Yes, very definitely weight loss can be a part of PD. One of our problems is constipation..... This can precede actual diagnosis 15-20-30 years. If a person is constipated, they are not getting nourishment from their food intake and this may be a contributing cause of fatigue.
One of our leading neurologist that used to work different Veterans Hospitals suggests a tasty natural equal mix of: 1/3 Prune Juice - 1/3 Brand (any type works) - 1/3 Applesauce Taking 3 spoonsful each morning keeps me regular plus the old standby: Drink lots of water.
I hope this helps.

sorry Powder !!

i make plastic containers of protein with lots of fruit sometims toss in a Smoothie podwer ,then make it with veggies but still not helping much but his vitals the dr says are perfection ...How does that help weight loss!!! but i do it anyway

My hubby takes a protein drink that I make myself about 3 times a week as he went from 180-now 120 and he has all the healthy foods he needs and wants and also junk food but looking terrible to my eyes anyway and family but I was told that's what Parkinsons does he went from 38 jeans to 32 now

David thank you so much. The magic elixir work, almost too well. Now let's hope his bowels settle into regularity. But it is a terrific fix.