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In addition to the negative social drawbacks associated with being obese, there are several physical and health risks. Because of this, the issue of obesity has become a widely discussed topic in the United States, especially during the past twenty years. Experts have estimated that somewhere between one in every four and one in every three Americans are obese, and over 55% of Americans over the age of twenty could be classified as being overweight. This number continues to rise.
Mass Index (BMI) is a scale that uses height and weight to determine body fat.
This figure can then be compared to averages to determine if one is at risk
for particular health risks. A BMI over 25 is considered overweight, and over
30 is obese. The risk factors that are associated with obesity include
diabetes, coronary artery disease, stroke, gallbladder disease, sleep apneas,
and even some types of cancers. With all of these health concerns, why is
obesity an increasing problem?
to the Colorado Health Net the cost of treating obesity and health-related
concerns amounts to about $68 billion per year, not including the $30 billion
per year spent on additional weight loss diet programs and special foods. http://www.coloradohealthnet.org./.
are many different viewpoints as to ways to attack the growing problem of
obesity. Experts claim to have found an obesity gene, which explains that
those who are obese have little control over it http://dmi-www.mc.duke.edu/dfc/gene.html
. When the gene is altered in mice, the amount of fat stored in the body
varies. Because of the newness of the research and the obvious costs
associated with this, it is not a likely procedure.
though genetic manipulation as a treatment for obesity is years away from
practical application, science has attempted to tackle the problem of weight
loss in several different ways. One such method uses insulin manipulative
drugs in an effort to stabilize blood sugar that would otherwise aid in the
storage of fat. Another method uses beta- receptor stimulation to increase
thermogenesis. Additionally, appetite is controlled through the use of
selective seretonin reuptake inhibitors (SSRI’s) and other appetite
diets and exercise seem to be the most widely practiced method of weight loss,
but with obesity being such an enormous health risk, many are seeking
additional treatments. One researcher with the Mayo Clinic,http://mayohealth.org/,
Maria L. Collazo- Clavell, M.D., claims that there is evidence that a loss of
5- 10% of body weight greatly reduces the risks of many of the conditions
associated with obesity. She claims that the problem is that people have
difficulty achieving and especially sustaining the weight loss.
is indeed a large part of the battle, but in cases where a patients is too ill
or too overweight to exercise, additional programs must be instilled. This is
when other treatments must be used.
company Roche has developed a new drug called Xenical (orlistat). Unlike many
other diet drugs, Xenical is different from other drugs, like the ones
discussed above, because instead of altering brain chemistry to suppress
appetite or increasing the amount of energy expended, it works by inhibiting
the action of an enzyme found directly in the gastrointestinal tract.
first submitted an application for Xenical to the FDA in 1996. It was
recommended for approval in 1997, but then put on hold because of data that
showed cases of breast cancer, which occurred during the clinical trials. It
was later determined that these cases were due only to chance and in April of
1999, the FDA approved Xenical for use by doctors for obese patients, those
with a BMI greater than 27.
to the Xenical website, http://www.xenical.com/howshould.asp,
the recommended dose of Xenical is one 120-mg capsule taken with liquid during
a meal or within one hour of eating. It should be taken each time you eat a
meal that contains fat. Although Xenical prevents the breakdown and absorption
of fat, each meal should be well balanced and should not contain more than 30%
of the calories from fat. If a meal is skipped or if it contains no fat
Xenical should not be taken. It has been shown that doses above 120-mg, three
times a day does not contribute to additional weight loss.
the patients consumes a balanced meal and uses the drug as prescribed, some of
the side effects experienced while taking Xenical may be reduced.
So how does Xenical work? http://www.xenical.com/howxenicalworks.asp
Calories that are not used by your body for energy are stored for later
usage. The more you eat, the more you store, unless, you increase your energy
expenditure by adding extra physical activities to your day.
When food enters your stomach, a series of enzymes are used to break
down each element of your meal. One particular type of enzyme is called
lipases. Lipases are used to digest and break down fats. When Xenical is taken
during a meal, it attaches itself to the lipases preventing them from breaking
down the fats. If Xenical is attached to the lipase enzymes, they are unable
to perform properly. The result is that all of the undigested fat cannot be
absorbed into your body and thus it is eliminated through your bowels.
Approximately one third of the fat that is consumed will be expelled in this
The process of undigested fat leaving the body is one major drawback to
those taking Xenical. The side effects include oily rectal seepage, gas with
discharge, oily bowel movements and frequent bowel movements. If more fat is
consumed than is recommended, the symptoms worsen. This is another way in
which Xenical works. If the symptoms worsen when extra fat is consumed, the
person may become conditioned to watch out for the amount of fat that is
consumed while taking the medication.
In addition to these side effects, the expulsion of fats from the body may reduce the absorption by the body of fat- soluble vitamins (A,D,E, and K) and beta- carotene. The FDA recommends that people who use Xenical should also take a supplement of these vitamins two hours before or after taking Xenical.
