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Check & Save Your Body Composition Details

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Activity Factor
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Daily Energy

Body Fat
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BMI - Body Mass Index

Body Mass Index

Your body weight status


Body Mass Index [BMI]

The BMI provides a good indication of overweight and obesity at population levels but may be totally misleading when applied to an individual.

However, like all the measurements in BodyCalculator, they need to be put into the context of the individual.

The BMI provides you with an indication that your weight is in a healthy range. The BMI takes into account not only your weight but also factors in your height as well.

BMI is not a direct measure of body fat but can identify whether you are overweight or obese. It is an indirect measure of adiposity. It is a statistical measure and thus cannot predict health as such but we do know that being overweight and in particular being obese puts you at risk for many diseases including heart disease, diabetes and importantly many cancers.

Check where your BMI fits on the chart above [Click to enlarge and use the close button on the graph itself]

Being underweight is also not healthy. So if your BMI is in the overweight or obese range or higher, please discuss the options with your general practitioner. The weight management diet found on this website can help you either to increase your weight or to lose weight based on sound nutritional principles and strategies.

Limitations of the BMI

There are two important shortcomings with the BMI  

1] Overestimation of adiposity [body fat] if you have a muscular build or if your skeletal frame is heavier as may be the case in athletes or body-builders. 

The BMI discriminates against the individual with a mesomorphic build [usually males] i.e. an individual with large bones, solid muscular build, low body fat levels, wide shoulders with a narrow waist. Individuals like this and elite athletes with body fat percentages of 3% - 5% are often classified as obese using BMI values.

2] Underestimation of adiposity [body fat] in those with less lean muscle mass or weak skeletal frames such as the elderly where the weight is lower making the BMI lower.

The elderly can also lose height but may stay at the same weight they always had. The lower the height, the higher the BMI.       

Body Fat %

Click to enlarge

Body Fat Percentage

More info

Methods to determine body fat percentage

Many methods are used to calculate body fat percentage. More accurate methods such as Dual energy X-ray absorptiometry [DXA] involve X-rays or more complicated methods can be used such as determining body density by hydrostatic weighing [weighing a body underwater] or Computerized Tomography [CT]. But are these practical? Who has the time? Who would be willing to subject themselves to X-rays or the radiation of CT-scanning or being immersed in a tank of water?

There are numerous equations that can be used to calculate body fat percentage. These are are used in the many machines on the market that calculate body composition. Machines use Bioelectrical Impedance Analysis where a small electrical current is sent through the body.

The NutriDesk body fat percentage calculations

The calculations used to determine body fat percentage [BF%] on this website have prediction errors that are comparable to the prediction errors obtained by methods such as the use of skinfold thickness measurements or bioelectrical impedance. (Deurenberg, Weststrate et al. 2007)

Important facts about the formulas

  • 521 males and 708 females, were assessed and these individuals had a wide range of body mass index measurements (BMI; 13.9-40.9 kg/m2)
  • Ages ranged from 7-83 years. Individual body composition was determined by densitometry and anthropometry.
  • Body fat percentage was determined densitometrically and a formula using gender, BMI and age was developed to mathematically calculate body fat percentage.
  • Cross-validation of the prediction formulas revealed that valid estimates could indeed be produced by these formulas in males and females across all ages.
  • Overestimated body fat percentages was noted in obese subjects with these formulas.
  • Prediction errors as mentioned above were comparable with other methods used to determine body fat percentage such as skin fold thickness measurements or bioelectrical impedance.

Limitations of the formulas

  • Body fat percentage [BF%] can vary considerably at any constant body mass index [BMI]
  • Remember that these equations fit populations not the individual. A  valid example is a 55 year old, post-menopausal woman who frequents a gym regularly, engages in heavy weight training, has high lean muscle mass and low adiposity. This woman will have  body composition parameters that will almost certainly differ from that calculated by the equations used in BodyCalculator including BMI. The question that needs to be asked in this circumstance is how many post-menopausal body builders do you come across in daily life with absolutely lean and 'ripped' muscles indicating a very low body fat percentage?---This may be a valid example but in reality is very rare. Thus a post-menopausal woman in all probability is likely to have body composition parameters very close to that calculated for age, gender and BMI as used in the NutriDesk 'BodyCalculator'


  • Deurenberg, P., J. Weststrate, et al. (2007). "Body mass index as a measure of body fatness: age-and sex-specific prediction formulas." British Journal of Nutrition 65(02): 105-114.
  • Jackson AS, Stanforth PR, Gagnon J, et al. The effect of sex, age and race on estimating percentage body fat from body mass index: the Heritage Family Study. Int J Obes Relat Metab Disord, Jun 2002;26(6):789-96
Waist Circumference

Waist Circumference

Strong indicator for diabetes, heart disease & cancer risk

How well do you measure up?

