I heard that a friend received a diabetes diagnosis during a routine check-up. Everyone was surprised because this person has always been slim and avoids sugary foods.

They thought, "I have no weight, so I shouldn't have diabetes." However, I learned that this situation is surprisingly common among Asians.

This is often referred to as "lean diabetes." Today, I want to calmly outline the numbers and criteria.

First, let's discuss BMI. It's an obesity indicator calculated from height and weight, and in the U.S., a BMI of 25 or higher is typically considered overweight. When I calculated it for my height, I found that just a few extra pounds would quickly push me over 23.

However, the American Diabetes Association (ADA) uses a separate threshold of 23 for Asian Americans. This guideline was established in a position statement in 2015 and has continued in clinical guidelines since then.

Specifically, it states that if your BMI is 23 or higher and you have any risk factors, you should consider testing regardless of age. Risk factors include family history, high blood pressure, lack of exercise, and being part of a high-risk ethnic group for diabetes.

Thus, for Asians, it can be said that simply exceeding a BMI of 23 makes one a candidate for testing. Even if your weight is normal, the ADA recommends starting testing at age 35.

The U.S. Preventive Services Task Force (USPSTF) has slightly different criteria. Their 2021 recommendation advises testing for overweight or obese adults aged 35 to 70.

In this case, they only added that Asians should consider the BMI of 23, but it was not included in the official recommendations. When comparing the two guidelines, the differences are quite clear.

The ADA recommends testing for Asians with a BMI of 23 and at least one risk factor, or for anyone starting at age 35. The USPSTF's baseline is overweight individuals aged 35 to 70, with 23 being a reference point.

Why is there a separate criterion? A study supported by the NIH analyzing data from the 2011-2012 National Health and Nutrition Examination Survey (NHANES) provides an answer.

This study found that the diabetes prevalence among Asian Americans was 21%. Even more surprising is that 51% of Asians with diabetes were unaware of their condition.

It was reported that this group had the highest rate of undiagnosed cases. It's shocking to think that half of them were unaware, and I sat there for a while, stunned by the numbers.

In the same survey, the average BMI for Asians was below 25, while the overall average for the U.S. was just under 29. This indicates that many people may appear slim but have high blood sugar levels.

There are also differences within the Asian population. According to estimates released by the CDC, the combined diabetes rate for diagnosed and undiagnosed individuals was 23% for South Asians, 22% for Southeast Asians, and 14% for East Asians.

So why do lean individuals develop diabetes? Researchers often point to visceral fat accumulating deep in the abdomen.

According to one review paper, East Asians have a larger area of visceral fat compared to whites, even with the same waist circumference. This visceral fat is linked to insulin resistance.

Another factor is the function of pancreatic beta cells that produce insulin. A study focusing on Indian populations found that lean young diabetes patients had a significantly reduced ability to secrete insulin.

However, researchers do not conclude that this cause applies uniformly to all Asians. The honest conclusion is that this issue is still not fully resolved.

Now, let me make a critical point. I believe that the weight-centered testing criteria have subtly fostered the misconception that "you must be overweight to be at risk."

A 2023 study by a Northwestern University research team also pointed out that relying solely on weight criteria misses many Asians. Their analysis indicated that testing everyone aged 35 to 70, regardless of weight, identifies more patients.

However, there's no need to wait for the criteria to change. The testing itself is simpler than you might think. Most of the time, it just involves a single blood draw.

You can choose from fasting blood sugar, hemoglobin A1C, or an oral glucose tolerance test. If the results are normal, it's generally recommended to retest every three years.

If I were you, I would definitely ask to include the A1C test during this year's annual check-up. Many times, it is covered as a preventive test by Medicare or workplace insurance, so check with your insurance provider.

Measuring your waist circumference is also a good habit. Sometimes, the number on the scale doesn't tell the whole story about your body as honestly as your waist measurement does.

If you have a family history or are already taking blood pressure medication, I urge you to act quickly. The timing and method of testing can vary for each individual, so be sure to consult with your doctor or pharmacist.

Being slim is certainly a good thing. However, I am reminded that it does not guarantee health.

When was the last time you had your blood sugar tested? Which criteria resonate more with you, the BMI or age guidelines? Please share your thoughts in the comments.