My hands & feet are always puffy in the a.m. it goes away with lots of movement. kidneys fine, bp fine, thyroid ok (on synthroid). what could cause?

CHF?: Puffy hands and feet in the morning could be congestive heart failure. It could also certainly be a kidney problem so i would double-check that and make sure they're fine. *agree, but if you've had a complete work-up, see if it improves after days that you avoid salt and alcohol.*.

Salt sensitive?: Hormones, medications, other conditions even genetica can make you more salt sensitive. Try cutting down on salt added to foods and/or increase water intake.. If female, and around menses- totally normal ....

Need adrenal support: Need adaptogen these are specific herbs and minerals to adapt the body for ongoing stress and usually adrenals gets depleted by lack of adaptogen - we use adhs (vasopressin) by biotic in our practice but there are others like noni, amla/chyapro are few others.