People develop obesity when their body stores more calories than it uses over time. Your body needs calories (and essential vitamins, minerals, and other nutrients) to work properly and to be active. But if your body stores more calories than it uses, you will gain weight.

Healthy Weight

What is a healthy weight? The answer is different for everyone. But it’s important to know what a healthy weight is for you. Check out our top questions and answers on weight, weight gain, and weight loss. And talk to your doctor or nurse about your weight goals. Women often gain and lose weight differently, so the steps you need to take to lose weight may be different from the steps someone else needs to take.

Weight and obesity

Women in a classroom listening to an instructor

Two out of every three women in the United States have overweight or obesity. Extra weight leads to many diseases that affect women, such as heart disease, diabetes, and many cancers. It can be difficult to talk about your weight with a doctor or nurse. A doctor or nurse you feel comfortable with can be a powerful partner in helping you reach a healthier weight.

How do I know if I’m overweight or obese?

You can use the body mass index (BMI) to find out whether your weight is in a healthy or unhealthy range. BMI is a tool to estimate body fat. Type your height and weight into this BMI calculator.

BMI gives you a good idea of how healthy your weight is. But it doesn’t tell the whole story. BMI is less accurate in some people than in others. For example, if you are very muscular, you may be healthy even if your BMI is above 25. This is because muscle weighs more than fat.

Another way to figure out if you have a healthy weight is to measure your waist circumference (the distance around your waist). Researchers and doctors have agreed that women with a waist circumference larger than 35 inches are at higher risk for many health problems caused by overweight or obesity.

What causes obesity?

People develop obesity when their body stores more calories than it uses over time. Your body needs calories (and essential vitamins, minerals, and other nutrients) to work properly and to be active. But if your body stores more calories than it uses, you will gain weight.

Researchers know that a person’s environment over a lifetime can influence whether obesity happens. While it’s true that the food you eat is an important part of weight gain or loss, other parts of your life that you do not control can make obesity more likely. Learn more about how where you live affects weight.

What individual factors unique to me can make it more likely that I’ll gain weight?

Obesity is a complex disease that is the result of many different parts of a person’s life that happen over a long period of time. Things that can affect your weight include:

How can the place where I live make it more likely that I’ll gain weight?

Many parts of our everyday lives may make weight gain very common. These include:

Does overweight and obesity affect some women more than others?

Yes. Women of certain ages, races, and ethnicities are more or less likely than others to have overweight or obesity:

What are the health effects for women who are at an unhealthy weight?

Overweight and obesity indirectly cause millions of deaths each year. Having overweight or obesity raises your risk for many serious health problems:

Even a small amount of weight loss (3% to 5% of your body weight or less) can help lower your risk for these health problems. If you are a 160-pound woman, losing just 5 to 8 pounds, or 3% to 5% of your body weight, can make you healthier. Talk to your doctor or nurse about your risk and how much weight you may need to lose.

Does it matter where on my body I carry the weight?

Yes. Where you carry your weight makes a difference in your health. Belly fat is more dangerous for your health than fat carried elsewhere.

Women with an apple-shaped body may have a higher risk for heart disease than women with a pear-shaped body.

Apple-shaped and pear-shaped body types

Some women tend to carry fat in the belly area (apple-shaped). Other women tend to carry fat in their hips and thighs (pear-shaped). Extra weight is never healthy, but being apple-shaped increases your risk for certain health problems, such as heart disease, type 2 diabetes, and colorectal cancer, more than being pear-shaped does. That is because the type of fat your body stores in your abdomen, near your stomach, is different from the type of fat stored in your thighs and hips.

BMI tells you about how much fat you have on your body, but it does not show where you carry your weight. To measure your waist size, stand up straight and place a tape measure around your middle, just above your hip bones. Measure your waist just after you breathe out.

Most women should aim for a waist size of less than 35 inches.

Of course, this does not mean that if you carry your weight in your hips you should not worry. It’s important for all women — no matter where you carry your weight — to be physically active and eat healthy to lower your risk for health problems.

When should I talk to a doctor or nurse about my weight?

If you are worried about your weight, or if you have overweight or obesity, talk to your doctor or nurse. Your weight can raise your risk for many health problems and make it harder to get pregnant.

Your doctor or nurse may suggest healthy eating changes and more physical activity to help you reach a healthy weight.

Did we answer your question about weight and obesity?

For more information about weight and obesity, call the OWH Helpline at 1-800-994-9662 or check out the following resources from other organizations:

Underweight

Women in clinical setting

In today’s world, thinness is often praised. But being underweight, when your weight is lower than what is considered healthy for your height, can be a sign of a serious health problem. Many different things can cause women to be underweight, including eating habits, health problems, and medicines. Underweight can cause other health problems and problems getting pregnant. You can work with your doctor or nurse to help you reach a healthy weight.

