Treatment
Principal Proposed Treatments for Weight Loss:
Chromium
Chromium is a mineral the body needs in only small amounts, but its important
to human nutrition.
Although it has principally been studied for improving blood sugar control in
people with diabetes, chromium has also been tried for reducing body fat. The
results of studies have been mixed. However, whether or not it actually assists
weight loss, chromium may offer heart-healthy benefits for overweight
individuals. Both of these potential benefits involve chromiums effects on
insulin. Before we can explain how chromium may help, we need to provide some
background information on how the body controls its blood sugar levels.
The body needs a constant level of glucose (sugar) in the blood. When you digest
a carbohydrate meal, glucose levels rise. Protein meals have the same effect,
although to a lesser extent. Your body responds by secreting insulin. Insulin
causes the cells of your body to absorb glucose out of the blood, thereby
reducing circulating blood sugar.
Once cells have taken in glucose, they can burn it for energy or convert it to a
storage form. Liver and muscle cells can store a limited amount of glucose as
glycogen. Fat cells can convert unlimited amounts of glucose into energy stored
as fat.
The process also goes the opposite way. When your body has used up the food from
its last meal, blood glucose levels drop. Just as the body doesnt like it when
glucose levels are too high, low glucose levels also cause problems. So your
body applies its control mechanisms to raise blood sugar levels. It does so by
reducing its output of insulin, and also by raising levels of another hormone
called glucagon. The net effect is that energy storage depots are mobilized.
Glycogen is converted back into glucose. In addition, fat cells release their
contents into the bloodstream to supply an alternate energy source.
To summarize: High insulin levels build fat, while low insulin levels break down
fat.
Based on this push-pull effect, if you want to lose weight youd probably rather
keep your insulin levels low.
Dieting is the most obvious method of reducing insulin. When you dont take in
enough calories to supply your bodys daily needs, insulin levels fall and your
body breaks down fat cells. Exercising is another method: By increasing your
bodys energy requirements, exercise causes insulin levels to fall and fat cells
to break down.
But its difficult to consistently use more energy than you take in. Hunger
takes over, and you start wanting to eat. If there were some way to trigger fat
breakdown without going hungry, it would make weight loss much easier.
Theres another important connection between insulin and weight to consider.
Individuals who weigh too much often develop insulin resistance. In this
condition, certain cells of the body become less sensitive to insulin. The body
senses this, and increases insulin production until it overcomes the resistance.
It is possible that fat cells respond to these increased levels of insulin by
storing even more fat.
This is the point where chromium comes in.Chromium is thought to improve the
bodys responsiveness to insulin. Combining this fact with the insulin–weight
connections just described, some researchers have proposed that chromium may
assist in weight loss.
Their main argument goes like this: Chromium increases insulin sensitivity. This
causes levels of insulin to fall. With reduced amounts of insulin in the blood,
fat cells are less inclined to store fat, and weight loss may become easier.
In addition, there is some evidence that chromium partially blocks insulins
effects on fat cells, interfering with its fat-building effect. This too could
assist weight loss.
However, there are several flaws in these arguments. For example, even very
small amounts of insulin in the blood effectively suppress fat breakdown.
Another problem is that during insulin resistance, fat cells also appear to
become resistant to insulin. Insulin resistance, in other words, might be a
natural method of keeping the lid on weight gain. Chromium supplements might
have the undesired effect of increasing the ability of fat cells to respond to
insulin, helping them store fat better!
However, theory only takes one so far. It is more important to review the
results of studies in which people were given chromium supplements to reduce
their weight.
What is the Scientific Evidence for Chromium?
Weight Loss In one study, 154 individuals were given either placebo or 200 or
400 mcg of chromium picolinate daily.7 Participants were not advised to follow
any particular diet. Over a period of 72 days, individuals taking chromium
experienced significantly greater weight loss than those not taking chromium,
over 2-1/2 pounds versus about 1/4 pound. Interestingly, individuals taking
chromium actually gained lean body mass, so the loss of fatty tissue was even
more dramatic: over 4 pounds versus less than 1/2 pound.
