Top 3 Most Accurate Methods For Measuring Body Fat

There are numerous methods to measure body fat. Having said that, there are also numerous ways to get inaccurate readings.  Most people go by their bathroom scale, or even a small hand-held device to find out how much fat they have.  The downfall to these methods are they do not offer accuracy, including the traditional skin-fold caliper measurements.  Typically these advisories claim to only have a 1-2% marginal error, for instance, including these 3 but they are far from 1-2%.



Measuring your body fat also comes with measuring your VO2 (oxygen levels), RMR (resting metabolic rate), as well as internal fat. Pinching is not going to give you what is stored in your liver or other organs (which sometimes are in much greater quantities that what lies beneath the skin).  In addition, it highly depends on how loose the skin is for the measuring individual to be able to pull the fat away without hurting you.  On the other hand, some people find it very uncomfortable having someone “pinching their fat” and would rather not know for the sake of embarrassment.  When it comes to other devices such as both bathroom scales and hand-helds, they do not have the scientific capability to generate accurate figures, although they are great for using as a “guideline.”  Undergoing either a Dexascan, Hydrostatic Weigh-In and/or a BodPod are your best bet for the closest calculations (or 1-2%) in obtaining your true body fat percentage.


Bod Pod

It’s common that many are not familiar with these methods which are understandable.  It’s not like they are readily available anywhere you go or something you can purchase for your own personal use.  But to help you out a little better, a brief description of each should help you decide which method you may prefer to have conducted.  A BodPod is a large egg-type structure you sit inside after the technician weighs you while the surrounding air calculates your density and/or fat-free mass which is defined as: bones, organs, water, blood, muscles, basically anything that is not body fat/adipose tissue.  Furthermore, you wear a “swimmers” cap so that any loose hairs do not disturb the airflow while wearing either a swimsuit or spandex so that there’s no additional air measured inside loose-fitted clothing.  This process in done three times over a period of about ten minutes of sitting very still and breathing normally that is painless, although can be uncomfortable for those who are claustrophobic.



Hydrostatic Weighing

A Hydrostatic exam is a more complex process as it physically involves more than just stepping on a scale or quietly sitting still.  This ordeal includes the measuring of your metabolic breathing which is the air density in your lungs as you inhale/exhale through a tube.  (Keep in mind that certain facilities may do this portion of the procedure a little differently, this is just a description of each step how it was performed on me).  Following this step is when you are harnessed with various straps attached to a scale and then are submerged under water holding yourself similar to “fetal position” or tight, like in a ball.  The technician will typically give you a few “practice rounds” at first so that you get the idea of how to exhale releasing all the air out of your lungs that could be measured as fat.  Obviously, this is not easy task.




To do this, there are two ways:  You can completely exhale as much as possible and THEN submerge yourself while letting your body sink.  OR, you can submerge yourself slowly yet steadily exhale underwater until your lungs are completely empty, (or to the point where there are no more bubbles) while letting yourself sink at the same time.  (I prefer the 2nd method.  Since I’m releasing the air or exhaling as I’m submerging, I’m sinking in the process which is steadier for me and less time with my lungs completely empty once I hit the base, or deepest point I’m capable of sinking to.  Basically, I’m buying myself some time at the bottom, about a couple of seconds which isn’t much, but it can make all the difference in the world when trying to get an accurate reading).


This method is NOT to be confused with just holding your breath underwater as many people can do that with ease and simply for the fact the procedure is still measuring the air density in your lungs which again, is buoyant, like adipose tissue.  Furthermore, holding your breath is still circulating around in your blood stream providing oxygen to the brain which keeps you fully aware and functioning.  Having NO air in your lungs can cut off that oxygen supply to your brain within around a minute and cause a black-out which could lead to other difficulties and/or damages.  This is why this process must be done in a timely matter and with an experienced technician, not to mention the reason for your “practice rounds.”  The object is that the further you sink, the less fat mass is measured.  The only “discomfort” some have other than the fear of having to go underwater is the feeling of briefly pushing their lungs to their limits while the technician gets a reading.


This is also done three times, all at the comfort of your own pace, to get an “average reading” from the scale you’re harnessed to which takes about 15-20 minutes in total, (depending on how many practice rounds you need).  These “average readings” are then calculated into various mathematical formulas to generate the most possible accurate figure/answer which is why there is a 1-2% marginal error (or overall estimate) which also goes for the BodPod procedure.


Both methods are suggested to briefly “fast” for approximately six hours so that any digestion doesn’t complicate the process.  For example, fibrous foods such as veggies, whole grains, beans, etc., even carbonated drinks can cause bloating/gas which calculates as fat.  In addition, having that extra weight of the food you recently consumed may not be much, but it will surely contribute to a greater marginal error to your overall results as it will off-set your true body weight.  Furthermore, something to consider, specifically to the ladies who have “refurbished the balcony” (aka breast augmentation) like myself; it may also add yet another small percentage of inaccuracies.  This is due to the slight difference in weight including what the substance is made of (i.e., silicone/saline).  You can contact your surgeon to get exact details to pass along to your technician to see if it’s at all possible to include into the calculations.


