Obesity and Hypertension: Mechanisms, Risks, and Treatment

You don’t have to be a cardiologist to know that hypertension is a major concern in the U.S. and around the world. 120 million U.S. adults have hypertension, or what the lay public generally calls high blood pressure. 93 million fall into the category of uncontrolled hypertension.

If we want to address the growing problem of hypertension, we would do well to start with obesity. Obesity and hypertension are inextricably linked, and this life-threatening combination affects even children.

The Relationship Between Obesity and Hypertension

Obesity has historically been defined as having a body mass index (BMI) of 25 or more. As of 2025, a new definition of obesity factors in waist circumference and body fat percentage. It also separates people into clinically obese and non-clinically obese categories. Those with hypertension would automatically be considered clinically obese since they have a secondary diagnosis.

Hypertension means that systolic blood pressure exceeds 140 mmHg and/or diastolic blood pressure exceeds 90 mmHg. To make a diagnosis, these levels must be measured on two different days and exceed the limits on both days. The WHO estimates that 46% of adults who have hypertension are unaware of it. This is a serious problem since it is a major cause of premature death, yet many of the people living with it are missing out on simple lifestyle changes that could make a difference.

Around three-fourths of primary hypertension cases can be attributed to obesity. The prognosis for individuals with obesity-related cardiovascular diseases is generally poorer compared to those without obesity. However, early intervention, comprehensive management strategies, and sustained lifestyle changes hold the potential to improve outcomes and reduce the burden of cardiovascular morbidity and mortality.

Further complicating the subject, obesity is closely associated with other cardiovascular risk factors such as type 2 diabetes and obstructive sleep apnea. Together, any combination of these comorbidities poses an increased threat to the heart.

How Obesity Contributes to Hypertension

There are several ways in which body weight affects blood pressure. Broadly speaking, when the body carries extra weight, the heart has to work harder. Increased oxygen and nutrient demands increase cardiac output. Fat distribution, however, is an important factor in the development of hypertension.

Visceral fat, in particular, increases intra-abdominal pressure, putting greater demands on organs. For instance, excess visceral fat around the kidneys puts extra pressure on them, as well as on the renal veins, lymph vessels, ureters, and renal parenchyma. The strain hinders kidney function and further increases blood pressure.

Obesity causes the expansion and remodeling of adipose tissue. These changes contribute, in turn, to vascular dysfunction and cardiovascular diseases. White adipose tissue is associated with greater harm to the vasculature, compared with brown adipose tissue. Research has been done in mice showing that converting white fat to brown relaxes blood vessels and lowers blood pressure. Within brown fat, leptin and adiponectin are molecules closely linked to hypertension.

For these reasons, losing weight can reduce hypertension. There is much more detail on how obesity causes high blood pressure in our Obesity Algorithm.

Health Implications of Having Both Obesity and Hypertension

It is well understood that obesity raises the risk for heart disease. Obesity is a potent risk factor for cardiovascular morbidity and mortality. Early intervention and sustained efforts to address obesity are crucial for maximizing the potential for cardiac recovery and preventing long-term cardiovascular complications. Obesity can also lead to heart failure—even in the absence of hypertension.

Both obesity and hypertension raise the risk of other diseases, including kidney disease, metabolic syndrome and type 2 diabetes, sleep apnea, and deep vein thrombosis. Type 2 diabetes is of special concern, due to the intricate relationship between body weight, insulin resistance, and cardiovascular health. Around 70% of people with obesity have insulin resistance, defined as fasting blood glucose of 100 mg/dl or higher. It can presage type 2 diabetes by 10 to 15 years.

Losing weight with insulin resistance is more difficult because the body stores excess blood sugar as fat. High blood pressure can be a signal that someone is insulin resistant. Keep in mind that some blood pressure medicines, including beta blockers, are linked to insulin resistance, further complicating the picture.

