Who this is for
Get your height and weight measured and your BMI calculated at least once a year, and if the number is 25 to 34.9, ask for a waist circumference as well. That is the position of the 2013 AHA/ACC/TOS guideline, the only body on this page that says who should be measured and how often. It labels both instructions expert opinion.
USPSTF does not tell you who gets measured. Its 2018 statement says screening "is now part of routine clinical practice" and reviewed what happens after the number is known: adults 18 or older with a BMI of 30 or higher should be offered or referred to intensive, multicomponent behavioral interventions, a Grade B recommendation. If that is you, the question is not whether to be weighed but whether you have been offered the program.
If your BMI is 25 to 29.9, the two bodies part. USPSTF's graded recommendation leaves you out, because the trials it reviewed had a median BMI above 33 and it could not separate the effect in participants who were overweight from those with obesity. AHA/ACC/TOS says weight-loss treatment is indicated in overweight adults who also carry an indicator of cardiovascular risk, naming diabetes, prediabetes, hypertension, dyslipidemia and elevated waist circumference. Adults at a healthy weight are advised to avoid weight gain.
One adjacent USPSTF position belongs here: it publishes a separate recommendation on blood glucose screening for adults who are overweight or have obesity, with its own age band, and our type 2 diabetes screening page carries that row with its current date. A BMI of 25 or higher is a reason to read it.
Where the recommendations diverge
- USPSTF 18 and older
- ACC / AHA Not age-bounded Not age-bounded
- ACC / AHA Not age-bounded Not age-bounded
The USPSTF recommends that clinicians offer or refer adults with a body mass index (BMI) of 30 or higher (calculated as weight in kilograms divided by height in meters squared) to intensive, multicomponent behavioral interventions.
Our note: USPSTF did not review screening itself. Its Scope of Review: "Because screening for obesity is now part of routine clinical practice, it was not a focus of this review." No sentence on the page states how often anyone should be measured. The statement updates the 2012 recommendation on screening for obesity in adults. Overweight (BMI 25 to 29.9) is excluded because the trials' median BMI was above 33. An update is in progress (merged into behavioral counseling to prevent cardiovascular disease, Final Research Plan November 2, 2023, no draft recommendation had posted as of September 10, 2026).
Measure height and weight and calculate BMI at annual visits or more frequently.
Our note: 2013 AHA/ACC/TOS guideline, Table 4, recommendation 1a: NHLBI Grade E (Expert Opinion), ACC/AHA Class I, Level of Evidence C. Box 17 of its treatment algorithm restates the interval ("at least annually in all patients") and says the follow-up intervals "are not evidence based". No age band is stated. Dated from the Circulation publication (2013 Nov 12); the JACC co-publication is 2014. The guideline is not listed on ACC's current Guidelines index (checked September 10, 2026) and no page formally retires it; AHA's index could not be read.
Measure waist circumference at annual visits or more frequently in overweight and obese adults.
Our note: Same guideline, Table 4, recommendation 1d: NHLBI Grade E (Expert Opinion), ACC/AHA Class IIa, Level of Evidence B. Box 4 narrows the population: a waist measurement is recommended at BMI 25 to 34.9 and called unnecessary at 35 or higher, where it "will add no additional risk information". Cutpoints, by expert opinion: more than 88 cm (35 in) for women and more than 102 cm (40 in) for men. No age band is stated. Same 2013 date and currency caveat as the BMI row.
Why they differ
The two bodies are not answering the same question, and that gap is larger than any difference in thresholds.
- USPSTF (2018) graded a referral, not a measurement. In its own scope statement: "Because screening for obesity is now part of routine clinical practice, it was not a focus of this review." Its 2012 statement was a recommendation on screening for obesity in adults; the 2018 update dropped the word, and no sentence on the page states how often anyone should be weighed.
- AHA/ACC/TOS (2013) does say who and how often: BMI at annual visits or more frequently in all patients, and waist circumference at the same interval in adults with overweight or obesity. Both rows are NHLBI Grade E, expert opinion (ACC/AHA Class I, Level of Evidence C for BMI; Class IIa, Level B for waist). The guideline says so itself: "Although these follow-up intervals are not evidence based, they are a reasonable compromise between the need to identify weight gain at an early stage and the need to limit the time, effort, and cost of repeated measurements."
