The number is calculated using your weight and height. If you carry too much weight for your height, the excess weight is assumed to be fat. Body mass index is simply a tool that puts you into a category based on weight.

It is not designed to be an accurate diagnostic tool for determining health. Despite being a flawed measure , BMI is widely used today in the medical community because it is an inexpensive and quick method for analyzing potential health status and outcomes.

Why does body fat percentage matter? If your goal is weight loss , you might be tempted to use a simple bodyweight scale for feedback on your progress, but your body fat percentage will tell you more than the scale. When you are participating in intentional weight loss, boosting your health, or increasing your fitness level, fat loss should be your goal, rather than simple weight loss.

You want to keep the lean mass, or fat-free mass, that your body needs. Lean mass includes bone, blood, connective tissue, organs, and muscle.

Muscle loss sometimes occurs when you lose weight, but it's not the kind of weight loss you seek. You want to maintain muscle mass because it helps your body to function and perform more efficiently, boosts your metabolism, and can help improve glycemic control.

By measuring changes in body fat percentage, you can tell how well your fitness or weight loss program is helping you to lose fat while maintaining fat-free mass. There are many different ways to measure body composition or the amount of fat and lean mass on your body.

Using a body fat calculator is just one of them. One method won't be appropriate for every body. For example, if you would be uncomfortable going underwater, you would not want to attempt hydrostatic weighing.

Each method also has its pros and cons. When you input body measurements into a body fat calculator like the one above, the tool uses a specific formula to estimate your percentage of fat.

The formula is slightly different for men and women. For women, the formula begins with a simple weight calculation:. The tool uses fractions of each body measurement to estimate your body fat percentage. For men, the formula begins with a different weight calculation:. The tool uses a fraction of the weight measurement to estimate your body fat percentage.

A body fat calculator is not the most accurate measurement of body fat percentage. However, it's the most accessible system to use. Therefore, you may be able to use it more often. If you measure at the same time each day and use the same tools the same tape measure and the same online calculator , you can track trends in your progress, which can be far more valuable in assessing your fitness gains than a standalone measurement.

Several body fat calculators use skinfold measurements instead of body circumference measurements to estimate your body fat percentage.

Skinfold calipers can be purchased to use at home, or you can hire a professional who is skilled in using them in healthcare or gym settings. Skin calipers pinch a portion of your body to estimate fat levels. The caliper method can be more accurate than a calculator for measuring body fat percentage, but the accuracy depends on the skill level of the person using them.

Home scales, gym-quality scales, and devices in your healthcare provider's office may use bioelectrical impedance to estimate body fat.

Simply put, the device sends a harmless, completely pain-free electrical signal through your body to measure fat. You get a quick and instantaneous body fat percentage result. While this method is convenient, certain factors such as hydration level can influence the accuracy of the result.

Whole-body scanning is quickly becoming the gold standard for measuring body fat percentage. However, the main reason the test is so accurate is that it is generally performed in a medical setting by highly skilled technicians.

The DeXA test is often costly and may not be available where you live. This submersion method has long been recognized as the most accurate measurement of body fat percentage. However, it requires a person to be fully immersed in a tank of water while holding their breath.

For many, the endurance required for hydrostatic weighing can be a challenge. It can also be difficult to find a location that performs the test. Because thinness has so much value in many cultures, many people want to lose weight at some point. However, reducing body fat should not be a goal for everyone.

Speak with a healthcare professional before making a decision. It's also important to know that these numbers don't apply to pregnant people—you should not try to lose weight during pregnancy.

You'll also want to talk to a healthcare provider if you are trying to lose weight while on medications or during cancer treatment to ensure that it is safe. If your doctor determines that reducing your body fat percentage is a safe and beneficial health goal, here are some areas for you to consider making changes.

How much you eat and what you eat are significant factors in losing or gaining body fat. You might be tempted to try a popular diet, but fad diets generally don't work. What does work is making small changes, such as:.

Cardiovascular exercise is an important part of any fat loss program, but you want to ensure you do the right cardio. Make sure you include some high-intensity interval training in your program, up to two to three times per week. In addition to cardio, you should also incorporate moderate and easy workouts.

People often focus on cardio to lose weight, but adding more muscle will help you burn more fat. Muscle is more metabolically active than fat, so the more you have, the more calories you burn all day. Strength training a couple of times a week is all you need to add lean muscle tissue and burn more fat.

Watching your stress levels and getting enough sleep are the keys to keeping your weight in check since stress hormones can contribute to weight gain. Taking care of yourself will make it easier to maintain the energy needed to complete key workouts and help you stay motivated to shop for and prepare nutritious foods.

