Is Obesity Different in Asian Americans? Expert Q&A

Medically Reviewed by Brunilda Nazario, MD on September 08, 2023
6 min read

Obesity is a medical condition that’s found everywhere. It’s nearly three times as common worldwide as it was in 1975, according to the World Health Organization. 

In the U.S., almost 42% of U.S. adults have obesity, CDC data show. But it’s less common among Asian Americans. Some experts have suggested that the standard definition of obesity – having a BMI of 30 or higher – might not be the best fit for Asian Americans.

In this interview, Jennifer Ng, MD, a certified obesity medicine specialist in New York City and chair of the Obesity Medicine Association’s Outreach Committee, discusses how obesity affects Asian Americans and what they need to know about this condition. This interview was edited for length and clarity.

WebMD: How did you get interested in obesity medicine?

Ng: When I started practicing medicine, many of the patients I saw had elevated BMI, and this was across different socioeconomic classes. I was very surprised. This wasn’t something I was aware of when I was in medical school or residency. Medical school didn’t equip me to handle this or tell me how to counsel patients. It’s frustrating when you’re trained to be the person giving the answers and you just have no answers. I wanted to learn more.

WebMD: How do obesity rates within the Asian American community compare to other demographics?

Ng: The obesity rate among Asian Americans is roughly 11%, which is lower compared with many other ethnicities. Under the current criteria, a body mass index (BMI) of 25 and above is considered overweight and 30 and above is considered obesity, and that’s applied across the board.

But there’s concern that we may not be capturing the full spectrum of the issue because BMI and the standard for measurement for obesity and being overweight is based on people of European descent. 

There are some differences between ethnicities that we need to be cognizant of. Some guidelines suggest that perhaps we should consider Asian Americans to be overweight and having obesity at a lower BMI – a BMI of 23 and above for being overweight and 25 and above for having obesity – because there seems to be an increased prevalence of cardiovascular disease and metabolic disease at a lower body weight among Asian Americans. 

WebMD: Do overweight and obesity rates differ between different subpopulations of Asian Americans?

Ng: Different subgroups within the Asian community can have different rates of being overweight or having obesity. For example, Filipino Americans and South Asians tend to have a higher rate compared to East Asians. I will say that things change depending on how long you’ve lived in this country. Higher BMI seems to be associated with living in the United States longer. 

WebMD: When we use a standard like BMI that’s based on one population of people like Caucasians or those of European descent and then generalize those findings across all populations, what do we potentially miss? 

Ng: We want to make sure we don’t apply one standard to everyone because people are different. People of different ethnic backgrounds are at different risks. When we use only one standard, sometimes we under-diagnose or under-screen certain populations or overdiagnose or over-screen other populations. 

WebMD: How does this impact the Asian American population?

Ng: There’s a lot of misconception out there. I have a lot of Asian Americans that come into my office who don’t think that being overweight and having obesity is an Asian problem because there is a tendency for Asian Americans to run on the thinner side, they don’t have a family history, or they don’t eat a Western diet. They may think they don’t need to exercise or worry about their diet. 

Primary care doctors may not be aware either and they may under-diagnose or under-screen Asian American patients. 

WebMD: Why do Asian Americans experience cardiovascular and metabolic disease at a lower BMI compared to other populations?

Ng: You can gain fat in different ways. The size of the fat cell can increase, or the number of fat cells can increase. There’s genetic variation in how people store fat. It seems that, especially in the South Asian community, there’s a tendency for fat cell size to increase, which appears to be more problematic than increasing the number of fat cells. The fat becomes “sick” and starts to produce inflammatory markers and abnormal hormones, which can lead to a lot of the issues we see with metabolic disease. 

There’s some thought that within the East Asian and South Asian community, there’s an increased tendency to store fat as visceral fat too. It’s the more dangerous fat that is stored in and around the organs. Our organs aren’t equipped to store fat, so they then become dysfunctional. That can lead to increased cardiovascular disease, metabolic syndrome, diabetes, and cholesterol issues.

For example, if you store more fat in the liver, it leads to inflammation because the fat produces inflammatory markers and interrupts the functioning of normal liver cells. This can lead to problems metabolizing cholesterol, glucose, and fat. If your glucose control is impaired because your liver isn’t working properly, your pancreas starts to release more and more insulin. That can lead to diabetes, and insulin itself causes fat cells to grow. 

WebMD: Aside from genetics, what else seems to be driving the rates of overweight and obesity among Asian Americans? Do diet and exercise among Asian Americans play a role?

Ng: Diet and lifestyle certainly play a role, but so do environmental factors. If people work a lot, live far from work, don’t have the opportunity to eat healthy food, and aren’t physically active, it becomes problematic. The diet that may have worked for them before moving to America, where they were more active and less sedentary, might not be OK here. 

There are misconceptions about exercise among my patients of Asian descent, especially the older ones who didn’t grow up in America. They say, “This isn’t something that Asian people do. It’s too much. It’s too intense.”

WebMD: How do you counsel your Asian American patients?

Ng: Every patient is different. I’m a primary care doctor, so when they come to me, I assess their overall health, diet, and exercise and see where they are. Regardless of BMI or weight, I educate them on healthy diets and exercise. 

When I see patients of Asian descent in my office, I am more vigilant. I do use the lower BMI criteria to counsel my patients and to start checking symptoms to consider whether they could be at risk for cardiovascular or metabolic disease. I also use waist circumference to evaluate patients because BMI doesn't always accurately tell you about body composition. Waist circumference can be a better marker of visceral fat, which is a more concerning risk factor for cardiovascular and metabolic disease.

You don’t want to alienate your patient. You want them to come back. I try to meet them where they are because you can’t bulldoze over them and their culture. I’ll suggest tai chi, which is a gentle exercise that helps build balance and strengthen muscles, or bodyweight exercises like carrying their groceries. I’ll suggest trying brown rice or wild rice or cutting down on portions. Little changes are better than no changes.

WebMD: What do you want Asian Americans to know? What message do you have for them?

Ng: My main message is just because you’re thin or in the normal range of the standard BMI criteria, it doesn’t mean that you’re not at risk. It’s still important to eat healthy, exercise, and see your doctor regularly. Many conditions are reversible if you catch them early enough, even if you have a genetic predisposition. There are changes you can make to your diet or lifestyle that can impact obesity and other disease risks.