Daylight Saving Time: Switch Your Clocks Forward All US states except Arizona and Hawaii observe daylight saving time.

March 9, 2013 -- It's time to spring forward this weekend. Don't forget to set your clock ahead one hour before going to bed Saturday as daylight saving time will begin 2 a.m. Sunday.

The switch will cost you an hour of sleep but you'll gain an extra hour of daylight in the evenings.

Since 2007, daylight saving time in the U.S. has run from the second Sunday of March to the first Sunday of November.

All U.S. states except Hawaii and most of Arizona observe daylight saving time.

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The U.S. territories of American Samoa, Guam, Puerto Rico, Northern Marianas and the Virgin Islands do not move their clocks forward.

Daylight saving time was conceived as a way to save energy.

However, the switch can take its toll on your body and you may be tempted to drink an extra cup or two of coffee.

Nutritionist Ashley Koff told ABC News Radio that you're better off with a good breakfast.

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"Energy comes from food. It comes from nutrient balance of carbohydrate, protein and healthy fats," she said. "Carbohydrates like our waffle and some healthy fat and protein from our peanut butter."

Dr. Raghu Upender, medical director of the Vanderbilt Sleep Disorders Center, told ABC News that it's best to try to stick to your normal weekday sleep schedule during the "spring forward" weekend.

"People tend to delay their sleep during the weekend and tend to go into Monday with less sleep. This can be exaggerated on the Monday following the change to daylight saving time," Upender said.

ABC News' Daniel Bean contributed to this report.