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[A1CR]

Fats are lost from the body during CR and fasting. It
appears that, from
the paper below and a previous http://tinyurl.com/k8frt
paper , that animals that may be subjected to colder
temperatures may
adjust their body fats to accommodate lower temperatures
during winter.
Might the response apply also to animals for which cold
winter temperatures
do not apply specifically, but reduce their body
temperatures as an
accomodation to the CR-induced lowering of body temperature?

Martin B, Mattson MP, Maudsley S.
Caloric restriction and intermittent fasting: Two potential
diets for
successful brain aging.
Ageing Res Rev. 2006 Aug 7; [Epub ahead of print]

PMID: 16899414 http://tinyurl.com/g9w73

The mobilization of fatty acids (FAs) during food
deprivation is a
selective process in laboratory rodents and humans. The
site-specific
differences in adipose tissue functions - e.g. energy
storage versus
insulation - should also affect the use of different FAs. To
study this, 16
female minks were randomly assigned into the control group
or fasted for 5
days. Preferential mobilization of n-3 polyunsaturated FAs
(PUFAs) during
fasting caused a decrease in the n-3/n-6 PUFA ratio in fat
and liver. In
addition, the minks utilized short-chain FAs efficiently in
all fat depots,
but long-chain FAs - 20:0, 20:1n-11, 20:1n-9, 22:1n-11 and
24:1n-9 - were
preserved. The number of double bonds in the FA chain
correlated positively
with mobilization rate in the retroperitoneal fat. The
observed negative
correlation between mobilization rate and the location of
the first double
bond from the methyl end may be due to peroxisomal
chain-shortening of
long-chain FAs and not the double bond position per se. As a
result, minks
are able to preserve a low melting point and fluidity of the
subcutaneous
fat depots, which would be essential to a Northern
semi-aquatic mammal.