Endocrine Dysfunction 2

How Bariatric Surgery Can Impact Endocrine Dysfunction

March 25, 2019
  • Are you feeling stressed?
  • Are you not getting enough sleep?
  • Are you feeling run down and fatigued all the time?
    Maybe this is the time to check your endocrine function!

Endocrine function is responsible for regulating many vital organs and processes in our system.  It has a significant impact on how our hormones circulate throughout our system which regulates our energy balance, metabolism, mood, growth and development, sexual function, etc.

The endocrine system affects almost every organ and cell and it closely interacts with other systems in our body. If our hormones are not in a balance or they are too high or too low, we may have endocrine dysfunction, disease or disorder. One of the most common endocrine diseases diagnosed in the USA is diabetes type 2 (Rizvi, 2016).

Obesity and Type 2 Diabetes

Type 2 diabetes currently affects about 26 million people in the United States and more than 382 million people worldwide. Obesity is a major independent risk factor for developing diabetes.

Many complications are associated with the disease, including an increased risk for cardiovascular disease. Diabetes is a leading cause of kidney and eye diseases (U.S. Department of Health and Human Services, 2018).  Diabetes arises when the pancreas does not produce sufficient insulin or when the body cannot respond to the insulin that is present.

Modest weight loss, as little as 5% of total body weight, can help to improve type 2 diabetes in patients who are overweight or obese.

The hemoglobin A1C or HbA1c test is a simple blood test that measures your average blood sugar levels over the past 3 months. It’s one of the commonly used tests to diagnose diabetes. Higher A1C levels correlate with the severity of diabetes and its complications. It’s crucial to maintain your A1C level under good control throughout life (Rizvi, 2016).

How Bariatric Surgery Can Impact Endocrine Dysfunction

Weight loss surgery, also called bariatric surgery, is a way to help people who were diagnosed with morbid obesity and unable to lose weight through various treatment options, lifestyle modifications- different diets and regular exercises. Specific criteria established by the National Institutes of Health (NIH) Consensus panel indicated that bariatric surgery is appropriate for all people with BMI (kg/m2) >40 and for patients with BMI 35-40 with an associated health condition.

Body mass index (BMI) is a measure of body fat based on height and weight that applies to adult men and women. There are a number of different types of bariatric surgery and they all work by restricting the amount a person can eat or reducing the number of calories that are absorbed from food.

Studies show that bariatric surgery may result in resolution or improvement of type 2 diabetes.

It also showed to be an effective option for improvement of other metabolic abnormalities such as dyslipidemia, hypertension and obstructive sleep apnea (Benraouane & Litwin, 2011).

Polycystic Ovarian Syndrome

Polycystic ovarian syndrome (PCOS) is the most common endocrine disorder among women of reproductive age.  Women who were diagnosed with PCOS and have undergone bariatric surgery have reported beyond weight loss-resolution of menstrual dysfunction and improvement of hirsutism (excessive hair growth) (Wilson-Perez&Seeley, 2011).

The symptoms of PCOS are remarkably sensitive to weight changes, and weight loss of as little as 5% can restore fertility (Bates&Legro, 2012).


Hypothyroidism is another common condition where the thyroid gland is underactive and doesn’t produce enough thyroid hormone.

Undiagnosed thyroid condition can lead to weight gain.

Treatment requires taking thyroid hormone pills. Some studies revealed that hypothyroidism may improve after bariatric surgery and overall improve thyroid function. Some people can have a reduction in thyroid medication dosages after bariatric surgery (Zendel et al., 2017). However, further studies are required to compare different types of bariatric surgeries and their influence on thyroid replacement therapy absorption (Laurberg et al., 2012).

Weight loss and subsequent endocrine changes after bariatric surgery contribute to a better quality of life and resolution of many chronic health conditions. Bariatric surgery is a powerful tool and subsequent weight loss after surgery is a significant incentive for many people to keep and maintain healthy lifestyle choices. The benefits of bariatric surgery must be weighed against all the potential risks for adverse effects.


  • Benraouane, F., & Litwin, S. E. (2011). Reductions in cardiovascular risk after bariatric surgery. Current opinion in cardiology, 26(6), 555-61.
  • Bates, G. W., & Legro, R. S. (2012). Long-term management of Polycystic Ovarian Syndrome (PCOS). Molecular and cellular endocrinology, 373(1-2), 91-7.
  • Holst, J. J., Madsbad, S., Bojsen-Møller, K. N., Svane, M. S., Jørgensen, N. B., Dirksen, C., & Martinussen, C. (2018). Mechanisms in bariatric surgery: Gut hormones, diabetes resolution, and weight loss. Surgery for obesity and related diseases: official journal of the American Society for Bariatric Surgery, 14(5), 708-714.
  • Rizvi A. A. (2016). The evolving role of bariatric surgery in patients with type 1 diabetes and obesity. Integrative obesity and diabetes, 2(2), 195-199.
  • Laurberg, P., Knudsen, N., Andersen, S., Carlé, A., Pedersen, I. B., & Karmisholt, J. (2012). Thyroid function and obesity. European thyroid journal, 1(3), 159-67.
  • Longitudinal Assessment of Bariatric Surgery (LABS) Consortium, Flum, D. R., Belle, S. H., King, W. C., Wahed, A. S., Berk, P., Chapman, W., Pories, W., Courcoulas, A., McCloskey, C., Mitchell, J., Patterson, E., Pomp, A., Staten, M. A., Yanovski, S. Z., Thirlby, R., … Wolfe, B. (2009). Perioperative safety in the longitudinal assessment of bariatric surgery. The New England journal of medicine, 361(5), 445-54.
  • Wilson-Pérez, H. E., & Seeley, R. J. (2011). The effect of vertical sleeve gastrectomy on a rat model of a polycystic ovarian syndrome. Endocrinology, 152(10), 3700-5.
  • Wolfe, B. M., Kvach, E., & Eckel, R. H. (2016). Treatment of Obesity: Weight Loss and Bariatric Surgery. Circulation research, 118(11), 1844-55.
  • Zendel, A., Abu-Ghanem, Y., Dux, J. et al. (2017). The Impact of Bariatric Surgery on Thyroid Function and Medication Use in Patients with Hypothyroidism. OBES SURG (2017) 27: 2000. Retrieved from: https://doi.org/10.1007/s11695-017-2616-7
Evgeniya Larionova


Evgeniya Larionova, NP, joined the Weight Loss Surgery Center team at Beth Israel Deaconess Medical Center as an outpatient nurse practitioner. Evgeniya plays a key role for the bariatric multidisciplinary team, performing post-operative clinical assessments and participating in the interdisciplinary weight loss surgery screening process. She also provides support and education to bariatric patients and their families. Evgeniya holds a master’s degree in family health nursing as well as a certification from the MGH Institute of Health Professions.