I read about MJF's mysterious loss of symptoms when he visited a high altitude place, Bhutan in the Himalayas. All sorts of explanations have been given, but here is an interesting one.
In
http://www.celiac.com/blogs/128/Is-t...c-Disease.html
it is suggested that the reason is the gluten free diet in that part of the world. I have seen other pointers to we PWP being intolerant to gluten, and it would explain our mysterious ups and downs.
Ron

At this point, Michael's symptoms are very noticeable and greatly affect the day-to-day activities of his life. Toward the end of the segment, he related that many of his symptoms "mysteriously disappeared" on a recent trip to the Himalayan kingdom of Bhutan. Dr. Mahmet Oz, Oprah's frequent medical spokesman, was also a guest on the show, and was tossing out ideas of why this might be, everything from "they eat a lot of chili's" to the benefits of high altitude, or on medications that Michael took to help with adapting to the altitude. But, I grew very excited by the prospect that Michael J. Fox's improvement was a response to, however accidental, a gluten-free diet! Because, I knew from personal experience that the diet in this part of Asia is largely based on daily consumption of dhalbhat, or rice and dahl (small yellow lentils). Fresh vegetables are rare at high altitudes, but the diet is supplemented by occasional meat, except in some strict Bhuddist or Hindu areas. In 1980 I lived in a neighboring small kingdom of Nepal, and ate almost exclusively a diet of rice, dhal, some vegetables, and occasional sheep or goat meat. Dates, peanut butter, and raisins rounded out our diet, washed down with copious amounts of chai tea, made with black tea and canned evaporated milk. Granted that I also was exercising vigorously much of the time, but looking back, this was when I was at the healthiest, strongest, and most vital in my entire life. Unbeknownst to me, my travels had excluded gluten from my diet for nearly six months. Upon my return to the U.S., and binging on all my favorite gluten-laden foods, I suffered severe intestinal distress, lasting nearly two years. Of course, at the time, both my doctors and I attributed all of my gastrointestinal symptoms to parasites, bacterial infections, and other health problems common to returning travelers. It was decades later that I was diagnosed with a gluten problem, and finally began to recover my health. So, back to the possibility of excluding gluten from the diet having a beneficial effect on Parkinson's, or a possible link between Parkinson's and celiac disease or gluten intolerance,