Journal of Cachexia, Sarcopenia and Muscle
 The Author(s) 2012
10.1007/s13539-012-0058-6

Letter to the Editor

Not being able to see the muscle for the fat

Christopher J. OliverContact Information

(1)  School of Health and Human Sciences, Southern Cross University, PO Box 157, Lismore, NSW, 2480, Australia

Contact Information Christopher J. Oliver
Email: coliver@scu.edu.au

Received: 6 December 2011  Accepted: 11 January 2012  Published online: 23 February 2012


Without Abstract
This comment refers to the article available at: http://dx.doi.org/10.1007/s13539-010-0014-2.

At its simplest, we can express body weight or body composition as comprising of adipose tissue, muscle tissue and skeletal tissue. Body weight and body mass index (BMI) of populations of all ages have been increasing for close to half a century, leading to the present obesity epidemic. The causal pathways linking excessive body fat to serious chronic diseases, including diabetes and heart diseases is now well established.

A recent editorial citing body composition data from Li et al. [1] asked the question “Are Normal-Weight Americans Over-Fat?” [2]. This interpretation of the data from Li et al. reinforces an adipocentric view giving adipose tissue primacy; perhaps there is a different view, a sarcocentric view that proposes that people are perhaps becoming under-muscled rather than just over-fat. Data from Canada [3] and Germany [4] indicate that children and adults are getting fatter at the same body weight or BMI. If we are fatter at the same body weight and BMI then the other two tissues, muscle and or bone must be diminishing. Given that this increased body fatness at the same weight is most likely a proxy for decreased physical activity, it is a good bet that muscle is the tissue that has diminished most. The loss of muscle is of great physiological importance as proper-functioning muscle is responsible for most glucose disposal and required to stave off insulin resistance [5, 6]. Proper functioning muscle has been highlighted as important for longevity even after accounting for respiratory fitness and BMI [7].

Therefore it is important to remind those with an adipocentric perspective that a low body fat in itself is not necessarily healthy if it coexists with poor-quality muscle and bone. This is important given various body composition states such as metabolically normal obese individuals [8] and thin persons with significant ectopic fat [9]. We may have better health outcomes if we focus more on the causes and sequelae of body dyscomposition, especially the diminution of muscle mass and function even in the young, rather than assuming the problems of body composition in the general population largely lie in terms of adiposity.

The retention and maintenance of muscle and muscle function is coming under increasing scrutiny in our ageing society because of the looming epidemic of sarcopenia and the financial and social impact that this will have. However, the discussion around the diagnosis and prevalence on sarcopenia is centred on the target clinical population, i.e., the elderly [10]. Nevertheless, the data cited above from the USA, Canada and Germany studies highlight that on current form, a number of our children may not meet their genetic potential of muscle mass and by inference muscle function. The medium-term consequences of this muscle shortfall as a risk factor for type 2 diabetes alone is of concern; the longer-term consequences of any muscle shortfall to sarcopenia prevalence and its possible inception at a younger age should be of even greater concern. Those concerned with sarcopenia, including this journal, perhaps need also to focus more on prevention even starting with childhood.

The author of this manuscript certifies that he complied with the Ethical guidelines for authorship and publishing in the Journal of Cachexia, Sarcopenia and Muscle [11].
Conflict of interest  
Chris Oliver is Research Director for Blackmores Ltd, a nutraceutical company that has among its range, products for weight loss and a whey product for persons aged 50 years plus. The opinions expressed in this paper are the author's personal views.
Open Access  
This article is distributed under the terms of the Creative Commons Attribution Noncommercial License which permits any noncommercial use, distribution, and reproduction in any medium, provided the original author(s) and source are credited.


References

1. Li C, Ford ES, Zhao G, Balluz LS, Giles WH. Estimates of body composition with dual-energy X-ray absorptiometry in adults. Am J Clin Nutr. 2009;90:1457–65.
PubMed CrossRef ChemPort
 
2. St-Onge MP. Are normal-weight Americans over-fat? Obesity (Silver Spring). 2010;18:2067–8.
CrossRef
 
3. Janssen I, Shields M, Craig CL, Tremblay MS. Changes in the obesity phenotype within Canadian children and adults, 1981 to 2007–2009. Obesity (Silver Spring) 2011 May 12.
 
4. Nagel G, Wabitsch M, Galm C, Berg S, Brandstetter S, Fritz M, Klenk J, Peter R, Prokopchuk D, Steiner R, Stroth S, Wartha O, Weiland SK, Steinacker J. Secular changes of anthropometric measures for the past 30 years in South-West Germany. Eur J Clin Nutr. 2009;63:1440–3.
PubMed CrossRef ChemPort
 
5. Atlantis E, Martin SA, Haren MT, Taylor AW, Wittert GA. Inverse associations between muscle mass, strength, and the metabolic syndrome. Metabolism. 2009;58:1013–22.
PubMed CrossRef ChemPort
 
6. Srikanthan P, Karlamangla AS. Relative muscle mass is inversely associated with insulin resistance and prediabetes. Findings from The Third National Health and Nutrition Examination Survey. J Clin Endocrinol Metab. 2011;96:2898–903.
PubMed CrossRef ChemPort
 
7. Ruiz JR, Sui X, Lobelo F, Morrow Jr JR, Jackson AW, Sjostrom M, Blair SN. Association between muscular strength and mortality in men: prospective cohort study. BMJ. 2008;337:a439.
PubMed CrossRef
 
8. Primeau V, Coderre L, Karelis AD, Brochu M, Lavoie ME, Messier V, Sladek R, Rabasa-Lhoret R. Characterizing the profile of obese patients who are metabolically healthy. Int J Obes (Lond). 2011;35:971–81.
CrossRef ChemPort
 
9. Thomas EL, Parkinson JR, Frost GS, Goldstone AP, Dore CJ, McCarthy JP, Collins AL, Fitzpatrick JA, Durighel G, Taylor-Robinson SD, Bell JD. The missing risk: MRI and MRS phenotyping of abdominal adiposity and ectopic fat. Obesity (Silver Spring). 2012;20:76–87.
CrossRef ChemPort
 
10. von Haehling S, Morley JE, Anker SD. An overview of sarcopenia: facts and numbers on prevalence and clinical impact. J Cachexia Sarcopenia Muscle. 2010;1:129–33.
SpringerLink
 
11. von Haehling S, Morley JE, Coats AJ, Anker SD. Ethical guidelines for authorship and publishing in the Journal of Cachexia, Sarcopenia and Muscle. J Cachexia Sarcopenia Muscle. 2010;1:7–8.
SpringerLink