Your waist size is an important indicator of your health. Larger waist sizes are linked with increased risks of chronic diseases and sometimes premature death.1

Average Waist Size for Women 

According to the Centers for Disease Control and Prevention (CDC), the average waist size is 38.5 inches (98 centimeters) for women older than 20 in the United States.2

The Centers for Disease Control and Prevention. Body Measurements.

 This represents an increase of roughly two inches since the 1990s, reflecting broader trends in rising rates of obesity and metabolic conditions.3

Waist size also changes across a woman's lifespan. Younger women typically have smaller waists, while older women often see their waistlines increase. Hormonal shifts, particularly decreases in estrogen and progesterone during menopause, can change fat distribution in the body, leading to more fat stored around the midsection.4

This natural process is one reason why postmenopausal women are more likely to meet the criteria for abdominal obesity, even if their weight has not changed dramatically.

Potential Health Implications

Waist size can vary greatly among women. For example, a taller woman would naturally have a larger waist measurement than a shorter woman with the same proportions. To adjust for this, some doctors use the waist-to-height ratio, which considers how your waist size compares to your overall body height.5 

Even with these adjustments, waist circumference on its own is a powerful predictor of health.1

Abdominal obesity in women is typically defined as having a waist size of 35 inches (88 centimeters) or more.1 The average waist size of women in the U.S. is above this threshold, which means that many women fall into the category of abdominal obesity, regardless of their body mass index (BMI).

Body mass index, or BMI, uses your weight and height to make assumptions about body fat, and by extension, your health. This metric does not factor in your body composition, ethnicity, sex, race, and age. The medical community still uses BMI to analyze health data.

Abdominal obesity is strongly associated with excess visceral fat, which is the fat stored around your internal organs, such as your liver, pancreas, and intestines. Visceral fat can increase your risk of conditions, including:67

• Heart disease
• Type 2 diabetes
• High blood pressure
• Stroke

Several studies show that waist size is a stronger predictor of health outcomes than BMI is. For example, one large analysis of multiple studies found that women with abdominal obesity had a significantly higher risk of death from any cause compared to those below the threshold.8

Interestingly, even women with a “normal” BMI but a large waist had elevated health risks, according to other research.1

This means you can be at a healthy weight by BMI standards but still be at risk if you carry most of that weight around your midsection. That's why many experts now encourage people to look at waist circumference with BMI rather than relying on BMI alone.8

How To Measure and Interpret Waist Size 

It's simple to measure your waist at home. Common mistakes include pulling the measuring tape too tightly, leaving it too loose, or assuming your belly button marks the correct waistline. Following the proper technique ensures consistency and accuracy. Here's how:5

• Locate the right spot: Find the top of your hip bones and the bottom of your ribs to help you locate your waist at the midpoint.
• Place the tape: Position a flexible measuring tape around this spot, which is usually just above your belly button.
• Breathe normally: Wrap the tape snugly (but not tightly) around your waist, exhale normally, and take the measurement.

BMI is often the first measurement people look at to compare weight versus height, but it has limitations. Waist circumference offers an additional layer of insight because it reflects fat distribution rather than just overall body mass.1 

Waist Size and Body Image

While waist size is an important health metric, it should not be confused with self-worth or beauty. Societal standards, often set by media and fashion industries, can create unrealistic expectations around body size and shape. These standards can cause stress, negative body image, and even disordered eating behaviors.910

Health looks different on every body. Genetics, body composition, and natural variation all play roles in waist size. Consider waist size measurement as one tool among many for understanding your health.

Setting personal goals, such as improving fitness, eating more whole foods, or reducing waist circumference gradually if you have a larger waist size, can be more motivating and sustainable than striving for a so-called ideal body measurement.