That’s actually an old wives’ tale! You might remember your grandma measuring your neck to see if the pants she’d bought you would fit, but there’s no scientific backing to that method. In fact, you could probably rebuff it with simple logic: a man who wears a size large in jeans will usually have a waist circumference of around 35 and 36 inches, and the average neck circumference is 22 inches. So, no: your waist is not the same size as your neck, and on the extremely odd chance that they both happened to measure somewhat similarly, that would be no more than a coincidence.