They're also more likely to live longer. If you're feeling unhappy, you may be overlooking easy ways to be more productive and feel more successful.
To change your outlook on life, begin by considering how you use your time. Adjusting your habits, specifically your morning rituals, could make you feel happier, according to Tom Corley, financial planner and author of "Change Your Habits, Change Your Life."
"Good daily habits enable you to focus every day on pursuing success," Corley writes. "They put success on autopilot."
Here are four morning habits to give up if you want to be more successful:
People are more likely to check their smartphone first thing in the morning than they are to brush their teeth, put on their robe, talk to their partner or have coffee, a 2015 Bank of America report on technology found.
That morning routine is potentially damaging. Reading just one negative email could lead you to report having a bad day hours later, says Michelle Gielan, psychology researcher and bestselling author.
"Even if you have one good and one bad [email], the bad always seem more powerful," Gielan says in a recent episode of "The Productivityist Podcast. "
Skipping breakfast or eating breakfast foods high in sugar, simple carbohydrates or unhealthy fats could be increasing your health risks and making you feel sluggish and less mentally sharp, a growing body of research shows.
Instead, reach for healthier options. Whole grain foods and certain types of nuts and fruits make people feel more energized, doctors say.
"Put simply, what you eat directly affects the structure and function of your brain and, ultimately, your mood," writes Harvard Medical School professor and board-certified doctor Eva Selhub.
If you don't have time to make food in the morning, pack something the night before. Your brain will thank you.
Making just a short amount of time to exercise in the morning could leave you feeling happier and more relaxed throughout the day. Research conducted at Princeton University found that physical activity actually "reorganizes the brain" so that stress and anxiety "is less likely to interfere with normal brain function."
Perhaps that's why even the most successful people make time to get moving. Billionaire Richard Branson wakes up early every morning to play tennis or bike, maintaining that it "doubles" his productivity. Facebook CEO and founder Mark Zuckerberg says he tries to work out in the mornings at least three times a week.
Exercise doesn't have to be high-intensity to boost happiness. Going on a short walk amplifies creativity, Stanford researchers found. And being outside and getting sunlight helps decrease cortisol levels, which rise when you're stressed.
The best thing you can do to have a great morning is to get a good night's sleep the night before. Adults who get eight or more hours of sleep are more likely to report being happy and healthy, according to Gallup research.
"Americans aged 30 to 64 who usually get five hours of sleep have significantly lower well-being than those who usually get six hours of sleep," Gallup researchers write.
If you're having a difficult time falling sleep, experts recommend trading your nighttime routine of scrolling through your phone for reading a physical book or engaging in a relaxing activity such as drawing.
"Most people need a good hour of winding down down time before they're just physically and mentally ready to go bed," says Dr. Philip Gehrman, assistant professor of psychiatry at The University of Pennsylvania's Perelman School of Medicine — even Bill Gates.
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