In this article, you will see various ways on how to measure body fat.
What is body fat and its relation to overweight and obesity?
Body fat is not your enemy and you should not be getting negative vibes about it. Our bodies need body fat to live and function well. In fact, body fat is what the body uses for reserve energy, insulation, and protection.
From the food we eat, the body stores fat. However, when too much body fat accumulates, it can lead to overweight and obesity plus all related diseases like type 2 diabetes and heart disease.
This sums into the conclusion that body fat is healthy unless it gets excessive.
Measuring body fat is quite not easy since people of the same weight can have different body fat percentages. Weight alone cannot tell how much weight or muscle you have.
The various methods used to measure body fat include the use of; body circumference measurements, skinfold calipers, bioelectrical Impedance Analysis (BIA), hydrostatic weighing and others as seen in this article.
Measuring the body fat percentage can tell how much of your body weight is fat. The lower the body fat percentage, the higher the percentage of lean muscle mass you have on you and vice versa.
Is BMI the same as body fat percentage?
Let’s break it down,
Body mass index
Body mass index or simply BMI, in short, is a measure of bodyfat basing on height and weight in application to adult men and women. With BMI, your height and weight are what you use to work out if your weight is healthy or not
The BMI calculator is normally used on adults 20 years and older. BMI correlates with total body fat which means that as the BMI score increases, so does the total body fat.
Body fat percentage.
With body fat percentage, you measure body fat using tools and instead of using height and weight. The waist, wrist, hip, and forearm circumferences are what we use in the measurement.
BMI is a lot more different from body fat percentage. Although they may all be aimed at finding and estimating body fat, their measurements are quite different.
What’s a good BMI?
We can calculate BMI using a mathematical formula. The formula is BMI= weight(kilogram) divide by height (meters squared).
A healthy or good BMI score is one that ranges between 18.5 and 24.9. This indicates that a person within this weight range has normal weight corresponding to his or her height.
A BMI chart is what we use to categorize people into underweight, normal, overweight or obese.
A good BMI ranges between 18.5 and 24.9i s normal and healthy, below 18.5 is underweight, 25.0-29.9 is overweight and beyond 30.0 is obese.
Body Mass Index
18.5 – 24.9
|25.0 – 29.9||
Various methods of measuring body fat percentage.
BMI has a direct way of calculating and finding the results. Unlike BMI, there are various ways of calculating body fat percentage.
In this article, we are looking at how to measure body fat using body fat percentage.
Body circumference measurements.
Using the shape of the body, you can estimate body fat percentage by measuring circumferences of various body parts.
It is a quick and easy method of fat estimation. In men circumferences of the neck and waist are measured. In women, addition to neck and waist, the hip circumferences are included too.
A man with a waist circumference of more than 40 inches has a higher risk of developing obesity-related conditions the same applies to a non-pregnant woman with a waist circumference of more than 35 inches.
The accuracy of body circumferences measurements can vary widely based on the similarity to the people used to develop the computing equations.
The equations may not be accurate for all people due to the differences in body shape and fat distribution. An error rate can be as low as 2.5-4.5% body fat but it can be higher.
2. Skinfold calipers.
Skinfold calipers are used to measure the thickness of subcutaneous fat which is fat under the skin at certain body locations.
You can take measurements 3 or 7 different locations on the body. In men and women, these body locations vary accordingly.
For women, the triceps area, above the hip bone, the thigh, and abdomen are used for the 3 – site measurement. For the 7-site measurement, the chest, near the armpit, and beneath the shoulder blade areas are also included.
In men, the 3 sites may be the chest, abdomen, and thigh, or one can use the chest, triceps, and the area beneath the scapula. Ares near the armpit and beneath the shoulder blade are included on a 7-site measurement.
The calipers are affordable and measurements can be taken quickly. You can get these calipers from amazon here.
However, the skill of the person performing the measurements can vary the results. Measurement errors can range from 3.5-5% of the body mass.
It may not be the friendliest body fat measuring method because it involves pinching the body.
3. Bioelectrical Impedance Analysis (BIA)
With the BIA method, the device used detects how your body responds to small electrical currents.
Electrodes are placed in the skin and of which some electrodes send currents into your body whereas others receive the signals after they have traveled through the body tissues.
It bases on the fact that electrical currents move through muscle easier than through fat due to its high-water content of muscle.
The BIA device then automatically computes your body’s body fat percentage using these signals.
BIA is quick and devices are easy to buy. However, devices that are publicly available are less accurate relating to those found in medical and research facilities.
The accuracy while using BIA varies with an error rate that ranges from 3.8-5% depending on the device used. Also, the accuracy varies depending on the food and fluid intake too.
