No, and it is the most expensive mistake in the category. The garment already compresses at your true size. Going smaller digs, rolls and creates the line you bought it to remove. Order to your measurements.

For a normal day, fine. For long stretches without a break, doctors advise against it. Cleveland Clinic flags restricted circulation in the legs, reflux and bloating from pressure on the digestive tract, and a raised prolapse risk for women over fifty. Do not sleep in it.

A bodysuit, because there is no edge anywhere across the middle. If you need shorts instead, look for a laser cut or bonded hem rather than a stitched one.

Usually because it is too small, or because the rise is too low for your torso. A piece that sits above the natural waist has something to anchor against. One that stops at the waist has nothing.

Cold water, gentle detergent, and lay it flat to dry. Heat kills elastane, which is the fibre doing all the work. A tumble dryer will cost you the compression within a few washes.

Yes, if the liner is undisturbed and the tags are still on. Try pieces over your own underwear. Once the liner comes off, the piece is yours.