Another double-blind study by the same researcher, however, failed to
demonstrate benefit. In this 3-month trial, 122 moderately overweight
individuals attempting to lose weight were given either placebo or 400 mcg of
chromium daily. No statistically significant differences were seen between
groups. Researchers had to resort to fairly complicated statistical maneuvers in
an attempt to show some benefit.
Seven other double-blind, placebo-controlled studies also failed to find
evidence of benefit with chromium picolinate. One possible explanation for these
discrepancies could be that chromiums effects are relatively slight and can
only be demonstrated in larger trials.
Heart-Healthy Effects for Overweight Individuals Whether or not it improves
weight loss, chromium might offer health benefits for overweight individuals.
As described above, overweight individuals frequently become resistant to their
own insulin. The body responds by releasing more and more insulin. Sooner or
later, however, this compensating mechanism reaches a limit, and cells simply
find it hard to absorb glucose from the bloodstream. The result is a rise in
blood sugar levels.
Even when mild, this condition dramatically increases risk of heart disease. The
risk goes up still further when insulin resistance becomes severe and develops
into type 2 (adult-onset) diabetes.
Weight loss almost always improves insulin resistance. It appears that chromium
supplements may also help.
In a double-blind, placebo-controlled study, 180 people with type 2 diabetes
were given placebo, 200 mcg of chromium picolinate daily, or 1,000 mcg of
chromium picolinate daily. Individuals taking 1,000 mcg showed marked
improvements in blood sugar levels. Lesser but still significant benefits were
also seen in the 200-mcg group, but not in the placebo group.
Many other studies have been performed on chromium supplementation in both
diabetes and glucose intolerance. The results have been mixed, perhaps because
most of these studies were relatively small. Nonetheless, overall, chromium is a
promising treatment for improving mild glucose intolerance. For this reason,
overweight individuals might benefit from supplemental chromium, even if it
doesnt help them lose weight.
For more information, including dosage and safety issues, see the full chromium
article.
Pyruvate
Pyruvate supplies the body with pyruvic acid, a natural compound that plays
important roles in the manufacture and use of energy. Theoretically, taking
pyruvate might increase the bodys metabolism, particularly of fat. However, the
evidence that it works is limited to small studies. Some of these trials also
used dihydroxyacetone, a chemical closely related to pyruvate.
What Is the Scientific Evidence for Pyruvate?
Weight Reduction Several small studies enrolling a total of about 150
individuals have found evidence that pyruvate or DHAP (a combination of pyruvate
and dihydroxyacetone) can aid weight loss and/or improve body composition.
For example, in a 6-week double-blind placebo-controlled trial, 51 individuals
were given either pyruvate (6 g daily), placebo, or no treatment. All
participated in an exercise program. In the treated group, significant decreases
in fat mass (2.1 kilograms) and percentage body fat (2.6%) were seen, along with
a significant increase in muscle mass (1.5 kilograms). No significant changes
were seen in the placebo or nontreatment groups.
Another placebo-controlled study (blinding not stated) used a much higher dose
of pyruvate, 22 to 44 g daily depending on total calorie intake. In this trial,
34 slightly overweight individuals were put on a mildly weight-reducing diet for
4 weeks. Subsequently, half were given a liquid dietary supplement containing
pyruvate. Over the course of 6 weeks, individuals in the pyruvate group lost a
small amount of weight (about 1-1/2 pounds) while those in the placebo group did
not lose weight. Most of the weight loss came from fat.
Another interesting placebo-controlled study evaluated the effects of DHAP when
individuals who had previously lost weight increased their calorie intake.
Seventeen severely overweight women were put on a restricted diet as inpatients
for 3 weeks, during which time they lost approximately 17 pounds. They were then
given a high-calorie diet. Approximately half of the women also received 15 g of
pyruvate and 75 g of dihydroxyacetone daily. The results found that after 3
weeks of this weight-gaining diet, individuals receiving the supplements gained
only about 4 pounds, as compared to about 6 pounds in the placebo group. Close
evaluation showed that pyruvate specifically blocked regain of fat weight.
While all these studies are intriguing, we really need large studies (100
participants or more) to establish the benefits of pyruvate for weight loss.
For more information, including dosage and safety issues, see the full pyruvate
article.
Fiber
Dietary fiber is important to many intestinal tract functions including
digestion and waste excretion. It also appears to have a mild
cholesterol-lowering effect and might help reduce the risk of some kinds of
cancer (although the current evidence is a bit contradictory).
