Unexplainable Weight Gain and GI Symptoms with Hashimoto's

After 10 years of struggling to find answers for my GI symptoms and sudden consistent weight gain (100+ lbs), my Dr and I have run out of ideas to explore…

Personal Info:
22 year old female. Currently taking 125 Mcg levothyroxine (Hashimoto's) , 100 mg Zoloft (Anxiety)

Medical Background:
Around 6th grade severe GI issues began to emerge leading to cramping and severe diarrhea after meals, sometimes not even allowing me to finish eating. I absolutely cannot "hold it". At age 17 I had a colonoscopy and biopsies taken which revealed no obvious causes for the GI symptoms. During college (sophomore-senior year) I gained over 100 lbs even while maintaining an active lifestyle walking/biking and working a manual labor type farm job and occasionally going to the gym. This weight gain was initially blamed on starting antidepressant medication (Prozac) but did not subside when medication was switched and/or no longer used. 2 nutritionists stated my diet was not to blame for the weight gain either. In addition, GI symptoms are now even more prominent and include frequent heartburn. I have gone through several elimination diets to narrow down possible food causes of these symptoms, none so far have brought much (if any) relief. So far I have avoided gluten, dairy, cane sugar, processed sugars with no success. I have been tested several times for Cushing's (negative results) and my thyroid panel is within my normal range.

I have had GI issues since a child. Been to dozens of doctors. I have been told everything you can think of. For the last 5months I have had constance diarrhea. NO infection and no nothing again. Ok, so I was told by a RN to ask for some yeast meds. Guess what, that stop it. So, simple. If she knew if. Why then don't GI doctors just don't try something that simple. Crazy thing, I ever heard. But worked, totally stopped. After only 2 pills. Go figure!!

@fishe276
Welcome to Mayo Connect!
I’m sorry to hear what you have been through since age 10.
It sounds as if you have had thorough testing done.
I was going to suggest Cushing’s but then I read your last sentence.
Hashimoto’s often exist with other autoimmune illnesses- celiac disease being a common one. Were you actually tested for celiac disease or just avoiding gluten? If not, then you should be tested.
Weight gain without reason is common with autoimmune diseases. I have experienced the same. Suddenly gaining 1-2 lbs a week while watching my diet.
Such a large weight gain that you have experienced makes me think of Cushing’s. The same happened to my daughter at same age- she eventually was diagnosed with Cushing’s. I don’t know how you were tested but often it is recommended to test at certain intervals since the the cortisol levels can come and go. As far as I know, the best testing is a 24 hr urine for free cortisol.
Your GI symptoms may just be part of your basic illness since they didn’t find anything on colonoscopy.
Are you being followed by Endocrinology and Gastroenterology?
Have they tested all possible hormones?
Is PCOS still a problem?

.....hi, what yeast meds were they? Over the counter? J.

Prescription Diflucan

Have you been checked for sibo?That can cause weight gain.Your GI Doctor can give you a breath test to see if you have it.

I have Hashimoto’s and had lobectomy due to suspicious nodule. I was only put on levothyroxine 88 mcg after surgery (officially diagnosed hypothyroid at that point) despite thyroid antibodies showing up in my blood since 2017. I gained ~80 pounds in 11 years despite not changing diet significantly but I was more sedentary due to extreme fatigue and chronic pain. Thyroid panel levels can be in “normal” range but may not be optimal for you. I recently had my doctor increase my levothyroxine to 100 mcg due to my TSH being 1.42. Historically, I have felt better when my TSH level is at or below 1.0 (normal max. range is 5.0….I am not able to function if it ever got that high). It has been a couple weeks now and I can feel a little improvement in my energy level when I walk (calves feel stronger/less weak). I have had stomach issues since I was 8 to 10 myself (now 54) and have an endoscopy and abdominal ultrasound scheduled this month due to pain that comes and goes near my stomach and liver (have taken ibuprofen for many years due to chronic pain/spinal stenosis). I tested negative in the past for celiac disease and have been tested for other autoimmune issues and theses tests have come back negative. Good luck getting some answers!

I am so very sorry to hear that you’ve been suffering for so long. I am not a Dr., but I had 18” of my sigmoid colon respected in April of 2022 and was diagnosed with Hypothyroidism/Hashimoto’s in November of 2022. I don’t know if there is a correlation. I am taking 112 mcg of Synthroid and 5 mcg of Cytomel (which treats the Hashimoto’s). Since starting the Cytomel, my weight has dropped almost 10 lbs and I am beginning to feel better. Also, due to the Hashimoto’s, I have chosen to given up eating Gluten, Dairy and Soy. The swelling in my body has decreased. I also just had a blood test done to determine what foods I have allergies to and have found that I also have several food allergies. I saw a “Function Medicine Doctor” for the blood test. These Doctor’s do not accept regular insurance, so unfortunately, you have to pay out of pocket. I think it’s worth it! I am staying away from those foods I have allergies to for 6 months to see if I feel a difference, as I have been experiencing balance issues. I am feeling better already. I hope you take this information that I’ve provided and it will help you. Good luck on your personal journey.

I feel you need more gastro testing. I have inflammatory bowel disease and irritable bowel syndrome (IBS .. sounds like you have this with the after you eat issue). It took many years to discover that the main issue I have is spondyloarthritis..an autoinflammatory condition. There is a genetic blood test that any Dr can order for HLA-B27. It is just a normal blood draw. For more info on spondyloarthritis go to http://www.spondylitis.org.

I am 69 and have celiac (HLA-DQ8), collagenous colitis (IBD), hypothyroid, MGUS, and had reactive arthritis (HLA-B27) 33 years ago. The range for "normal" TSH (thyroid stimulating hormone) is between about 0.4 and 5. I just increased to 88 mcg synthoid/day because my hypothyroid symptoms were so irksome, such as weight gain (even tho I bike ~7000 mi/year, with no snacks, low sugar/salt and minimal processed foods, GF, etc); severe constipation, and being tired. Metabolism slows if my TSH numbers get higher than about 1.5. Everyone is different, but I do best with levels near 0.4. It is important not to be in hyperthyroid range. I've been hypothyroid for +20 years and my metabolism is best for me with higher doses of synthoid. Doctors early in my diagnosis had me at TSH levels close to 5 and that was extreme lethargy and weight gain. BTW, I've had celiac for 14 years, but likely have been subclinical or gluten intolerant my whole adult life because of symptoms that went away after GF, such as skin rashes, GI problems, reflux, and feeling tired. I sometimes wonder if I went GF 50 years ago if I would have fewer autoimmune diseases now.