What You Need to Know About Obesity

What is obesity?

In the simplest terms, obesity is a disease characterized by having excess fat that causes health risks and is defined as having a body mass index (BMI) greater than 30.

Obesity is often divided into three categories:

• Class 1, a BMI of 30.0 to 34.9
• Class 2, a BMI of 35.0 to 39.9
• Class 3, a BMI of 40 or higher

You can calculate your BMI here.

While BMI is used to diagnose obesity, it's not a perfect tool and is just one data point. During the "Reclaim Your Wellness" webinar hosted by HealthyWomen and The Black Women's Health Imperative in February 2021, Dr. Fatima Stanford, an obesity medicine physician, scientist and educator at Massachusetts General Hospital and Harvard Medical School, pointed out, "The problem with BMI as a singular individual measure is it just tells me height and weight. It doesn't tell me what type of weight it is. Is it fat or water? Where is it distributed?"

Where a person carries their weight has implications for their health. "For example, Black women tend to carry a lot of weight in our hip, buttock and thigh region. That tends to not be as bad for our health as if we carried it in our abdominal region. Our abdominal region is around all of those really important organs, which leads to metabolic disease like diabetes or fatty liver," Stanford said.

As with many diagnostic tools, BMI should not be looked at in a vacuum.

Why is obesity often misunderstood?

Obesity is more than a simple definition. "When we look at obesity as a disease … there's a pathophysiology, meaning different parts of the brain and gut that regulate one's weight status, so it's extremely complex. People say that losing weight is not rocket science. I would say that it's actually much more complex because we have such variability between one individual to the next," Stanford said.

Despite findings that genetic, environmental and metabolic factors cause obesity, it's often viewed by society and even healthcare providers (HCPs) as the result of poor personal choices, rather than a disease. Though the American Medical Association recognized obesity as a disease in 2013, the medical establishment has yet to catch up, and most HCPs are not well educated in obesity medicine.

Because of this stigma surrounding obesity, Stanford often meets resistance from her patients to accept treatment.

"They have been told … that if only they did something better, if only they worked out an hour longer, only ate a few calories less, then they should be able to solve this issue.… The problem is that when we continue to believe that mantra … we will continue to fail at treating this most common disease," she said.

How many people are affected by obesity?

The worldwide obesity rate has almost tripled since 1975, with more than 650 million adults living with obesity, and more than 40% of American adults are living with the disease.

Racial differences do exist. Non-Hispanic Black people have the highest prevalence of obesity at 49.6%, followed by Hispanics (44.8%), non-Hispanic whites (42.2%) and non-Hispanic Asians (17.4%).

"It's important to note that the group most affected by … obesity are people like me — Black women," Stanford said.

The CDC survey found that nearly 60% of non-Hispanic Black women have obesity. While genetic factors can contribute to this difference, social and socioeconomic conditions are also responsible.

"If we look at chronic stress, Black women traditionally have the highest stress levels and experience the most racism," Stanford explained. She added that chronic stress can lead to excess fat tissue in the midsection, which increases the risk for other diseases.

Why does obesity cause or worsen other diseases?

The reasons why having obesity can cause other diseases or make the ones you have get worse are complicated, but many are related to the chronic inflammation and excess fat that go with obesity.

"Really, most major chronic diseases that people have here in the United States and around the world, unfortunately, have a significant link to obesity," Stanford said.

Here are some examples of diseases linked to obesity and some reasons for the connection:

• Heart disease: in people with obesity, an increased amount of blood needs to be pumped through the body to supply enough oxygen and nutrients to tissues. This rise in blood flow puts more pressure on artery walls, resulting in high blood pressure or hypertension. Obesity also leads to atherosclerosis, which is the buildup of fats on artery walls that form plaque, which can break off and cause a heart attack or stroke.

• Type 2 diabetes: Excess fat around the pancreas affects how it regulates blood sugar. Over time, the pancreas can no longer produce enough insulin. Excess weight also makes cells less sensitive to insulin. That causes insulin resistance, which occurs when your body doesn't use insulin well enough to lower blood sugar levels.

• Nonalcoholic fatty liver disease (NAFLD): When you have extra fat, some of it can make its way into the liver. "The liver likes to take in fat," explained Stanford. "Imagine a marbleized steak with fat strands throughout it. That's what the liver ends up looking like. The liver can't function with that amount of fat. That's why [NAFLD] is becoming the number one reason for liver transplants," Stanford said.

• Covid-19: Both obesity and Covid-19 cause inflammation in your body. "We have this kind of perfect storm," Stanford said. "When these inflammatory markers interact with each other … unfortunately, [they are likely to] worsen one's illness and significantly increase one's risk for death," Stanford explained.

What are some treatment options for obesity that people can stick with?

There are a lot of treatment options to fight obesity, but for them to be effective, they must be sustainable — meaning you can stick with them for the long run. Stanford suggests tackling one treatment at a time. "Trying to do all these things simultaneously on January 1, is probably a recipe for disaster," she said.

"Diet and lifestyle modification are always going to be our first step," she said. A well-rounded, well-balanced diet is the best choice and easier to maintain than crash or fad diets that rely on deprivation.

"We want to have lean protein, whole grains, fruits and vegetables as predominant sources of caloric value," Stanford explained.

Plans for physical activity must also be made with sustainability in mind. With a healthcare provider's help, you can begin an exercise routine that is both beneficial and doable.

Being sleep deprived or being under stress are both risk factors for obesity. An HCP may help you reduce stress and improve sleep quality and duration to help make you healthier.

While nutrition and exercise changes are enough for some people, others need to take additional steps. "Every person is different. For many, diet and exercise alone is ineffective to overcome their weight dysregulation. As such, we escalate therapy to the use of medication and surgery to help treat the severity of their disease," wrote Stanford in an email following our initial conversation.

There are different medications approved by the U.S. Food and Drug Administration for the treatment of obesity, which work in different ways. Some may lower your appetite or help you feel full faster; others may control the way the body absorbs fat.