As "Better Than Before" author Gretchen Rubin knows, happiness and kindness go hand in hand.
The big takeaway? Being kind makes us — and the people around us — happy. But in case you need some extra incentive to do good things for others this busy holiday season, Rubin reminds us why it pays to be kind.
1. It contributes to your self-worth.
You'll feel better about yourself if you do good deeds.
"That's one of the nicest things about human nature, that we tend to feel better about ourselves when we help people," Rubin told TODAY. "That's a good thing!"
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Science is on her side: "Research shows that people who are happier are more altruistic," she said. "They have the emotional wherewithal to help people."
2. It strengthens your relationships.
Rubin, whose book "Better Than Before" comes out on paperback Dec. 15, tells a story she'll never forget about a man she barely knew, who has since become a good friend.
"I went to a dinner party and there was a speaker, so you were supposed to fill your plate and then sit down." But Rubin didn't know anyone at the event.
"I was standing there feeling really uncomfortable, and this guy patted the seat next to him and said, 'Come sit here,'" she continued. "He saw that I was standing there and didn't know what to do. I have never forgotten it."
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Kind acts like those (as opposed to random acts of kindness, like paying a stranger's tab at Starbucks) are valuable because people will remember them, she said, which makes your relationship stronger.
3. It recharges your battery.
"We're like cell phones that need to be plugged into the wall," Rubin said.
And while it sounds counterintuitive, taking time out of a busy schedule to do something good can give you that charge. Rubin says it's a myth that we're "too busy" all the time — that ubiquitous excuse for everything from skipping a friend's birthday party to ignoring a phone call from your mom.
"Sometimes when you're feeling depleted, and you take the time to give, it reassures you that you can give," she explained. "If you feel like you have no time, but then you sit down and have a long conversation with your grandmother, or if you don't have much money and you give $50 to a cause or a charity that's important to you, it reminds you that you do have enough to give."
A tip for making time for nice deeds that are important to you but seem to slip through the cracks? Put it on your calendar. Rubin says we're more likely to do things when they're actually written down and given a time and date.
"I always say to myself, 'I have plenty of times for the things that are important.'"