2:30 p.m.: I don't want to drink juice anymore.

4 p.m.: Am having trouble finishing the Veggie Vibe this time. There's really not enough variety in this fast. Other than being sick of drinking this stuff, I feel basically fine, though. I'm a giant sack of sloshing liquid, but I'm fine.

5:30 p.m.: I still feel like a walking water balloon. A sharp headache has returned. I really hope this is not the sign of another night like last night.

7 p.m.: So far, so good. Lots of stomach rumbling but the headache's fading. My 2-year-old daughter sees me drinking my cucumber juice and asks if she can have a sip. I let her try it, and she makes a face, pushes the bottle away, and says, "No drink." I agree with her, but if I don't drink this, I get nothing. Then the dog comes by and knocks the bottle to the floor with his tail, spilling it everywhere. Oh well. I'll just have some more water.

9 p.m.: The stomach rumbling gets more intense. I'm really jonesing to eat some solid food, and I'm mentally listing all of the things I might want to eat. Crackers sound really good. Crackers and cheese. Maybe a whole pizza. Caffeine-free herbal tea is allowed after nine, and it's not bad, but not the same as solid food. I decide to walk the dog and go to bed early at 10. When I'm sleeping, I'm not hungry.

Day 3

8 a.m.: Much as I hate to admit, I feel great. And I don't feel the slightest urge to drink coffee. The chlorophyll tastes awful but goes down quick. I am as alert as I ever am this early.

10 a.m.: I get to drink real orange juice, and it is AMAZING. I get a huge burst of energy. There are 200 calories in this one! That is the largest amount of energy I have consumed at one sitting in days. I already know this feeling won't last, and I am not looking forward to my next cucumber-and-spinach concoction, but I'm really enjoying this right now.

11:30 a.m.: I continue to feel semi-wired, though more sharply than I felt earlier. And there's a definite pattern to my daily life now—about 30 minutes after my first puréed-vegetable drink, I need to be in the vicinity of a bathroom. Preferably an empty one, so I can be alone with my thoughts on juice.

1 p.m.: I'm just marking time now. Again, the "master tonic" lemonade is a welcome break from liquid spinach, but I'm not enjoying it. I'm basically numb, just waiting for it all to be over.

3 p.m.: More puréed green vegetables. I'm in the zone now. No feelings of any kind.

5 p.m.: A big office party. Just my luck. There are cookies, bags of candy, a big bowl of banana pudding, flutes of champagne. M&M's never looked so good, though the thought of eating such sweet stuff is a bit sickening at the same time. I would kill to drink something other than cucumber juice, though. I've got to get out of here fast before I snap.

7:30 p.m.: My final juice, the same one I started with: green lemonade. At least there's no cucumber. I plan never to eat a non-pickled cucumber again. The watery blandness is just too reminiscent of vomit to me now. I am so, so hungry—I don't think I can make it if I don't go to sleep really early. In the remaining waking hours of my fast, I spend most of my time planning my first post-fast meal. Unfortunately, I find out that tomorrow morning, I will have to take my daughter to a doctor's appointment that starts very shortly after I have to drop my wife off at her train to work. I won't be able to eat a leisurely pancake breakfast after all.

First things first: Returning to coffee is amazing. Time was short for my first meal, so I picked up the greasiest, most substantial food I could find in the five minutes I had after the train station and before heading to the doctor's: an everything bagel with egg and cheese. I didn't have time to sit down and eat, so I scarfed it down in my car while stopping at red lights. It was disgusting but so satisfying, and the tastes were incredibly intense. Surprisingly, three bites into the bagel I was already full and found myself unable to finish—the juice fast apparently shrunk my stomach. And that's how it went for the next few days: I ate about half of what I would normally and basically didn't have an appetite for heavy food. Otherwise, all the unpleasant side effects have gone away, and I do feel thinner. I didn't get to weigh myself, but I did need to tighten my belt by two holes—so the loss was pretty significant. It wasn't long before my appetite was back to normal, but I still can't look at a cucumber without retching.

Also on Details.com
Rock-Star Yoga
True Blood's Joe Manganiello on How He Got Lean, Mean, and Hungry Like the Werewolf
Matthew Morrison's Body Project
Inside America's Male Body Obsession