, relationships aren’t a quick-fix thing. You’ve got to stick to these incredible practices of giving and gratitude or the relationships will stop being transformational. It will die.

Living for something beyond yourself

“For success, like happiness, cannot be pursued; it must ensue, and it only does so as the unintended side-effect of one’s personal dedication to a cause greater than oneself or as the by-product of one’s surrender to a person other than oneself.”— Viktor Frankl

Great power is not what creates great responsibility. Instead, great responsibility is what creates power.

When my wife and I became foster parents of three kids a few years, our lives changed. We had something bigger depending on us. We had to rise to the occasion.

According to what psychologists call, “The pygmalion effect,” you as a person either rise or fall to the demands of your situation. If your situation doesn’t demand much, you won’t rise up.

Having other people depend on you is a beautiful thing. It’s the pressure that will turn you into a diamond. It will cause you to dig deep within yourself, and overcome the addictions and bad habits holding you back.

You have so much more to live for now.

In the digital world we now live in, it’s not about the amount of hours you work. But the amount of thought and humanity you put into your work.

The deeper and more transformative your daily experiences, the more perspective you’ll have into what the world needs. The better you’ll be at your job. The happier you’ll be as a person — despite experiencing hardships throughout life.

When you have people around you who love and help you, you become a different and better person. You become transformed. You become capable of doing amazing things. You are enabled to overcome hardships that would destroy most people.

Do you have deep and loving relationships?

Have you expressed gratitude lately?

Have you given your greatest gifts in complete love and generosity?

This article originally appeared on Medium.