By now I’m guessing it’s safe to say it’s clear why you can’t just do these procedures anywhere or run out and buy them to store in your bathroom for personal use.  These equipment pieces can range from a small dining table to a pick-up truck (as far as referencing the water procedure/pool).  You can however, look up your local university and speak to someone in the science or health/wellness department.  Most of them offer this service to the general public but unfortunately, it’s not exactly cheap.  Expect to pay on average anywhere from $75-$125.  Some military bases offer the BodPod exam for free (or at most a fraction of the average cost) in their health-and-wellness centers for military personnel and their dependents only.   Since I am former military I was able to take advantage of this option although due to the current cut-backs to the DOD (department of defense, aka military), the Obama administration may have had the equipment removed because of the extra costs required in maintenance and (sometimes) civilian personnel operating it.


Many may agree that extra costs are hindering our economy.  On the flip-side, what we do need are healthy, strong soldiers that which various equipment is needed/suggested to ensure they are in tip-top shape, especially down-range so it’s kind of a catch-22.  I only made that statement just in case there are inquiries made on-base and end up disappointed to hear the outcome.  But since this topic is about measuring your body fat, I will steer back to that direction.  I personally find the Hydro option a better source than the BodPod considering the amount of steps and mathematics involved but both had very close results (a 2% difference in body fat taken within the same month and no change in my diet or exercise regimen).



As far as the Dexascan, it is today’s most accurate method or “golden standard” right down to the “T.”  It literally scans your body like an X-ray so that everything is measured and visible without the need to fast or be concerned about having implants.  Don’t worry; it’s not a machine that will make you appear “naked” like how many people overreact with silly assumptions regarding being X-rayed at an airport.  It’s not as wide-spread as the BodPod and Hydro testing, however, it’s expected to soon take over.  If this is a method that interests you most, you can call your physician to see if they know of any locations they can refer you to if they do not offer the services themselves.  Keep in mind some might also be at your local university and of course, you’ll have to pay out-of-pocket unless your doctor says so otherwise.  Overall, this procedure takes just a few minutes as well and although I have not researched the average cost, it would be wise to inquire if your insurance covers it.  In addition, I have not had this exam done personally as it would have been too far from my residency to participate.  As I mentioned, I have participated in the previous two discussed.




Given these procedures, steps, mathematics, fasting, surgical implants, etc. are all factors and reasons why your digital bathroom scales and hand-held devices are not a preferred method of measurement.  Again, they’re great to use as a good guideline to see if you are decreasing from whatever indicating numbers are shown.  A common scenario is for people to get measured via the skin-fold technique with a caliper/lange tool in which may result with a very low reading. Following that procedure they undergo one of these top three options and is likely their body fat reads higher.  Having said that, all of a sudden they assume something is wrong with the machine or equipment.  There’s nothing wrong, it simply means that the lange was only reading what is under the skin.  If anything, you will know the difference between your internal and external storage.  After all, body fat in general is essential.  Internal body fat is what protects our organs and stores a lot of the body’s vitamins and minerals for proper bodily functioning and regulation, whereas under the skin (or external) is typically more for body warmth.


With regards to “fancier” magnetic scales you stand on (typically in a doctor’s office), aka Bioelectrical Impedance Analysis (BIA), they read a little more accurate than the typical hand-held device.  Hand-helds are great for measuring your upper extremity while these higher-tech BIA’s are great for measuring your lower extremity.   This is because two of the four magnetic readers are bigger (where you stand) covering the area of your feet compared to the other two smaller magnetic readers where it just covers the area of your thumbs.  Although they collectively make one reading, you can see which extremity (upper/lower) is going to give a better feed-back due to the greater magnetic coverage.




The reasoning for the BIA having less accuracy is simple.  Water is a conductor of electricity so the more muscle you have, the stronger the current reaches the other side of the body (since muscle is composed of a lot of water).  These results will read a higher percentage of body fat if the testing individual is dehydrated whereas skin-folds will read lower because skin does not have as much elasticity so the calipers won’t grasp as much.  Again, pinching is ONLY capable of measuring what’s under the skin—IF it’s able to be properly measured.


If you can’t afford a BodPod, Hydro, or Dexascan, I would suggest the BIA next in line since they are cheaper.  This procedure can also be done on average for about $25-$45 and stronger in comparison to the hand-held.  Technicians will claim this type of equipment is very accurate, but considering all the various necessary factors previously mentioned as far as capabilities, plus once you do one of each, you will know very quickly with personal experience (like myself having done this procedure as well) that’s it’s not exactly true.  Regardless if you feel afraid or embarrassed learning what your body fat is, it’s always wise to get it done as it can give you an idea of where your current health is and where you want to take your fitness accomplishments.

Author: Heather Prescott was born in Los Angeles on May 18, 1978 where she grew up until age 30 when she joined the Air Force. She won ‘Most Physically Fit Female’ in Basic Military Training (BMT) and was also recognized as one of the most fit-females in her squadron at her assigned duty station. Her professional experience includes American Council on Exercise (ACE) certifications as both a Personal Trainer and Fitness Nutrition Specialist; is an all-natural, Nationally-Qualified Figure athlete with the NPC/OCB/NANBF/ABFF organizations with 11 competitions under her belt nation-wide consistently placing in the top 3. Heather has also written 2 books, “On-Season Off-Season;” a cookbook designed for individuals transitioning from poor eating habits to learning and understanding how to take clean-eating one-step at a time; each recipe 500 calories or less! Her second book, “Highway To Health,” is a book that breaks down the fitness industry’s most commonly misunderstood FAQ’s that discusses strength training, bodily function and regulation, clean-eating, nutrition, weight-loss, building muscle, even competition prep to name a few. To learn more about Heather, visit her website at: where you can also connect with her via social media!

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