Wednesday, April 27, 2011

Mike Eades on Becoming a Fat Burning Machine

When first thrown wholly upon a diet of reindeer meat, it seems inadequate to properly nourish the system and there is an apparent weakness and inability to perform severe exertive, fatiguing journeys. But this soon passes away in the course of two or three weeks. At first the white man takes to the new diet in too homeopathic a manner, especially if it be raw. However, seal meat which is far more disagreeable with its fishy odor, and bear meat with its strong flavor, seems to have no such temporary debilitating effect upon the economy.

These anecdotes of those thrown into life with the inuit and other paleo cultures are always fascinating and myth busting.  Why does it take a few weeks to adapt to a high meat/fat diet?  Mike Eades provides a no-nonsense description:
Someone who has been on a high-carb diet–the standard American diet, for example–has to metabolize a lot of sugar. All metabolic processes require enzymes to carry them out. Our DNA codes for these enzymes, but we don’t make them unless we need them. And when we do need them it takes a while for them to get brought up to the necessary levels. So, when we’re on a high-carb diet, we’ve got a lot of sugar-metabolizing enzymes kicking around, ready to metabolize sugar. All the sugar-metabolizing pathways are working efficiently.

Suddenly we switch to a low-carb diet. Now we don’t have much sugar to be metabolized–we’ve got fat instead. But our fat metabolizing pathways are kind of rusty. We’ve got plenty of sugar enzymes, but not enough fat enzymes. The body stays put for a bit to see what’s going to happen. Is this just a few hours without carbs or is it a real low-carb diet for sure? Once the body gets serious, signals go to the DNA, which starts coding for the fat-burning enzymes. They are soon made and start to work, and the fatigue goes away because the body can now efficiently metabolize fat, the main fuel on a low-carb diet.

Can you see how it makes sense that eating a high fat, low carb diet results in less fat in the blood?  In short, on a high carb diet, the body has a continuous problem of how to dispose of all the excess sugar.  Some is stored as glycogen, some is converted to fat in the liver, and some is consumed to run the body.  As the liver is working over time to convert sugar into fats (triglycerides), the body cannot burn those fats; it's too busy burning as much sugar as possible.  A low carb eating, fat adapted paleo man on the other hand, is running the majority of their cells on fat.  To sustain stable blood sugars, that same person will convert protein to glucose, and fats to ketones.  In other words, a sugar adapted sugar eater has fats floating aroudn all the time but cannot utilize them, whereas a fat adapted low carber is constantly burning fats for fuel and nearly always on the low side on sugars (which isn't a problem, it's good!). 

No comments:

Post a Comment