We've all seen the hype surrounding the Atkins diet. It's everywhere you look - in magazines, on supermarket shelves, in television ads, and possibly even in your healthcare provider's office. It's so popular that maybe you've even tried it or at least been thinking of trying it.
So how exactly does a low-carb, high-fat, high-protein diet work? And does eating all the bacon, steak, and eggs that you could possibly dream of really bode well for your overall health both in the short term and in the long run? Let's find out as we take a peek inside these low-carb diets and really get to the bottom of the science behind the bacon grease.
How Your Body Obtains Energy
We all need energy to keep living. Without energy we wouldn't be able to feed ourselves, bathe ourselves, or get dressed in the morning much less go to work everyday. So where does this energy come from?
Our bodies rely heavily on glucose and glycogen as its main sources of energy. The brain almost exclusively relies on glucose as it's main fuel source  while our muscles rely on glucose and glycogen for its fuel sources especially the more we move around and use them . Glucose is acquired when the carbohydrates you eat are broken down into simple sugars that can readily be used to make energy inside your cells. So when you're studying for that math test, critically thinking about a project at work, or walking to your car glucose is what your cells look to first to help you get the job done.
Glycogen, on the other hand, is a stored form of several glucose molecules all packed together . You can picture what this would look like by envisioning a wadded up ball of individual pieces of scotch tape all stuck together. These little balls of glycogen are mostly stored in the liver and to a lesser extent in muscle cells, red blood cells, brain cells, etc. and serve as a secondary source of energy. When your blood sugar drops your liver is then triggered to break down glycogen to supply energy to your cells so you can keep on doing whatever it is that you're doing.
But what happens if you run a marathon or partake in really intense forms of exercise? How about going on a fast for several days or experiencing a state of starvation? And what about going on a low-carb diet like the Atkins diet? Don't these all deplete your glucose and glycogen stores? They certainly do but human beings have lived through all of these scenarios and are still able to get their energy from somewhere. But where is it coming from? The answer to this lies in the following key processes:
- Gluconeogenesis - The generation of glucose from non-carbohydrate precursors such as proteins and other substances.
- Ketosis - A metabolic state in the body in which fats are broken down into fatty acids and ketone bodies. Some of the resulting ketone bodies are then used to produce energy.
When individuals go on a low-carb ketogenic diet their metabolism changes to acquire their energy needs by using dietary fat and protein along with fat stores already in the body instead of glucose obtained from carbohydrates. From the body's viewpoint this resembles starvation  and after about 3 days the brain starts to utilize ketone bodies from the breakdown of fat as its source of fuel instead of glucose .
In the meantime, vital cells and other areas of the body (red blood cells, retina and lens of the eye, and innermost portions of the kidney) are glucose-dependent and get their energy needs through the breakdown of small amounts of glycogen left in the body or through gluconeogenesis . In effect, your body is bypassing its first choice for making energy because its being forced to do so and instead opting for the second and third alternatives which are methods typically left for a starvation mode or other extreme short term demands on the body.
Health Risks Involved With Low-Carb Ketogenic Diets
Low-carb ketogenic diets (LCKD) do in fact lead to weight loss at least in the short term but not because of the lack of carbohydrates consumed. The weight loss is typically due to a decrease in the total number of calories consumed on a daily basis . A reduction in caloric intake is also associated with decreased appetites in these same individuals . Proponents of LCKD also point to evidence that going low carb reduces triglycerides and increases HDL (good cholesterol) levels .
This is all good stuff right? It would seem so on the surface but when you gain an understanding of how individual foods affect the human body and couple that with the fact that there is a lack of long term data to support the health benefits of LCKD then you will understand why you should skip this approach all together if you're trying to lose weight and feel great. LCKD actually promotes eating foods such as meats and dairy products that are high in saturated fats and cholesterol which have been shown to increase your risk of heart disease and strokes. In addition to this, LCKD also results in a lack of fiber in one's diet as well as a deficiency in disease fighting phytochemicals and antioxidants only found in plant foods. Hence, you have an increased risk of many different types of cancers by taking this approach.
Heart Disease Risk
The fact that LCKD has been shown to decrease cardiovascular risk factors such as reducing triglycerides and increasing HDL in the short term does not mean it actually reduces cardiovascular events such as angina, heart attacks, and strokes. In a meta-analysis on LCKD vs. low fat diets it was found that LDL (bad cholesterol) and total cholesterol changed more favorably in people put on a low-fat diet compared with those on a LCKD .
