Difference between revisions of "Cole 2000 BMJ"

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== From BMI to BME ==
 
== From BMI to BME ==
 
  ''Work in progress'' by [[Gnaiger E]] 2020-01-20 linked to a preprint in preparation on [[body mass excess |'''BME''']] and [[:Category:BME and mitObesity |'''mitObesity''']].
 
  ''Work in progress'' by [[Gnaiger E]] 2020-01-20 linked to a preprint in preparation on [[body mass excess |'''BME''']] and [[:Category:BME and mitObesity |'''mitObesity''']].

Revision as of 23:05, 20 January 2020

Publications in the MiPMap
Cole TJ, Bellizzi MC, Flegal KM, Dietz WH (2000) Establishing a standard definition for child overweight and obesity worldwide: international survey. BMJ 320:1240-3.

» PMID: 10797032 Open Access

Cole TJ, Bellizzi MC, Flegal KM, Dietz WH (2000) BMJ

Abstract: OBJECTIVE: To develop an internationally acceptable definition of child overweight and obesity, specifying the measurement, the reference population, and the age and sex specific cut off points.

DESIGN: International survey of six large nationally representative cross sectional growth studies.

SETTING: Brazil, Great Britain, Hong Kong, the Netherlands, Singapore, and the United States.

SUBJECTS: 97 876 males and 94 851 females from birth to 25 years of age.

MAIN OUTCOME MEASURE: Body mass index (weight/height(2)).

RESULTS: For each of the surveys, centile curves were drawn that at age 18 years passed through the widely used cut off points of 25 and 30 kg/m(2) for adult overweight and obesity. The resulting curves were averaged to provide age and sex specific cut off points from 2-18 years.

CONCLUSIONS: The proposed cut off points, which are less arbitrary and more internationally based than current alternatives, should help to provide internationally comparable prevalence rates of overweight and obesity in children.

PIP: This study aimed to develop an internationally acceptable definition of child overweight and obesity, specifying the measurement, reference population, and age and sex specific cut off points. Data on body mass index (weight/height) were obtained from 6 large nationally representative cross sectional surveys on growth from Brazil, Great Britain, Hong Kong, the Netherlands, Singapore, and the US. The study included 97,876 males and 94,851 females from birth to 25 years of age. For each of the surveys, centile curves were drawn that at age 18 years passed through the widely used cutoff points of 25 and 30 kg/sq. m for adult weight and obesity. The resulting curves were averaged to provide age- and sex-specific cutoff points from 2 to 18 years. The proposed cut off points, which are less arbitrary and more internationally based than current alternatives, should help to provide internationally comparable prevalence rates of overweight and obesity in children.