Fiber might also be useful for losing weight. Its thought to work in a simple
way: by filling the stomach and causing a feeling of fullness, while providing
little to no calories. Fiber might also interfere with absorption of fat.
There are two kinds of fiber: soluble fiber, which swells up and holds water,
and insoluble fiber, which does not. Soluble fiber is found in psyllium seed
(sold as a laxative), apples, and oat bran. Most other plant-based foods contain
insoluble fiber.
Fiber supplements may contain a variety of soluble or insoluble fibers from
grain, citrus, vegetable, and even shellfish sources.
What Is the Scientific Evidence for Fiber Supplements?
Several double-blind, placebo-controlled studies have evaluated fiber
supplements as a weight-loss aid. The results have been somewhat inconsistent,
but in general it appears that some forms of fiber may assist weight loss.
In one of the largest studies, 97 mildly overweight women on a strict
low-calorie diet were given either placebo or an insoluble fiber (type not
stated) 3 times daily for 11 weeks. Women given fiber lost almost 11 pounds
compared to about 7 pounds in the placebo group. Participants using the fiber
reported less hunger.
Researchers werent finished with their subjects! For an additional 16 weeks,
their diet was changed to one that supplied more calories. As expected,
participants regained some weight during this period. Nonetheless, by the end of
the 16 weeks, individuals taking fiber were still 8 pounds lighter than at the
beginning of the study, while those taking placebo were only 6 pounds lighter.
Another study evaluated whether the benefits of dietary fiber endure over 6
months of dieting. This double-blind trial of 52 overweight individuals found
that use of an insoluble, dietary fiber product (made from beet, barley, and
citrus) almost doubled the degree of weight loss as compared to placebo. Once
more, participants using the fiber supplement reported less hunger.
Two other double-blind placebo-controlled studies evaluated a similar insoluble
fiber product. The first enrolled 60 moderately overweight women and put them on
a 1,400-calorie diet along with placebo or fiber for a period of 2 months. The
other study was similar, but enrolled only 45 women and followed them for 3
months. The results of both studies again showed improved weight loss and
reduced feelings of hunger in the treated groups. However, a 24-week study of 53
moderately overweight individuals found no difference in effect between placebo
and 4 g of insoluble fiber daily.
Glucomannan, a source of soluble dietary fiber from the tubers of Amorphophallus
konjac, has also been tried for weight loss, with positive results in adults. In
a double-blind placebo-controlled trial of 20 overweight individuals,
researchers found that use of glucomannan significantly improved weight loss
over an 8-week period. Benefits were also seen in a double-blind
placebo-controlled trial of 28 overweight individuals who had just experienced a
heart attack. However, another trial studied the effectiveness of glucomannan as
a weight-loss agent in 60 overweight children, and found no benefit.
An 8-week double-blind placebo-controlled trial of 59 overweight individuals
evaluated the effects of chitosan, a mostly insoluble fiber from crustaceans,
taken at a dose of 1.5 g prior to each of the two biggest meals of the day. No
special diets were assigned. The results showed that, on average, participants
in the placebo group gained more than 3 pounds over the course of the study,
while those taking chitosan lost more than 2 pounds.
In contrast, an 8-week double-blind placebo-controlled trial of 51 women found
that use of chitosan at a dose of 1,200 mg twice daily failed to cause any
weight loss.
Similarly, in a 28-day double-blind trial of 30 overweight individuals, chitosan
taken at a dose of 1 g twice daily did not induce weight loss. The shorter
duration, lower dosage, and smaller number of participants in this trial may
account for the lack of results.
A few trials have only evaluated effects on hunger and satiety rather than
weight loss. One study found that the soluble fiber pectin (from apples) reduces
hunger sensations. Another found that the soluble fiber guar gum slows stomach
emptying and increases the sensation of fullness. However, a more recent study
evaluated the effects of guar gum in 25 women undergoing a weight-loss program,
and found no influence on hunger.
Dosage
The optimum dose of fiber and the proper time to take it have not been
determined.
In the first three studies described previously, insoluble fiber supplements
were given 20 to 30 minutes prior to each meal at a dose of about 2.3 g, along
with a large glass of water. For additional dosage information, see the full
articles on glucomannan and chitosan.
