Ketogenic diet modifies the risk factors of heart disease in obese patients

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PRELIMINARY REPORT
Ketogenic Diet Modifies the Risk Factors of Heart
Disease in Obese Patients
Hussein M. Dashti, MD, PhD, FICS, FACS, Yousef Y. Bo-Abbas, MD, FRCPC,
Sami K. Asfar, MB ChB, MD, FRCS Ed, FACS,
Thazhumpal C. Mathew, MSc, PhD, FRCPath, Talib Hussein, MB ChB,
Abdulla Behbahani, MB ChB, FRCS, FACSI, PhD, FICS, FACS,
Mousa A. Khoursheed, MB ChB, FRCS, FICS, Hilal M. Al-Sayer, MD, PhD, FICS, FACS,
and Naji S. Al-Zaid, BSc, PhD
From the Department of Surgery, the Department of Medicine, and the Department of
Physiology, Faculty of Medicine, the Department of MLS, Faculty of Allied Health,
Kuwait University, Safat, Kuwait; and the Ministry of Health, Safat, Kuwait
INTRODUCTION
It is generally believed that high-fat diets may lead to the devel-
opment of obesity and several other diseases such as coronary
heart disease, diabetes, and cancer. This view is based on studies
carried out in animals that were given a high-fat diet rich in
polyunsaturated fatty acids. However, various recent epidemio-
logic studies have not explained a specific causal relation between
dietary fat and obesity or obesity-associated diseases.
1
Further, contrary to the common notion, a high intake of
carbohydrates was found to increase the levels of triacylglycerols,
total cholesterol, and low-density lipoprotein (LDL) cholesterol
and decrease the level of high-density lipoprotein (HDL) choles-
terol. Elevated levels of triacylglycerols and low levels of HDL
were associated with hyperinsulinemia. Also, an elevated triacyl-
glycerol level, particularly a high ratio of triacylglycerols to HDL,
is an important predictor of heart attack.
2
Recent studies have quite evidently shown that the ketogenic
diet is a natural therapy for obesity and obesity-associated dis-
eases. However, there are very few studies that have addressed the
long-term influence of a ketogenic diet in modifying various
obesity-associated diseases. Hence, the purpose of this study was
to investigate the long-term effect of a ketogenic diet on the
activation and modification of heart disease risk factors in obese
patients.
MATERIALS AND METHODS
A prospective study was carried out at the Academic Department
of Surgery, Consultation and Training Center, Faculty of Medi-
cine, Kuwait University in 102 (42 male and 60 female) obese
subjects whose body mass index was 37.4  0.7. Mean age was
40.8  1.0 y (58.8% female and 41.2% male). Fasting blood tests
were carried out for all the subjects. Initially all the patients were
subjected to liver and renal function tests. Their glucose and lipid
profiles from fasting blood samples and complete blood count
were performed. Thereafter, their fasting blood samples were
tested for total cholesterol, HDL cholesterol, LDL cholesterol,
triacylglycerol, and blood sugar at 4, 8, and 12 wk.
All 102 subjects received a ketogenic diet consisting of 20 to
30 g of carbohydrate in the form of green vegetables and salad and
Correspondence to: Hussein M. Dashti, Department of Surgery, Faculty of
Medicine, PO Box 24923, 13110 Safat, Kuwait. E-mail: thazhumpal@
kuc01.kuniv.edu.kw
Nutrition 19:901–902, 2003
©Elsevier Inc., 2003. Printed in the United States. All rights reserved.
80 to 100 g of proteins in the form of meat, fish, fowl, eggs,
shellfish, and cheese. Polyunsaturated and monounsaturated fats
were included in the diet. Twelve weeks later, an additional 20 g
of carbohydrate was added to the meal, for a total of 50 g of
carbohydrate. Micronutrients (vitamins and minerals) in the form
of 1 capsule/d were given to each subject.
Statistical differences between various parameters before and
after the administration of the ketogenic diet were analyzed by
paired Student’s t test with Statview 4.02. Weight, body mass
index, and all biochemical parameters are expressed as mean 
standard error.
RESULTS
The changes in the level of the various physical and biochemical
parameters examined are shown in Table I. The level of triacyl-
glycerols showed a significant decrease from before treatment to
12 wk after treatment. The initial level of triacylglycerol was 2.4
mM/L  0.2; at 12 wk the level decreased to 1.2 mM/L  0.1. The
level of total cholesterol decreased from week 1 to week 12. HDL
cholesterol increased significantly, whereas LDL cholesterol de-
creased significantly.
The changes in various other physical and biochemical param-
eters observed before and after the treatment period with the
corresponding P values are given in Table I. There was a signif-
icant reduction in body weight. The level of fasting blood sugar
decreased significantly. In conclusion, consuming a ketogenic diet
for 12 wk is safe, and it favorably modified the risk factors of heart
disease in obese patients.
DISCUSSION
One argument against the consumption of a high-fat diet is that it
causes obesity. Because fat has a caloric density higher than that of
carbohydrate, it is thought that consumption of a high-fat diet will
be accompanied by a higher energy intake. On the contrary, recent
studies including those from our laboratory have confirmed that
the ketogenic diet is a natural therapy for obesity.
In contrast, several current studies have pointed to the fact that
a diet with a high glycemic load is independently associated with
developing cardiovascular diseases, type 2 diabetes, and certain
form of cancers.
1
Another study carried out in the United States
showed that the risk of dietary glycemic load from refined carbo-
hydrates is independent of other known risk factors of coronary
diseases.
3
Now it is quite evident that high-carbohydrate diets
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902 Dashti et al. Nutrition Volume 19, Number 10, 2003
TABLE I.
CHANGES IN THE LEVEL OF VARIOUS PHYSICAL AND
BIOCHEMICAL PARAMETERS AT THE END OF THE
TREATMENT PERIOD (WEEK 12)
Physical and biochemical
parameters Week 1* Week 12* P
Weight (kg)
Body mass index
Cholesterol (mM/L)
HDL (mM/L)
LDL (mM/L)
Triacylglycerols (mM/L)
Glucose (mM/L)
99.2  2.1 85.9  2.6 0.0001
37.4  0.7 33.0  0.8 0.0001
5.4  0.1 4.9  0.1 0.0022
1.2  0.04 1.3  0.04 0.0022
4.0  0.1 3.5  0.1 0.0160
2.4  0.2 1.2  0.01 0.0001
7.0  0.3 5.4  0.1 0.0009
* Data are expressed as mean  standard error.
HDL, high-density lipoprotein cholesterol; LDL, low-density lipoprotein
cholesterol
increase fasting plasma triacylglycerol concentration
4
and decrease
HDL cholesterol concentrations.
5
The data presented in this study showed that a ketogenic diet,
in addition to acting as a natural therapy for weight reduction in
obese patients, significantly decreases the level of triacylglycerols,
total cholesterol, LDL cholesterol, and glucose and increases the
level of HDL. These results, therefore, indicate that the adminis-
tration of a ketogenic diet for a relatively long period is safe and
favorably modifies the risk factors of heart disease in obese
patients.
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