Why Low Carbohydrate Diets
  Don’t Produce Long Term Results

by Larry North

   The high fat, low carbohydrate diet was very popular during the 1970s and was known as the Atkins Diet. After a couple of years of popularity, the Atkins dieting approach fell by the wayside for several reasons. Well, now it’s back and is popular again.
   The concept of Dr. Atkins’ diet is to consume high fat and low carbohydrates. This causes a quick drop in body fat and body water. The piece of the puzzle missing for most dieters is the long-term effects of such a drastic reduction in carbohydrates.
   Many books have revitalized the Atkins Diet. The concept is that a person should eat more protein, more fat and very little carbohydrates. Because the dieter is eating more fat, they tend to feel full longer, which helps the dieter exert more control over hunger. In the past, people were allowed to eat as much red meat as desired, but had to keep their carbohydrate intake as low as possible. This combination of foods causes a chemical reaction, thereby causing the person to burn body fat at an accelerated rate. The low intake of carbohydrates, coupled with a high fat diet and exercise causes the production of ketones. Ketones are the chemical residue of broken down fats in the blood. If insufficient carbohydrates exist, the body begins to mobilize fat to a greater extent than it can use. The result, at rest and after exercise, is incomplete fat metabolism and the accumulation of acid by-products called ketone bodies. This situation can lead to a harmful increase in the acidity of the body fluids, a condition called acidosis or ketosis. It was in the 1920s that doctors in France and the U.S. conceived the Ketogenic diet. They discovered that prolonged starvation promotes ketosis as the body uses its fat reserves. Thus, they were able to devise a way to mimic the chemistry of starvation through diet.
   Most people get their information from uninformed sources and fail to understand the scope of their recommendations. If you have started a high fat, low carbohydrate diet then here are a few things you should know.
   By reducing carbohydrates you will see a drop in body weight and body fat. However, if you reduce carbohydrates too low while exercising, you could alter your levels of T3. T3 is an active thyroid molecule that helps regulate your metabolic rate. Diets low in carbohydrates tend to cause a reduction of T3, which in turn can slow down your metabolic rate. This is particularly true for people who under eat and over-exercise.
   The weight dropped while on a low carbohydrate diet is water weight. This may sound like a good idea at the time, but when you resume eating carbohydrates you will find that your body rebounds and retains excess water. The water retention will dissipate after several days, but it wreaks havoc on the dieter’s mental state.
   Studies show that the longer a person has been on the low carbohydrate diet, the more carbohydrate sensitive they become. People who exercise and restrict their carbohydrate intake cause their bodies to become much more carbohydrate sensitive and this could be the most devastating pitfall. In other words, once the low carbohydrate diet has ended and the person tries to resume eating carbohydrates, their bodies tend to store the carbohydrates as opposed to using them for energy. The result is a fast accumulation of body water followed by an abnormally fast body fat gain. Although the water weight will eventually drop off, the person notices that they gain body fat very easily, but lose it more slowly on the next diet-go-round.
   Carbohydrates also provide a “protein sparing” effect. Protein serves as a vital role in the maintenance, repair and growth of body tissues. When carbohydrate reserves are reduced the body will convert protein into glucose for energy. This process is called gluconeogenesis. The high price of this process is paid in a reduction of the body’s protein stores, also known as muscle. The “protein sparing” process causes the metabolic rate to slow.
   Low carbohydrate levels tend to make muscles lose their density and flatten out. Carbohydrates are a great source of fuel. Not eating enough will lower your energy level.
   The focus on these diets is the relationship between carbohydrates and insulin, a hormone that shuttles fuel into fat. It is a very flawed theory that insulin exerts negative effects. Insulin plays an important role in fat storage and it also causes glucose to be shuttled into muscle cells as well. Our diets should keep blood levels of insulin as stable as possible.
   You would have to totally be out of the loop if you haven’t heard that more fat increases your risk of heart disease, cancer and obesity. We in the fitness industry disagree with the American Dietetic Association that 30% fat is healthy. A diet of 20% or less fat poses a substantial health benefit, as well as, a reduced risk of obesity.
   A diet of high protein, low fat and moderate carbohydrate produces some of the best physiques. Confusion about carbohydrates stems from the fact that people see and hear bits and pieces of information and accept the misinformation as fact. This is a far cry from cutting carbohydrates from lunch onward.
   The best approach to dieting when you hear people talking about a “new” diet is to stop and ask yourself if it follows healthy guidelines. Does the diet call for measures that you cannot fit into your lifestyle for the rest of your life? Be very skeptical and beware of products that suggest that a certain food or special combination of foods possess a “magical” or “special” property that will help you lose weight.

— As told to Larry North by nutrition expert Keith Klein

Larry North is President of Larry North Fitness. He may be contacted by phone at 214.526.6784 or via website at

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