If you suspect obesity, first you should obtain a focused history in the physical. History may reveal symptoms like joint pain, snoring, fatigue, and dyspnea, as well as mood symptoms such as depression. Additionally, the patient might present with obesity-related comorbidities, such as metabolic syndrome, diabetes mellitus, hypertension, and dyslipidemia. On the other hand, physical exams will reveal excess adipose tissue and a larger waist circumference, and some patients may also have abdominal stretch marks, acanthosis, nigricans, and lower extremity edema. Okay, the next step is to calculate the BMI using the patient's weight in kilograms and height in meters. If the BMI is 25 to 29.9, the patient is overweight. If the BMI is between 30 and 34.9, the patient falls under class 1 obesity. Between 35 and 39.9 is class 2 obesity, and finally, a BMI greater than or equal to 40 is class 3 obesity. Here's a clinical pearl for you. Though the diagnosis of obesity hinges on BMI, keep in mind that it's an imperfect individual measure. In fact, certain racial and ethnic groups, such as those with ancestry from some parts of Asia, may experience complications of obesity at lower BMI's, while others with higher BMI's, but low at a positive rate, have a lower risk of these complications.