In the last couple of decades, dieting trends have astronomically increased. The average dieter has trained his or her ears and eyes to react to the word ‘fat’. Low fat, reduced fat, fat free- these are all words that until recently have set alarms off ringing in the typical dieter’s head. Recently, new vocabulary, such as ketogenic, ketosis, and low carbohydrate have stepped into the dieter’s world and questioned, or rather challenged, the ‘fat’ free method of dieting. So, after you have devoured the entire box of ‘fat’ free cookies perhaps you will ask yourself....WHAT ABOUT THE CARBOHYDRATES???
Ketogenics...Low-Carbohydrate...Ketosis...what does
all this mean?
Ketogenic diets, often called low-carbohydrate
(low carb is slang), seem to be the latest diet trend. There are
many different forms, all varying in different degrees. Ketogenic
diets focus primarily on the limited intake of carbohydrates in the food
pyramid. In order to clearly understand ketogenic diets, one must
start with the basics-what are ketones and where are ketones found and
produced???
Ketose is any sugar that contains a ketone group. Ketone bodies are the normal physiological defenses in starvation. Ketone bodies are normal products of lipid and pyruvate and found within the liver. When an impaired or absent carbohydrate intake occurs, the body increases its production of ketone bodies and metabolizes them as an energy source. Ketogenesis, which is the production of ketone bodies occurs in ketogenic diets, resulting in a ketotic state( Miller-Keane 1997). So, “when the requirement for glucose cannot be met by other means, the tissues of the body rely increasingly on ketone bodies as an energy source” (Volpe 1983).
what
are ketogenic diets
what
is the purpose of a ketogenic diet
Ketogenic diets claim to help a variety of conditions
ranging from epileptic seizures to obesity to high blood pressure.
The concept of ketogenic diets is pretty basic. The notion behind
ketogenics is designed to minimize carbohydrate and protein intake and
maximize fat intake. “The diet is high in fat, and low in carbohydrate
and protein, which results in ketosis” (http://www.netphonic.com/demo/stanford/faxdos/ketoprotoc.html).
This idea is that once carbohydrate intake is limited then positive effects
will result. Ideally, these positive effects will help alleviate
the health concern at hand. Ketogenic diets seem to appeal the most
to those interested in weight loss and epileptic seizures.
Ketogentic
diets for the purpose of weight loss
Ketogenic diets have recently inched into the dieter’s
spotlight as a new trend guaranteed to facilitate weight loss. The
idea behind this is that as one limits his or her carbohydrate intake,
cravings for those carbohydrates will diminish, and thus, the dieter will
consume fewer calories. As the dieter’s caloric intake lowers weight
loss will occur. This diet is designed to target those of us who
are “frequently depicted as being driven by ‘carbohydrate cravings’” (Fairburn
1993). Those who suffer from ‘carbohydrate cravings’ crave food high
in carbohydrates, such as pasta, bread, potatoes, sugar, etc. at a rate
that is sometimes believed to be excessive. But, if these foods are
eliminated, the result will be a consumption of fewer calories, essentially,
tricking one’s mind into limiting the calories by limiting the food allowed
according to the diet. There are several of these diet plans available
and almost all of them require purchasing books and/or products in the
process. The majority of these diets claim to increase fat burning
and stabilize blood sugar levels. One such plan, “The Atkins Diet”
by Dr. Richard Atkins, claims if one “limits the body’s carbohydrate intake,
the body must turn to its own fat storage for the energy it needs to function
throughout the day” (http://www.atkinscenter.com/diet101.html).
It goes on further to claim that “Atkins Dieters rarely eat when they’re
not really hungry, have increased mental clarity throughout the day, maintain
consistent energy levels and even tend to need less sleep” (http://www.atkinscenter.com/diet101.html).
Other diet plans that are similar to the notion of ketogenic diets
are:
-Dr. Barry Sears, “Entering the Zone”
-Drs. Mary and Michael Eades, “Protein Power”
-Grant Magnuson, “Stone and Spear”
-Ray Audette, “NeanderThin”
These diets, along with many others, are easily accessible
and can be located through
http://www.syndicomm.com/lowcarb.html
Ketogenic
diets for the purpose of controlling epileptic seizures
Ketogenic diets are also believed to be beneficial in
controlling epileptic seizures, specifically in children. The Ketogenic
Diet claims to create a “ketotic state which exerts an antiepileptic effect”
(http://www.netphonic.com/demo/stanford/faxdocs/ketoprotoc.html).
For this purpose, a ketogenic ratio of 4:1 based on FAT:PROTEIN plus CARBOHYDRATES
is established. This notion behind this is that the proper ratio
of fat to protein plus carbohydrates will result in a dramatic decrease
in seizures. The magic number, if you will, is calculated precisely
and then divided into allotments of three or four meals. These diets,
similar to those intended for weight loss are “high in fat, and low in
carbohydrates and protein, which result in ketosis...fluids are also limited”
(http://www-leland.stanford.edu/group/ketodiet/FAQ..html).
