GLP-1 BMI Requirement Calculator

For brand-name GLP-1 medications approved for weight management, the BMI requirement is 30 or higher, or 27 or higher with at least one weight-related condition. That is the practical reading of both FDA labels (semaglutide and tirzepatide), and it is worth knowing where each part comes from.

The indication itself uses words, not numbers. The brand-name semaglutide weight-management label and the brand-name tirzepatide weight-management label both cover chronic weight management in adults with obesity, or adults with overweight in the presence of at least one weight-related comorbid condition, alongside a reduced-calorie diet and increased physical activity. The numbers come from the approval trials described in each label’s Clinical Studies section, which enrolled adults with a BMI of 30 or higher, or 27 to under 30 with a weight-related condition. The National Institute of Diabetes and Digestive and Kidney Diseases states the same two thresholds for weight-management medications generally.

The semaglutide weight brand is also approved for adolescents 12 and older with obesity, which is defined differently for children and teens. This calculator covers adults only.

Where BMI 25 to 27 Fits

By the Centers for Disease Control and Prevention definition, overweight starts at a BMI of 25.0 and obesity at 30.0. The brand-name weight-management approval trials enrolled overweight adults only from a BMI of 27, so a BMI of 25 to 27 sits inside the CDC’s overweight range but below what those trials studied. If you want your BMI category on its own, with its limits spelled out, use the BMI calculator, with its limitations spelled out.

A weight-related condition is a health problem that excess weight causes or worsens. The approval trials enrolled adults in the 27 to 30 range who had at least one weight-related condition, such as high blood pressure, high cholesterol (dyslipidemia), obstructive sleep apnea, or cardiovascular disease.

The calculator above asks about five: high cholesterol, fatty liver disease, high blood pressure, obstructive sleep apnea, and prediabetes or type 2 diabetes (an A1c of 5.7% or higher). Selecting one changes what this calculator shows; it does not establish that you meet the label criteria. A physician confirms any diagnosis and whether it applies.

No. The brand-name semaglutide diabetes label covers blood sugar control in adults with type 2 diabetes, plus reducing cardiovascular risk and kidney disease progression in adults with type 2 diabetes. It has no BMI criterion because it is not approved for weight management. The qualifying requirement is a type 2 diabetes diagnosis.

The same applies to the brand-name tirzepatide diabetes label, which covers type 2 diabetes. When either is prescribed for weight loss alone, that is off-label use. Semaglutide and tirzepatide are also sold under separate brand names approved for weight management, which is why those labels carry the BMI criteria.

BMI is one part of whether you may be within the approved population. It does not decide whether a medication is safe for you. Both brand-name weight-management labels carry a boxed warning for thyroid C-cell tumors, seen in rodents, with unknown relevance to humans, and both are contraindicated for anyone with a personal or family history of medullary thyroid carcinoma or MEN 2 (multiple endocrine neoplasia syndrome type 2).

A physician also reviews other medications, history of pancreatitis or gallbladder disease, kidney function, pregnancy plans, and eating-disorder history, among other things. That review is the step no calculator can do, and it can end in a no.

What the Trials Found

In the approval trials, which enrolled adults meeting these BMI criteria, participants taking semaglutide lost an average of 14.9% of body weight over 68 weeks (STEP-1, New England Journal of Medicine, 2021), and participants taking tirzepatide lost an average of 15.0% to 20.9% over 72 weeks depending on the dose studied (SURMOUNT-1, New England Journal of Medicine, 2022). These are averages of the brand-name products with wide individual variation, not predictions. The GLP-1 weight loss calculator shows them as a range for your weight.

Both molecules are also available as compounded preparations, prepared by a licensed compounding pharmacy against an individual prescription. Compounded medications are not FDA-approved, are not generic versions of brand-name GLP-1 medications, and have not been through the trials described above.

The brand approvals don’t transfer. A compounded preparation has no FDA-approved indication, so the label criteria on this page describe the brand-name products, not compounded ones. Compounded tirzepatide is not approved for sleep apnea, and compounded semaglutide is not approved for cardiovascular risk reduction. The FDA explains its position in FDA’s concerns with unapproved GLP-1 drugs used for weight loss.

Protocol MD sells compounded semaglutide and compounded tirzepatide. We are saying so here, in the section that describes them, so you can read it with that in mind. Protocol MD does not sell brand-name GLP-1 medications. If you can access or afford one, it carries an evidence base and a set of approvals that compounded versions do not.

Protocol MD is a physician-guided telehealth practice. A licensed physician reviews your intake, history, and current medications, and decides whether treatment is appropriate. Nothing is prescribed on the basis of a BMI or a calculator, and a physician can decline.

For patients a physician determines are appropriate candidates, Protocol MD prescribes compounded semaglutide or tirzepatide. Compounded medications are not FDA-approved, are not generic equivalents of, and are not the same product as, brand-name GLP-1 medications. If you are planning meals around weight loss, the protein calculator (grams per day and per meal) estimates a daily protein range.