Bioblast editor: Gnaiger E

From BMI to BME

Work in progress by Gnaiger E 2020-01-20 linked to a preprint in preparation on BME and mitObesity.
Figure 1: BMI cutoff values as a function of age. The symbols are from Table 4 of Cole et al (2010), compared to the personalized BMI cutoff points derived from the concept of body mass excess, BME. BMI0.2 and BMI0.4 are the personalized BMI cutoff points for overweight and obese, calculated from the reference body mass, M° of the HRP, and the body mass thresholds as a function of height, 1.2M° and 1.4M°.
Cole et al [1] suggest BMI cutoff points which can be applied equally to Caucasian and Asian populations from 2 to 18 years, separately for girls and boys. Unfortunately, body mass and height are not reported separately.
The concept of the healthy reference population (HRP) and body mass excess relates the actual body mass, M, to the reference body mass, M°, at any given height in the HRP. BME cutoff points for overweight and obesity are at 1.2 and 1.4M° or BME of 0.2 and 0.4, respectively. The precision reference BMI° of the HRP increases with height (see Body mass excess [2]). Up to 13 years, girls and boys have the same height. The precision BMI° of girls and boys increases from about 15 to 18 kg·m-2 from 5 to 13 years. In the following years, boys continue to grow and BMI° continues to increase to 20.5 kg·m-2, whereas growth of girls ceases and their BMI° remains at about 19 kg·m-2. This pattern applies to the HRP, and the comparison of the HRP [3, 4] with the data from Cole et al [1] is based on the assumption that the same height for age applies to both populations.
The BMI cutoff values of Cole et al (2010) agree closely with the precision BMI cutoff values derived from the BME-concept between age 8 and 13 (Fig. 1). Cole et al (2010) use identical BMI cutoff values for women and men at the age of 18, 25 kg·m-2 for overweight and 30 kg·m-2 for obesity. This ignores the fact that (1) women are smaller than men (see Height of humans), and (2) the BMI increases with height independent of a trend towards overweight (see Body mass excess). This explains, why lower precision BMI cutoff values are predicted from the BME-concept for women than men (Fig. 1).
Below the age of 8 years, the allometric phase changes to different mass-for-height exponents in the HRP. This is not taken into account in the approach of Cole et al (2010), which explains why their suggested cutoff values continue to drop more steeply with diminishing age compared to the HRP and the corresponding precision BMI cutoff values (Fig. 1).
In summary, the BME cutoff values of 0.2 and 0.4 for overweight and obesity have several advantages over adjusted BMI cutoff points. BME cutoffs (1) are conceptually consistent, without first assuming an allometric exponent of 2 for the BMI and then adjusting the BMI cutoff point to take into account the fact that the actual allometric exponent of the HRP is different from 2, (2) apply equally to girls, boys and adult females and males, and (3) are easy to explain to the general public, since the values of the BME cutoffs make sense and are understandable: 20 % increased body mass at a given height for overweight; 40 % increased body mass at a given height for obese.


References

  1. Cole TJ, Bellizzi MC, Flegal KM, Dietz WH (2000) Establishing a standard definition for child overweight and obesity worldwide: international survey. BMJ 320:1240-3.
  2. Body mass excess
  3. WHO Multicentre Growth Reference Study Group (2006) WHO child growth standards based on length/height, weight and age. Acta Pædiatrica Suppl 450:76-85.
  4. WHO Multicentre Growth Reference Study Group (2006) WHO child growth standards: length/height-for-age, weight-for-age, weight-for-length, weight-for-height and body mass index-for-age: Methods and development. Geneva: World Health Organization:312 pp.