How do I know if I’m underweight?

You can use the body mass index (BMI) to find out whether your weight is in a healthy or unhealthy range. BMI is a tool to estimate body fat. Type your height and weight into this BMI calculator.

Women with a BMI of less than 18.5 are considered underweight. The average woman’s height is 5 feet, 4 inches. If you weigh 107 pounds or less at this height, you are considered underweight with a BMI of 18.4. A healthy weight range for that woman would be 108 to 145 pounds.

BMI is just one way to measure healthy weight. Some women have a low, but still healthy weight. Talk to your doctor or nurse about what is a healthy weight for you.

Who is at risk for underweight?

In the United States, 1.6% of women are underweight. Women of all age groups are more likely to be underweight than men are.

What causes women to be underweight or to lose weight suddenly?

Some women are naturally thinner than others. But certain health problems, certain medicines, or other serious problems can lead to chronic (long-term) underweight or sudden weight loss. These include:

Also, there may be a link between underweight in childhood and developing an eating disorder in adolescence.

How does underweight affect a woman’s health?

Underweight raises your risk for serious health problems. Some women have a low, but still healthy weight. But if you have experienced sudden weight loss or are not eating enough to keep your body working, you may develop serious health problems, including:

Women who are underweight may also be more likely to die early than people of normal weight. Women who are underweight earlier in adulthood may also experience menopause sooner than women who stayed a normal weight.

How can I gain weight in a healthy way?

Talk to your doctor or nurse about an eating plan that can help you gain weight in a healthy way. To gain weight in a healthy way, you should focus on getting enough nutrients — calories, vitamins, and minerals — for your body to work correctly. To reach a healthy weight, you should eat foods from all of the food groups with a calorie amount that is healthy for your current weight. Your doctor or nurse can tell you how quickly to gain weight in a safe and healthy way. Gaining weight suddenly, or by eating a lot of sweet or fatty foods, is not healthy.

If you need to gain weight because of an eating disorder, work with your doctor or nurse to gain weight safely and treat the eating disorder. If the eating disorder is not treated, it may come back or continue and cause health problems. Gaining weight too suddenly, with an eating disorder, can cause serious heart problems and other health concerns.

Because many Americans are overweight, there are many resources geared toward losing weight. But some of these resources can also provide guidance for you to gain weight in a healthy way. See the list of resources at the end of this page to learn more.

Should I stop exercising if I’m underweight or losing weight too quickly?

Maybe. People who are underweight due to an eating disorder should not exercise unless their doctor tells them to. Physical activity is important for your health, muscle strength, balance, and flexibility. Your doctor or nurse can help you develop an exercise plan that is healthy and safe for a person of your current weight.

If you normally do high-intensity aerobic workouts, your doctor or nurse may talk to you about more moderate or less vigorous aerobic, strength training, and flexibility exercises.

When should I talk to a doctor or nurse about my weight?

If you are worried about your weight, talk to your doctor or nurse.

Your weight can affect your health. Your weight can also make it harder to get pregnant. Talk to your doctor or nurse if you are underweight and have period problems or symptoms of malnutrition, such as extreme tiredness, headaches, or hair loss.

Your doctor or nurse will ask you questions and may do tests to learn more about what is causing your symptoms or weight loss. Your doctor or nurse may suggest making changes in your eating and exercise habits, depending on the cause of your weight loss.

Did we answer your question about underweight?

For more information about underweight, call the OWH Helpline at 1-800-994-9662 or check out the following resources from other organizations:

Top Questions About Healthy Weight and Women (PDF, 154 KB)

Weight, fertility, and pregnancy

Doctor and patient in clinical setting

Your weight — whether too high or too low — can affect your ability to get pregnant. Being overweight or underweight can also cause problems during your pregnancy. Reaching a healthy weight can help you get pregnant and improve your chances of a healthy pregnancy and baby.

How does having overweight or obesity affect my ability to get pregnant?

Extra weight can make it hard for you to get pregnant. For example, polycystic ovary syndrome, or PCOS, is one of the most common reasons for infertility in women and can also cause obesity. Overweight and obesity affect fertility by:

How does being underweight affect my ability to get pregnant?

If you are underweight (your BMI is 18.5 or less), you may have problems getting pregnant. Being underweight can cause your body to stop making estrogen. This can cause irregular menstrual cycles. You may stop ovulating and getting your period. This is especially true if you are losing weight because you are not eating enough or because you are exercising too much, which may be signs of an eating disorder like anorexia nervosa.