Total cholesterol and LDL levels are much better predictors of whether or not an individual would experience cardiovascular events than HDL and triglycerides are. Dr. Caldwell Esselstyn (Director of the Cardiovascular Disease Prevention and Reversal Program at the Cleveland Clinic) has published a study following patients over a 12 year period on a low-fat, plant-based diet. His patients have experienced remarkable results. In the 8 years prior to his study his patients had a total of 49 coronary events. All the patients who maintained the low-fat, plant-based diet had a total of ZERO coronary events during the 12 years on the study and they all experienced a reversal in the damage done to their hearts . Dr. Esselstyn's patients had total cholesterol values in the range of 112-162 mg/dl and LDL levels of 48-102 mg/dl. In contrast, the meta-analysis mentioned above reported the following cholesterol levels after a six month period for individuals following a LCKD - total cholesterol 182-244 mg/dl and LDL 112-159 mg/dl . No data was available beyond 6 months in regards to cholesterol levels in these individuals. As you can see these levels were much higher than those seen in Dr. Esselstyn's patients.
In May of 2004 the dangers of the Atkins diet on heart health came to light when Jody Gorran, a Florida business executive, sued Atkins Nutritional Inc. and Atkins's estate for negligent misrepresentation, product liability, and deceptive and unfair trade practices. In the winter of 2000 Mr. Gorran had an excellent report card when it came to his heart health. His cholesterol levels were as follows - total cholesterol=146 mg/dl, HDL=53 mg/dl, LDL=85 mg/dl, and triglycerides=42 mg/dl. He also had a CT scan of his heart done with stellar results showing no atherosclerosis and was found to have "very low coronary vascular disease risk". After going on the Atkins diet for 2 1/2 years Mr. Gorran suffered a heart attack and had to have a cardiac cath done. His cholesterol levels had shot up to the following - total cholesterol=209 mg/dl, HDL=53 mg/dl, LDL=127 mg/dl, and triglycerides=144 mg/dl. Mr. Gorran's cardiologist told him to go off the Atkins diet immediately. He did so and after about two months had his blood work done again with the following results - total cholesterol=146 mg/dl, HDL=52 mg/dl, LDL=81 mg/dl, triglycerides=65 mg/dl. Mr. Gorran lost his case againts Atkins and the court ruled that the diet was "not unfair or deceptive" and that the Atkins diet and ideas were protected by the first amendment.
Increased Cancer Risk
LCKD are both high in fat and in protein and consist heavily on the consumption of meat, dairy, and eggs. Consuming these foods has been shown in multiple studies to increase your risk of several different types of cancers. Below is just a handful of studies attesting to this:
- A total of over 478,000 men and women were followed for about 5 years. Colorectal cancer was positively associated with both red and processed meat in study participants .
- One study showed a six-fold increase in lung cancer risk in non-smoking women in those who consumed a diet high in saturated fats .
- An epidemiological study in the British Journal of Nutrition showed an increased risk in colorectal, stomach, and breast cancer from consuming red and processed meats. Consuming animal fats was also associated with an increased risk in colorectal, prostate, and breast cancer .
- A study of 3,892 men over a 15 year period showed an increase risk in prostate cancer due to the consumption of processed meats and dairy products .
- Over 17,600 males were followed for 20 years in one study and men in the highest quartile of meat intake had 3 times the risk of pancreatic cancer mortality than those in the lowest quartile .
As you can see a diet that consists of mostly protein and fat especially when derived from animal sources greatly increases your risk of developing a number of different cancers. This is likely due to the fact that meat, dairy, and eggs contain no fiber or antioxidants both of which are vital when it comes to protecting yourself against cancer.
Other Health Concerns
A higher risk of heart disease and cancer aren't the only things you should be concerned about by low-carb, high-protein diets. LCKD has been shown to increase the amount of calcium lost in the urine leading to a calcium imbalance which increases the risk of bone loss in individuals . This same study showed a two fold increase in uric acid load in the urine which has been linked to a greater risk in kidney stone formation. Another study found that a re-emergence of panic and anxiety symptoms was seen in people while on a high protein, low carbohydrate diet .
But probably the most convincing reason you would never want to go on a LCKD was published in 2010 in the Annals of Internal Medicine. In the reported study a total of approximately 130,000 men and women without heart disease, cancer, or diabetes were followed over a 20-26 year period. Researchers found that consuming a low-carb diet based on animal sources was associated with a higher overall cause of death in both men and women than in those who consumed a vegetable-based low carbohydrate diet .
The low carb craze has swept the nation for many years now and to the dismay of many of its proponents it simply fails to provide legitimate long term solutions to both weight loss and overall health. While short term weight loss is achieved along with some questionable reduction in cardiovascular risk factors it has been proven many times over that the best way to achieve long term weight loss and optimal health is by adopting a plant-based diet.
If you know somebody who is thinking about going on a LCKD then please share this article with them and inform them of the dangers involved with such a diet. We are all allowed to do what we feel is best for ourselves when it comes to the foods we eat. With the proper knowledge on how foods affect your body you have an enormous amount of control over your own destiny. If you need more in depth information on nutrition and overall health feel free to visit my website as there is a vast amount of material there backed by proven science that will undoubtedly help you achieve the very best out of yourself.
May you prosper in health and happiness!
Dustin Rudolph Pharm.D.
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