So the only screening interval on this page dates from 2013 and is rated as opinion, and the only recent Grade B is about what to do once the number is 30. The categories are on firmer ground than the cadence: the same 2013 guideline grades the use of 25 to 29.9 for overweight and 30 or higher for obesity to identify adults at elevated cardiovascular risk as A (Strong). What is opinion is the yearly visit, not the cutpoints.
The bodies also differ on the overweight range. USPSTF explains its exclusion: "Although some trials included participants who were overweight, the average BMI in the majority of trials was in the obese range (median BMI, >33). Therefore, the USPSTF was unable to examine the differential effects of interventions among participants who were overweight or had obesity." AHA/ACC/TOS indicates weight-loss treatment at a BMI of 30 or higher, or 25 to 29.9 with an additional risk factor.
Two things have moved since these dates. First, the 2013 guideline is not on ACC's current guideline index (checked September 10, 2026: the index lists its 2013 lifestyle sibling and files ACC's 2025 obesity document under Concise Clinical Guidance, with no obesity entry under Guidelines). We found no page that formally retires it, and we could not read AHA's index. Second, that June 20, 2025 ACC document is an expert consensus from ACC alone, not an ACC/AHA guideline; by ACC's own description such documents "provide recommendations where none currently exist". It sets no screening interval. What it changed is the order of treatment: "Whereas prior guidelines suggested a trial of lifestyle intervention prior to pharmacotherapy, data from phase 3 trials evaluating semaglutide and tirzepatide show minimal additional weight loss when combined with intensive behavioral therapy/lifestyle intervention. Patients should not be required to “try and fail” lifestyle changes prior to initiating pharmacotherapy; nonetheless, lifestyle interventions should always be offered in conjunction with NuSH therapies." The prior guideline it cites there is the 2013 document. USPSTF's 2018 pharmacotherapy position sits on the other side: it "encourages clinicians to promote behavioral interventions as the primary focus of effective interventions for weight loss in adults", and the drugs it reviewed were liraglutide, lorcaserin, naltrexone and bupropion, orlistat and phentermine-topiramate; semaglutide and tirzepatide do not appear on its page.
USPSTF is updating. The topic has been merged into a broader behavioral counseling update whose Final Research Plan (November 2, 2023) covers "Adults with high BMI (i.e., ≥25.0 kg/m2) or other adiposity-related risk factor", so the next statement's scope reaches the overweight range that 2018 left out. A separate topic on preventive medications for chronic weight management is planned. As of September 10, 2026 no draft recommendation has posted; this page is re-verified when it does.
For context only: a Lancet Diabetes & Endocrinology Commission (January 2025) proposes restricting BMI to screening and confirming obesity with at least one further measure (waist circumference, waist-to-hip or waist-to-height ratio, or direct fat measurement), except above a BMI of 40, where excess adiposity "can be pragmatically assumed". A commission convened by a journal sets policy for no professional body, and none of the bodies on this page has adopted its clinical versus preclinical distinction as a screening criterion.
USPSTF's 2018 page also records positions we have not quoted from the bodies' own documents, so they appear as no rows here: it describes AAFP as recommending screening for obesity in all adults with referral at a BMI of 30 or higher, and AACE and ACE as recommending BMI screening with waist circumference as a supplement above a BMI of 35.
What the test involves
Weight and height are measured in light clothing or an exam gown with no shoes, the BMI is calculated, by hand as weight in kilograms divided by height in meters squared or by the electronic record, and the result is documented in your chart. That is the 2013 AHA/ACC/TOS procedure. CDC's online calculator does the arithmetic and is for adults 20 and older (page dated June 26, 2024).
At a BMI of 25 to 34.9, AHA/ACC/TOS adds a waist measurement "to provide additional information on risk", with more than 88 cm (35 in) for women and more than 102 cm (40 in) for men as the marks of increased cardiometabolic risk. It calls the measurement unnecessary at a BMI of 35 or higher, where the waist "will likely be elevated and will add no additional risk information". ACC's 2025 document prints the same marks as 35 and 40 inches or greater, adds a waist-to-height ratio of 0.50 or greater, and lists separate waist values for South Asian, Chinese and Japanese populations: 31.5 in for women and 35.5 in for men in the first two, and 35.4 in for Japanese women and 33.5 in for Japanese men.
