Overweight vs. Obese: Definitions and Health Effects

Overweight and obesity are two different health conditions involving weighing more than what you and your provider determined is right for you. Obesity is a more severe form of excess body fat and is considered a chronic (long-term) health condition. Being overweight means carrying more weight than is recommended, but it has fewer health risks.

The fastest way to measure your weight is through your body mass index (BMI). However, BMI can be inaccurate. Other methods, including body fat percentage, waist circumference, waist-to-hip ratio, and skinfold thickness, can help you better understand your weight and body composition.

While weight alone doesn’t tell the full story, combining it with other measurements, like body fat percentage or waist size, can offer a more accurate picture of your overall health. There are several ways to measure whether you may be overweight or experiencing obesity.

Body Mass Index (BMI)

The BMI for being overweight is between 25-29.9, and for obesity, it is greater than 30.

To determine your BMI, your healthcare provider will measure your weight and height. Then, they divide your weight by your height squared to get your BMI.

Here are the steps you would follow using pounds and inches to calculate BMI:

• Determine your weight in pounds 
• Find your height in inches
• Square your height in inches (or multiply it together)
• Divide your weight in pounds by your squared height in inches
• Take the sum from the previous step and multiply it by 703
• The result is your BMI

Using this formula, if you weigh 185 pounds and are 72 inches tall (72 x 72 = 5,184), your BMI would be 25. If you want to use kilograms and meters for weight and height, you wouldn’t need to multiply by 703.

Body Fat Percentage (BFP)

Body fat percentage is the percentage of total weight that comes from fat. For example, if you’re 150 pounds and 30% is fat, you have 45 pounds of body fat. A healthy range is around 21–32% for people assigned female at birth and 8–20% for people assigned male at birth.

BFP gives a better picture of your health than weight alone, since it distinguishes between fat and muscle. Two people with the same BMI can have very different body fat percentages.

Various tools measure BFP, including:

• Bioelectrical impedance: Electrical currents are used to find out the amount of body fat by measuring the resistance the current encounters as it passes through the body.
• DEXA scans: These are imaging scans that measure the amount of calcium and other minerals in the body.
• Hydrostatic weighing: Also known as hydrodensitometry, it measures how much the body weighs in water versus out of water. The difference in weight can help find out the percentage of body fat.

Waist Size (Waist Circumference)

Your waist circumference is the measurement around the abdomen, just above the belly button. A waist larger than 35 inches for people assigned female at birth or 40 inches for people assigned male at birth can result in a higher risk of health problems like heart disease, diabetes, and metabolic syndrome, a group of conditions affecting metabolism. Research suggests higher abdominal (visceral) fat is related to health challenges, even if your weight seems normal.

Waist-to-Hip Ratio (WHR)

The waist-to-hip ratio (WHR) compares the size of the waist to the size of the hips to estimate the amount of fat throughout your body. You divide your waist measurement by your hip measurement. A result over 0.85 for people assigned female at birth and 0.90 for people assigned male at birth means you carry more fat around your abdomen, raising the risk of health conditions like diabetes.

Skinfold Thickness

This method utilizes special tools called calipers to estimate body fat percentage by measuring the fat just under the skin in specific areas of the body, such as the triceps, abdomen, or thighs. Results can vary depending on the individual’s skill level in performing the test.

A skinfold thickness test is best for tracking changes in subcutaneous fat—the layer of fat just below the skin—over time.

Experts estimate that nearly one in three adults is overweight, and more than two in five adults experience obesity. A significant number of adults in the United States are at risk for health issues like type 2 diabetes and heart disease. These conditions can also negatively impact fertility and mood, as well as increase the risk of certain cancers.

Common health risks associated with overweight and obesity include:

• Diabetes: Being overweight or obese can raise the risk of developing type 2 diabetes. However, research has found that reducing weight by 5-10% and increasing physical activity to 150 minutes per week helps lower these risks by more than 50%.
• Heart conditions: Obesity increases the risk of several different heart conditions. These include coronary artery disease, high blood pressure (hypertension), heart failure, dyslipidemia (high levels of fat in the blood), and atrial fibrillation, which causes irregular and rapid heartbeats.
• Stroke: Being overweight or obese may raise the risk of strokes by up to 78%.
• Cancer: One study found a connection between being overweight and obesity and new cases of cancer, 28,000 in men and 72,000 in women.
• Fertility challenges: People with obesity may experience infertility and lower success rates during in vitro fertilization(IVF). This could be a result of inflammation, insulin resistance, and hormonal imbalances due to obesity.
• Mood disorders: Being overweight or obese may increase the risk of having anxiety or depression. Studies show a strong relationship between weight and major depressive disorder.
• Pregnancy complications: Studies show that 60% of people who experience being overweight or obesity while pregnant have a higher risk of complications like a C-section, miscarriage, stillbirth, premature birth, blood clots, and more.

Healthcare providers determine severe overweight or obesity based on BMI ranges:

• Overweight: This ranges from 25-29.9 with a low risk of severe complications. Maintaining a healthy weight through a balanced diet and regular exercise remains crucial.
• Class 1 obesity: This ranges from 30-34.9 with a low severity risk.
• Class 2 obesity: This ranges from 35-39.9, with a moderate risk of severity.
• Class 3 obesity: Also known as morbid obesity, ranges from 40 to greater. At this stage, the risk of developing certain health conditions is high.

Experts usually recommend losing 5-10% of body weight to lower the severity of these conditions. Losing 5% of your weight may significantly improve your health by reducing your risk for heart disease, diabetes, and kidney and liver conditions.

A healthcare provider tailors treatment for overweight individuals and those with obesity based on age, body type, activity level, and risk factors. Depending on preferences and goals, your healthcare provider may recommend a combination of lifestyle changes, medication, and, in some cases, weight loss surgery.

Diet Changes

Changing your weight often involves making different food choices, such as prioritizing heart-healthy foods like fruits, vegetables, whole grains, lean meats, and healthy fats. Some people find it useful to follow a nutritious diet plan like the Mediterranean diet or the DASH diet.

Physical Activity

Experts recommend 150 minutes of moderate-intensity exercise or 75 minutes of high-intensity exercise per week. Your healthcare provider can advise you on what is best for you and help you work towards these goals.

Sleep Modifications

Research shows that not getting enough sleep may increase the risk of obesity. Prioritize sleep and aim for approximately seven to eight hours of sleep each night.

Behavioral Therapy

When you eat, your brain releases chemical messengers, like dopamine (the feel-good hormone). Some people experience stronger chemical reactions when eating than others, which may result in overeating or cravings. This may explain why some individuals struggle more with managing their weight. A weight management plan that includes speaking to a mental health professional may be helpful.

Prescription Medications

If dietary changes and physical activity aren’t helping, your healthcare provider may recommend prescription weight loss medications. These medications, along with lifestyle changes, can help you maintain your weight loss once you stop taking them.

Surgeries and Other Procedures

In more severe cases of obesity, a healthcare provider may recommend devices like a gastric balloon, a gastric band, or surgery to help with weight management. Bariatric surgeries involve reducing the size of the stomach or bypassing part of the digestive system. 

Being overweight and obese are common challenges in the U.S. A BMI for being overweight is between 25-29.9, and a BMI for obesity is greater than 30. Having a higher BMI than recommended may raise the risk for a number of health conditions, including heart disease, diabetes, fertility issues, certain cancers, and more.

A healthcare provider can put together a weight management plan with you. These plans typically include lifestyle changes, sleep modifications, and behavioral therapy. In severe cases, they may include prescription medications and even surgery, especially if lifestyle changes aren’t helping on their own.