There are other methods of measuring body fat not listed here. Whichever way you choose, remember that if you plan to measure your body fat regularly, you need to use the same method each time to get the most accurate data. If you want to change your body fat composition, a balance of nutritious eating and being sure to avoid fad diets, coupled with exercise, is the best bet.

Consult a healthcare provider to assess your health risks and make a plan for staying healthy. American Council on Exercise. Percent body fat calculator: skinfold method. Macek P, Biskup M, Terek-Derszniak M, et al. Optimal body fat percentage cut-off values in predicting the obesity-related cardiovascular risk factors: a cross-sectional cohort study.

Diabetes Metab Syndr Obes. Al-Ozairi E, Alsaeed D, Alroudhan D, et al. Skeletal muscle and metabolic health: how do we increase muscle mass and function in people with type 2 diabetes?

J Clin Endocrinol Metab. Bryant CX, Green DJ, Newton-Merrill S. ACE Health Coach Manual: the Ultimate Guide to Wellness, Fitness, and Lifestyle Change. American Council on Exercise, Centers for Disease Control and Prevention. About adult BMI. Updated April 10, Some believe that WHR may be a better indicator of risk than waist circumference alone, as waist size can vary based on body frame size, but a large study found that waist circumference and WHR were equally effective at predicting risk of death from heart disease, cancer, or any cause.

The World Health Organization has also found that cut-off points that define health risks may vary by ethnicity. For example, Asians appear to show higher metabolic risk when carrying higher body fat at a lower BMI; therefore the cut-off value for a healthy WHR in Asian women is 0.

Stand up straight and follow the directions for measuring waist circumference. Then wrap the tape measure around the widest part of the buttocks. Divide the waist size by the hip size. The WHO defines abdominal obesity in men as a WHR more than 0.

Waist-to-height ratio WHtR is a simple, inexpensive screening tool that measures visceral abdominal fat. It has been supported by research to predict cardiometabolic risk factors such as hypertension, and early death, even when BMI falls within a healthy range.

To determine WHtR, divide waist circumference in inches by height in inches. A measurement of 0. Equations are used to predict body fat percentage based on these measurements. It is inexpensive and convenient, but accuracy depends on the skill and training of the measurer.

At least three measurements are needed from different body parts. The calipers have a limited range and therefore may not accurately measure persons with obesity or those whose skinfold thickness exceeds the width of the caliper.

BIA equipment sends a small, imperceptible, safe electric current through the body, measuring the resistance. The current faces more resistance passing through body fat than it does passing through lean body mass and water.

Equations are used to estimate body fat percentage and fat-free mass. Readings may also not be as accurate in individuals with a BMI of 35 or higher.

Individuals are weighed on dry land and then again while submerged in a water tank. This method is accurate but costly and typically only used in a research setting. It can cause discomfort as individuals must completely submerge under water including the head, and then exhale completely before obtaining the reading.

This method uses a similar principle to underwater weighing but can be done in the air instead of in water. It is expensive but accurate, quick, and comfortable for those who prefer not to be submerged in water.

Individuals drink isotope-labeled water and give body fluid samples. Researchers analyze these samples for isotope levels, which are then used to calculate total body water, fat-free body mass, and in turn, body fat mass.

X-ray beams pass through different body tissues at different rates. DEXA uses two low-level X-ray beams to develop estimates of fat-free mass, fat mass, and bone mineral density. It cannot distinguish between subcutaneous and visceral fat, cannot be used in persons sensitive to radiation e.

These two imaging techniques are now considered to be the most accurate methods for measuring tissue, organ, and whole-body fat mass as well as lean muscle mass and bone mass. However, CT and MRI scans are typically used only in research settings because the equipment is extremely expensive and cannot be moved.

CT scans cannot be used with pregnant women or children, due to exposure to ionizing radiation, and certain MRI and CT scanners may not be able to accommodate individuals with a BMI of 35 or higher. Some studies suggest that the connection between body mass index and premature death follows a U-shaped curve.

The problem is that most of these studies included smokers and individuals with early, but undetected, chronic and fatal diseases. Cigarette smokers as a group weigh less than nonsmokers, in part because smoking deadens the appetite.

Potentially deadly chronic diseases such as cancer, emphysema, kidney failure, and heart failure can cause weight loss even before they cause symptoms and have been diagnosed.

Instead, low weight is often the result of illnesses or habits that may be fatal. Many epidemiologic studies confirm that increasing weight is associated with increasing disease risk.