On cadence, AHA/ACC/TOS is specific: for adults who have never been overweight or whose weight is stable, a 1-year interval; for adults with overweight or obesity, or at a normal weight with a history of overweight, "more frequent monitoring may be appropriate". USPSTF sets no cadence.
If the result is abnormal
A BMI of 30 or higher: under USPSTF (2018) you should be offered or referred to an intensive, multicomponent behavioral intervention. The programs behind that grade were designed to reach or hold a 5% or greater weight loss through dietary change and increased physical activity; most lasted 1 to 2 years, most had 12 or more sessions in the first year, and they centered on problem solving, self-monitoring of weight, peer support and relapse prevention. USPSTF attributes the 5% mark to the FDA, which "considers a weight loss of 5% as clinically important".
AHA/ACC/TOS (2013) frames the goal differently: an initial target of 5% to 10% of starting weight within 6 months, while telling adults with cardiovascular risk factors that even a sustained 3% to 5% loss produces clinically meaningful benefits. Those are different numbers for different purposes, a benefit floor and a program goal, not one figure.
Medication thresholds, a BMI of 30 or higher or 27 or higher with a weight-related condition, appear in AHA/ACC/TOS, in the Endocrine Society's 2015 pharmacotherapy guideline (recommendation 1.2, which names hypertension, dyslipidemia, type 2 diabetes and obstructive sleep apnea as qualifying conditions) and in the FDA label as ACC quotes it in 2025. That is one label threshold the guidelines adopt, not three independent findings. Where they differ is sequencing: the 2013 guideline considers medication once a comprehensive lifestyle intervention has not produced or held weight loss, with an allowance for starting both together in people whose history already shows that pattern, and ACC's 2025 consensus says patients should not be required to try and fail lifestyle change first. Surgical referral in the 2013 guideline starts at a BMI of 40, or 35 with obesity-related conditions, with the footnote that "This does not mean that all patients who meet the criteria should have surgery."
Whatever the BMI, the guidelines treat it as the first number, not the last. AHA/ACC/TOS asks for additional personal risk assessment within each category "because degree of risk can vary", and the risk indicators it names when it decides who needs treatment are diabetes, prediabetes, hypertension and dyslipidemia: blood pressure, A1c or fasting glucose, and a lipid panel are the measurements behind them.
More on this screening
Frequently asked questions
My BMI is 27. Does any of this apply to me?
Not under USPSTF's graded recommendation, which starts at 30 and says why: the trials it reviewed had a median BMI above 33. Under AHA/ACC/TOS (2013) it does: measure your waist, and if you also have diabetes, prediabetes, hypertension, dyslipidemia or an elevated waist circumference, weight-loss treatment is indicated. USPSTF's pending update is scoped to a BMI of 25 and above, so its answer may change when the draft posts.
How often should my BMI be checked?
At least once a year, at annual visits or more frequently, per AHA/ACC/TOS (2013). That is expert opinion, and the guideline itself says the interval is not evidence based. USPSTF sets no interval and did not review screening at all in 2018. No other body on this page publishes an interval at all.
Is BMI accurate for me?
As a screen, yes; as a diagnosis, no body on this page treats it as one. CDC says BMI does not distinguish fat from muscle and bone or show where fat is carried, and calls it a screening measure to be considered with other factors. AHA/ACC/TOS adds waist circumference at a BMI of 25 to 34.9 for that reason. The cutoffs also shift by population: USPSTF cites an adjusted cut point of greater than 25 for Asian Americans, and ACC (2025) prints overweight at 23 and obesity at 25 for Asian populations.
Do I have to try diet and exercise before medication?
That depends on which document your clinician follows, and they were written twelve years apart. The 2013 AHA/ACC/TOS guideline considers medication once a comprehensive lifestyle intervention has not worked, and USPSTF (2018) encourages behavioral interventions as the primary focus. ACC's June 2025 expert consensus says the opposite on sequencing, citing semaglutide and tirzepatide trials that showed minimal additional weight loss from combined lifestyle therapy, while still requiring that lifestyle interventions be offered alongside. USPSTF has a separate medication topic planned and no draft yet.