MitoPedia: BME and mitObesity

» Body mass excess and mitObesity | BME and mitObesity news | Summary |

TermAbbreviationDescription
BME cutoff pointsBME cutoffObesity is defined as a disease associated with an excess of body fat with respect to a healthy reference condition. Cutoff points for body mass excess, BME cutoff points, define the critical values for underweight (-0.1 and -0.2), overweight (0.2), and various degrees of obesity (0.4, 0.6, 0.8, and above). BME cutoffs are calibrated by crossover-points of BME with established BMI cutoffs.
Body fat excessBFEIn the healthy reference population (HRP), there is zero body fat excess, BFE, and the fraction of excess body fat in the HRP is expressed - by definition - relative to the reference body mass, M°, at any given height. Importantly, body fat excess, BFE, and body mass excess, BME, are linearly related, which is not the case for the body mass index, BMI.
Body massm [kg]; M [kg·x-1]The body mass, M, is the mass (kilogram [kg]) of an individual (object) [x] and is expressed in units [kg/x]. Whereas the body weight changes as a function of gravitational force (you are weightless at zero gravity; your floating weight in water is different from your weight in air), your mass is independent of gravitational force, and it is the same in air and water.
Body mass excessBMEThe body mass excess, BME, is an index of obesity and as such BME is a lifestyle metric. The BME is a measure of the extent to which your actual body mass, M [kg/x], deviates from M° [kg/x], which is the reference body mass [kg] per individual [x] without excess body fat in the healthy reference population, HRP. A balanced BME is BME° = 0.0 with a band width of -0.1 towards underweight and +0.2 towards overweight. The BME is linearly related to the body fat excess.
Body mass indexBMIThe body mass index, BMI, is the ratio of body mass to height squared (BMI=M·H-2), recommended by the WHO as a general indicator of underweight (BMI<18.5 kg·m-2), overweight (BMI>25 kg·m-2) and obesity (BMI>30 kg·m-2). Keys et al (1972; see 2014) emphasized that 'the prime criterion must be the relative independence of the index from height'. It is exactly the dependence of the BMI on height - from children to adults, women to men, Caucasians to Asians -, which requires adjustments of BMI-cutoff points. This deficiency is resolved by the body mass excess relative to the healthy reference population.
ComorbidityComorbidities are common in obesogenic lifestyle-induced early aging. These are preventable, non-communicable diseases with strong associations to obesity. In many studies, cause and effect in the sequence of onset of comorbidities remain elusive. Chronic degenerative diseases are commonly obesity-induced. The search for the link between obesity and the etiology of diverse preventable diseases lead to the hypothesis, that mitochondrial dysfunction is the common mechanism, summarized in the term 'mitObesity'.
Healthy reference populationHRPA healthy reference population, HRP, establishes the baseline for the relation between body mass and height in healthy people of zero underweight or overweight, providing a reference for evaluation of deviations towards underweight or overweight and obesity. The WHO Child Growth Standards (WHO-CGS) on height and body mass refer to healthy girls and boys from Brazil, Ghana, India, Norway, Oman and the USA. The Committee on Biological Handbooks compiled data on height and body mass of healthy males from infancy to old age (USA), published before emergence of the fast-food and soft-drink epidemic. Four allometric phases are distinguished with distinct allometric exponents. At heights above 1.26 m/x the allometric exponent is 2.9, equal in women and men, and significantly different from the exponent of 2.0 implicated in the body mass index, BMI [kg/m2].
Height of humansh [m]; H [m·x-1]The height of humans, h, is given in SI units in meters [m]. Humans are countable objects, and the symbol and unit of the number of objects is N [x]. The average height of N objects is, H = h/N [m/x], where h is the heights of all N objects measured on top of each other. Therefore, the height per human has the unit [m·x-1] (compare body mass [kg·x-1]). Without further identifyer, H is considered as the standing height of a human, measured without shoes, hair ornaments and heavy outer garments.
MitObesity drugsBioactive mitObesity compounds are drugs and nutraceuticals with more or less reproducible beneficial effects in the treatment of diverse preventable degenerative diseases implicated in comorbidities linked to obesity, characterized by common mechanisms of action targeting mitochondria.
ObesityObesity is a disease resulting from excessive accumulation of body fat. In common obesity (non-syndromic obesity) excessive body fat is due to an obesogenic lifestyle with lack of physical exercise ('couch') and caloric surplus of food consumption ('potato'), causing several comorbidities which are characterized as preventable non-communicable diseases. Persistent body fat excess associated with deficits of physical activity induces a weight-lifting effect on increasing muscle mass with decreasing mitochondrial capacity. Body fat excess, therefore, correlates with body mass excess up to a critical stage of obesogenic lifestyle-induced sarcopenia, when loss of muscle mass results in further deterioration of physical performance particularly at older age.
VO2maxVO2max; VO2max/MMaximum oxygen consumption, VO2max, is and index of cardiorespiratory fitness, measured by spiroergometry on human and animal organisms capable of controlled physical exercise performance on a treadmill or cycle ergometer. VO2max is the maximum respiration of an organism, expressed as the volume of O2 at STPD consumed per unit of time per individual object [mL.min-1.x-1]. If normalized per body mass of the individual object, M [kg.x-1], mass specific maximum oxygen consumption, VO2max/M, is expressed in units [mL.min-1.kg-1].


Labels: MiParea: Gender, Developmental biology, Exercise physiology;nutrition;life style  Pathology: Obesity 

Organism: Human 

Preparation: Intact organism 




BMI, BME