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Obesity means you have an amount of body fat that may harm your health. Having too much body fat can lead to
type 2 diabetes,
high blood pressure,
sleep apnea, and
Because of these risks, it is
important to lose weight even if you don't feel bad now. It is hard to change
eating habits and exercise habits. But you can do it if you make a plan.
You can use a
measurement called a body mass index, or BMI, along with your waist size, to decide 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, unhealthy eating patterns,
and too little physical activity, your extra weight is putting your health in
Interactive Tool: Is Your BMI Increasing Your Health Risks? to find out
your body mass index.
Use the Interactive Tool: What Is Your Child's BMI? to check BMI in children ages 2 to 19.
carry too much fat around the middle, rather than around the hips, are more
likely to have health problems. In women, a
waist size of 35 in. (88 cm)
or more raises the chance for disease. In men, a waist size of
40 in. (101 cm) or more raises
the chance for disease.footnote 1
If you are Asian, your health may be at risk if you have a BMI of 27.5 or
higher and you have unhealthy eating patterns
and too little physical activity. Also, health
problems are seen with a smaller waist size. In Asian women, a waist size of
32 in. (80 cm) or more raises
the chance for disease. In Asian men, a waist size of
36 in. (90 cm) or more raises
the chance for disease.footnote 2
Check this table to find your risk for disease using your body mass index and waist size.
When you take in more
calories than you burn off, you gain weight. How you eat, how active you are,
and other things affect how your body uses calories and whether you gain
If your family members are obese, you may have inherited
a tendency to gain weight. And your family also helps form your 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
foods are often high in saturated 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.
Focus on health, not diets.
Diets are hard to stay on and usually don't work in the long run. It is very
hard to stay with a diet that includes lots of big changes in your eating
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% of your body weight can make a
difference in your health.
Make a plan for change. Work with your doctor to create a plan that will work for you.
Ask family members and friends for help in keeping with your plan. Ask your
doctor to recommend a dietitian to help you with meal planning.
When you stray from your plan, don't get upset. Figure out what got you
off track and how you can fix it.
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 stay on 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.
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 more, 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 and at bookstores.)
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. Keep track of when you eat beyond feeling full and if you eat for reasons other than being hungry. 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. Use the
Interactive Tool: How Many Calories Did You Burn? to see how many
calories you burn through daily activities.
and medicines don't work by themselves. Most people also need to make changes
in what they eat and how active they are.
Before your doctor will
prescribe medicines or surgery, he or she will probably want you to work on
healthier eating and activity for at least 6 months. Even if your doctor gives you
medicines or recommends surgery, you will need to keep your new healthy habits
for the rest of your life.
Learning about obesity:
Living with obesity:
Health Tools help you make wise health decisions or take action to improve your health.
Obesity is a
complex disease for which no single cause or cure exists. You gain weight when
you take in more calories than you burn off. But obesity is influenced by many
other things, including:
Other things influence your weight and whether you are physically active,
obesity affects your health depends on many things,
including your age, gender, where you carry your body fat, and how physically
active you are.
If you are obese and have unhealthy eating or activity habits, you have a higher risk for
gallstones, type 2 diabetes,
high blood pressure,
high cholesterol and
coronary artery disease (CAD),
a stroke, and
sleep apnea, among other conditions.
Children who are obese are at risk for many of the same long-term health problems.
If you have healthier habits or lose
weight, your risk for these conditions is reduced.
If fat builds up mostly around your stomach (sometimes
called apple-shaped), you are at greater risk for type 2 diabetes, high blood
high cholesterol, and coronary artery disease than
people who are lean or people with fat around the hips (sometimes called
pear-shaped). Your waist size affects your risk of health problems.
Research shows the
following health benefits for weight loss:
Along with a regular medical
checkup, you may have some tests to check on your health.
doctor may want to do blood tests to check for
type 2 diabetes,
thyroid or liver problems, and
high cholesterol or
high triglyceride levels.
will check your blood pressure, ask about any medicines you are taking, and
discuss your medical history and your family's medical history. He or she will
ask how active you are, whether you drink alcohol (and how much), your history
of weight gain, and how often you have tried to lose weight.
waist size along with your
body mass index (BMI) can help your doctor check your
type 2 diabetes and
coronary artery disease (CAD).
