Obesity is a disease characterized by having excessive body fat, increasing a person’s risk for many serious health problems, such as heart disease, diabetes, and even some cancers.
Obesity is a disease characterized by having excessive body fat, increasing a person’s risk for many serious health problems, such as heart disease, diabetes, and even some cancers. In the United States, obesity is a growing health crisis affecting children and adults alike.
Though obesity is a complex health challenge, it can often be treated with a combination of lifestyle changes and, in many cases, surgery or weight loss medication.
Obesity has become a common health problem. It affects about one in five children and two out of five adults in the U.S., according to the Centers for Disease Control and Prevention (CDC).
The World Health Organization (WHO) reports that obesity rates have more than doubled worldwide since 1990 and that currently, around 890 million people live with obesity. These obesity statistics have corresponded with increases in the rates of type 2 diabetes and other obesity-related health concerns.
Obesity can limit your ability to exercise, interfere with sleep, and contribute to high blood pressure (hypertension) and higher levels of cholesterol and blood sugar (glucose). Carrying excess weight can also put extra burden on your knees and other joints, raising the risk of arthritis and other mobility issues.
The terms “obesity” and “overweight” are sometimes used interchangeably, but there are some key differences.
To sort out the overweight versus obesity question, understand that overweight is a condition that means you have more body weight than what’s considered healthy or normal by medical standards. But it doesn’t necessarily put your overall health at great risk.
Obesity, on the other hand, is a chronic disease and a risk factor for a range of health conditions. Directly or indirectly, it might require management and attention over the course of a person’s life.
The National Heart, Lung, and Blood Institute defines obesity as a body mass index (BMI) of 30 or more. BMI is a measurement of body fat based on a person’s height and weight.
An overweight BMI is between 25 and 29.9. While BMI is a widely used gauge of fitness and body composition, it’s not a perfect tool.
An athlete who’s especially muscular, for example, may have a higher BMI than their peers who are the same height but weigh less because they have less lean muscle mass.
Curious about your BMI? Put your height and weight into the Hers BMI Calculator.
Obesity symptoms can differ greatly from one person to another. But most symptoms show up because bodily systems have to work harder due to the excess weight.
Some of the more common symptoms of obesity:
Fatigue and reduced energy
Joint pain
Reduced exercise endurance and excessive sweating
Shortness of breath
Snoring and poor-quality sleep
Obesity can also lead to emotional or psychological problems, like loneliness, low self-esteem, and depression. This isn’t always the case, of course, as lots of folks with obesity have many close friendships, active social lives, and a positive outlook on life.
Unfortunately, the psychological complications of obesity can sometimes prevent a person from taking the steps needed to address the issue.
For instance, those with depression are often less likely to stay physically active, which, in turn, can worsen symptoms of depression and obesity. But time and time again, research has shown that physical activity is one way to treat obesity and improve depressive symptoms.
Obesity is a disease with many potential causes and contributing factors.
The main cause is one you’ve probably heard many times before: consuming more calories than you expend. In other words, your intake of calories has to at least equal or be less than the calories you burn.
Otherwise, those excess calories turn into excess body fat. Consuming fewer calories than you burn is known as a calorie deficit, and it’s essential to achieving your weight loss goals.
Unhealthy weight gain is often a result of environmental factors and everyday eating habits. A typical American diet tends to emphasize large portions, which, unsurprisingly, contributes to excess calorie consumption.
Likewise, eating mostly foods packed with saturated fat or added sugars, or that are generally high in calories and low in nutrition, can contribute to obesity or an overweight BMI.
A sedentary lifestyle (meaning most of the day is spent sitting) that doesn’t include regular exercise or other physical activity might also lead to obesity.
Certain genetic conditions can also cause obesity.
For example, Prader-Willi syndrome is an inherited disorder that leads to, among other complications, intellectual disability, a short stature, and constant feelings of hunger, which contribute to obesity.
Some medical conditions can cause obesity.
Cushing syndrome, for instance, is a rare endocrine disorder that causes fat to accumulate throughout much of the body, especially around the face, neck, and trunk, though the limbs are often slender. Polycystic ovary syndrome (PCOS) is another condition that can lead to overweight and obesity.
Obesity risk factors can be genetic or environmental — the latter has to do with lifestyle choices and things you don’t have as much control over, like illness or work stress.
You might inherit certain genes that predispose you to weight gain. Coupled with unhealthy eating habits and little to no physical activity, the risk for obesity increases.
