Is BMI Accurate?

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bmi chartBody mass index (BMI) is used to determine whether you are at a healthy weight. It’s a very simple formula that uses just two variables – height and weight. Can you really get a good measurement of health from BMI?

Is BMI Accurate?

Let’s take a look at the BMI chart above. Look closely at the section highlighted in orange. If you fall into this section, you are considered overweight. Now, do you think that a 5’6″ male that is 181 pounds is overweight? I don’t, but according to this chart, that person wouldn’t just be considered overweight, but he would be nearly obese. You tell me, does this person look like he’s almost obese?

Does Kendrick Farris look overweight or even close to obese?

What about a 5’8″ female that is 158 pounds? According to the BMI chart – just 3 pounds away from being overweight. Does the person below look 3 pounds away from being overweight? Do you see the pattern? For people living an active and fit lifestyle, BMI is close to worthless.

Shannon Humphrey

Does Shannon look close to being overweight?

I’ve heard countless stories like this from other people too. Doctors telling their patients they need to lose weight because this arbitrary BMI chart says they’re overweight. When are we going to move beyond such a ridiculous measurement? The body mass index (BMI) was created during the 1800s. Have we not advanced enough as a society to figure out how meaningless this measurement really is?

Is BMI Accurate? NO. Then What Is?

Thankfully, there’s no need to reinvent the wheel. We already know how to take accurate body composition readings. Body fat measurements tell the bigger story. We even have tests now to show how much fat mass, muscle mass, and other mass our bodies are comprised of.

A simple body fat caliper test can measure your fat mass and non fat mass. It can’t quite measure lean body mass accurately (it groups all non fat mass together), but that’s OK. For a person that is concerned about being fit and healthy, a $10 pair of body fat calipers is all they need to accurately track their health and fat loss progress.

Here is a body fat caliper and tape measure combo for under $10 that you can use to measure body composition.

Let’s Put an End to Weight Measurements

Do you even know what your body fat percentage is? Odds are that you don’t. That’s OK. You know what you have to do. Everyone should know what their body fat percentage is. It’s a real eye opener. It’s an even bigger eye opener once you take your second body fat measurement after a month or so of healthy eating and exercising. It’s then that you start to realize the meaningless stat of weight and BMI, and you start to appreciate the importance of body composition.

Not only could you have lose more fat than the scale is showing, but you could have also put on some muscle. Can the BMI show you that? Not a chance. Is the BMI accurate? Only as an average of the population at whole. For people living a fit lifestyle, it’s time to retire the BMI for good.

Calculate your BMI from the chart. Is it accurate? Does it represent a good portrayal of your body composition?

MUST READ: The Definitive Guide for How to Lose Weight
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About Tony Schober

Healthy living curator, blogger, foodie, certified personal trainer, husband, & step-dad to 3. Founder of Coach Calorie. Hates scales.

  • Mary Clarke

    So glad you posted this article. I am currently on a weight loss journey having lost almost 70 pounds so far. When I first started, I looked at my BMI and was very discouraged. Several weeks later as I was getting into more specifics, i.e. fat mass versus lean mass, I figured out that BMI was bunk. What is most disturbing to me is that medical professionals so readily accept this as a measurement of health as a standard, which is mind blowing. Specifically the surgical weight loss practices use this as a measurement to determine if individuals qualify for weight loss surgery. I would venture to guess that the majority of health care professionals have no idea where the measurement comes from or when it was put into practice. As you said, in the 1800s. Furthermore, it was not created by a health care professional, but a mathmetician! I am so glad that you are educating people on this issue. I love your daily articles. They help me to stay focused on the task at hand and question whether I am on the right track.

    • Coach Calorie

      Unfortunately, it’s going to take some time before we readily move to body composition as a measurement of health. The chart is just too easy and quick to use to be replaced anytime soon. Slowly but surely…

      Glad you like the articles!

      • Julie Shaw

        Well done Mary on your weight loss, I too have lost 70lb through exercise and healthy eating, this has left me at 48 with an apron of skin that is hanging and saggy and makes me cry every time I look in the mirror. I know that no matter what i do or how much more weight i loose (and i still have a bit to go) this will not look any better. I have turned my life around and become a Personal Trainer, but this flabby tummy of mine is affecting my confidence, why should my clients listen to what i tell them while I have this bulging baggy belly.
        I went to the doctor to request he refer me for surgery to have it removed but my BMI was 31 and he said I have to get it below 30 to QUALIFY for referral. This has disheartened me with all the lifestyle changes I have made by myself with no help from the medical profession.
        I wonder what I would have to take it UP to so that i could qualify for Barriatric Surgery to help me get my BMI below 30 so I could qualify for a Tummy Tuck.
        Now that is a thought, I think i may pay my Doctor another visit and tell him this is what i am considering doing just so i can get rid of my loose skin………..watch this space.!!!!!!