Tests are available to estimate your body fat percentage (to find out about how much of your weight is fat). This is different from your BMI. With some of these tests, you may also learn your basal metabolic rate (BMR). Knowing your BMR can help your doctor or registered dietitian plan how many calories you need each day.
Doctors use BMI to help screen for unhealthy weight. If you have a BMI of 30 or higher, your extra weight-as well as unhealthy eating patterns and too little physical activity-may be putting your health in danger. If you are Asian, your health may be at risk with a BMI of 27.5 or higher.footnote 2
Interactive Tool: Is Your BMI Increasing Your Health Risks? to find your
If you have concerns that your child is overweight or at risk of becoming so, ask your doctor to review your child's growth charts and medical history with you. If your child's BMI and growth pattern suggest a weight problem, your doctor will give your child an exam to look for problems that can cause weight gain. He or she may ask questions about eating and exercise habits. Regular checkups will also be important over time.
Use the Interactive Tool: What Is Your Child's BMI? to find out the BMI of your child age 2 or older.
obesity will be most successful if you create a
long-term plan with your doctor. A reasonable goal might be to begin making
lifestyle changes by increasing physical activity and eating healthy foods. Your initial goal should be to improve your health, not to achieve an
a goal of losing 10% of your body weight in 6 months.footnote 1 Doctors often recommend that people make lifestyle changes for at least 6 months before trying
medicines or surgery.
Your doctor may also
counseling. If you use food to cope with depression,
loneliness, anxiety, or boredom, you need to learn new skills to deal with
Eating fewer calories
while increasing activity is the best way to lose weight. Focus on smaller portion sizes.
See ChooseMyPlate for the amount of food you should eat.
People often convince themselves that they don't
overeat. Keeping a food journal(What is a PDF document?) can help you find out how many calories you consume in a day. Then you can set a goal with your doctor or dietitian according to your needs.
Limiting your calories to very low levels might seem like the way to quick weight loss. But it can have serious negative effects on your body and your ability to keep the weight off.
Limiting calories and portion size-not limiting the types of
foods you eat-causes more weight loss over the long term. For example, cutting only carbohydrate
or fat will not cause any more weight loss than a healthful eating plan.
Rather than focusing
on a particular type of diet, try to eat healthier foods. Don't try to restrict
the foods you love. Eat less of them. Eat smaller portions.
Take a look at the dietary guidelines for good health.
dietitian can show you how to make healthy changes in
your eating habits and help you recognize your hunger signals. For more information, see the Weight-Loss Strategies and Programs section of this topic.
activity helps you burn more calories. Overall, experts recommend doing moderate or vigorous activity
to get and stay healthy.
One of the best ways to increase your
activity is by walking.
Keep track of your steps with
a step counter phone app or pedometer. If you have a desk job, you may be surprised to
see how little you move in a typical day. Start with a goal of
increasing your steps by 2,000 steps a day and work up to 10,000 to 12,000.
To find out how many calories are burned during various
activities, use the
Interactive Tool: How Many Calories Did You Burn?
For more information on exercise and fitness, see the topic
Fitness: Getting and Staying Active.
See your doctor after 6
months to check your progress. Some people stop losing weight around this time,
because their bodies adjust to fewer calories and their motivation starts to
At this point your doctor may want you to increase your
activity and revisit the dietitian to make further changes to your eating habits. Your
goals may switch from losing more weight to keeping the weight off. Staying
active is very important.
If you have
lost weight but gained it back, don't be discouraged. It is not uncommon to try
several times before weight comes off and stays off. Talk to your doctor about
starting again. It may be helpful to work with others who are trying to lose
weight by following a structured program.
If you do
not lose weight, continue to gain weight, or have lost weight several times
only to regain it, or if your doctor is concerned about a
related health problem, you might need to try
medicines or surgery.
Most weight-loss programs can help you lose weight at first. But you will lose
more and have more health benefits if you can keep with it for a longer time.
You need to find the right balance of
eating and physical activity that you can keep doing or a program that works
with your lifestyle.
