All About Body Fat, Test types and Accuracy

The body can be separated into two distinct parts, Lean Mass (muscle, bones, organs) and Fat Mass (body fat).

While some fat is healthy, a higher than average Fat Mass is associated with an elevated health risk. Fat that accumulates on the mid-section of the body (Android fat; also known as the “Apple Build”) further elevates your overall health risk.

Body Fat Test Accuracy,  listed most accurate to least accurate

  1. Dual X-Ray Absorption; Error rate of (±)1.8%
  2. Hydo-Static Weight; Error rate of (±) 2.5%
  3. Air Displacement; Error rate of (±) 2.2 to 3.7%
  4. Waist Circumference; Error rate of (±) 2.5 to 4%
  5. Skin-fold Calipers; Error rate (±) 3.5%
  6. Bio-Electrical Impedance; Error rate (±) 3 to 5%
  7. Near Infrared; Error rate of (±) 5%
  8. Body Mass Index; Error Rate of (±) 5%

Quick and Easy Body Composition Tests

These tests can be done quickly at home; however, they often don’t give you an exact body fat measure. They commonly cluster your results into risk categories. Click here to test now.

Body Mass Index: The most common way to figure percent body fat and overall health risk is to use the Body Mass Index (BMI), most frequently used by doctors and clinicians. The BMI is figured by a calculation based on your height and weight, or through using a BMI chart. This Method of estimating body fat is good for the average population; however, BMI can be very inaccurate, especially if you can answer “Yes” to the following questions:

  • Do you regularly participate in resistance training either occupational (work hardening) or recreational (weight training)?
  • Have you maintained a relatively stable weight in adulthood (not gaining weight like the average American population)?

If you answered “Yes” to both questions you’ll want to measure your Percent Body Fat using another method since BMI will assume that your extra body weight is from extra Body Fat, while your weight might be higher due to extra Lean Mass which is healthy?

On the Flip-Side; BMI can assume a person has too much lean mass if they have a condition that results in excess fluid retention. The error rate for using BMI to calculate percent body fat is (±) 5% which is quite large.

Waist Circumference: A simple at home health test is to measure your waist girth with a flexible but inelastic tape measure. This measure will allow you to see if you have too much belly fat. Standing, wrap the tape measure around your waist at the level of the hip bones. The hip bones can be felt by pressing gently in-and-down on the soft part of your side just under your rib cage. Your hands should come to rest on the top crest of the hip bones (usually at the level of the belly button).  Measure around the body with the tape measure level to the floor. Read the tape measure with the abdomen relaxed after fully exhaling. To be in the recommended lowest risk category;

  • Men should be under 40-inch waist
  • Women should be under 35-inch waist

The Simple Words of Dr Oz; “If your waist size is more than half your height – measured across your belly button – You have too much belly fat.” The error rate for using circumference measures to calculate percent body fat is (±) 2.5% to 4%.

Specialty Body Composition Tests (Assistance Required)

Skin-Fold Calipers; Low Cost, Quick and Easy, Requires a skilled test technician with at least 100 previous test experience to be most accurate, Error rate of (±) 3.5%,

Bio-Electrical Impedance; Hand held device, scale, or both hand & foot contacts for improved accuracy, Cost for unit is usually $100 or up, provides the ability to self test, Error rate of (±) 3% to 5%

Advanced Body Composition Tests

Require special facilities, additional cost, and require a skilled test Technician;

  • Dual X-Ray Absorption; Error rate of (±) 1.8%
  • Hydo-Static Weight; Error rate of (±) 2.5%
  • Air Displacement; Error rate of (±) 2.2 to 3.7%
  • Near Infrared; Error rate of (±) 5%
  • MRI to determine percent body fat is currently being developed