You can check out some of these from amazon by clicking here.
4. Dual-Energy X-ray Absorptiometry (DXA).
The DXA uses the X-rays of two different energies to estimate the body fat percentage.
DXA scan is performed by lying on the back for approximately 10 minutes while x-ray scans all over the body.
The amount of radiation is low about the same amount you receive during three hours of normal living.
It is one of the methods that provide accurate and detailed information with a breakdown of different body regions. It also has a low error rate ranging from 2.5-3.5% fat.
However, DXA is unavailable to the general public only found in research and medical facilities. It is also quite expensive.
5. Multi-Compartment Models.
They are considered the most accurate method of body fat assessment and estimation. The models require multiple tests to get an estimation of body mass, body volume, body water, and bone content.
For example, hydrostatic weighing can provide body volume, BIS provides body water and DXA measures bone content. It is the most accurate method available with an error rate of less than 1% body fat.
It is however not available to the general public and only found in research and medical facilities.
6. Hydrostatic weighing.
Also known as underwater weighing or hydro densitometry estimates the body composition basing on its density.
You are weighed while submerged in water after exhaling as much air as possible from your lungs. You are also weighed while on dry land and the amount of air left in your lungs after exhaling is measured or estimated.
This information is then entered in equations to determine the density of your body which is then used to predict your body fat percentage.
It is accurate and relatively quick though available in universities, medical and research facilities. The Inaccuracy while using hydrostatic weighing can be as low as 2%.
The disadvantage of hydrostatic weighing is the difficulty for some individuals to be fully submerged in water. One needs to breathe out as much air as possible then holding the breath underwater, it can be a difficult process to master.
7. Bioimpedance spectroscopy (BIS)
BSI is quite similar to BIA as they both use the body’s response to small electrical currents. The devices also look similar but different technologies are used.
BIS uses a much large number of electrical currents than in BIA.
It is a quick and easy method through its typically only available at universities, research, and medical facilities. BIS is more accurate than BIA devices but has an error rate of around 3-5% fat.
8. Electrical Impedance Myograph (EIM)
EIM also uses the body’s response to electrical currents. Unlike BIA and BIS, EIM sends currents through smaller regions of the body.
The device is placed on different body parts to estimate body fat around those specific areas. This technology is been made to the public through inexpensive devices.
EIM is quick, easy, and is available to the general public. One of the studies reports a 2.5-3% error in body fat.
9. 3-D Body Scanners.
3D scanners use infrared sensors and then generate a 3D model of the body. The scanner’s equations estimate your body fat percentage based on the body shape. The 3D scanners provide more detailed information.
They are relatively quick, easy, and are available to the public though they aren’t affordable and simple like circumference measurement methods.
3D scanners are fairly accurate with errors less than 4% body fat. They are however not common and affordable.
Similar to hydrostatic weighing, ADP estimates the body fat percentage basing on the body’s density. Unlike hydrostatic weighing, ADP uses air instead of water. The relationship between the volume and air pressure allows the device to estimate the density of the body.
During ADP, you sit in an egg-shaped chamber while the pressure of the air inside is altered.
The method is advantageous as it is accurate and relatively quick and doesn’t need you to be submerged in water. ADP is only available in research and medical facilities. It is quite accurate with an error rate of 2-4% body fat.
Which is the most accurate test to measure body fat?
The Multi-Compartment Models method of measuring body fat is the most accurate with a 1% error rate of body fat.
Since it requires multiple tests on the body mass, body volume, body water, and bone content the information obtained give accurate estimates accordingly.
How can I check my body fat percentage at home?
At home, you can use the methods discussed below which are already discussed in this article.
- Skinfold calipers.
- Body Circumference Measurements
- Bioelectrical Impedance Analysis (BIA)
- Bioimpedance Spectroscopy (BIS)
- Electrical Impedance Myograph (EIM)
- 3-D Body Scanners
Smaller units of devices that measure body fat percentage are available for the public but the lack of proper experience may increase the chances of getting wrong body fat estimation.
Also, the devices being sold online are not as much accurate as measurements performed in medical facilities with experienced medical personals.
The bottom line.
Methods like skinfold, circumference measurements, and portable BIA devices are quite cheaper and can easily measure body fat percentage at home.
The methods with the highest accuracy will not be available at your home but rather in medical or research facilities with experienced handlers.
However, tests taken in medical facilities are expensive though. Now that you have learned how to measure body fat percentage, check out the articles below.
Here are articles that I wrote which you can refer to in order to burn that extra fat.
Subscribe for weekly insights on faster weight loss and good health.