There is a strong correlation between central adiposity [big waist] and
cardiovascular disease, hypertension, insulin resistance, the metabolic syndrome, Type-2 diabetes mellitus [T2DM], and many cancers.

The absolute waist circumference is a sensitive marker that could indicate you may not be as well as you think.

Changes occur at the molecular and vascular [blood vessel] level, long before you have symptoms or signs of disease. Having a large waist is the beginning of this metabolic and molecular change that sets you on your journey to a range of diseases that well and truly shorten your lifespan and quality of life. It is important to note that you cannot feel these early molecular changes - for all intents and purposes, you will function normally while these changes work in the background to clog your arteries and damage your organs.

The indicator above shows if you are at risk.

Pacific Islanders and Asian Populations

Please indicate if you are of Pacific Islander or Asian origin as the end-points are quite different in these ethnic groups and the indicator on this website can adjust for this automatically.

If your waist circumference is in the red section, you should consider discussing this with your general practitioner to see if blood tests for lipids [cholesterol, triglycerides, HDL, LDL], fasting blood glucose, kidney function and even fasting insulin levels are worth doing and to check your blood pressure to make sure you are not suffering from hypertension.

Where do I place the tape measure?

For both men and women, the 'waist circumference should be measured in a horizontal plane, midway between the inferior margin of the ribs and the superior border of the iliac crest.' [General Practice. Volume 8, Oct 2008. Elselvier]

In the graphic opposite, the tape measure is in the correct position --- simply find the lowest rib and then find the bony pelvic rim. The woman in the graphic on the left has her left index finger on this pelvic rim --- this gap is only about 8 cm wide. Remember keep the tape measure in the horizontal plane as shown in this graphic and not at an angle.

The deadliest diseases are often silent!

A fatal mistake of many individuals is to assume that because they feel well that they must be healthy. Diseases such as diabetes and hypertension [high blood pressure] are known as 'silent killers' why? because with these diseases you often feel 100% well, at least until that one fateful day when something goes wrong with your health that will change your life dramatically. This could be a stroke or kidney failure, a heart attack or the possibility of losing a limb due to gangrene. This simple measurement could indicate that you have changes in your blood or changes in receptor sensitivity such as insulin resistance, that will shorten your lifespan significantly. Some of the deadliest statements made are that you have a 'touch' of this or a 'mild' elevation in that. Any abnormal change in blood chemistry will lead to a slippery-slide towards cardiovascular disease unless you change your diet and lifestyle.

Your family history is important

Your family history is an important factor to take into consideration. If there is a history of heart disease, blood pressure or diabetes in the family, especially if these family members developed health problems early in life, then an increased waist circumference [central adiposity] is a strong indicator that you are at increased risk for one of these disease states.

Remember central adiposity also increases your risk for many cancers and chronic inflammation.

The NutriDesk 'Weight Management Diet'

Please have a look at the NutriDesk 'Weight Management Diet' if your waist circumference is in the range that is of concern. This diet not only targets your weight effectively if followed correctly, but provides you with a great insight into the many concepts, strategies and in-depth nutritional knowledge to ensure you have an optimal diet.

Calculate your waist-to-height ratio 

You do this by dividing your waist measurement by your height. If your waist is 81 cm and your height is 168 cm then your waist-to-height ratio is 81/168 = 0.48. A ratio of less than 0.50 is considered healthy.


Comparative Lean Body Mass

Comparative Lean Body Mass

Comparative LBM

Interpretation of the results

Good Level of lean body mass [muscle, bone, organ mass] - good protein reserves.

Possible Loss of lean body mass - always assessed within the clinical context of an individual - clinical scenarios below.

Close to the red. Precarious. Limited protein reserves. Rapid protein loss may occur in a clinical crisis such as acute trauma, post-surgery, acute illness such as an influenza infection or acute-on-chronic illness.