Usually the ketogenic diet is used as a method secondary to anti-seizure
medications. Children are often hospitalized in order to initiate
the diet safely. They are given a keto team, which involves parents,
doctors, dietitians, and pharmacists. For a partial list of centers
and programs that are offered in the ketogenic diet contact:
http://www-leland.stanford.edu/group/ketodiet/
Are
ketogenic diets effective
The Web harbors endless amounts of information on ketogenic
diets used for both weight loss and epileptic seizure control. A
great deal of information is testimonials by dieters and parents of epileptic
children claiming the success they have experienced with ketogenic diets.
Dieter testimonials include “a feeling of well being and comfort, an increase
in energy level, and large amounts of weight loss” (http://www.leanforlife.com/ketosis.htm).
Dieters claim this is “the most incredible weight-loss breakthrough ever”
and argue that this diet allows one to enjoy “bacon,eggs, cheese, steaks,
sausage, cream, mayonnaise, butter, and much more” (http://members.aol.com/regul8in/Ketosis.htm).
Some diets state a specific amount of weight loss per week, such as the
Ketosis Diet by Maymac Enterprises in which you are guaranteed to loose
“seven to ten pounds per week, eating all the rich delicious foods you
want”. This diet goes on to claim that “on this diet you will only
lose fat, not valuable muscle tissue” (http://members.aol.com/regula8in/ketosis.htm)!
Additionally, the Web contains an influx of information
on ketogenic diets used to control seizures. Much of this information
is of similar style to weight loss diet plan. Testimonials from parents
claiming ketogenic diet success fill page after page, while support group
sign ups and visitor registrations also appear. Web sites solely
established for successful testimonials exist as well. Like the ketogenic
diets designed for weight loss, the web also contains various documents
on diets used to treat seizures by specialists from health centers.
These papers seem to be more scientifically based, thus more believable.
However, a fancy name and fluffy terms do not offer definite proof.
Sights such as the Packard’s Children’s Hospital at Stanford University
Medical Center provide tremendous amounts of information; however, are
not scientifically cited. They can be visited at:
http://www-leland.stanford.edu/group/ketodiet/
Scientific
facts about ketogenic diets and weight loss
As opposed to the advertising techniques and sale pitches
that seem to overwhelm one while ‘surfing the Web’ about ketogenic diets,
reports of well-designed, well-researched, empirically sound, scientific
literature regarding ketogenic diets have been published in many valid
medical journals. The conclusions support most of the claims on the
Web for both weight loss and seizure control; however, these studies focus
more on the long-term effects, rather then short-term, as well as health
concerns and additional skepticism. Nevertheless, the research
does indeed scientifically challenge some of the more extreme claims.
According to the experts, diets that limit carbohydrate
intake do result in weight loss. “The carbohydrate content of the
reducing diet may play an important role in the metabolic changes that
occur during weight reduction” (Racette 1995). Most scientific research
in this field examines weight loss in terms of low carbohydrate diets verses
low fat diets. Reports state that weight loss is more rapid when
the carbohydrate intake is low as opposed to the fat intake. “Diet composition
influenced total weight loss, with subjects on the low carbohydrate diet
losing greater amounts of weight than those on the low fat diet” (Racette
1995). However, research also indicates that “ketogenic diets are
very inconsistent” (Wing 1995). Laboratory studies further state
that while ketogenic diets result in weight loss, it is temporary if normal
eating habits are resumed and the diet is the only means of weight reduction.
In order to achieve optimal, long term weight loss, as well as ideal body
health, a regiment of healthy dieting must be maintained as a lifestyle
along with a regular amount of exercise (Racette 1995).
Scientific
facts about ketogenic diets and seizure control
Ketogenic diets were initially researched in the 1920s
as a treatment option for those with intractable epilepsy. As a result
of new age medications the diet’s popularity decreased significantly; however,
has recently surfaced again as a successful therapy. The majority
of the research in this field has been centered around children.
Research states that “children who respond to the diet usually become more
alert and many are able to gain or regain developmental milestones” (Fiechtner
1995). Empirically sound evidence states that “starvation exerts
an anticonvulsive effect. It is assumed that ketones, generated by
fasting or with a ketogenic diet, contribute to this therapeutic effect”
(Lamers 1995). Ketogenic diets used in an attempt to control seizures
are usually accompanied with medications as well. Research indicates
that the slightest deviation from the diet can cause the ketosis to drop,
and seizures to resume. Many of the uncounted carbohydrates are supplied
in the form of oral liquid medications. As a result, research has
been conducted in an attempt to reduce the occurrence of children regaining
seizures despite following the strict diet (Feldstein 1996). Within
these studies it has been determined that “tablet and capsule formulations
usually contain much lower carbohydrate amounts than liquid formulations
and are preferred when possible” (Feldstein 1996). Research further
supports much of what the Web claims in that in order for seizures
to decrease a 4:1 ketogenic ratio of FAT:PROTEIN plus CARBOHYDRATE must
be maintained at every meal. It is also essential to monitor not
only medication components, but also that of toothpaste, mouthwash, gum,
etc. (Lamers 1995). Studies also indicate that although products
claim to be sugar-free, they can contain sorbitol which contains significant
quantities of other carbohydrates. (Feldstein 1996).
