Background: Obesity, diabetes mellitus may be related to the health, the relationship and
the physiological capacity of the production of thyroid hormones (TH), triiodothyronine (T3) and
Objectives: The main aims of this review are to describe the relationship between obesity, appetite, weight
management, hormonal mechanisms of diabetes mellitus and hypothyroidism post-bariatric surgery.
Methodology: An in-depth literature search was conducted to identify scientific studies, which analyzed
the correlation between diabetes mellitus and hypothyroidism post-bariatric surgery.
Results: Bariatric surgery decreases hypothyroidism, reduces the need for pharmacological action (such
as levothyroxine), controls the weight and body fat and increases the sensitivity to leptin and insulin.
Conclusion: The reduction of the stomach and intestine by bariatric surgery is an evolutionary and
beneficial action, because it may lead to a drastic decrease on numbers of conditions such as diabetes,
obesity, hypothyroidism, and others. Thus, new studies should also focus on patients’ post-operatory
conditions, such as lifetime, regulation and functioning of organs after reduced nutrition, and consumption
and delivery of nutrients to health maintenance.