Being obese means having so much body fat that your health is in danger. Too much body fat can lead to type 2 diabetes, heart disease, high blood pressure, arthritis, sleep apnea and stroke.

Because of these risks, it is important to lose weight even if you do not feel bad now. It is hard to change eating habits and exercise habits. But you can do it if you make a plan.

How do I know if I’m obese?

You can use a measurement called a body mass index, or BMI, to learn whether your weight is dangerous to your health. The BMI is a combination of your height and weight. If you have a BMI of 30 or higher, your extra weight is putting your health in danger.

Where you carry body fat may be as important as how many extra pounds you have. People who carry too much fat around the middle, rather than the hips, are more likely to have health problems. In women, a waist size of 35 inches (88.9 cm) or more raises the chance for disease. In men, a waist size of 40 inches (101.6 cm) or more raises the risk for disease.

What causes obesity?

When you take in more calories than you burn off, you gain weight. Eating habits and activity levels, among other factors affect the way your body uses calories and determines whether or not you gain weight.

If your family members are obese, you may have inherited a tendency to gain weight. Your family also helps form eating and lifestyle habits, which can lead to obesity.

Also, our busy lives make it harder to plan and cook healthy meals. For many of us, it's easier to reach for prepared foods, go out to eat, or go to the drive-through. But these food choices are often high in fat and calories. Portions are often too large. Work schedules, long commutes and other commitments also cut into the time we have for physical activity.

There is no quick fix to obesity. To lose weight, you must burn more calories than you take in.

I’ve tried diets, but I always gain the weight back. What can I do?

Focus on health, not diets. Diets are hard to maintain and usually do not work long term. It is very hard to stick with a diet that includes lots of big changes in your eating habits.

Instead of a diet, focus on lifestyle changes that will improve your health and achieve the right balance of energy and calories. To lose weight, you need to burn more calories than you take in. You can do it by eating healthy foods in reasonable amounts and becoming more active. And you need to do it every day.

Little steps mean a lot. Losing just 10 pounds (4.5 kg) can make a difference in your health.

Make a plan for change. Work with your doctor to develop a plan that will work for you. Ask family members and friends to help you stick with your plan. Ask your doctor to recommend a dietitian who can help you with meal planning.

When you stray from your plan, do not get upset. Figure out what got you off track and how you can fix it.

How can I stick with all the changes?

It is hard to change habits. You have to be ready. Make sure this is the right time for you. Are you ready to make a plan and stick to it? Do you have the support of your family and friends? Do you know what your first steps will be? Becoming healthier and staying that way is a lifelong effort.

Most people have more success when they make small changes, one step at a time. For example, you might eat an extra piece of fruit, walk 10 minutes longer, or add more vegetables to your meals.

Studies show that people who keep track of what they eat are better at losing weight. Keep a notebook where you can write down everything you eat and drink each day. You may be surprised to see how much you are eating. Use a calorie counter to add up your calories. (You can find calorie counters online, at bookstores and as mobile device applications.)

As you keep track of calories, look at whether you skip meals, when you eat, how often you eat out, and how many fruits and vegetables you eat. This will help you see patterns that you may want to change.

You may want to write down the amount of physical activity you've had each day and compare the calories you burned to those you took in.

Can I take medicines or have surgery?

Surgery and medicines do not work by themselves. Most people also need to change their eating habits and levels of activity.

Before your doctor will prescribe medicines or surgery, he or she will probably want you to work on diet and activity for at least six months. Even if your doctor prescribes you medication or recommends surgery, you will need to stick with your new healthy habits for the rest of your life.