Lipid matters in men versus women

[Guest guest]

Hi All,

Men may be at greater risk from fasting than women, might be a consideration.

See the pdf-available below and its excerpt on fasting. Other differences are

plentiful between male and female metabolism of fats, it seems.

Mittendorfer B.

Sexual dimorphism in human lipid metabolism.

J Nutr. 2005 Apr;135(4):681-6.

PMID: 15795418

http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?cmd=Retrieve & db=pubmed & dopt=Abstra\

ct & list_uids=15795418

... The aim of this article is to review the major findings on differences of

human fatty acid and TG metabolism between men and women in the basal, overnight

fasted state and during the major physiologic challenges that affect lipid

metabolism, i.e., food intake and hyperinsulinemia/hyperglycemia, exercise, and

short-term fasting. Reference to women in the following sections refers to

premenopausal women unless specifically indicated otherwise.

... Fasting

The initial response to fasting is characterized by an increase in the

mobilization of adipose tissue TG and a decrease in the production and oxidation

of

glucose. Studies that were performed many years ago showed that the increase in

plasma fatty acid and ketone body concentrations (44–46) is greater in women

than in

men. These findings may at first suggest that the mobilization of fatty acids

from

adipose tissue is likely greater in women than in men during fasting. However,

plasma substrate concentration represents the balance between substrate delivery

into plasma and substrate tissue uptake but does not provide information

regarding

the dynamic metabolic events responsible for the observed concentrations. In

fact,

contrary to these earlier studies, we found that the relative increase in

glycerol

Ra during brief fasting was greater in men than in women, most likely because of

both higher basal plasma insulin concentrations and a greater increase in

epinephrine release during fasting in men (47). The relatively blunted lipolytic

response in women may be beneficial by preventing excessive and potentially

harmful

increases in plasma fatty acid concentrations (48).

...

Al Pater, PhD; email: old542000@...

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