Tue, May-27-03, 02:33
Plan: Atkins maintenance
Location: Brisbane, Australia
Fascinating stuff about the way dietary fat CANT become body fat. Doreen and ... sorry, Andy I think.... you are a thrilling read.
I'm really curious about the people who stall on Low Carbing , even the people who keep their dietary carbs way low. So I've been doing a bit of reading myself about the way both protein and fat can be ( to varying degrees ) converted to glucose (ie. carbs) by :
(a) in the case of DIETARY protein: gluconeogenesis
(b) in the case of DIETARY fat : the glycerol pathway (I'm sure there's a noun for this, perhaps glycerogenesis ? - help!)
Gluconeogenesis is by far the more efficient of these two mechanisms , apparently , - up around 70 % ie. 1 complete protein gram= .7 of a gram of glucose
' glycero- genesis ' (sic) is apparently not nearly as efficient, something like 10 %. Looking for evolutionary ( or God motivated - if you're so inclined) reasons for this difference , it would seem that because ketones ( ie. the other way dietary fat is used metabolically) can provide all the energy needs of the body, including all but a very small amount of glucose required by the brain, you don't actually need ANY carbohydrates to be perfectly healthy. This is probably why dietary fat to satisfy energy needs and appetite is THE best way to lose weight ( and live a whole lot longer into the bargain, because insulin - the aging and body fat depositing hormone- is not asked to the metabolic party
So I wonder if the glucose provided by protein (gluconeogenesis) has exactly the same insulin ( and thereby body fat deposit) triggering effect as dietary glucose (carbs) For that matter glycero-genesis (sic) would be the same , but because it's so much less efficient , in the absence of dietary carbs, most of the resulting glucose would probably be snapped up by the brain , thus keeping it off your waistline!
The obvious implications of these gluconeogenesis and glycero-genesis factors for weight loss is that to a lesser extent than dietary carbs and to a far lesser extent than dietary protein, dietary fat provides very few metabolic carbs.
The human body is so clever at depositing fat ( with obvious survival advantages ). Except with dietary fat . Good news for people who want to lose weight. People who are fed up with the ' boring ' food choices on Atkins induction and are stalled in their weight loss anyway could try reducing their protein intake and doing more weights . The tissue building and rebuilding requirements of anaerobic (ie. weights) exercise snap up the available amino acids leaving fewer for gluconeogenesis. Aerobic exercise has countless cardiovascular benefits , not to mention the stress reducing effects. But as a way to lose weight it's like shutting the gate after the horse has bolted.
By the way, I for one, am really prone to being constipated . A daily teaspoon of psyllium husks will make anyone comfortably regular . The capsules are useless for the hard cases - like me. There just isn't enough fibre in them. Unless I suppose , you swallowed ten at a time - very expensive , surely!
So Doreen and Andy, make this unintelligble rave about gluconeogenesis and glycero-genesis (sic) accessible to all those stalled low carbers out there. Carbohydrate (glucose) is and always was the essential ingredient in putting on weight. But dietary carbs are not the only villain. Our bodies simply have more insidious ways of coming up with metabolic glucose.