hi Mel,

Everything you ever wanted to know about Potassium

and ...

The Lowdown on Calcium, Magnesium and Potassium

In general, when consuming a diet with lots of vegetables, fruits and fish, a person can obtain sufficient potassium from food. However, in the early ketogenic stages of low-carbing (Atkins Induction, OWL, Protein Power phase 1) the diet may be lacking for a period of time. As well, being in ketosis causes significant water losses, and with the water, potassium (and magnesium) is lost in the urine .. more than can be replaced by diet alone. Supplements are a simple and sure way to ensure you don't become depleted. Supplemental potassium is safe unless you have pre-existing kidney disease, or are taking certain blood pressure medications which cause the body to retain potassium.

hope this is helpful

Doreen