Ask anyone who's ever succeeded on a diet or similar change-your-life health plan about the benefits, and they typically say the same thing. Some may say that their clothes fit better. Some may say that their sex life got hotter. But you know what almost all of them say when you ask them the biggest change they felt?

More energy.

Stronger, zippier, peppier. Happier. With a "can do" attitude and enough confidence to conquer the world.

Often, people in that scenario have a hard time explaining what "more energy" really means—except for the fact that they feel better getting up and going rather than lying down and snoring. But that key phrase—more energy—lies at the heart of what feeling beautiful is all about. You can be in the best relationship in the world and have celestial-quality facial features, but if you'd rather lie on the couch watching 12 hours of trashy reality shows than moving, living, loving and passionately doing, then your life may feel about as satisfying as a one-bean dinner.

And isn't that what feeling beautiful is about—having passion for life and the energy to act out that passion?

13 ways to restore your energy

• Find more keys to inner and outer beauty in YOU: Being Beautiful by Dr. Oz and Dr. Michael Roizen

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