Greens On-the-Go Juice

1. To the jar of a blender, add the cucumber along with 1/2 cup of the grapefruit juice. Blend on high speed until smooth. Continuing adding enough spinach, celery, and parsley so that the blender is no more than three-fourths full. Blend on high speed until smooth, stopping the blender intermittently to scrape the sides and press the ingredients into the center if necessary. Continue adding and blending until no veggies remain. (Add some of the remaining grapefruit juice at this stage, only if necessary to help the blending process.)
2. Strain the juice, if desired. Stir in the remaining grapefruit juice.
3. Divide the juice among 4 glasses (no smaller than 12 ounces) or resealable drinking cups. Serve immediately or refrigerate for up to 2 days.

Reprinted with permission from The Biggest Loser: Quick and Easy Cookbook