My RLS increased in hot weather when I would drink 3 or 4 cans of Coke Zero when the RLS got really worse.. Also used 3 Canderel sweeteners in each beverage such as tea or coffee. Saw a program on Channel 5 with a snippet about "aspertamine" and checked things out. I had a lot of other symptoms with RLS that was totally baffling my GP. I stpped taking any form of aspertamine and lo and behold my RLS has decreased to a real minimum level and still waning and also the other symptoms such as tinitus and morning tremors have gone completely. Not saying this is a cure but check how much aspertamine you are taking, it's everywhere as an artificial sweetener, and cut it out to see if it makes a difference.