Is there finally a solution to the weight-loss puzzle?
IS 5-HTP SUPPOSED TO DO?
The purpose of taking 5-HTP is to reduce carbohydrate cravings, and
thus, diminish food intake, resulting in weight loss.
In addition to promoting weight loss, it has also been linked with
beneficial effects on behaviors such as sleep disturbances, narcolepsy,
depression, migraines, anxiety, bulimia, PMS, compulsive behaviors, substance
abuse, childhood hyperactivity, and hypersexuality.
DOES THIS 5-HTP COME FROM, AND HOW IS IT TAKEN?
5-HTP is obtained by extracting it from the seeds of a legume called
Griffonia simplicifolia, which is found in West Africa.
It is recommended to take anywhere from 50mg to 900mg 5-HTP daily,
depending on the needs of the individual.
It is available in both a capsule or a drink mix.
It should be taken between meals (at least 30 minutes before each meal)
to prevent its interaction with other amino acids and to ensure its
DOES 5-HTP WORK?
A deficiency in the neurotransmitter serotonin (5-HT) has been linked
with a number of behaviors mentioned above.
It has especially been associated with carbohydrate craving because
eating carbohydrates is one way to briefly increase the brain’s level of
5-HT. This occurs because
carbohydrates induce insulin production, and this insulin promotes 5-HT
production. A temporary sense of
well-being and satiety occurs. From
this, it has been concluded that by increasing the brain’s 5-HT levels by
methods other than overeating carbs, these cravings would be avoided, satiety
would be reached earlier, overeating would be avoided, and weight would be
why does 5-HTP have this effect? 5-hydroxy-L-Tryptophan
is a precursor to 5-HT, along with the amino acid tryptophan.
It is thought that by providing the brain with this precursor in the
form of 5-HTP capsules or drink mix, a person’s cells will naturally
increase the production of 5-HT. This
increase in 5-HT induced by the supplements will stop carbohydrate cravings,
increase satiety earlier, and lead to weight loss.
5-HTP instead of the other precursor, tryptophan?
In fact, tryptophan was also once used to alleviate effects of 5-HT
depletion such as depression, anxiety, and sleep disturbances.
However, in 1988, the FDA began restricting the marketing of tryptophan
due to a contaminated batch imported from a Japanese company.
This is what led to the recent focus on 5-HTP, the other
precursor to 5-HT.
ARE THE POTENTIAL DOWNFALLS TO TAKING 5-HTP?
side effects that have been noted to occur during 5-HTP administration include
anxiety, digestive upset, headache, lethargy, muscle pain, gastrointestinal
symptoms, inability to sleep, and nausea.
WHO IS SELLING 5-HTP, AND WHAT CLAIMS ARE THEY MAKING ABOUT IT?
are numerous existing websites that provide much information about 5-HTP, its
role in the serotonin pathway, recommended dosages, possible side effects, how
it compares to other drugs/antidepressants, and personal experiences.
I have chosen a sampling of them and summarized them in order to
provide an overall idea of the types of 5-HTP sites that have been created.
These were relatively easy to understand and some even seemed to have
some scientific basis behind their claims.
It is from these websites that most of the above information was
All Natural Health – This organization
provides 30-100 mg capsules of 5-HTP for $16.00.
They claim that anywhere from 100-900 mg 5-HTP can safely be taken
daily, depending on the symptoms and needs of the individual.
They declare that 5-HTP also relieves depression and pain in addition
to preventing carbohydrate cravings.
Natural Health’s website describes that 5-HTP works due to the fact that it
can be used to increase the synthesis of 5-HT in the brain, preventing
cravings. All Natural Health
promotes the use of 5-HTP because they say it has been proven to be sufficient
in fulfilling the roles of antidepressants without the negative side effects.
They claim that these antidepressants “may reduce serotonin stores
and impair its release, resulting in less serotonin in the brain,” and thus
are inferior to 5-HTP.
– This New Zealand-based
organization is selling 30 capsules of 5-HTP for $18.35.
Each capsule contains 50 mg 5-HTP and 10 mg St. John’s Wort, which
they say might enhance the effects of the 5-HTP and also induces tranquility.
10 mg Vitamin B6 is also included since it is utilized in the
conversion of 5-HTP to 5-HT. Finally, a form of Vitamin B3 used to convert tryptophan to
5-HTP, and calcium citrate and magnesium hydroxide, which have sedative
effects, are included in each capsule. They
sell their product as a drink mix as well.
Altered States website claims that the supplements they produce are related to
decreased depression, improved sleep, reduced anxiety, migraine relief, and
decreased carbohydrate cravings/weight loss.