Safety Issues
Fiber supplements must be taken with water; otherwise they may block the
digestive tract. Even when used properly, mild gastrointestinal side effects
such as gas and bloating may occur.
As a kind of positive side effect, fiber supplements may reduce cholesterol and
blood pressure levels.
For other important safety issues, see the full articles on chitosan and
glucomannan.
5-HTP
Serotonin is an important chemical in the brain. Although theres much we dont
know about how it works, serotonin is thought to play a major role in numerous
conditions, including depression and anxiety. Drugs in the Prozac family
increase serotonin levels, an action believed to play a major role in how they
work.
Serotonin is also thought to influence appetite and eating behavior.
Fenfluramine, the infamous "fen" part of "fen-phen," acts somewhat similarly to
Prozac. When combined with phentermine ("phen"), it was, in some peoples
opinion, the most effective weight-loss agent ever discovered. Unfortunately,
fenfluramine had to be taken off the market because it caused damage to the
valves of the heart.
Other drugs that raise serotonin have also been tried for weight loss. This fact
has led to such acronyms as "Proz-phen" and "Zo-phen," for phentermine
combinations involving Prozac and Zoloft.
The supplement 5-HTP (5-hydroxytryptophan) is another option thats drawn
considerable interest since the demise of fenfluramine.
The body manufactures serotonin from 5-HTP. Therefore, it is reasonable to
suppose that taking supplemental 5-HTP will enhance serotonin production.
Indeed, preliminary evidence suggests that 5-HTP has antidepressant properties,
perhaps to the same extent as drugs in the Prozac family.
Several studies suggest that 5-HTP might aid weight loss as well.
What Is the Scientific Evidence for 5-HTP (5-Hydroxytryptophan)?
A total of four small double-blind placebo-controlled clinical trials have
examined whether 5-HTP can aid weight loss.
The first of these, a double-blind crossover study, found that use of 5-HTP (at
a daily dose of 8 mg per kilogram body weight) reduced caloric intake despite
the fact that the 19 participants made no conscious effort to eat less.
Participants given placebo consumed about 2,300 calories per day, while those
taking 5-HTP ate only 1,800 calories daily. Use of 5-HTP appeared to lead to a
significantly enhanced sense of satiety after eating. Over the course of 5
weeks, women taking 5-HTP effortlessly lost over 3 pounds.
A follow-up study by the same research group enrolled 20 overweight women who
were trying to lose weight. Participants received either 5-HTP (900 mg per day)
or placebo for two consecutive 6-week periods. During the first period, there
was no dietary restriction, while during the second participants were encouraged
to follow a defined diet expected to lead to weight loss.
Participants receiving placebo did not lose weight during either period.
However, those receiving 5-HTP lost about 2% of their initial body weight during
the no-diet period, and an additional 3% while on the diet. Thus, a woman with
an initial weight of 170 pounds lost about 3-1/2 pounds after 6 weeks of using
5-HTP without dieting, and another 5 pounds while dieting. Once again,
participants taking 5-HTP experienced quicker satiety.
Similar benefits were seen in a double-blind study of 14 overweight women given
900 mg of 5-HTP daily.
Finally, a double-blind placebo-controlled study of 20 overweight individuals
with adult-onset diabetes found that use of 5-HTP (750 mg per day) without
intentional dieting resulted in about a 4-1/2 pound weight loss over a 2-week
period. Use of 5-HTP reduced carbohydrate intake by 75% and fat intake to a
lesser extent.
Unfortunately, all these studies were performed by a single research group. In
science, results arent considered valid until they are independently replicated
by different researchers. In addition, all these studies were small in size. For
these reasons, further research is necessary before we can consider 5-HTP a
proven weight-loss agent.
For more information, including dosage and safety issues, see the full 5-HTP
article.
Other Proposed Treatments for Weight Loss:
Calcium and Vitamin D Supplements
Rapid weight loss in overweight postmenopausal women appears to accelerate
osteoporosis slightly. For this reason, taking calcium and vitamin D
supplements—always a good idea—may be especially appropriate here.
Interestingly, there is some evidence that calcium supplements might also
facilitate weight loss to some extent, for reasons that arent clear.
