By: Katie Mark
This article was originally posted on blog.insidetracker.com
InsideTracker is a health analytics company that tracks and analyzes key biochemical and physiological markers within our body. An elite team of scientists, nutritionists, and physicians break down the tests to provide key lifestyle and nutrition recommendations. Learn more at https://www.insidetracker.com/
If you could tap into >40,000 calories of your fat fuel during endurance exercise instead of relying on your maximum 2,000 calorie storage of carbohydrate fuel, would you do it? What if it meant no more liquid gels, sugar-containing sports drinks or bananas to give you that energy boost when you’re on the verge of exhaustion? If LeBron James did it was it really a wise choice based on current science?
Our customers wanted to get the science on the popular diet trends available, so we did the work for you. Instead of doing the typical and boring diet review one-by-one, we contrasted three similar eating options, with a focus on the ketogenic diet, a mainstream choice for some dieters. Users of InsideTracker want to know how to use common diet strategies to improve their goals, and specifically how biomarkers are affected by reducing carbohydrates and calories respectfully.
A ketogenic diet, or a diet high in fats and very low in carbohydrates, allows you to transition from energy dependence on carbohydrates to fats by breaking down fatty molecules into chemical compounds called ketones. The ketogenic diet was first developed by researchers to help treat seizures in children who suffered from epilepsy. Today some fitness enthusiasts and nutritionists are touting it as a valuable method for losing body weight and optimizing athletic performance.
However, how can the ketogenic diet help athletes such as Lebron James and someone in their mid-40s seeking to shed a few pounds? In this first part of a two-part blog series, we will explore the molecular basis of how energy generation, ketosis, and the physiological circumstances under which the body starts using ketones and fats as its primary energy source. Then, we will look at some of comparisons and controversies of the ketogenic diet and whether or not it is a valuable tool in losing weight. In the second part of the blog series we will explore in more detail how InsideTracker can help you monitor critical biomarkers such as HDL and LDL cholesterol, glucose, and testosterone if you decide to pursue a ketogenic diet – or any other diet regimen – and make appropriate dietary modifications to optimize these levels.
The Molecular Basis of Ketosis: Breakdown of Fats vs Carbs
In order to understand the scientific basis of the ketogenic diet we must first review some basic biochemistry. The human body generates its energy in the form of adenosine triphosphate – also known as ATP – through a process called cellular respiration. This process consists of three parts: glycolysis, the tricarboxylic acid cycle (also known colloquially as the “Krebs cycle”), and the electron transport chain. The first process, which occurs in the cell’s cytoplasm, converts the six-carbon sugar glucose into a small amount of ATP, some electron carriers which facilitate the transfer of energy, and two copies of a three-carbon sugar named pyruvate. These molecules of pyruvate then enter the mitochondria – the cellular structure that functions as the cell’s energy powerhouse- and converts each three-carbon pyruvate into a modified two-carbon sugar called acetyl coenzyme A (acetyl-CoA) and a molecule of carbon dioxide (CO2). The acetyl-CoA then enters the tricarboxylic acid cycle where it generates a small amount of ATP and additional electron carriers. In the final stage of cellular respiration called the electron transport chain, these electron carriers generated from glycolysis and the tricarboxylic acid cycle are used by the mitochondria to generate ATP through a mechanism called chemiosmosis. It is this stage where the bulk of energy (in the form of ATP) is generated in cellular respiration by the human cell.
Usually, the human cell starts cellular respiration by using the carbohydrate glucose in glycolysis. If glucose levels are low, the body will tap into its storage of carbohydrate glycogen and easily break it down into its glucose substituents. However, when both of the body’s energetically accessible carbohydrates are in low supply, it must rely on an alternative source to satisfy its energy demands. As a result, the body is said to enter a state called ketosis where it breaks down high-energy fat molecules called triglycerides abundant in adipose tissue. Triglycerides- which are composed of three fatty acids attached to a glycerol backbone – are broken down in mitochondria by a process called beta-oxidation where acetyl-CoA is ultimately generated. As previously mentioned, acetyl-CoA goes into the tricarboxylic acid cycle where it produces a small amount of ATP and electron carriers that generate more ATP in the electron transport chain. Thus, when triglycerides are broken down to acetyl-CoA they bypass glycolysis and directly enter the TCA cycle.
You can read the rest of this article at https://blog.insidetracker.com/ketogenicdiet