Low Carb Diets Part 1
Low carbohydrate diets have been around for a very long time. Long before our civilization reached the agricultural stage, the availability of carbohydrates, especially grains, was fairly low. People survived on what was available in their surrounding environment. This included wild game, wild fish, wild fowl, wild fruits, wild berries, tubers and wild vegetables.
People who existed on 'survival' diets spent long periods of time in a state of semi-starvation, interspersed with random periods of intense feeding. This 'feed or famine' pattern went on until we began making and using tools, and learning to control the environment that we were once forced to submit to.
Eventually, we began to accumulate and store food, and were no longer subject to the random feeding patterns that plagued our hard-working for-parents. Gradually, feeding patterns became more and more regular, as our methods of food accumulation and storage became more and more sophisticated. People were still not obese, because they still had to work physically hard to survive.
Although it is far less extreme than the semi-starvation that our ancestors endured, people probably spent long periods of time in a state of chronic energy deficit, depending of course on the duration and intensity of the labour that was performed.
Ultimately, we have taken such complete control of our environment, that we have completely eliminated the need for hunger, physical labor or even movement. We have refined and processed our foods to the point where they are poisonous. We regularly overconsume all forms of energy in complete disproportion to our expenditure. We have assigned the task of physical labor to the few underpaid manual labourers left in the world and to machines. We have created special facilities just to put movement back into our lives. We regularly engage in periods of starvation and semi-starvation in an effort to thwart the effects of overconsumption/underexpenditure disease.
Over the past five decades, we have become fat, lazy, overfed and sedentary. Obesity is slowly and tragically becoming the norm, and if this trend continues, eventually the quality of life will be irreversibly altered. In an effort to capitalize on the obesity tragedy, hundreds of companies have sprung up selling all kinds of gadgets, powders, pills, diets, drinks, books, exercise plans, exercise videos and practically anything else that they could pawn off on an unsuspecting and desperate general public.
Today, consumers are definitely more knowledgeable and wary, but still just as desperate. Lately, there has been a lot of hype in the media about low-carbohydrate diets. Recently, they have become the norm in the world of popular diet trends. Atkins, The Zone, The Southbeach Diet, The Metabolic Diet and countless others have made a fortune selling low carbohydrate dietary protocols. It seems like everyone you talk to is either on or has at least tried one or more of the many existing low-carbohydrate dietary protocols.
Regardless of its popularity, carbohydrate restriction has several drawbacks which can limit its usefulness and effectiveness, especially in the long-term. Despite warnings from the medical community, people are still turning to low-carbohydrate dietary protocols as a means of losing weight, and they are losing weight. The question is why are they losing weight. The first and foremost reason is that, irrespective of where the energy comes from (carbohydrates, fats and proteins), there is a sudden drop in energy intake. When people begin any diet, they are usually coming from a period of overconsumption, and the relative amount of energy that they consume on their diet is often much less than what they were previously consuming. This can account for at least some of the weight-loss affect associated with low-carbohydrate diets. Also, when you begin any type of calorie-restricting diet, there is always an initial loss of body water which contributes greatly to overall weight-loss in the first couple of weeks.
In dietary protocols where carbohydrates are restricted, there is an even greater loss of water, because carbohydrates are stored with a large amount of water. As the diet progresses and glycogen stores become depleted, the water that was stored with it is lost. This can account for up to 50% of the weight that an individual may lose in the first two weeks. Also, low-carbohydrate protocols lead to muscle wasting, which also contributes to overall weight-loss. The proportion of fat that is actually lost, especially in the beginning stages of carbohydrate restriction, may be much lower than a scale may show. Ultimately, the real question is does dietary carbohydrate restriction actually lead to greater fat loss?
Overconsumption of carbohydrates does lead to increased fat storage. Carbohydrates are stored in the liver and muscles in the form of the complex carbohydrate Glycogen. Once the capacity for glycogen storage has been reached, any excess incoming glucose will be converted into stored fat. Obviously people who overconsume carbohydrates will benefit from reducing them.
