It would actually not be too far from the truth to insinuate that the high level of obesity in western societies including the United States is closely correlated to a growing trend of bad dietary practices especially the consumption of high-fat and high glycemic index carbohydrate foods. With the rate of eating out increasing by the day, the consumption of unhealthy calorie dense foods such as burgers and fries have become the order of the day.
Dietary fats are generally energy-dense foods with about 9 calories per gram and produces about twice the calories per gram of carbohydrate and protein. It is therefore easy to see why the amount of calories from consuming excessive fat-containing foods can quickly add up to very significant figures.
With all the negative criticisms and reviews about dietary fats in general, it would therefore seem that high-fat diets will do nothing more than cause obesity, cancer, and heart-related diseases. There is no gainsaying these facts as they remain true to a large extent but however cease to be if there is a significant reduction in the amount of consumed carbohydrate foods to prompt a state of ketosis.
Essentially, this concept is what led to the development of what is today known as high-fat low-carbohydrate diet. Losing weight through a high-fat low-carbohydrate diet has been shown to lower triglycerides (a type of blood fat), decrease insulin resistance, and also lower blood pressure.
While the use of a high-fat diet to lose weight may sound more than paradoxical, it is nonetheless true. But then, how and what exactly makes this possible considering all the harmful effects of high-fat consumption?
To begin with, it would be important to first understand which food category has the propensity to actually cause the most body fat storage. Simple sugars and starches from carbohydrate-containing foods readily comes to mind as they are converted into fast burning energy in the form of glucose which is generally considered to be the body's preferred source of energy.
The liver cells are known to convert and store about one-third while the muscle cells about two-third of the available glucose in the bloodstream into a storage form known as glycogen (a mixture of glucose and water) which serves as the body's auxiliary energy source and which is only released when the body needs fast burning energy during any possible "fight or flight" situation. Any excess glucose in the bloodstream is however converted to and stored as fat in adipose tissues (fat cells).
The storage of glucose as fat in the body is made possible by a hormone known as insulin. Whenever there is too much glucose in the bloodstream, specialized cells in the pancreas secretes insulin which subsequently stimulates insulin receptors on cell membranes to absorb the excess glucose from the bloodstream and store it as fat within the cell. However, if insulin level remains constant or reduced to a certain extent, the body stops converting and storing glucose as fat. One of the impacts of a high-fat low-carbohydrate diet is therefore the reduction of insulin production caused by the reduction of carbohydrate consumption.
However, the main effect and in fact main objective of a high-fat low-carbohydrate diet is to induce a condition known as ketosis. Ketosis is a condition whereby the body is practically being forced into breaking down its fat stores as a means of generating energy to meet its energy requirements due to the low availability of glucose in the bloodstream. Ketosis occurs mostly during periods of prolonged starvation but can be induced when large amounts of fats or proteins are eaten in the absence of carbohydrates.
Due to the low glucose level in the bloodstream resulting from reduced carbohydrate consumption, the body has only two other alternatives available, fats and proteins, for its energy supply. Considering the fact that protein is not actually stored in the body in a combustible energy form as their resultant amino acids are metabolized within a few hours after digestion, protein is therefore generally viewed as an inefficient alternative source of energy for body especially in a state of ketosis. Consequently, the body turns to breaking down its fat stores in order to meet its energy requirements.
While ketone bodies (by-products of ketosis) are normally oxidized quickly to water and carbon dioxide and excreted in the urine, however, the overproduction occasioned by the increased fat metabolism initiated by the onset of ketosis increases the body's acidity level. In order to reduce the acidity level, the body uses more of its water reserves from cells to flush out the accumulated ketones. The resultant water loss easily reflects on the scale and is what initially shows as weight loss during the initial stages of utilizing a high-fat low-carbohydrate diet.
The combination of these three effects: the stable insulin levels occasioned by the reduced blood glucose level; the fat-burning state of ketosis; and the loss of water from body cells makes high-fat low-carbohydrate diets to generally cause rapid weight loss.
However, most high-fat low-carbohydrate diets defer in the amount of daily carbohydrate allowance but generally limit it to between 25 and 45 grams of carbohydrate per day at the beginning of the diet to induce the state of ketosis. Other than the initial phase of the diet that normally causes rapid weight loss because of the induced ketosis, most high-fat low-carbohydrate diets incorporate about three or more additional phases to achieve their weight loss effects.
While the first phase normally lasts for about two weeks and allows the fewest daily amounts of carbohydrates, the subsequent phases however steadily allow the increase in the amount of consumed carbohydrates until the dieter achieves his or her desired weight loss goals.
It is however important that dieters drink a lot of water whenever using a high-fat low-carbohydrate diet in order to avoid dehydration and also to flush out the accumulated ketones in the body. Equally, individuals with kidney problems should avoid using a high-fat low-carbohydrate diet because of the enormous strain that might be exerted on the kidneys in flushing out the ketone bodies.
Consequently, one of the major underlying principle of most high-fat low-carbohydrate diets is the assertion that it is not actually fat or even calories that lead to weight gain, but rather an inefficient or unhealthy insulin cycle.
However, most nutritionists are of the opinion that weight loss, whether through utilizing a high-fat low-carbohydrate diet or any other diet, is caused because of reduction in calories resulting from the elimination of an entire food group from the diet and not because of any metabolic change initiated by the diet itself.
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