What
are the effects of ketogenic diets
What
are the unknowns
As previously stated, the main effect of ketogenic diets
is the body state of ketosis. Ketosis is “characterized by a build
up of chemicals known as ketones, which are produced by the body as a by-product
of combusting fat” (Leung 1995). This can lead both the dieter and
children with epileptic seizures to feel tired and lethargic. More
specific to children with epilepsy, symptoms can include “nausea, weakness,
increase in sweating, and dizziness” (http://www.netphonic.com/demo/stanford/faxdocs/ketoprotoc.html).
If this occurs the child should be given a small, specified amount, like
15-30 cc of orange juice, in an attempt to prevent ketosis. Additional
side effects include gas, constipation, and specific breath odor. Excessive
ketosis can result in crankiness and irritability as well. As the
ketotic states are eliminated by the intake of carbohydrates the dieters
report and research indicates that the positive weight loss diminishes,
and inevitably weight gain results (Wing 1995). Furthermore, unknowns
regarding effects of ketogenic diets continue to be researched. Mood and
cognitive performance were thought to be affected by ketosis; however,
studies such as one done by H. Lloyd conclude that further research must
be completed in order to determine such unknowns.
Conclusions
As a dieter, yes, a strict ketogenic diet, limiting
carbohydrates and protein, will result in weight loss. However, this
weight loss has been proven to be short term and once normal eating habits
reappear, so does the weight. Researchers continue to study the effects,
both positive and negative of ketogenic diets. In terms of weight
loss, ideal maintenance will result from a diet of moderation, lifestyle
changes, and regular exercise. The ketogenic diets used for seizure
control recommend children to be released from the diet after a maximum
of two years. While ketogenic diets have indicated the occurrence
of fewer seizures, medications also warrant positive results. As
medical breakthroughs and new diet fads continue to surface, one must be
wary and research thoroughly before taking on unhealthy risks.
Bibliography
Fairburn, Christopher G. and Wilson, G. Terence.
Binge Eating. The Guilford Press, New York, 1993.
Feldstein, Thomas J. "Carbohydrate and alcohol content of 200 oral liquid medications for use in patients receiving ketogenic diets". Pediatrics. 97(4): 506-11, April 1996.
Fiechtner, Helen. "Ketogenic diet for seizure control". South Dakota Journal of Medicine. 48(10): 353, October 1995.
http://www.atkinscenter.com/diet101.html
http://www-leland.stanford.edu/group/ketodiet/
http://www-leland.stanford.edu/group/ketodiet/FAQ.html
http://www.leanforlife.com/ketosis.htm
http://members.aol.com/regula8in/ketosis.htm
http://www.netphonic.com/demo/stanford/faxdos/ketoprotoc.html
http://www.syndicomm.com/lowcarb.htm
Lamers, K.J., F. Gabreels, W. Renier, R. Wevers, and W. Doesburg. "Fasting studies in cererbrospinal fluid and blood in children with epilepsy of unknown origin". Epilepsy Research. 21(1): 59-63, May 1995.
Leung, L.H. "Pantothetic acid as a weight reducing agent: fasting without hunger, weakness and ketosis". Medical Hypothesis. 44(5):403-5 May, 1995.
Lloyd, Helen, M. Green, and P. Rogers. "Mood and cognitive performance effects of isocaloric lunches differing in fat and carbohydrate content". Physiology-and-Behavior. 56(1): 51-57, July 1994.
Miller-Keane. Encyclopedia & Dictionary of Medicine, Nursing, & Allied Health. W.B. Saunders Company, Philadelphia, 1997.
Racette, S., et al. "Effects of aerobic exercise and dietary carbohydrates on energy expenditure and body composition during weight reduction in obese women". American Journal of Clinical Nutrition. 61(3): 486-94, March 1995.
Stephen, A.M., G. Seiber, Y. Gerster, and D. Morgan. "Intake of carbohydrate and its components-- international comparisons, trends over time, and effects of changing to low-fat diets". American Journal of Clinical Nutrition. 62(4): 851S-867S, October 1995.
Vazquez, Jorje, and S. Adibi. "Protein sparing during treatment of obesity: ketogenic versus nonketogenic very low calorie diet". Metabolism. 41(4): 406-414, April 1994.
Volpe, Peter E. Biology and Human Concerns. Wm. C. Brown Publishers, Iowa, 1993.
Wing, R.R., J. Vazquez and C. Ryan. "Cognitive effects
of ketogenic weight reducing diets". International Journal of Obesity
and Related Metabolic Disorders. 19(11): 811-16, November 1995.
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