Underweight

 Let me start by saying be careful what you wish for. I haven't been on here in a couple of years because I met my goal weight just a couple of months after my Rny.  I am 3 1/2 years out now. Starting weight was 250. Goal weight was 130. I am now one of those girls you love to hate if you're overweight. I eat what I want, when I want, as much as I want  (Til I'm full).  I have lost 13 pounds in the past two months. Like I said, it's been 3 1/2 years and I am suddenly dropping weight like crazy no matter what I do. I am 5'6 and 112 pounds. I am so weak. All my blood work comes back normal. I absolutely feel like I am wasting away and dying.  Has anyone else had problems with being unable to stop losing weight????  What did they say was wrong with you? My surgeon was fantastic at first, but his follow up has been crappy at best.  

You may need to find a good gastro.  How much and what are you eating?

Losing when you eat enough ?  That is a problem. Possible issues - malabsorbtion due to ERNY, or parasites, or SIBO, Candida, leaky gut, IBS..etc etc... 

Finding why you not absorbing when you eat enough is important. Maybe you generate too much acid or too much bile? Or not enough? Digestive enzymes can help, probiotics. 

Leaky gut - can cause inflamation, food allergies,  and malabsorbtion - you may need to get tested for food allergies - skin and blood tests. 

If you don't eat enough - it is time to start..

Hyperthyroid or low cortisol - bough may cause wasting...first - hyper metabolism, the second - lack of appetite...

Find a reason - then try to deal with it. 

Have you had other lab work done with your regular doctor? Maybe it's something unrelated to the surgery. Lots of things have weight loss as a symptom...diabetes, infections, cancer...

My first thought was diabetes, but you say all blood work is normal.  My second guess is cancer.  But I have had periods of weight loss when I simply did not want to eat and sometimes have to force myself to up my calorie consumption.

Please track all of your food intake and see if you are just undereating for your body.  If you are eating sufficient calories and still losing weight, then ask your doctor for help in getting the problem diagnosed.  Cancer can be put into remission, but the earlier it is detected and treated, the better your chances of success.

There are many other conditions that can be the cause of your weight loss.  If your doctor is not helping you, then find another doctor.

The vast majority of people eat much more than they think they are. But a small number eat much less than yhey actually are. You could be one of the latter.

Your medical team could use hard numbers to help them diagnose you. Start weighing and logging everything you eat. Every bite. Count every calorie. This information is easy to come by, and could be vital. It's the only place you can start without doctors, scans, and tests.

What Grim said. What are you eating? Are you compliant with vitamins? 

 Guess I should've clarified more. I take vitamins, I have been vegetarian for over a year, I eat lots of nuts and beans and eggs for protein. I use the Lose It! app not to lose weight, but to see how many calories I am getting in. Most days it is close to 2000.  I do pretty much everything wrong. I drink with meals, I have a glass of wine almost every night, I eat cookies and candy. I do not eat bread and rarely have pasta or rice due to an autoimmune disease that makes my mouth too dry to be able to swallow these things.   Cancer did cross my mind, but my blood work in July didn't show any indicators of anything wrong, other than my calcium was a little bit low. So now I take calcium. I have my thyroid checked every three months and it is perfect.  I just wondered why I maintained 130 for several months, and then all the sudden didn't change anything, but started dropping about a pound a week or a little more for no apparent reason. 

If your calcium showed low from blood work, then I'd HIGHLY recommend that you get a DEXA scan to check out your bone density.  Blood will steal calcium (and other minerals) from bones in order to maintain homeostasis in your system, so by the time your blood calcium is low, there is a good chance that your bones are being pillaged.  

I see the  endocrinologist again in November to recheck levels. I am now taking calcium twice a day   

"Checking your levels" and taking calcium now will not give you information about the health of your bones.