For childhood obesity, in particular, risk factors include:
Meals and snacks with too many processed foods or other unhealthy options
Lack of access to parks and other recreational spaces
Little or no school-related physical activity programs
Too much sedentary time, especially involving video games and other screen-based activities
Obesity risk factors for both children and adults include not getting enough sleep and stress.
Too little shut-eye can affect hunger-related hormones, making you snack at odd times and crave high-carbohydrate foods. Poor sleep can also lead to daytime sleepiness, which could interfere with your energy levels and desire to exercise.
Too much stress is another obesity risk factor, as higher levels of the stress hormone cortisol can lead to overeating and affect how fat is stored in the body. Stress can also interfere with a good night’s sleep and lead to unhealthy behaviors, like excess alcohol consumption, which can contribute to obesity too.
An elevated BMI is the first and most widely used indicator of obesity. If you’re concerned you’ve put on weight, it’s helpful to know when your BMI indicates you have overweight (25 to 29.9) or obesity (30 and higher).
Because children and teens are still growing and their bodies are changing, the CDC has a specific BMI calculator for kids ages two to 19. It takes into consideration sex and age, as well as height and weight.
Other ways to measure body fat include measuring waist circumference and calculating waist-to-hip circumference ratios.
Is obesity a disease that should be treated like other chronic illnesses? Yes.
Like any chronic disease, obesity treatment is best managed by a healthcare provider. In some cases, it might be a team of healthcare professionals that includes a primary care physician and a registered dietitian or nutritionist who can develop healthy meal plans and assist you on your weight loss journey.
A weight loss plan will almost always include physical activity. Working with a personal trainer or taking exercise classes can be helpful, particularly if the instructor has experience working with individuals with obesity.
Your workout routine should include aerobic or cardio exercise (anything that gets your heart pumping), as well as strength training. Replacing body fat with lean muscle mass will also help you burn calories more efficiently, even when you’re not exercising.
A healthy weight loss program calls for healthy eating, but that doesn’t just mean reducing calorie intake. Meals and snacks should be nutritious, helping you feel full and energized.
You may want to set a goal weight within the healthy BMI range, then establish realistic short-term and long-term weight loss goals.
Talk with your healthcare provider about the amount of weight you want to lose (or should lose) to reduce health risks. Then come up with a plan of action to reach that target.
The National Institutes of Health recommends a slow but steady approach to weight loss. For most adults, losing one to two pounds a week is a good pace.
No matter your starting weight, the goal should be sustainable weight loss rather than rapid weight loss. Fad diets that emphasize foods you don’t like or require you to follow an unrealistic eating plan won’t help with weight management.
For some people with obesity, weight loss surgery (also known as bariatric surgery) may be one way to accelerate weight loss and launch a new approach to eating.
Generally, bariatric surgery is recommended for those with a BMI of 40 or higher or a BMI of at least 35, plus another serious health problem, such as diabetes.
Obesity treatment may also include medications that help support weight loss, such as GLP-1 agonists (semaglutide, Wegovy®, Ozempic®). These medications reduce feelings of hunger to help you lower your calorie intake and slow the movement of food from the stomach to the small intestine, so you feel fuller longer.
To prevent obesity or avoid weight gain after you’ve already lost weight, try to adopt habits that make maintaining a healthy weight easier.
This means eating more vegetables, fruits, complex carbs like whole grains, healthy fats like avocado and olive oil, and lean proteins.
Also, try to stay physically active. The American Heart Association recommends getting at least 150 minutes of moderate-intensity aerobic exercise a week, which works out to roughly 30 to 40 minutes most days of the week.
Other obesity prevention tips:
Ask family members or friends to join you in your healthy lifestyle. Having an accountability partner to exercise with can be motivational. And cooking healthy meals with others can be fun and educational, especially when you share your favorite nutritious, low-calorie recipes.
Move more throughout the day. Setting aside 30 to 60 minutes a day for exercise is helpful. But you can also benefit from taking short walks, stretching, and any activity that gets your muscles moving.
Get more sleep. Aim for seven to nine hours of sleep a night to improve physical and mental wellness.
Limit unhealthy foods. This includes refined grains, sweets with added sugar, soda, alcohol, and high-glycemic foods (white potatoes, white rice, etc.)
Reduce and manage stress. To boost your overall well-being, lower stress through activities like meditation and breathing exercises.
Don’t hesitate to get medical advice if you want to lose weight but aren’t sure where to start. A healthcare provider can suggest lifestyle changes and potentially weight loss medication.