Before you begin treatment,
decide if you are ready to make the lifestyle changes needed to lose weight.
Losing weight and keeping it off can be hard. Think
about successes that you had before and how you were able to achieve them.
If you are
ready to make a plan for healthier eating, your doctor may suggest losing 10% of your weight at a rate of
1 lb (0.45 kg) to
2 lb (0.9 kg) a week as your
first target. It is better that you maintain a small amount
of loss rather than lose a lot of weight fast and gain it back.
Research shows that people who keep track of what they eat
and drink each day have more success at losing weight:
Keep up with your physical activity.
Think ahead about situations that may be
hard. Ask yourself if you are eating for reasons other than hunger:
Many commercial weight-loss programs (such as
Weight Watchers or Lifesteps) and self-help or support groups (such as
Overeaters Anonymous) are available. The quality and effectiveness of
programs vary widely, from reputable obesity clinics associated with hospitals
to quick weight-loss schemes that may even harm your health with untested
considering a weight-loss program, ask
questions about the staff's qualifications and whether counseling is offered.
Be aware that the advertising strategies for weight-loss programs and products,
such as using celebrities and "before and after" pictures, are usually
Most weight-loss medicines for
obesity work by making you feel less hungry or making
you feel full sooner. They are used together with healthy eating habits and exercise.
Medicine is generally used only for those who have a
body mass index (BMI) of 30 or higher. But they
sometimes are used for those with a BMI of 27 or higher who are at risk for
high blood pressure,
coronary artery disease,
type 2 diabetes, and
sleep apnea.footnote 1
work for everyone. And medicine alone is not as effective as when it is combined with
healthy eating habits or activity.
Nonprescription weight-loss products
aren't recommended. Some have dangerous side effects, and others have no
Surgery may be an option if you have a
body mass index (BMI) of 40 or more. It may also be an option if you have a BMI of 35 and another health
problem related to your weight.
Interactive Tool: Is Your BMI Increasing Your Health Risks? to calculate
Experts are still debating whether surgery for obesity is okay for children.
The goal of surgery is to cause
significant weight loss. This should reduce
obesity-related health problems, including type 2
high blood pressure.
Surgery can help you lose weight in a couple of ways. Restrictive operations (such as adjustable gastric band ) reduce how much food you can eat by making the stomach smaller. Malabsorptive operations (such as Roux-en-Y gastric bypass) make it harder for your body to digest and absorb food.
It is important to
remember that you may still be obese or overweight after the surgery. Also,
surgery will require you to make extreme changes in how you eat, such as eating
only a few ounces of food at a time because the surgery creates a much smaller
After surgery, you
will need to learn new ways to eat. You'll need to eat very slowly and
chew your food well. You will not be able to drink for 30 minutes before eating, during your
meal, and for 30 minutes after eating. If you don't make these changes, you may vomit frequently
and have pain. You may also develop nutrition problems.
Your doctor may recommend calcium, iron, and
All surgeries have risks. Discuss your treatment options
with your doctor to decide what is best for you.
Most people who
have surgery to treat obesity begin to lose weight quickly. Weight loss usually
continues for about 2 years.
Risks common to all surgeries for
weight loss include an infection in the incision, a leak from the stomach into
the abdominal cavity or where the intestine is connected (resulting in an
peritonitis), and a blood clot that blocks blood flow
in the lung (pulmonary embolism). Some people develop
It is important to
compare the risks of being obese with the risks of surgery.
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ByHealthwise StaffPrimary Medical ReviewerE. Gregory Thompson, MD - Internal MedicineKathleen Romito, MD - Family MedicineMartin J. Gabica, MD - Family MedicineAdam Husney, MD - Family MedicineSpecialist Medical ReviewerRhonda O'Brien, MS, RD, CDE - Certified Diabetes Educator
Current as ofNovember 16, 2017
Current as of:
November 16, 2017
E. Gregory Thompson, MD - Internal Medicine & Kathleen Romito, MD - Family Medicine & Martin J. Gabica, MD - Family Medicine & Adam Husney, MD - Family Medicine & Rhonda O'Brien, MS, RD, CDE - Certified Diabetes Educator
To learn more about Healthwise, visit Healthwise.org.
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