        • Coach Calorie

          Julie, they’ll listen because loose skin or not, you obviously made the transformation and can teach others how to do it. Don’t get discouraged!

      • Sharon Sanders

        The BMI chart you posted is labeled wrong! BMI 18 or under is underweight, the green is the Healthy Weight, a BMI 25 or over is Overweight, and BMI of 30 or more is Obese. I agree that the BMI for men isn’t accurate if muscular, but for women the BMI gives a wide range for Healthy Weight, even if muscular. People should look more at body fat percentage and waist size. For women a waist over 35 is dangerous and for men over 40, plus it’s a sign of possible metabolic syndrome or diabetes. People with a large waist usually also have high triglycerides, low HDL and high BP, so they should be checked for diabetes.

        • Coach Calorie

          Hi Sharon, what you posted is what the chart says. Take a look at the “chart key” at the top. It’s a bit confusing because the label “underweight, healthy, overweight, etc” is above a different column, but it’s next to the correct color to the left that it’s labeling.

  • http://talktalk patricia davies

    im so glad you put that up im according to bmi index im overweight im 5ft and weigh 9st 4lbs im just a tidge over what i left school i couldnt be any thinner id be ill as id have to be anorexic to be the weight they said wait for it 7st 2 to 7st 9 never in a month of sundays no wonder girls are dieting the way they are im 49 years old i exercise everyday cos i love it and i eat really healthy so i told them to stick there bmi up where the sun dont shine trishxxx

    • Coach Calorie

      For some people to fit into a healthy “BMI”, they would actually need to lose muscle! While the whole “Fit is the new skinny” slogan is getting a little old, I’m glad the transition is taking place.

  • Karen Richardson

    Thank god finally someone with some sense. I am classed as on the line between obese and dangerous according to doctors the only thing is i am only a size 14. Yes i am over weight for my height but not massively. I do weight lifting aswell but they don’t take that in to account. I just need to lean out the fatty bits. Its the same with my son he got his first school health check at the age of 5 and I got a letter to say that hes over weight and needs to diet. OMG he is the tallest in his class infact he is the same height as the 8 year olds at his school and hes now way fat in the least so I tore up the letter as i feel all this BMI stuff is alot of rubbish and could possibly damage alot of people physically and mentally trying to keep doctors happy. “Eat healthy and excersice regularly and you wont have a problem with weight” thats what doctors should be saying.

    • Coach Calorie

      For people that exercise, BMI will always skew the readings to the right of the chart (more towards obese). It can be a useful guide for people who live a sedentary lifestyle, but for fitness minded people, body fat percentage is the better indicator.

  • Jennifer Jessel

    Do you know where I can buy a pair of at calipers?

    • Coach Calorie

      Jennifer, head over to Amazon.com and do a search for body fat calipers. You will find that they range from under $10 for a plastic pair to over $100 for a nice pair. One might end up being more reliable than the other, but it’s the relative change from measurement to measurement that’s equally important.

  • Traci B

    I have lost 75lbs over the past 3.5yrs. I was seriously overweight at 215lbs, 43% BF… I am now 5′ 6″ and 140lbs, 19% BF. Most of society would think that 140lbs is too heavy. It is sad that we live in a world that we are programmed to only concentrate on the numbers. I am leaner than I’ve ever been in my life, stronger than I could ever thought I could be… I wear a size 2/3 jeans, xs in athletic wear, etc…. Hopefully someday the medical field will open their minds and eyes to the fact that no two people weighing the same but with different body compositions will look the same. I am the same height and weight as my mother but she doesn’t workout like I do… she looks as if she was a good 15lbs heavier than I. Also she wears a size 8 vs my size 3. I definitely agree with the “fit is the new skinny” mentality. Fit is sexy. Congrats and Kudos to all that have traveled the fitness/weight-loss path. I too having had 4 kids and riding the weight gain/loss rollercoaster, sport a patch of skin on my belly that will not firm up for the life of me. I am also a PT. My clients are relieved I understand the struggles, misconceptions, joys, pains of weightloss.

    • Coach Calorie

      Congrats on your success Traci. Part of being a good trainer is being able to relate to other people.

