Metabolic Effects of the Very-Low-Carbohydrate Diets: Misunderstood "Villains" of Human Metabolism

Abstract

During very low carbohydrate intake, the regulated and controlled production of ketone bodies causes a harmless physiological state known as dietary ketosis. Ketone bodies flow from the liver to extra-hepatic tissues (e.g., brain) for use as a fuel; this spares glucose metabolism via a mechanism similar to the sparing of glucose by oxidation of fatty acids as an alternative fuel. In comparison with glucose, the ketone bodies are actually a very good respiratory fuel. Indeed, there is no clear requirement for dietary carbohydrates for human adults. Interestingly, the effects of ketone body metabolism suggest that mild ketosis may offer therapeutic potential in a variety of different common and rare disease states. Also, the recent landmark study showed that a very-lowcarbohydrate diet resulted in a significant reduction in fat mass and a concomitant increase in lean body mass in normal-weight men. Contrary to popular belief, insulin is not needed for glucose uptake and utilization in man. Finally, both muscle fat and carbohydrate burn in an amino acid flame.

A low-carbohydrate survey: Evidence for sustainable metabolic syndrome reversal

“…74 For example, misunderstanding about the body's need for glucose, in particular by the central nervous system, continues despite basic scientific knowledge to the contrary. 5 In concert, the ADA does not recommend a low-carbohydrate diet for diabetes management. While recognising that 'carbohydrate intake has a direct effect on postprandial glucose levels' and 'total amount of carbohydrate eaten is the primary predictor of glycaemic response', the ADA advises that 'a variety of eating patterns (combinations of different foods or food groups) are acceptable for the management of diabetes' and recommends adjusting carbohydrate intake to mealtime insulin dosing.…”

“…4 The CDC's review of 2015 data reported more than 114 million Americans have diabetes or pre-diabetes. 5 While the rate of new diagnoses remains steady, the report noted that 9.4% (30.3 million of the 114 million estimated) of the US population has diabetes -an increase from 29.1 million in 2014. Countries with historically low diabetes rates are also now affected: almost half the population of China has pre-diabetes, and 10% have the diabetes.…”

A high-fat diet is deleterious to mice under glycolysis restriction

“…It has been debated whether lipid combusts in a flame of carbohydrate (Manninen 2004). Our data suggest that glycolytic pathway plays an important role for the lipid-metabolism to maintain the physiological responses.…”

An aquatic vertebrate can use amino acids from environmental water

“…Among the five amino acids that exhibited large effects, lysine, phenylalanine, and tyrosine are ketogenic amino acids, which can be converted to fatty acids in starvation-stressed organisms [33], and lysine, threonine, and phenylalanine are essential amino acids, ones that animals must obtain from their diet [34]. By contrast, alanine, proline, and glycine, which exhibited a small effect on growth, are neither ketogenic nor essential amino acids.…”