In order to get pregnant, you need to ovulate or release an egg from the ovary so it can be fertilized by a man’s sperm. Then your body needs to be able to support a developing baby in the womb.

Could reaching a healthy weight help me get pregnant?

Yes. Every woman is different, but studies show that for women who have overweight or obesity, losing weight raised their chances of getting pregnant. Losing weight also helped menstrual cycles return to normal.1 Talk to your doctor or nurse about how to lose weight safely.

Women who need to gain weight before getting pregnant should gain weight gradually and talk to their doctor or nurse about how to gain weight safely.

How much weight should I gain during pregnancy?

How much weight you should gain during pregnancy depends on your body mass index (BMI) before getting pregnant.

If you have:

Talk to your doctor, nurse, or midwife about how much weight is safe to gain during pregnancy.

What are the health risks for the mother of having overweight or obesity during pregnancy?

Having overweight or obesity during pregnancy raises your risk for problems during pregnancy. Also, even if you do not have overweight or obesity, gaining more weight than recommended can cause the same problems.

These include:

Talk to your doctor, nurse, or midwife about healthy weight gain during pregnancy to help lower your risk for these health problems.

Learn more about pregnancy complications.

How does having overweight or obesity during pregnancy affect the baby?

Babies born to mothers with overweight or obesity are at higher risk for health problems, including:

How does being underweight during pregnancy affect the baby?

Babies born to mothers who are underweight (women with BMIs lower than 18.5) are at higher risk for health problems, including:

Did we answer your question about weight, fertility, and pregnancy?

For more information about weight, fertility, and pregnancy, call the OWH Helpline at 1-800-994-9662 or check out the following resources from other organizations:

Weight loss and women

Women exercising on a treadmill

What is the best way for women to lose weight? Every woman is different, but recent research suggests that women may lose weight differently than men.

What is the best way for me to lose weight?

Most women will need to eat and drink fewer calories and get the right amount of healthy foods to lose weight. Increasing exercise or physical activity may help with weight loss, but choosing healthy foods (lean protein, whole grains, vegetables, and fruits) is what works best for many people to achieve a healthy weight.1 Combining healthy eating with increased physical activity is best. Talk to your doctor or nurse before starting any weight-loss program. He or she can work with you to find the best way for you to lose weight.

Your environment and other parts of your life may make weight loss more difficult. You may be able to take other steps, such as talking to your doctor about any medicines you take that may lead to weight gain, getting more sleep, or dealing with stress, that can also help you lose weight.

How many calories should I eat and drink to lose weight safely?

Everyone is different. How quickly you burn calories when you are not physically active can be very different from other people based on your specific genes, biology, and past. While scientists know that there are 3,500 calories in one pound, simply eating 500 fewer calories every day for a week (or 3,500 fewer calories in a week) does not always end in losing exactly one pound.

If you have overweight or obesity, counting calories may help you lose weight. Weight loss also happens when you focus on eating healthy foods. Getting calories mostly from lean protein, whole grains, and fruits and vegetables may help you lose weight safely.

No diet for an adult woman should be less than 800 calories per day. If you decide to limit the amount of calories you get each day to lose weight, talk to your doctor or nurse first. Your doctor or nurse can help you figure out a healthy and safe amount of calories for your body while trying to lose weight.

The exact calorie number to aim for depends on your age, your height and weight, and how active you are. Find out how many calories you need with the MyPlate Checklist Calculator.

Do women lose weight differently than men?

Yes and no. Men often lose weight more quickly than women. But, over time, weight loss usually evens out between women and men.

Men may lose weight more quickly because men usually have more muscle, while women may have more fat. Because muscle burns more calories than fat, men may be able to burn more calories at rest than women.

Because men are larger than women on average and have more muscle to support, men can usually eat more calories while still losing weight, compared to women. Portion control may be especially important for women. In one study, women who ate smaller portions of food (and less food overall) had lower BMIs than women who limited or avoided a certain type of food. This approach seems to work better for women than men.

How does the menstrual cycle affect weight loss?

The menstrual cycle itself doesn’t seem to affect weight gain or loss. But having a period may affect your weight in other ways. Many women get premenstrual syndrome (PMS). PMS can cause you to crave and eat more sweet or salty foods than normal. Those extra calories can lead to weight gain. And salt makes the body hold on to more water, which raises body weight (but not fat).

Also, while your menstrual cycle may not affect weight gain or loss, losing or gaining weight can affect your menstrual cycle. Women who lose too much weight or lose weight too quickly may stop having a period, or have irregular periods. Women who have obesity may also have irregular periods. A regular period is a sign of good health. Reaching a healthy weight can help women who have irregular periods to have cycles that are more regular. Learn more in our Menstrual Cycle section.

How does menopause affect weight loss?