  • Marina Coleman

    I was thinking of getting a pair of calipers… i presume it matters where you measure? Fore instance if i measure my thigh it will show less than my tummy? Like Julie i too have flabby belly after having 3 large babies but at 45yrs old now and running 4klm every 2nd day plus weight training i find only the tummy area disappointing(stretched and excess skin).

    • Coach Calorie

      There are 2 ways to use calipers.

      1 – to measure the relative change in skin-fold measurements from a particular site (ie thigh, butt, triceps, etc)
      2 – to measure your body fat percentage (you will have to measure at particular places for this)

      For #2, google “body fat skin-fold sites”, and there should be plenty of diagrams of where you should measure. Once you have those measurements, you can put them into a calculator and get your BF%

      • Marina Coleman

        Understood,many thnx and btw your site is amazing! Full of ideas and encouragements not to mention recipes and motivational inspirations.Keep it going mate! Cheers

  • Cindi Anderson

    I have always been considered overweight according to bmi charts. I’m 5’1 1/2″ and I have a muscular frame. Growing up I felt I was fat because that’s what I heard-although I wasn’t fat at all, not even overweight. I have always been an athletic person. Even now, at 43, having had a baby by C-section 6 months ago, I exercise regularly, play co-ed softball, and take advantage of outdoor activities. Granted, I do have some baby fat to lose, but when I calculated my BMI I was so discouraged to be in the obese range, and this was before I became pregnant with baby number 3! These charts never take into account a person’s muscle mass or body frame. Muscle weighs more than fat. I’ve had people tell me-who are considerably overweight-their weight and I outweigh them by 20 pounds or more. All my life I have felt extremely fat, even when I was at a healthy weight because the “chart” said I was. It’s great to read articles such as these. It would have been even better if I could have read something like this when I was a teenager because it might have helped with my low self-esteem with my body image that has stayed with me! Thank-you!!

    • Mary Clarke

      Well said Cindi A. I have had the same thoughts on my weight loss journey over the past year….I wish I had know this information as a teenager. But the blessing is that you DO know now and we can both help our children have positive body images as they grow up.

  • Karen Ruffle

    I am 5ft 4, weigh 143lbs & am UK dress size 8-10, my BMI is 24 just in healthy range however my total body fat is 14%. (January 2012 I was 200lb, UK 16-18 & body fat of 38%) Knowing my real fat% is low, I would happily take on any doctor who says I am borderline overweight based on the outdated BMI chart.

    • Coach Calorie

      Good job Karen. 14% body fat at your height and weight is very good!

  • http://www.missfitnesslife.com Vix- Miss Fitness Life

    Body Fat Percentage is a much better measure than anything else. Getting into shape is all about burning fat and maintaining or increasing muscle and only body fat % shows this.

    It can take some time to get the hang of callipers- the key is to practice and practice.

  • Rossana

    I agree the above chart can be quite out of whack…but in my case it’s spot on at the moment.
    I also think the waist to hip ratio method of measuring body fat can be wrong…I think it should be waist to height ratio…makes more sense to me. Oblong people are slimmer looking than square people..lol

  • http://www.alsfoodandfitness.com Alex

    YES! It’s not all about the numbers on the scales. I lift weights – how on earth am I going to get lighter when my body composition is leaning towards gaining muscle mass?

    I’ve lost 5lbs in the last few months, which is barely anything on the scales – but I’ve almost dropped an entire dress size in inches. That’s what’s more important to me and should be to more people.

  • Mike B

    What about the Hydrostatic Body Fat testing where they submerge you? Is this a reliable test?

    • Coach Calorie

      Hi Mike, yes it is accurate. That and the DEXA scan are very accurate methods to test body fat %

  • http://www.exercise-fitness-nutrition.com Sue Kauffman

    Our school district sends a letter home each year with each student. It lists height and weight of the student with a BMI chart listing which BMI’s are underweight, normal, overweight, obese etc. With the increase in disordered eating and poor body image in the teenage population, this could be devastating to certain students. Of course testing body fat for each student would take too long and would probably upset some parents and students, but it would certainly paint a more accurate picture.

  • Angie

    As a fitness professional I have always struggled with BMI. Working in a corporate setting where people are hesitant to have their BF taken, it remains the fall back tool. I dislike it so much that I work hard on building a relationship with the individuals so they feel comfortable enough and trust me to take their body fat. I am continually telling the story of a friend of mine who has completed TWO Ironman triathlons and according the BMI chart he is obese. That is ridiculous. I also hear a lot of people say – I am big boned. As a results I have found charts that indicate frame size based on wrist and elbow measurements. I hate to burst bubbles but if changes are to be bad, expectations must be realistic and people need to understand where they are really starting from. The journey is about healthy eating, exercise, hydration, being real with yourself, and having lots of patience. Thanks so much!

