7 Ways To Measure Your Body Fat
1- Visual Perception
You can roughly estimate your body fat percentage simply by looking at yourself in the mirror, and comparing your body to a list of pictures that indicate the percentage of body fat. Here are some images that show how male and female bodies look like with different amounts of body fat.
Note: not everybody look alike if they have the same percentage of body fat, and this depends much on muscle mass. Here are two examples bellow.
2- Skinfold Measurements
They are measurements of folds of skin and the subcutaneous fat layer underneath it. You take these measurements from several locations of your body using skin fold calipers, and then enter them into an equation to predict the body fat percentage.
How It’s Done
- If you’re a male, you should measure in three places: the first is your chest (half way between the nipple and the crease of the armpit), the second is your abdomen (to the right or the left of your navel), and the third is your thigh. If you’re a female, the measuring spots would be the triceps, the suprailiac and the thigh. There are more body sites, but these are the most popular.
- Pinch the skin with your thumb and forefinger and pull it away to make sure that you’re not pinching the muscle underneath it.
- Use the caliper to measure the width of the skinfold
- It’s preferable that you take every measurement three times and take the average of them.
- Take the average of all the measurements and find your body fat percentage in the charts below.
- The calipers don’t cost much. Digital calipers are more expensive than other sorts, but still not too much expensive.
- You can do it without sophisticated equipment.
- The device used “the calipers” are portable.
- It’s a fast method.
- It’s not necessarily true that the fat under the skin has fixed proportions to the total body fat.
- If you have excess body fat the results may not be accurate.
- Errors in readings can be due to several factors, such as the amount of tissue picked up in the skinfold, and how hard you pinch it.
3- Bioelectrical Impedance
This method depends on measuring the resistance of body tissues to the flow of a tiny, harmless electrical signal.
- Electrical current faces less impedance when it flows through body parts that contain much water such as blood and muscle than it does through bone or fat.
- This method measures the speed and strength of the electrical signal that is sent through the body. Then depending on this measurement along with other information like weight, height, and gender it predicts the percentage of fat in the body.
- For home use: body fat scales use this method. Two built in footpad electrodes send a small current through your body from one leg to the other when you step on the scale. Now there are available handheld devices that use the same principle.
- Professional use: Spot electrodes are placed on your hands and feet. These electrodes are connected to a bioelectrical impedance device. There is also a professional model that uses foot pad electrodes.
- You need to be properly hydrated, because the settings of this method are based on normal ranges of water inside the body. So if you’re dehydrated, the percentage of fat will likely be overestimated.
- It’s better that you use it under the same conditions every time (adequate hydration and at the same time of the day) to get the best results.
- It’s a safe method.
- Some Bioelectrical Impedance systems (specially body fat scales) are fast and simple to use.
- Since you can use it at home, you can measure long term changes in your body fat.
- If you’re lean and athletic, this method tends to over predict your body fat, unless the device is equipped with an “athlete” mode.
- relatively inaccurate specially with body fat scales, and especially if the product is of low quality.
- It doesn’t show where the body fat is located.
- People with pacemakers shouldn’t use this method.
4- Near-infrared interactance (NIR)
In this method a fiber optic probe sends out a beam of near infrared light to an area of your body (usually the biceps). Some of this light gets absorbed, some of it gets transmitted, and some of it gets reflected. A detector within the probe measures the intensity of the light that penetrated the tissues then reflected off the bone. This probe is connected to a digital analyzer, which uses the readings of the detector along with age and activity level to calculate the body fat percentage using a prediction equation. This method depends on the fact that the ratios between tissues under the skin affect the intensity of the reflected near-infrared light.
- It’s a safe method and the device is portable and lightweight.
- Doesn’t require much training to be used.
- May not give accurate readings if there were thick fat layers.
- It assumes that fat in the biceps has fixed proportions to total body fat, which may not be true.
5- Underwater weighing
This method depends on the fact that fat has less density than other body tissues, which means that if you have more fat than someone who is exactly the same weight as you (in the air), your weight under water will be less than his. The body fat percentage is calculated after weighing the person in the air then weighing him under water, using a particular equation.
How it’s done
- You sit on a special scale in the water while just your head is above water, then you submerge your head completely in water and exhale as much air as you can.
- You remain motionless while your weight is recorded (it just takes a second or a few seconds).
- This procedure is repeated several times to get an accurate dependable reading.
- The operator enters the readings into an equation to calculate body density then body fat percentage.
- It was considered the accepted reference method of body fat estimation for many years.
- Some people feel uncomfortable when they are fully submerged in water, which may cause incorrect readings.
- An experienced operator is required for this procedure.
- It doesn’t show the distribution of fat in the body.
6- The Bod Pod
This method depends on measuring the size of the body, and it uses air to do that. Let’s take an example: if you and someone else have exactly the same weight but you have more fat than him, the volume of your body will be bigger than his, since fat is less dense than lean body mass.
How it works
Measuring the volume of the body with the Bod Pod depends on the relationship between the volume of air and its pressure. When you enter the Bod Pod the volume of air inside it lessens by an equivalent volume of your body, the device measures the difference in air pressure which enables it to measure your body volume.
How it’s done
- The operator takes basic descriptive data about you, such as your age and height, and then s/he enters the data into the machine.
- You wear minimal tight fitting clothing in order to not affect the readings
- You step on a scale with your minimal clothing to let the operator get your body mass
- You enter the Bod Pod chamber and sit calmly there, then the operator closes the door
- the door remains closed for about 20 seconds, the operator opens the door then closes it again for another 20 seconds to take a second measurement, then the results come out.
- It’s reasonably accurate
- The procedure is easy and doesn’t cause much discomfort.
- It’s a laboratory method, so the device couldn’t be carried around.
- It doesn’t show how fat is distributed in the body.
7- DEXA scan (Dual X-Ray Absorptiometry)
The DEXA scan calculates your body composition by passing a very low level X-ray of two deferent wave lengths through you towards the detector which is under the table that you lay on. How much of that x-ray of each wave length gets through to the detector in each pixel of you is determined by the overall density of your body in that pixel. The result of this scan divides the body into three components: bones, lean (fat free) mass, and fat mass.
- A precise and accurate method.
- Safe to use.
- Not only it gives the percentage of the body fat, it shows how fat is distributed in the body.
- The equipment used is expensive.
- Should be used in laboratory settings.