Assessing the Risk of Hypertension in Patients with Obesity

Early diagnosis of non-clinical (or metabolically healthy) obesity can allow for intervention before it progresses to hypertension and other conditions. Monitoring a wide range of metabolic indicators like BMI, waist circumference, blood glucose, A1C, cholesterol, and blood pressure can be informative. Watch for trends over a person’s life to notice when any of these indicators moves into clinical territory.

Obesity often begins in childhood or adolescence. In children, BMI is considered along with age and sex to diagnose overweight or obesity. (The CDC provides a pediatric BMI calculator.) Obesity has a genetic component, so it’s a good idea to monitor the BMI of children whose biological parents or siblings have the condition. Children with hormonal conditions or certain rare diseases, like Prader-Willi syndrome, are also more prone to overweight and obesity.

Pediatric obesity has been increasing for the last 30 to 40 years, and with it, pediatric hypertension. Some estimates say that 15% of U.S. children live with abnormal blood pressure. According to Johns Hopkins, if a child’s blood pressure is at or above the 90th percentile, you should test it three times and do so manually with a cuff and stethoscope. Then, repeat the test in six months. If average blood pressure measures at or above the 95th percentile from multiple readings over several visits, the child can be diagnosed with hypertension.

Certain populations are at greater risk for both obesity and hypertension. Black Americans and Latinos tend to experience obesity at higher rates. High-risk groups also include children and adults who:

● Live in poverty and/or in under-resourced communities

● Live in an obesogenic environment

● Belong to a minority or underrepresented group

● Have immigrated from outside the U.S.

Socioeconomic factors play an outsized role in risk for the whole range of metabolic diseases.

Treating Hypertension in Patients with Obesity

Treating patients with obesity and hypertension starts with effective communication. When discussing these topics, it is important to approach patients with empathy, respect, and a non-judgmental attitude. Assess the person’s knowledge, perceptions, concerns, and goals. Use simple, clear language and confirm their understanding.

Strive for a comprehensive and individualized treatment plan, collaborating when possible with other medical disciplines like cardiology, nutrition, and endocrinology.

Exercise

Exercise is an ideal starting point since it addresses many of these interrelated conditions simultaneously. However, the inverse is also true. Both obesity and hypertension can make exercise a challenge. A person may have to carefully monitor their heart rate and breathing to prevent overexertion. Further complications may arise from joint pain exacerbated by excess body weight. This is where empathy and individualized planning come into play. Still, nearly anyone can benefit from even mild to moderate aerobic exercise.

Nutrition

Generally speaking, you can approach nutrition advice much the same as you would with anyone living with obesity. Encourage a high intake of whole grains and vegetables while limiting saturated fat and empty calories. Some diets, such as the Mediterranean diet or plant-based diets, may appeal to certain individuals. Encourage them to choose an approach they can stick to. While some dieters are tempted to try intermittent fasting, this practice may pose risks to someone taking blood pressure medication.

Even in patients with resistant hypertension, a combination of weight loss, aerobic activity, and healthful eating can improve blood pressure. However, medications and surgery are also potential options.

Medication

The range of available weight loss medications is expanding rapidly, and these may help a person reduce blood pressure as they lose weight. GLP-1 medications show promise in this area. For example, in a clinical trial, tirzepatide (Mounjaro) significantly lowered the systolic blood pressure of nearly 500 adults with obesity over 36 weeks. Avoid phentermine, an older and still widely used medication, which lists high blood pressure as a side effect. Combining it with topiramate, as in the drug Qsymia, is specifically contraindicated.

Bariatric surgery

Bariatric surgery is typically recommended for individuals with a BMI 35 or higher if they also have a significant obesity-related health issue, such as hypertension—as opposed to a BMI of 40 for obesity alone. It could be an option for the right patient.

The OMA is Here to Help

The OMA is here to equip healthcare professionals with the knowledge, tools, and strategies essential for understanding, preventing, and managing obesity and heart disease. Together, we foster healthier outcomes and enhance the overall well-being of individuals and communities.

Check back later in 2025 for details of our fall seminar, which will address some of the issues discussed in this article. Join our mailing list to ensure you receive announcements about this and other events.

Continue to build your knowledge of treating obesity by becoming a member of the OMA.