The American Cancer Society fielded two large long-term Cancer Prevention Studies that included more than one million adults who were followed for at least 12 years. Both studies showed a clear pattern of increasing mortality with increasing weight.

According to the current Dietary Guidelines for Americans a body mass index below But some people live long, healthy lives with a low body mass index. But if you start losing weight without trying, discuss with your doctor the reasons why this could be happening.

Learn more about maintaining a healthy weight. The contents of this website are for educational purposes and are not intended to offer personal medical advice. You should seek the advice of your physician or other qualified health provider with any questions you may have regarding a medical condition.

Never disregard professional medical advice or delay in seeking it because of something you have read on this website. The Nutrition Source does not recommend or endorse any products. Skip to content The Nutrition Source. The Nutrition Source Menu. Search for:.

Home Nutrition News What Should I Eat? Role of Body Fat We may not appreciate body fat, especially when it accumulates in specific areas like our bellies or thighs.

Types of Body Fat Fat tissue comes in white, brown, beige, and even pink. Types Brown fat — Infants carry the most brown fat, which keeps them warm. It is stimulated by cold temperatures to generate heat.

The amount of brown fat does not change with increased calorie intake, and those who have overweight or obesity tend to carry less brown fat than lean persons. White fat — These large round cells are the most abundant type and are designed for fat storage, accumulating in the belly, thighs, and hips.

They secrete more than 50 types of hormones, enzymes, and growth factors including leptin and adiponectin, which helps the liver and muscles respond better to insulin a blood sugar regulator.

But if there are excessive white cells, these hormones are disrupted and can cause the opposite effect of insulin resistance and chronic inflammation.

Beige fat — This type of white fat can be converted to perform similar traits as brown fat, such as being able to generate heat with exposure to cold temperatures or during exercise. Pink fat — This type of white fat is converted to pink during pregnancy and lactation, producing and secreting breast milk.

Essential fat — This type may be made up of brown, white, or beige fat and is vital for the body to function normally. It is found in most organs, muscles, and the central nervous system including the brain.

It helps to regulate hormones like estrogen, insulin, cortisol, and leptin; control body temperature; and assist in the absorption of vitamins and minerals. Very high amounts of subcutaneous fat can increase the risk of disease, though not as significantly as visceral fat.

Having a lot of visceral fat is linked with a higher risk of cardiovascular disease, diabetes, and certain cancers. It may secrete inflammatory chemicals called cytokines that promote insulin resistance.

How do I get rid of belly fat? Losing weight can help, though people tend to lose weight pretty uniformly throughout the body rather than in one place. However, a long-term commitment to following exercise guidelines along with eating balanced portion-controlled meals can help to reduce dangerous visceral fat.

Also effective is avoiding sugary beverages that are strongly associated with excessive weight gain in children and adults.

Bioelectric Impedance BIA BIA equipment sends a small, imperceptible, safe electric current through the body, measuring the resistance. Underwater Weighing Densitometry or Hydrostatic Weighing Individuals are weighed on dry land and then again while submerged in a water tank.

Air-Displacement Plethysmography This method uses a similar principle to underwater weighing but can be done in the air instead of in water.

Dilution Method Hydrometry Individuals drink isotope-labeled water and give body fluid samples. Dual Energy X-ray Absorptiometry DEXA X-ray beams pass through different body tissues at different rates.

Computerized Tomography CT and Magnetic Resonance Imaging MRI These two imaging techniques are now considered to be the most accurate methods for measuring tissue, organ, and whole-body fat mass as well as lean muscle mass and bone mass. Is it healthier to carry excess weight than being too thin?

References Centers for Disease Control and Prevention. Adult obesity facts. Guerreiro VA, Carvalho D, Freitas P. Obesity, Adipose Tissue, and Inflammation Answered in Questions. Journal of Obesity.

While some storage fat is ideal, excess amounts of storage fat can have serious negative health implications. Excess body fat leads to the condition of being overweight and eventually to obesity given that insufficient measures are taken to curb increasing body fat.

Note that being overweight does not necessarily indicate an excess of body fat. A person's body weight is comprised of multiple factors including but not limited to body fat, muscle, bone density, and water content.

Thus, highly muscular people are often classified as overweight. The rate at which body fat accumulates is different from person to person and is dependent on many factors including genetic factors as well as behavioral factors such as lack of exercise and excessive food intake.

Due to varying factors, it can be more difficult for certain people to reduce body fat stored in the abdominal region. However, managing diet and exercise has been shown to reduce stored fat. Note that both women and men store body fat differently and that this can change over time.

