Hi,
At the beginning of my keto diet I had really bad cramps in my feet and calves.
Salt did help.
However I noticed after I guess overdoing with salt that it was affecting somehow my kidneys or it is just my assumption of the uncomfortable filling in the back where kidneys are located.
So finally I used salt in around 3 grams per day. I was taking some more like half a teaspoon when I was experiencing cramps and relaxing effect on cramp was after around 10 minutes or even faster.
Bone broth was and is also helpful. Somehow it works for me :).
Drinking to much pure water when not thirsty was creating similar thing in me (tendency to cramps). Better to drink broth.
I also noticed that eating cashew butter or other nuts may cause in me cramps. Do not know how it works but it happend quite a lot of time so there might be a link. Also coconut milk works in that way for me that I may experience cramps in the night after a meal with this food stuff.
After cold shower I also experience tendency in my legs and feet to have cramps. Maybe this indicates also some imbalance in electrolytes? Cramps after cold shower are not that strong as at the beginning of keto diet for me. After few cold showers I took, they just resolved by its own.