Comparative lean body mass as a screening tool for protein deficiency

This is a screening tool for the possible loss of lean body mass or Protein Energy Under-nutrition [PEU]. There is no such thing as a good or a bad test. All tests whether blood tests, radiology or any body composition measurement is subject to error both technical and biological.  What every doctor is trained to do is put a particular figure into clinical context - the question to be asked is whether the result is consistent with an individual’s medical circumstance.

When assessing a particular result, care must be taken when dealing with extremes such as elite athletes who often have very low body fat percentages or stocky individuals with large muscle mass.

Comparative lean body mass involves calculating:

  1. Minimal Lean Body Mass [MLBM] - this is the minimal lean body mass compatible with good health. This is based on a Body Mass Index of 20 [BMI = 20] and a Body Fat Percentage of 18 [BF% = 18] in females and a Body Fat Percentage of 10% [BF% = 10] in males. These values are based on numerous epidemiological studies (Wilmore, Buskirk et al. 1986)
  2. Current Lean Body Mass [CLBM] - Calculating the individuals lean body mass as it stands at the time of the calculation [present time].

      Comparative LBM = CLBM - MLBM
  • A Current Lean Body Mass [CLBM] that is less than the Minimal Lean Body Mass [MLBM] will produce a negative result and is a possible indication that there is lean muscle mass loss below that considered for optimal health in the average individual.
  • This is termed Protein Energy Under-nutrition or PEU (previously Protein Energy Malnutrition --- Merck Manual for Healthcare Professionals:

Is a negative result valid? --- all tests and calculations need to be placed in clinical context!

  • As mentioned above, this figure needs to be placed in the context of an individual’s medical history.
  • Lean muscle mass loss should be considered a possibility in individuals who have one or more of the following in their clinical history.
  • If a patientt has any one of the factors below or combination of factors then the higher the probability that this result accurately reflects protein energy under-nutrition with poor protein reserves in the event of a clinical crisis.

Sarcopenia --- Please also view NutriDesk QuickGuide: Sarcopenia

  • Individuals with a poor diet --- carbohydrate-rich, sugar-rich, fat-rich and protein poor [quite a large number of individuals in western cultures]
  • Individuals suffering from a severe acute and prolonged illness
  • Those with thyroid illness particularly hyperthyroidism [rapid metabolic rate] resulting in protein catabolism [breakdown]
  • Individuals who suffer from recurrent infections or have a chronic infection such as HIV
  • Individuals who feel constantly tired. An extremely common symptom of protein energy under-nutrition is constant lethargy.
  • Elite athletes or the serious exerciser – the need for protein increases significantly where demand for amino acids can outstrip supply if the diet is inadequate. The body will rob skeletal muscle, organs and bone for the supply of amino acids it needs for repair or synthesis of enzymes, neurotransmitters, receptors etc.
  • Chronic Illness of any kind – diabetes, renal disease, liver disease or cardiovascular disease or neurological disease affecting swallowing.
  • Being old and infirm - weak atrophied muscles and skeletal frames.
  • An impaired ability to exercise will result in sarcopenia [muscle loss and atrophy]
  • An individual suffering from serious illness or recovering from trauma
  • An individual convalescing from major surgery where protein needs can jump 50 – 100% (Demling RH 2003)
  • Pregnancy or lactation can greatly increase demand for protein.
  • Individuals with low androgen levels will have decreased lean muscle mass due to impaired synthesis of protein.
  • Individuals with a poor food intake [illness, anorexia, bulimia, elderly, individuals who are depressed or have a mental disorder such as schizophrenia]
  • Anyone addicted to drugs or alcohol.
  • Those on very restrictive diets such as vegan diets
  • Individuals who use of powerful antacids regularly such as proton pump inhibitors [omeprazole, pantoprazole etc.] which powerfully suppress hydrochloric acid [HCl] secretion. Hydrochloric acid is critically needed as the first step in pepsinogen activation and protein digestion.
  • Individuals undergoing treatment with steroids or chemotherapeutic agents that can impair digestion or protein synthesis.
  • Individuals who have had gastrointestinal surgery
  • Those suffering from malabsorption due to Coeliac Diasease, pancreatic disease or inflammatory bowel disease [Crohns or Ulcerative Colitis]
  • Individuals who have ulcers or bed sores that are healing poorly.


