Ask:

I’ve heard that people on low-carb diets start out feeling without energy, because the body is still accustomed to providing energy through glycolycis, but later in the diet have plenty of energy to spare. If it’s not glycolysis that’s providing the energy(how could it be, where is the glucose) then what is it?

Answer:

Glucose provides quick energy but dietary fats provide sustained energy. Coconut oil if the only fat that provides quick energy just like a carb but without insulin or blood sugar reactions.

The core of Atkins program is converting the body from glycolysis (burning glucose as fuel) to ketosis (burning fat as fuel). Dietary fat levels need to be at >65% of total calories, if not, the body will still remain in glycolysis by converting 58% of excess protein into glucose (via gluconeogenesis).

Glucose is the bodies preferred fuel (if you want to get technical, it actually burns alcohol most efficiently, but that doesn’t make it any healthier for the body than carbs), the body can convert 100% of carbs, 58% of protein & 10% of dietary fat into glucose. The body can also be fueled by fat (dietary fat & fat cells) but only in the absence of carbs. Your brain actually prefers* to be fueled by ketones (part of the fat burning process), it does require glucose also, but glucose can be easily converted from excess protein if needed or dietary fat.

I think that ketosis is not the back up fuel plan. I think ketosis was meant to be primary fuel plan, that is easily overridden (one bite) by ingestion of carbs (or alcohol). The body is rarely allowed to become fully fat adapted, especially in these days of people using processed food formula to feed infants instead of breast milk. Carbs were never supposed to be available year around, only seasonally during harvest. The body can easily handle carbs even in excess occasionally, just not continuously. The body can also be fueled by protein (via gluconeogenesis) but long term protein synthesis creates the byproducts of ammonia & nitrogen. The body can easily handle clearing out these byproducts but if gluconeogenesis is used as the primary fuel source for long term, the body can be overwhelmed (poisoned) by the excess ammonia & nitrogen. It’s all contingent on balance but the body functions at optimal levels on more dietary fat & suboptimal levels on less dietary fat. Continue reading What process is the main energy provider in low-carb diets? →