It can be harder to lose weight after menopause. In fact, many women gain an average of 5 pounds after menopause. Lower estrogen levels may play a role in weight gain after menopause. But weight gain may be caused by your metabolism slowing down as you age, less-healthful eating habits, and being less active. You also lose muscle mass as you age, so you use fewer calories.

Staying active and eating healthy foods can help you stay on track with your weight-loss goals.

How can I avoid gaining weight as I get older?

Women usually need fewer calories than men, especially as they age. That's because women naturally have less muscle, more body fat, and are usually smaller than men. On average, adult women need between 1,600 and 2,400 calories a day. As you age, you need to take in fewer calories to maintain the same weight. You can also keep your weight healthy by increasing how much physical activity you get.

Find out how many calories you need based on your age and level of activity. You can also talk to your doctor or nurse about ways to eat healthy and get enough physical activity.

Will weight-loss medicines help me lose weight?

Maybe. Your doctor or nurse may recommend weight-loss medicine if:

OR

AND

The Food and Drug Administration approved several weight-loss medicines for the treatment of obesity. Most are not recommended for women who could get pregnant, because the medicines could cause serious birth defects in a baby.

Can over-the-counter or herbal weight-loss drugs help me lose weight?

Maybe, but you should always talk to your doctor or nurse before taking any herbal or dietary supplement. Find the main ingredient in your supplement on this fact sheet to see if it is safe and works.

There is no guarantee that “herbal” or “natural” weight-loss products are safe for everyone. The Food and Drug Administration does not regulate supplements in the same way it regulates medicines. Supplements often have side effects and can interfere with medicine you are taking. Learn more about dietary supplements.

What surgical options are used to treat obesity?

Weight-loss surgeries — also called bariatric surgeries — can help treat obesity. A doctor may suggest surgical treatment for weight loss if you:

Bariatric surgery is not a “quick fix.” It is major surgery. Learn more about weight-loss surgery.

Is liposuction a treatment for obesity?

Liposuction is not a treatment for obesity. In this surgery, fat is removed from under the skin. Liposuction can be used to reshape parts of your body. But if you gain weight following the surgery, fat may return to the places where you had surgery or develop in other places. Learn more about liposuction.

I carry extra weight, but I’m fit. Do I still need to lose weight?

It’s great that you are active and taking steps to improve your health! Sometimes your body mass index (BMI) may show that you are overweight even though you are fit. And some people may argue that how physically active you are is more important than how much extra weight you are carrying.

But this is only partly true. Being physically active can reduce your heart disease risk even if you do not lose weight. But your risk may be higher than that of someone who exercises and has a healthy weight. In other words, being active does not cancel out the dangers of having overweight.

Talk to your doctor or nurse to find out what a healthy weight is for you.

How fast should I try to lose weight?

It can be tempting to follow a “crash” diet and drop many pounds right away. But women who lose weight gradually are more likely to keep it off. Talk to your doctor or nurse about your goals. Your doctor or nurse can help you develop a healthy eating and physical activity plan.

I’ve lost weight but have hit a plateau. How do I continue losing weight?

After losing weight for about six months at the rate of up to 1 pound per week, most people hit a plateau, or a weight that doesn’t continue to go down. Once you lose weight, your resting metabolism (how many calories you burn at rest) goes down. At a lower weight, your body needs fewer calories to sustain itself.

Many people can lose about 10% of their original body weight in about six months. If you want to continue losing weight, you may need to adjust the amount of calories you eat and drink every day and your level of physical activity.

However, if you are eating healthy foods and getting regular physical activity but are still struggling with weight, you may want to talk to a doctor who specializes in obesity or weight management (link is external). It can also be challenging to keep off weight that you have lost.

Did we answer your question about weight loss?

For more information about weight loss, call the OWH Helpline at 1-800-994-9662 or check out the following resources from other organizations:

Tips for successful weight loss

Woman enjoying a healthy meal

Losing weight is difficult. Many women struggle to lose a few pounds and then put the weight back on again. There is no quick fix for losing weight. The key is to focus on small, healthy changes that you can stick with for the rest of your life. Losing weight is part of living a healthier lifestyle. Try some of these tips to help give you the best chance of success.

Make a plan for success

Get started

Eat healthy

Get moving

Get mentally healthy

Don’t give up!

Healthy weight resources

Woman conversing with a doctor

Learn more about healthy weight from the Office on Women's Health and other websites.

Learn more about healthy weight loss from the Office on Women’s Health

Top Questions About Healthy Weight and Women (PDF, 154 KB)

The Office on Women's Health is grateful for the medical review in 2018 by:

Page last updated: March 02, 2018.

Source: Office on Women’s Health, HHS