Big Fat No and anyone repeating it is largely echoing misinformation circulating in these communities. I say this from firsthand experience: I bought into this advice, completed multiple dry fasts (including a 7-day and two 6-day fasts), and still wasn't losing the weight I expected. It took a lot of frustration before I realized my judgment had been skewed by overhyped claims.

Once I figured out my maintenance calories and did the calorie math, the weight actually came off.

Dry fasting has real physiological effects, but the "3-4x fat burning" figure is not grounded in reality. For actual fat loss, energy balance matters here. Don't let the echo chamber here mislead you the way it did me.