Endocrine disorders such as Cushing's syndrome and hypothyroidism may cause weight gain and exacerbate metabolic dysfunction in obesity. Other forms of endocrine dysfunction, particularly gonadal dysfunction (predominantly testosterone deficiency in men and polycystic ovarian syndrome in women), and abnormalities of the hypothalamic-pituitary-adrenal axis, the growth hormone-IGF-1 system and vitamin D deficiency are common in obesity. As a result, endocrinologists may be referred people with obesity for endocrine testing and asked to consider treatment with various hormones. A recent systematic review and associated guidance from the European Society of Endocrinology provide a useful evidence summary and clear guidelines on endocrine testing and treatment in people with obesity. With the exception of screening for hypothyroidism, most endocrine testing is not recommended in the absence of clinical features of endocrine syndromes in obesity, and likewise hormone treatment is rarely needed. These guidelines should help reduce unnecessary endocrine testing in those referred for assessment of obesity and encourage clinicians to support patients with their attempts at weight loss, which if successful has a good chance of correcting any endocrine dysfunction.