My wife had problems with leg and foot cramps during the night, and seems to have reduced their frequency and severity with magnesium supplements. Her problem was definitely diet-related...she logs several miles a day wearing some of the best shoes she can buy (she's a nurse). She's done this for many years, and the only variable in her routine has been diet. Try the magnesium...potassium is not recommended for preventing muscle cramping problems anymore, although it was until about 10 years ago. Neither of these electrolytes should interfere with weight loss.