Many non-surgical avenues have been explored to develop
effective treatments for obesity. Unfortunately, in people with
morbid obesity, all of these strategies have been unsuccessful
so far.
Diet and Exercise
The primary approach to treating obese patients is lifestyle
modification: a decrease in calories consumed and an increase
in energy expended. This well-known approach is generally safe
and beneficial for all patients. However, among obese patients,
there’s been no demonstrated long-term maintenance of weight
loss.
The cornerstone of dietary management is
the low calorie diet (LCD), which usually restricts the diet to
800 to 1,500 kcal per day. Average intake includes 250 gm or
more of carbohydrates, 68 gm protein, and 60 gm or less from
fat.
Many commercial diet programs are available, including
Weight Watchers, NutriSystem, Optifast, and Jenny Craig.
Under special circumstances, a very-low-calorie diet (VLCD)
is used providing 250 to 800 kcal/day, but special medical
monitoring is required. VLCD may be useful in special
circumstances for rapid improvement of symptoms of sleep apnea,
hypertension, or hyperglycemia, however clinical studies show
that LCDs are just as effective as VLCDs in producing weight
loss after one year.
A review by VanItallie of the reported results from
low-calorie diets concluded they could produce a weight
reduction of 8 to 10 percent over a six-month period. Long-term
maintenance of weight loss in obese patients has not been
documented in any study.
Many other popular diet programs such as Atkins and the Zone
diets have attempted to reduce weight by changing the types of
foods consumed.
Exercise Programs
An increase in physical activity is recommended for any
weight reduction program, including surgery. Exercise increases
energy expenditure, improves comorbid conditions, combats
depression, and helps maintain weight loss. Generally, up to 30
minutes of moderate-intensity physical activity is recommended
five to six days a week.
In a study of women who had regained lost weight compared to
those who maintained their weight loss, 90 percent of
maintainers engaged in vigorous exercise at least three times
per week for at least 30 minutes, whereas only 34 percent of
the regainers reported this level of activity.
Past Therapies
Multiple attempts were made in past decades to manage morbid
obesity using various drug regimens. The amphetamine-like drugs
did induce weight loss better than placebo in clinical
trials.
However, all studies were short-term and weight gain
occurred after withdrawal of the drugs. Because the risk of
drug abuse was relatively high, long-term utilization was not
recommended.
Minimally invasive mechanical methods to limit dietary
intake, including acupuncture, jaw wiring, and gastric bubbles,
were likewise met with little success.
Current Drug Therapies
Today, drug therapies are usually reserved for patients with
a BMI greater than 30, or greater than 27 in those individuals
with at least one comorbidity related to obesity.
Several appetite suppressants continue to find use in weight
reductions programs. They are usually used only for short-term
results (up to 3 months): phentermine, mazindol, and
diethylpropion. The most commonly prescribed of these is
phentermine, a component of the now-banned phen/fen. When used
alone, phentermine has not been associated with cardiac
valvular abnormalities or primary pulmonary hypertension.
Two new pharmacologic approaches, have had some limited
success in the treatment of obesity: sibutramine and orlistat.
However, in morbidly obese patients, no successful studies have
been reported.
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