Suddenly last April, my body forgot how to create solid feces. I wasn't constipated—I had the “liquid blues,” a throwback to the relentless diarrhea I had experienced a decade ago, when I first started taking HIV meds.

By day three I was worried. I would risk dehydration if I didn't somehow help my body along. I was about to call my doctor when a friend suggested cold-pressed aloe. My wife, Gwenn, ran to Whole Foods and found a pint bottle of Aloe Life orange papaya flavored aloe concentrate ($14). I drank two teaspoons mixed in a glass of water at 8 p.m. and again around midnight. (Cold pressing is said to produce the purest, most nutrient-rich product.)

The next morning I celebrated Earth Day with an actual bowel movement.

The turnaround was amazing. I have no idea what had thrown my body out of whack, but if it happens again, I'll know what to do. Aloe interacts with some drugs (including some for diabetes), and it can sometimes cause diarrhea. But it saved my (Earth) Day.