Hi Teresa @hopeful33250 @rwinney -- Here's a description of the zero gravity setting.

The position relieves the pressures of gravity from the body by distributing the body's weight evenly to permit for the right amount of needed support. Zero Gravity in the adjustable bed frame allows for the legs and head to be raised at just the right angle to reduce back pressure and increase circulation.

I think the Sleep Number is a good option but I'm looking at a Ghostbed adjustable frame and mattress since I can get two XL single frames together (both adjustable individually) for a lot less money than the Sleep Number. We had a Sleep Number bed when they first came out and I loved it. Over the years it started losing air and we got a Ghostbed mattress and used the Sleep number frame. I was probably too large for the bed ☺ -- 300+ pounder on one side of the bed was me. Fortunately I'm no longer at that weight and eating much healthier.

Here's more information on how the zero gravity helps: https://www.ghostbed.com/education/benefits-of-zero-gravity-adjustable-bed-base/