They support their claims about all of these conditions by discussing
studies in which those with these ailments were treated with 5-HTP.
In each of the studies, beneficial results associated with the
administration of 5-HTP were found.
States says that the effects of the supplement vary according to each
individual, are safe, and that possible side effects are rare and include
headaches, congestion, mild stomach aches, and constipation.
– Health Locker markets a
product called ProSlim VX5, which is a combination of Vanadium, 5-HTP, and
Chromium. They sell 60 capsules
for $29.90. The Health Locker
website explains the effectiveness of ProSlim VX5 as being the result of “assisting
the body in regulating healthy levels of serotonin.” By producing 5-HT using its precursor (5-HTP) instead of by
overeating carbohydrates, appetite control is much more manageable.
The role of Vanadium and Chromium is supposedly to enhance the burning
of calories and the effects of the 5-HTP.
Health Locker warns that nervousness, tremor, sleeplessness, or nausea
are possible side effects and recommend reducing or discontinuing use of the
supplement if these should occur. They
also warn that those who are pregnant, have high blood pressure, heart or
thyroid disease, diabetes, difficulty urinating, or are taking an MAO
inhibitor or other prescription drug should consult a doctor before use.
This organization sells 90 capsules for $24.90.
This website provides an extensive scientific discussion about the role of
serotonin and other neurotransmitters in the brain, including information
about the effects of 5-HT deficiency. They
explain that when one is feeling anxious or depressed, he or she tends to
crave and overeat carbohydrates, which releases insulin, inducing 5-HT
production and a temporary state of well-being, as described above. The major problem is that this insulin also amplifies the
conversion of the carbohydrates into body fat, resulting in weight gain.
Smartbodyz website also describes in detail the conversion of tryptophan to
5-HT. It supports its claims
about the effectiveness of 5-HTP in treating depression and overeating by
describing studies in which treatment with 5-HTP proved to be favorable.
Finally, this website describes why 5-HTP is more effective than and
superior to other antidepressants, or SSRI’s (serotonin-selective re-uptake
inhibitors), such as Prozac. They
argue that the reason for this is because the SSRI’s merely prevent the
re-uptake of 5-HT present in the synapse, causing in a higher concentration of
it in the brain. In contrast, 5-HTP works by actually increasing the production
of serotonin. (Why this is
preferred is not described.)
– In addition to providing
the typical information about 5-HTP, this website provides many detailed
questions and answers that users have had concerning the product and their
personal experiences with it. It
provides useful information about things like dosages, side effects, etc.
Here are some other 5-HTP
links that may be found useful for those with an interest in this supplement:
(includes excellent extensive discussion of possible complications and
conditions that are potentially dangerous while taking 5-HTP.)
DO THESE SOURCES HAVE ANY REAL SCIENTIFIC BASIS, OR IS
5-HTP MERELY ANOTHER WEIGHT-LOSS SCAM?
Research to discover if any of
the above claims about 5-HTP and its role in weight loss have any truth
revealed the following about the supplement:
From 1989 through 1998, a group
of Italian scientists from the University of Rome La Sapienza did a series of
four studies on the effects of 5-HTP on overweight and obese adults.
The first was a study focusing on feeding behavior.
It was a double-blind study including 19 obese female adults with Body
Mass Indexes between 30 and 40. Half
of the subjects was given 5-HTP while the other half was given a placebo.
Each took the medication for 5 weeks, a week passed with no medication
to avoid carry-over effect, and then a second 5-week period passed in which
the medication was administered again. There
were no dietary restrictions at all placed on the subjects.
Diet diaries were kept by the subjects in order to keep track of food
intake, eating behavior, and anorexic symptoms.
Anorexic symptoms included meat aversion, taste and smell alteration,
nausea, vomiting, and early satiety. Twice
each week, each patient completed a self-evaluation of appetite and satiety at
lunchtime. Those who had any one
of the anorexic symptoms were determined to be anorectic.
To ensure that any change in psychological status of a subject could
not be considered an explanation for any reported changes in food intake and
eating behaviors, depression and anxiety tests were administered to each
subject before and after each study period.
The results of the study proved
to be in favor of the hypothesis that 5-HTP causes a decrease in food intake
and earlier satiety, resulting in a loss of weight.
The group taking 5-HTP consumed significantly fewer calories than the
placebo group. In addition to
this, carbohydrate intake of the 5-HTP group was also significantly less that
that of the placebo group; protein intake remained constant in both groups.
Anorexic symptoms were reported in about 78% of the 5-HTP group as
opposed to only 30% in the placebo group.