Exercise, especially resistance exercise, can greatly increase an individual's capacity to store carbohydrates. This can be extremely useful in reducing the potential for storage of excess carbohydrate as body fat. Before beginning any diet which prescribes the restriction of any one of the macronutrients (carbohydrates, proteins or fats), an individual should be fully aware of all the effects of such a protocol, both positive and negative. There is a great deal of individual variation in response to any given dietary protocol. If we consider the the nearly infinite number of possible metabolic scenarios, it becomes clear that there can not be only one way that works best, or even one way that works best for us forever. The exercise and diet routine that initially allows us to lose weight, ultimately will lose its ability to stimulate change. Regular variation of diet and exercise protocols is necessary to stimulate further weight loss. An individual must be willing to experiment and make notes of their progress in response to different protocols.
Dietary and exercise tracking offers a tremendous opportunity for an individual to customize their own protocols. There are several schools of thought regarding how to apply the low-carbohydrate principle. On one extreme, there are the low-carbohydrate/high fat/high protein proponents. These include the Harvey-Banting Diet by William Banting (1863), the Stone Age Diet by Dr Richard Mackarness, MB, BS, DPM (1958), the Dr Atkins' Diet Revolution by Robert C Atkins, M.D.(1972), and the Go-Diet by Dr. Jack Goldberg (1999). They claim that by replacing carbohydrate calories with fat calories, that somehow the body will become 'fat-adapted' and will then magically surrender its fat stores.
As you will discover, this may not be an entirely accurate way of describing how the body responds to low carbohydrate/high fat dietary protocols. On the other end of the spectrum, there are the low-carbohyadrate/low fat/high protein proponents. These include the Protein Power Lifeplan by Michael R. Eades, M.D., and Mary Dan Eades, M.D. (1995) and the New High Protein Diet by Charles Clark (2002). They claim that in order to benefit from the fat-loss effects of carbohydrate restriction, while at the same time minimizing the possible health risks associated with high fat dietary protocols, replacing calories from carbohydrates and fats with mostly protein is the best alternative.
Despite the intentions of high protein proponents to reduce the possible health risks, high protein protocols also present certain risks. There are also the many varieties of macronutrient ratio diets, that prescribe specific ratios of carbohydrates, fats and proteins in order to maximize fat-loss and minimize health risks. These include Enter the Zone by Barry Sears Ph.D. (1996) and the Metabolic Diet by Dr. Mauro Di Pasquale (2000). Then there are the GI (glycemic index) protocols which restrict carbohydrate intake to those which are low on the glycemic index or 'smart carbs'. These include the Southbeach Diet by Dr. Arthur Agatston (2003), the Insulin Resistance Diet by Cheryle R. Hart. M.D. and Mary kay Grossman, R.D. (2001), and the Type 2 Diabetes Diet Book : The Insulin Control Diet - Your Fat Can Make You Thin by Calvin Ezran, M.D. with Kristin L. Caron, M.A. (2000). These protocols claim that by reducing the body's exposure to high GI carbohydrates, insulin levels will decrease and so will its fattening effects.
This may in fact be a very useful tool for some people, but not for everyone. With so many possibilities, it is hard for people to decide what works and what doesn't. It is important to remember that every individual will respond differently to a variety of dietary protocols. In part 2 of this series, I will discuss some of the concerns that medical community has regarding low carbohydrate protocols, and I will discuss some of the metabolic rational behind them.
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Sam Torontour, B.Sc., C.S.C.S. is an experienced personal trainer and certified strength and conditioning specialist with over 15 years experience as a fitness professional. With a Bachelor of Science degree in Exercise Science and a minor in Biology from Concordia University, he possesses a thorough scientific understanding of the workings of the human body, nutrition and exercise.
He is certified by the National Strength and Conditioning Association (NSCA) as a Certified Strength and Conditioning Specialist (CSCS) and has expertise in a wide variety of areas. His specialties include physique transformation, athletic preparation, muscle balance and posture, flexibility, nutrition and supplementation. He is also an instructor of Muay Thai (an ancient martial art developed in Thailand). He has worked with males and females of all ages and from all walks of life, including students, older adults, teens and professionals. He is presently working at Gym L’Apogée on St. Laurent Boulevard in Montreal, and also works with clients at their homes.