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Originally Posted by Bintang
As for the 0.4kg threshold I’ve continued searching around for info since starting this thread and the only thing I have managed to find so far is the following statement from a health writer's blog:
"How Much Visceral Fat can I have before it causes health problems?
Research has demonstrated that when we look across the population and stuff everyone under the bell curve, a visceral fat area ranging from 10 to 100 cm2 is considered normal and at around 100 cm2 the risk for heart and metabolic problems begins to increase."
This is interesting but like so many blog statements it is not backed up by any references/citations. Also it refers to a threshold measure of visceral fat in terms of area (i.e. square centimeters, cm2). My DEXA scan results for visceral fat are reported in volume (cubic centimeters, cm3) and mass (kg). I have no idea how to relate the blogist’s threshold of 100cm2 to my DEXA result.
However, at least this information supports the notion that there is a threshold, which IS NOT zero.
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After a lot more googling, and reading I think I have found answers to my questions:
Researchers have indeed identified a critical level of visceral adipose tissue
(VAT) above which metabolic disturbances are likely to be found.
This threshold is 100 to 130 cm2 [Ref 1] with the lower value probably more pertinent to Asian populations - especially Japanese.
The threshold is stated as an area because most investigators use a single cross-sectional image as a representative measure of VAT volume and a compromise between accuracy and cost in their research [Ref 2].
However, VAT volume can be estimated from VAT area using correlations (eg. the following charts) from which it can be deduced that 100 to 130 cm2 of threshold VAT area must correspond to a
threshold VAT volume of around
2.4 to 3.0 liters, which is
~2.3 to 2.8 kg of VAT mass.
Now to another question.
How much visceral fat (if any) do young, healthy people have?
For some insight here is some data from Sweden [Ref 3]:
In the male group, with an age range of 14 to 66 years, the lowest measured VAT area was 14.6 cm2. This would correspond to a VAT volume of around 0.5 liter or a VAT mass of around 0.46 kg.
My DEXA scan visceral fat volume result of 1.09 liter (i.e. 1.03kg mass ) corresponds to a VAT area of only 41 cm2, which is way under the critical VAT threshold. At this point I have to conclude that my visceral fat level poses no risk and is more likely the kind of level that one would expect to see in a healthy person at least half my age.
So much for the advice of the DEXA scan physiologist.
And good luck to anyone my age who tries to follow her advice and reduce their visceral fat to below 0.4kg.
REFERENCES:
[1] Effects of diet and physical activity on adiposity and body fat distribution: implications for the prevention of cardiovascular disease.
https://www.ncbi.nlm.nih.gov/pubmed/19094306
[2] Visceral adipose tissue: relations between single-slice areas and
total volume
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC2040041/
[3] Practical approach for estimation of subcutaneous and
visceral adipose tissue
http://www.medsci.uu.se/digitalAsse..._112-joel-1.pdf