Originally Posted by esaunders

Ok guys, time for a little low-carb myth-busting.

1) The brain can run on Glucose or on Ketones which are produced by burning fat. The brain actually runs more efficiently with ketones but the 'modern' or agriculturally-based diet provides access to carbohydrate in sufficiant quantity that glucose is used first.

2) The kidney damage issue has been disproven for several years now but increased fluid intake is natural due to the diuretic nature of the diet. The diuretic effect is equivalent to that of 'water pills' as used for hypertension. (which means that those under drug treatment for hypertension need to communicate with their doctor when low-carbing as they may quickly end up over medicated)

3) The hypoglycemia symptoms result from an imbalance between blood glucose levels and insulin levels. In a healthy person, glucose does not drop to dangerous levels due to the liver's ability to generate glucose from non-carbohydrate sources. This is not an attempt to say that 'bonking' doesn't happen on low carb but that 'bonking' occurs when the body has not sufficiently acclimatized to a primarily fat-burning metabolism vs primarily carbohydrate-burning metabolism. There have been at least a couple good studies done comparing high-carbohydrate fueling for athletic performance vs low-carbohydrate fueling for athletic performance. In the early stages the result has been exactly as you all report. However, over time, the low-carb performance level improves to at least equal to the high-carb fueling

This leaves a person involved in high output athletic activities with 2 choices: A) increase carb intake in the diet to adjust for the increased activity B) Reduce athletic activity to comfortable level and permit the body time to adjust to the metabolic change of processing. Most people chose (A) however the second option is still available and effective.


I was reminded of this listening to an author on the radio recently. Anyone who's interested in the history of dietary dogma from a reasearch point of view might be interested in this book. "Good Calories, Bad Calories" by Gary Taubes. He's not a 'diet book' guy so it should be interesting reading.