Hi, Your hands can get cold and numb for various reasons. I wonder when you say "hands" do you really mean fingers, especially the index fingers or thumbs? And I wonder if they go white as well?
The first thing to look at is medication - you may be getting too much or too many meds, and this might be affecting circulation. Low blood pressure can do this.
The body is an amazing thing - when you walk it starts to supply more blood to the leg muscles and this can mean other parts of the body get less - often the hands and fingers are the parts that suffer. This is sometimes more evident after a meal, when more blood is being directed to the stomach and digestion. So walking, after a meal, especially in cooler or colder weather, could bring it on.
Apart from low blood pressure, this might apply if you had less than perfect peripheral blood circulation. Often, with light exercise, young and fit people have cold hands, adults (40-60yo) often have hot hands, and elderly folk are back to cold hands. This is because the young cope so easily with exercise their circulation hardly changes; the adults on the other hand have to work much harder, and their blood get hot. With elderly folk the body takes a lot longer to get good supplies of blood to the limbs, and even then the hands can feet can stay cold.
So, it's common, and generally means low blood supply. But look at meds first and maybe fitness next.
Beefsteak