  • Jewels

    I have to say that you actually just helped my head

    For the past three years I was under a huge amount of emotional stress due to a now ex who assisted in my now hormonal imbalance, adrenal fatigue leading to hypothyroid which caused me to gain an excessive amount of weight due to all the stress and abuse I endured

    I have always been very healthy w/ great endurance;however, this past ordeal as well as age took a toll on me but once I stopped listening to others and went back to my own confidence my situation has changed in a positive way; however, the BMI chart (and to my point) has completely messed with my head.

    Now don’t get me wrong I have a lot of work to do to get back to where I feel my best but by no means do I look obese and according to the chart I am 2lbs away from being obese now it states I am overweight and yes I could lose a great deal of weight but my body for the most part is hour-glass figure except a little apple belly now ;( & puffy face and I wear a size 12/L so does this really make me close to obese – in my head it does

    Anyway my confidence is back which helps but I am still not 100 percent so any advice or constructive critism would be welcomed but did want to thank you for this article as it helped me to put this away as I decided to do what I know was always best instead of listening to people telling me to stop eating – that is the WORST thing anyone can do. I rarely eat bad I just put the fork down like an idiot told me to bring me down because of his own insecurities when I was secure prior GRRR but new fresh start ;D

  • http://mymassagetherapist.ca Sheila

    Anorexics are another example of the BMI myth…according to the BMI charts, people with this disorder are underweight HOWEVER if a measurement is taken to compare lean vs fat mass they are considered to be overfat given that the body will consume it’s muscle mass first during periods of starvation.

  • Joanne

    I am so happy to hear of the change, it is so important people learn this because either end of the scale we get wrong answers. I don’t believe it is any better for women than men however as said in 1 reply. I also would like to add that 1kg of muscle and 1kg of fat is the same, we need to abolish the notion that muscle weights more than fat because no matter how we want to look at it a kilo is a kilo. Yes the mass of each is much different in size! Too many people live with this false notion in their lives believing that 1kg of muscle weights more. Well done to you all who are and have achieved awesome fitness goals, I too am on a journey of health and fitness and plan to enjoy this life long journey with the hopes of becoming a trainer in some form. My PT Ryan is a great inspiration too me! Also thank you coach calorie for this site…Jo

  • Pooki9

    Finally!!! I had been privy to this information for a very long time as I have always carried an active lifestyle…perhaps, not quite as fit as these athletes, but, I stay fit on the regular with my routines of cylcing, hiking and going to the gym….Thank you for enlightening the rest of the folks out there!

  • http://www.facebook.com/diane.stamant.1 Diane St Amant

    I wish my nutrition teacher (who sight unseen insisted that I was obese) could/would understand this…. DOGMA isn’t helpful when universally applied

  • http://www.facebook.com/susan.l.powell.31 Susan Powell

    The BMI is a crock! I’ve always been muscular – my legs especially – When i got pregnant, I gained a lot of weight. However, in the past year, I’ve dropped 100+ plus where i was grotesquely obese at 259. I am now 151, feeling much better and more muscular than ever. In fact, I am wearing sizes less than I was before I got pregnant 19 years ago.

    Although I am 151 pounds, I look much better and skinnier than I did when I was 18.. However, I’m short at just 5’1″ tall… And, according to the BMI, I am near obese… According to that stupid thing, I should weigh around 115 pounds.. I never weighed that even BEFORE I had kids.. My goal is 130.. which is 10 pounds lighter than when I got pregnant those so many years ago.

    I do a lot of weight lifting so my arms and my legs are very muscular. My body frame is that of a man. I can out-bench, lift and run many men that I know.. But, i’m still near obese according to that stupid chart!

    And, my kids.. let’s not even get started… Those letters being sent home are just one step closer to more kids with eating disorders. And, the fact that insurance companies use it to charge people more money for being “overweight or obese” just pisses me off too!

  • http://www.facebook.com/amie.pejcic Amie Pejcic

    I get the same problem, Im 5″ 7″ i know im not as fit as i was. My BMI is 25 and im class as overweight, but my fat mass is 33percent.

  • http://www.coachcalorie.com/ Coach Calorie

    I think they are good to measure relative difference in skinfold measurements. They obviously won’t be the most accurate, but for the price they can’t be beat. I personally use the Lange calipers, but they are much more expensive.

    Kettlebell workouts are fine as long as you can add enough resistance and keep the intensity high. Anything that you enjoy and can push yourself with is a good choice.