Hi @farahgeo1 The GM diet is a fairly aggressive weight loss plan and from you’ve said this calf muscle cramping came on right after starting this diet. Coincidence? Not sure. Even though you’re drinking mineral water, 3 liters is a significant amount of fluid in a day and can quickly flush elements from your system.
There could be a depletion of some of your key elements such as magnesium, potassium or sodium. A lack of these can cause not only muscle cramping but other health risks such as heart rhythm issues. It might be a good idea to speak with a physician before proceeding with this diet and possibly have a blood test taken to check for imbalances.
Is this area of pain hot, is there swelling in your leg?