According to http://www.xenical.com/,
After one year of treatment, a diet aided by Xenical was more successful than
diet alone in reducing weight. Weight loss was gradual in clinical trials, but
the average user lost 13.4 pounds over the course of a year. Those only on a
reduced calorie diet lost and average of 5.8 pounds. Twice as many Xenical
users lost over 10% of their body weight than those who only dieted. In these
cases, the average weight loss was 31 pounds, and ranged between 16 and 74
Additionally, it should be noted that the benefits of taking Xenical
extend far beyond the physical changes. Dr. Collazo- Clavell announced that
studies have demonstrated that Xenical also cause small, yet statistically
significant decreases in cholesterol, insulin levels and blood pressure. This
ensures that the benefits may be far reaching. Because of this, Xenical is
also used for those who have high blood pressure, high cholesterol, or
Although the information handed down from Roche Company and the FDA
seems to fully support this drug for use as a method of weight loss, many
others have conducted their own research on Xenical to make sure.
Hauptman, et al., conducted an experiment in a primary care setting to
see how his results compared to those published. He conducted a two- year,
single- blind, placebo- controlled study with 796 obese patients. 212 received
the placebo, 213 received 60-mg Xenical three times per day, and 210 received
120-mg Xenical three times per day. The weights of the participants were
recorded at 52 weeks and at 104 weeks.
At the end of the study, the dropout rates were extremely high. They
were 57.1%, 44.1%, and 46.2% respectively. As reported, the average weight
losses per group were as follows: 9.37 pounds at 52 weeks and 3.39 pounds at
104 weeks in the placebo group, 17.42 lbs at 52 weeks and 10.08 lbs at 104
weeks in the 60-mg group, and 19.32 lbs at 52 weeks and 11.35 lbs at 104 weeks
in the 120-mg group. The adverse side effects that were reported in 20-25% of
the patients were fecal urgency, oily spotting, fatty stools, and flatulence.
The weight loss did cause the total cholesterol level to decrease, but it was
concluded that the decrease in the LDL cholesterol levels, which were about
the same in both Xenical groups, was more likely to be dependent upon another
effect of Xenical other than it’s weight loss properties.
In conclusion, the researchers agreed that it would be unlikely that
the Xenical would meet the treatment expectations of the patients and
In Stockholm, Sweden, Professor Stephan Rossner decided that he would
look into the long term benefits of Xenical on weight- loss and obesity
related risk factors. He and his researchers performed a two- year randomized,
double- blind, placebo- controlled study on this drug. Obese patients were
placed randomly into either the Xenical group or the placebo group. The first
year the participants ate a hypocaloric diet and the second year they ate a
weight maintenance diet. This was to test for regain of weight. Changes in
body weight, fat profiles, glycemic control, blood pressure, and overall
quality of life were monitored.
results suggest that patients in the Xenical group lost significantly more
weight and experienced less weight gain, than the control group. They also
improved in the group of obesity related risk factors and overall quality of
interactions between Xenical and other drugs have also been studied. In
Switzerland, Hartmann, et al., looked at the interactions between Xenical and
the ovulation- suppressing action of oral contraceptives. After measuring the
levels of hormones active in a menstrual cycle, he determined that Xenical did
not have any influence or interaction with oral contracepives.
researchers in Switzerland looked at interaction between Xenical and ethanol
in volunteers. They found that the ingestion of ‘social’ amounts of
ethanol did not alter the effects of Xenical.
different groups of people have looked into the effects of the new dietary
drug Xenical. And from all sides it seems as if there is enough evidence to
safely recommend this drug to obese patients who are looking for a way to lose
weight. The main drawback of this drug is the gastrointestinal side effects,
which should not be that harmful. As long as the prescription is followed and
as long as the extra vitamins are taken, it seems as if this drug could be a
breakthrough in helping to combat the increasing problems with obesity… as
long as you and your friends can ignore the side effects.
D., Guzelhan, C., Zuiderwijk, P., Odink, J. Lack of interaction between
orlistat and oral contraceptives. TNO Nutrition and Food Research. 1996; 50
J., et al. Orlistat in the long- term treatment of obesity in primary care
settings. Arch Family Med. 2000; 9: 160-7.
A.T., Zhi, J., Zelasko, R., Hartmann, D., Guzelhan, C., Guericiolini, R.,
Odink, J. Pharmacokinetics and disposition: The interaction of the lipase
inhibitor orlistat with ethanol in healthy volunteers. TNO Nutrition and Food
Research. 1998; 54 (9-10):773-7.
S., Sjostrom, L., Noack, R., Meinders, A., Noseda, G. Weight loss, weight
maintenance, and improved cardiovascular risk factors after two years
treatment with orlistat for obesity. Obesity Research. 2000; 8: 49-61.
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