Is Keto the way to go?

Well, this would depend on your health goal and foods you like. The data proves that weight loss will occur regardless if you eat a low carbohydrate diet or a low fat diet. Reducing calories from a single source of macronutrients will aid in weight loss. It’s important to consider the types of foods you enjoy and if they fit into the higher carbohydrates – low fat or higher fat – low carbohydrate model. The foods you tend to enjoy will help you stay focused on your diet. For example, if you like eggs, meats, dairy, nuts and seeds, then it would be wise for you to go low carbohydrate. However, if you like oatmeal, rice, potatoes, and pasta, then it would be wise to go low fat -higher carbohydrates. The best diet is the one you’ll end up sticking with. 

What is Keto? Keto is short for ketogenesis, which is the process of creating ketone bodies to serve as a fuel source if glucose levels are too low. It should be advised that ketone synthesis reaction yields HMG CoA, which is a precursor of cholesterol. This concludes higher elevations of serum cholesterol as a result of being on a low carb diet. The theory behind keto is by limited glucose by means of carbohydrates, then the body will processes fat to sustain energy balance. 

How does our body burn fat? 
    In order for our body to obtain energy from fat, our body will break down triglycerides into fatty acids and glycerol. This process is known as lipolysis, and fatty acids are oxidized by B-oxidation into acetyl CoA. Acetyl CoA is used by the Krebs cycle to generate energy. Triglyceride molecule yield more energy than carbohydrates and are an important source of energy. Organs such as the brain require glucose in order to function. However, the body can use ketones as an alternative energy source to keep the brain functioning when glucose is limited. If ketones aren’t used, then they can be broken down into CO2 and acetone. Acetone is removed by means of exhalation, which may cause the breath of an individual to have sweet breath like alcohol. The carbon dioxide produced can acidify the blood, and could lead to diabetic ketoacidosis. 

The problem is carbohydrates and Fat together

When glucose levels are complete, acetyl CoA generated by glycolysis is converted into fatty acids, triglycerides, cholesterol, steroids, and bile salts. Lipogenesis creates fat from acetyl CoA generated from the Krebs cycle an place in the cytoplasm of adipocytes (Fat cells)  and hepatocytes. (Liver cells)  It would be recommended to not consume too many calories from fat and carbohydrates at the same time. The theory behind is both contribute to fuel sources for the body, and when glucose is in abundance, then the body will store the excess as fat. 

Issues with Keto Diet? 

Data has shown favorable biochemical and physiological effects during weight loss periods. However, there’s been studies to record endothelial function, C-reactive Protein and fat during maintenance level.  High fat diets, like the one Keto promotes has been shown to increase low-density lipoprotein, increase visceral obesity and metabolic syndrome proving the long term effects may not be favorable. However, saturated fat might be the source of the problem compared to unsaturated fat. There’s also a problem for men due to lower resting testosterone and greater cortisol levels post physical activity. A low carbohydrate diet over a long period of time may cause greater affects on the endocrine system. What about for women? In a randomize cross over study, women had reduced exercise performance in activities on a keto diet. Ketogenesis is a process to supply glucose to the organs that require glucose, and limited studies have shown the long term effects of being in this state. Data suggest an increased risk for metabolic syndrome. 

What's best for performance

This also depends on the type of physique or style of training you prefer. If you want a smaller, lean physique then eating a low carbohydrate diet and higher fat might work better for you. A ketogenetic style diet will limit glycogen in the muscle making the muscle look flatter.  If you enjoy moderate to low resistance training, jogging, and walking, then lower carbohydrates may work better for you depending on your level of performance. A low-carb diet might not be suited for a strength athlete or a long distance runners. The primary reason for this logic is due to the metabolic pathway to process energy by means of ATP for use by the body to power physiological processes. Glucose is the body’s most readily available source of energy. After digestion, the body breaks down polysaccharides into monosaccharides, which are transported from the small intestines to the circulatory system or stores the excess as glycogen stored in the muscle cell. Since glycogen is the primary energy source for easily expenditure, it’s valuable during exercise and weight training. Building muscle in a ketogenetic state is counterproductive. Eating carbohydrates is valuable when considering carbohydrates with a low glycemic index. A glycemic index is a metric used to determine the rate of breakdown. Simple sugar is very high whereas oatmeal is low. 

The Break Down (Science)

Key organs require glucose to function including the brain, and therefore it’s essential to maintain a minimum blood glucose level. The breakdown of carbohydrates from whole food sources packet with fiber and phytonutrients is preferred, and carbohydrate metabolism is an extensive process called Glycolysis. glycolysis is rather complex exchange of phosphates molecules referred to as the Krebs cycle to produce 4 ATP molecules. Carbohydrate metabolism involves multiple processes such as glycolysis, Krebs Cycle, and the electron transport chain. 

During times of starvation or low carbohydrate diets, the liver is able to synthesize new glucose from pyruvate, lactate, glycerol, or amino acids alanine or glutamine. This process is known as Gluconeogenesis. 

How does the body breakdown fat? Lipid metabolism begins in the intestine where triglycerides are broken down into fatty acids and monoglyceride molecule by means of pancreatic lipases. 

Final Take

Data shows, at least for short term, keto diets are safe and effective for losing weight. However, a reduction of calories from all macronutrients is the preferred method for weight loss. Some data concludes an adherence to a keto-diet proving the diet to be less effective the longer someone stays on the diet. To take advantages of both lipid and carbohydrates metabolism, carbohydrate and fat cycling would be the best approach. Carb- cycling is the method for alternating between high carb – low fat either on a weekly or monthly cycle. Ketogenic diets may help aid in weight loss because it’s easier for people to avoid one macronutrient than focus on reducing calories from all sources. However, data proves that weight loss occurs at the same rate regardless of high fat-low carb or high carb- low fat. Similar to the source of carbohydrates, the source of fat may play a crucial rule in the prevention of cardiovascular disease. 

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