Something has changed in your diet or your activities.
The reasons for loss of weight at your age could mean
either you are burning up more calories than you consume
or you are noy absorbing the nutrients because of some
problrm with your intestines. You have to rule out parasites
if you have travelled abroad.You also want to make suore your
is not overactive.You need to get a complete set of
blood tests including celiac panel
Wish you well.