After the age of 40 or after menopause in some cases for women , reduced sexual hormones can lead to excess body fat around the stomach in men, or around the buttocks and thighs of women.

The World Health Organization WHO classifies obesity as one of the leading preventable causes of death worldwide that is estimated to claim , to , deaths per year in the U. This has been a growing cause for concern because adults are defined as obese according to the Centers for Disease Control and Prevention.

Obesity is associated with a reduction in quality of life, poorer mental health outcomes, obstructive sleep apnea, as well as multiple leading causes of death worldwide such as cardiovascular disease, stroke, certain cancers and diabetes. All of these potential complications have the ability to reduce a person's life expectancy, and as such, obesity is a medical condition that is studied by many researchers.

As previously mentioned, fat produces a number of essential hormones that affect a person's body. An excess or a lack of critical hormones can have negative effects that preclude proper body function.

On a related note, studies have found that excess body fat, particularly abdominal fat, disrupts the normal balance and function of some of these hormones. Furthermore, body fat, specifically visceral fat, has a role in the release of specific cytokines, which are a broad category of proteins involved in cell signaling, that can potentially increase the risk of cardiovascular disease.

Visceral fat is also directly associated with higher levels of low-density lipoprotein LDL cholesterol, lower high-density lipoprotein HDL cholesterol, and insulin resistance. LDL cholesterol is commonly referred to as "bad cholesterol" while HDL is referred to as "good cholesterol.

Insulin resistance involves cells not properly responding to the hormone insulin, which can lead to high blood sugar levels, and eventually to type 2 diabetes.

As can be seen, excess visceral fat can have measurable negative impacts to a person's health. There are many specific techniques used for measuring body fat.

The calculator above uses a method involving equations developed at the Naval Health Research Center by Hodgdon and Beckett in The method for measuring the relevant body parts as well as the specific equations used are provided below:. Once these measurements are obtained, use the following formulas to calculate an estimate of body fat.

Two equations are provided, one using the U. If you already know your body fat percentage and are confident of its accuracy, you can simply enter the value manually and then note your status in the charts provided. You can choose the BMI method where only your height and weight measurements are required.

For the U. Navy and Covert Bailey methods, you will require a flexible measuring tape to measure the circumferences of various areas of your body.

For the Jackson-Pollock and Durnin-Womersley methods, you will need a skinfold caliper to measure the skinfold thickness at several sites on your body. The BMI method calculates body fat percentage based on age, sex, height, and weight.

It is the least accurate of all the methods. It only gives a ballpark estimate for those who don't want to bother with measuring tapes or skinfold calipers.

Note also that it's only intended for individuals living a sedentary lifestyle. Circumference measurements, used in the U. Navy and Covert Bailey methods, offer an easy and reliable way to measure body fat.

Both methods require a flexible and nonstretchable measuring tape to measure the circumferences around specific body areas. All measurements are taken against the bare skin with tape measurements made parallel to the floor with the exact amount of tension at the same spot each time.

The tape must be snug against the skin but not enough to compress the underlying soft tissues. All measurements, including height and weight, should be made in thin underclothes and without shoes.

Measurements must be taken at the same time of day before any physical activity to provide a consistent estimate to chart your progress. The U. Navy developed an excellent formula using body circumference measurements to determine the fat content in a person's body.

This calculation considers all service members, as they must meet specific percent standards regarding body fat percentage. Neck, waist and hip circumference measurements are required for women. The hip measurement is not required for men. Waist measurements are taken at the belly button for men and just above the belly button for women.

You can click on the help? icon next to the input fields in the calculator to get specific details. The accuracy of the U. Navy Body Circumference method is around 3. The Covert Bailey Method is named after its creator, fitness expert Covert Bailey.

Bailey has been a leading voice in the fitness industry for over 30 years, and countless people worldwide have used Bailey's method of calculating body fat percentage.

It's considered one of the most recent formulas to measure body fat. According to Bailey, for most people, the tape-measure test's accuracy is within 2. Personal trainers commonly use skinfold measurements to estimate body fat in local gyms. Using skinfold calipers require some training and experience for maximal efficacy and can predict body fat percentages within plus or minus 3.

Generally, the more skinfold sites measured, the greater the accuracy. Refer to the skinfold caliper manual for instructions. As a general rule, always take skinfold measurements from the right side of the body.

Take a minimum of two measurements at each skinfold site. If the two measurements differ by more than 2 mm, take a 3rd. Record the average for the site. Click the help? icon next to the input fields for info on the exact location of the skinfold measurement.