The degree of satiety was determined to be higher among the 5-HTP group
than the placebo group. Finally, the amount of weight lost was significantly higher
in the 5-HTP group than in the placebo group.
No differences of psychological status were recorded in any of the
The scientists who carried out
this experiment attributed the results of the experiment to the increase of
serotonin in the brain induced by the 5-HTP supplements.
It was also mentioned that compared to studies utilizing tryptophan
similarly, a much lower dose of 5-HTP was used than tryptophan, yet more than
three times as much weight was lost. This
indicates that 5-HTP is more effective than tryptophan for weight loss.
In conclusion, the scientists who carried out this experiment stated
that “the good tolerance to 5-HTP suggests that this substance may be safely
utilized in the long-term treatment of obesity” (Cairella M et al., 1989)
The second study carried out by
the Italian scientists was very similar to the first, but focused more on
whether or not subjects were able to abide by dietary restrictions placed on
them during the second 6-week period. During
this period, only 1200 calories were to be consumed by both the 5-HTP and
The results of this study were
similar to those of the first. Anorexic
symptoms were again more prominent in the 5-HTP group, as was earlier satiety
and reduced food intake. In the
second 6-week period, the 5-HTP group almost doubled their weight loss, while
the placebo group did not lose any weight at all.
These results suggest that 5-HTP was responsible for the 5-HTP subjects’
better adherence to the dietary restrictions.
A notable side effect in this experiment was nausea, but it stopped
occurring in the second 6-week trial, insinuating that it is only a temporary
side effect (Cairella M et al., 1991).
The third study was essentially
the same as the second, focusing on abidance to dietary restrictions, but this
study also examined the types of food consumed by each group.
The results were again similar to the first two studies.
But this time, it was noted that 5-HTP subjects decreased their
carbohydrate intake by 50% in the first 6-week period, and then another
notable decrease occurred in the second 6-week period.
There was no reduction in carbohydrate intake by the placebo group.
The scientists interpreted these results to mean that “the
administration of 5-HTP was in fact followed by a reduction of both daily
total energy and carbohydrate intakes followed by a significant loss of body
weight” (Antonucci F et al., 1992).
The final study carried out by
the Italian scientists was again similar to the first three.
However, this study utilized overweight non-insulin dependent diabetic
patients (NIDDM) as its subjects since this disease causes a reduced level of
serotonin in the brain, leading to carbohydrate craving and overeating.
The low concentration of brain serotonin is most likely the result of
the unavailability of tryptophan, which occurs in NIDDM.
The administration of 5-HTP to NIDDM patients was effective in reducing
their carbohydrate cravings and essentially resulted in the loss of weight.
The Italian scientists concluded that a combination of these results
along with similar results to a second more
long-term study including a larger sample could implicate 5-HTP as a method
for of “NIDDM patients to achieve a better metabolic control” (Angelico F
et al., 1998).
Evidently, all of these studies
support the use of 5-HTP as an effective way of promoting weight loss by
increasing serotonin in the brain and thus decreasing carbohydrate cravings.
However, in contrast to the findings of the third study discussed
above, a study done in The Netherlands challenges the declaration that weight
loss is due to reduced carbohydrate craving. This study tested the hypothesis that “serotoninergic drugs
would induce a greater weight loss in carbohydrate craving (CC) than in
non-carbohydrate craving (NC) obese patients” (Elte-de Wever BM et al.,
1996). In this study, it was
found that even under the influence of serotoninergic drugs, both CC and NC
subjects lost the same amount of weight, suggesting that serotonin-induced
weight loss is not
specifically carbohydrate-related, as the Italian studies
implied. Nevertheless, this study
emphasizes the idea that drugs that increase brain serotonin do
indeed promote weight loss.
Many studies in addition to
these reiterate the fact that drugs used to increase brain serotonin lead to
decreased cravings and earlier satiety (Alexander JT et al., 1998; Cooper TB
et al., 2000; Cowen PJ et al., 1999; Fernstrom JD et al., 2000).
Examples of these drugs are fenfluramine, fluoxetine, norfenfluramine.
Whether or not this occurs because of a decrease in specifically carbohydrate
cravings needs to be further researched, since discrepancies about this exist.
But despite this, there is
considerable evidence that brain serotonin-increasing drugs, and therefore
5-HTP, are an effective way to treat obesity and in promoting weight loss.
After extensive researching,
nothing was found that greatly invalidated the claims made on 5-HTP, either on
the web or in medical journals. However,
since the focus on this supplement is relatively recent, and because medical
research on 5-HTP is so limited right now, it is probably smart to wait until
further research information on 5-HTP becomes available before using it.
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