I was on that old grapefruit diet for about six weeks. Ate half a grapefruit before every meal, like the plan said. Felt awful the whole time. The moment it clicked was when I passed out at the gym. My trainer, Mike, asked me what I'd eaten that day. I told him just grapefruit and a small salad. He looked at me and said, 'You're running on fumes, man. That's not food.' Had to sit down with a protein bar. Has anyone else had a diet fail because it just left you with zero energy?
Passing out seems a bit extreme though. Maybe you just needed a snack. These fad diets are silly but they don't usually make people collapse. Sounds like you might have skipped a meal or something on top of it.
That grapefruit diet is no joke. I had a friend who tried it for a month and her hair started falling out in clumps. Your body needs real fuel, not just acid and water. Passing out is a pretty clear sign the plan is broken, not that you skipped a snack. Some of these old fads are dangerously low in protein and calories. What other diets have people tried that just left them wiped out?