  • Demling RH, D. L. (2003). Involuntary Weight Loss and Protein-Energy Malnutrition: Diagnosis and Treatment. Medscape:
  • Wilmore, J., E. Buskirk, et al. (1986). "Body composition-a round table." Phys Sportsmed 14(3): 144–162.
Estimated Daily Energy Requirement
0 Cal = 0 kJ = 0 MJ   

Estimated Daily Energy Requirement

More info

  • The Basal Metabolic Rate [BMR] is the amount of energy required by the human body at rest and in the post-absorptive [fasting] state that is required for the functioning of vital organs such as the heart, liver and the central nervous system.
  • The BMR needs to be multiplied by what is called the Physical Activity Level or PAL to arrive at an energy intake that is required for an individual's level of activity --- e.g. whether they have a sedentary job or are serious exercisers or perform tasks as a manual labourer.
  • For simplicity's sake, the PAL in NutriDesk is simply called the 'Activity Factor'.
  • According to the NHMRC Nutrient Reference Values for Australia & New Zealand,  "For adults, a PAL above 1.75 is considered by some authorities to be compatible with a healthy lifestyle (FAO:WHO:UNU 2004, FNB:IOM 2002)."
  • However, this may overestimate energy requirements in a society that is becoming increasingly sedentary as this PAL assumes regular and effective exercise. The default PAL in NutriDesk is 1.6 and this can be adjusted by choosing the following Activity Factors:

Activity Factors in NutriDesk

  • 'Low' = to a PAL of 1.4
  • 'Medium' = to a PAL of 1.6 [default]
  • 'High' = to a PAL of 1.8

How does NutriDesk determine Basal Metabolic Rate [BMR]

  • BMR can be calculated by using numerous complicated formulas each of which have their own strengths or weaknesses. The strength of the formula used by NutriDesk is that it was the same set of formulas [Schofield Equations] used by the Australian government's body --- the National Health & Medical Research Council [NHMRC] in the reference guide 'Nutrient Reference Values for Australia & New Zealand' to help professionals assess the dietary requirements of individuals in the Australian and New Zealand population.
  • Thus the BMR's that are calculated in NutriDesk can be measured against the tables found in this official reference document.

How accurate are NutriDesk's calculations against the NHMRC's Estimated Energy Requirements [EER] for adults?

  • An accurate match will be noted for all age groups but differences will be seen in the
    51 - 70 age group --- why?
    "The original Schofield equations (Schofield 1985) from which these tables were derived used 60+ years as the upper age category. For people aged 51–70 years, the estimates were derived by averaging those for the adults (31–50 years) and older (>70 years) adults."
  • NutriDesk uses the Schofield equations as outlined in the NHMRC Guidelines for Australia & New Zealand for individuals 31 - 60 years and > 60 years and does not use averaging.
  • As a result the calculations will produce lower energy requirements in this age group.
  • This middle-age to older age group are at high risk of progressing to overweight and obesity due to sedentary lifestyles and hormonal changes. Thus in this age group having a lower caloric intake is an advantage and we know by a multitude of epidemiological and animal studies that lower caloric intakes prolong life.
  • Remember, these calculations can only be estimates at best and approximate guides to  macronutrient quantities.
  • One cannot have a 'set and forget' mentality with regard to caloric intake.
  • These quantities will need to be adjusted on an ongoing basis for individual needs. This simply means an individual will commence a diet based on this quantitative approximation in NutriDesk and adjust as necessary over time for either weight gain or weight loss.


  • The limitations of using a formulaic approach is that it fits a group and not an individual. The disclaimer of the NHMRC's document mentioned above is the same as that of NutriDesk which states:
    "This document is a general guide. The recommendations are for healthy people and may not meet the specific nutritional requirements of all individuals. They are designed to assist nutrition and health professionals assess the dietary requirements of individuals and groups and are based on the best information available at the date of compilation."
  • Please click on the table to get a clearer idea of what your activity factor or PAL should be.

Click to enlarge

Can I save my results?

You sure can. Simply join NutriDesk [top] and you will be able to save your results to monitor your progress.


Click to enlarge


If your BMI is in the overweight range or above, discuss the Weight Management Diet with your General Practitioner.