Garcinia cambogia
Hydroxycitric acid (HCA), a derivative of citric acid, is found primarily in a
small, sweet, purple fruit called Garcinia cambogia, the Malabar tamarind.
Although animal and test tube studies as well as one human trial suggest that
HCA might encourage weight loss, other studies have found no benefit. In an
8-week double-blind placebo-controlled trial of 60 overweight individuals, use
of HCA at a dose of 440 mg 3 times daily produced significant weight loss as
compared to placebo.
In contrast, a 12-week double-blind placebo-controlled trial of 135 overweight
individuals, who were given either placebo or 500 mg of HCA 3 times daily, found
no effect on body weight or fat mass. However, this study has been criticized
for using a high-fiber diet, which is thought to impair HCA absorption.
Other small placebo-controlled studies found HCA had no effect on metabolism,
appetite, or weight.
The bottom line: It is not yet clear whether Garcinia cambogia is an effective
treatment for weight loss.
Caffeine and Ephedrine
Caffeine and ephedrine (found in ephedra, an herb also known as ma huang) are
central nervous system stimulants. Considerable evidence suggests
ephedrine/caffeine combinations can assist in weight loss.
For example, in a double-blind placebo-controlled trial, 180 overweight
individuals were placed on a weight-loss diet and given either
ephedrine/caffeine (20 mg/200 mg), ephedrine alone (20 mg), caffeine alone (200
mg), or placebo, 3 times daily for 24 weeks. The results showed that the
ephedrine/caffeine treatment significantly enhanced weight loss, resulting in a
loss of more than 36 pounds as compared to only 29 pounds in the placebo group.
Neither ephedrine nor caffeine alone produced any benefit. Contrary to some
reports, participants did not develop tolerance to the treatment. For the whole
6 months of the trial, the treatment group maintained the same relative weight
loss advantage over the placebo group.
We dont know exactly how ephedrine/caffeine works. However, caffeine has
actions that cause fat breakdown and enhance metabolism. Ephedrine suppresses
appetite and increases energy expenditure. The combination appears to produce
synergistic effects, with appetite suppression probably the most important
overall factor.
Note: These stimulants, especially when combined, affect the heart.
Ephedrine/caffeine combinations should only be used under physician supervision.
In addition, whole ephedra herb may contain other chemicals that present risk.
See the full ephedra article for more information.
Vitamin C
Vitamin C, the single most popular vitamin supplement in the United States, has
been tested in hundreds of clinical studies for dozens of illnesses from cancer
to colds, and even for weight loss.
Results of two small double-blind placebo-controlled studies suggest that
significantly overweight people who take vitamin C supplements may lose some
weight, but larger studies will have to be conducted before these results can be
taken as recommendations.
Evening Primrose Oil
Evening primrose is a native American wildflower, named for the late afternoon
opening of its delicate flowers. Its seeds are one of the best natural sources
of cis-gamma-linolenic acid (GLA), an important member of the essential omega-6
family of fatty acids.
A 12-week double-blind study that enrolled 100 significantly overweight women
compared the effectiveness of evening primrose oil to placebo. No difference was
seen between the groups. However, there was a high dropout rate in this trial
(over 25%), which somewhat decreases the meaningfulness of the results. In
addition, many participants were known to have "refractory obesity," meaning
that they had already failed to respond to other forms of treatment.
Another double-blind trial tested the unusual hypothesis that evening primrose
might only work in individuals with a family history of obesity. A total of 47
people with a family history of obesity were enrolled in this study. The results
showed that use of evening primrose oil produced a small but significant loss of
weight. Interestingly, participants whose parents were both obese showed even
better response.
Considering the contradictory nature of this evidence, more research is
necessary to determine whether evening primrose oil is really useful for weight
loss.
Conjugated Linoleic Acid (CLA)
Conjugated linoleic acid (CLA) is a mixture of different isomers, or chemical
forms, of linoleic acid. This is an essential fatty acid—a type of fat that your
body needs as much as it needs vitamins.
CLA has been proposed as a fat-burning substance, but the evidence that it works
is mixed at best.
Medium-Chain Triglycerides (MCTs)
Some evidence suggests that MCT consumption might enhance the bodys natural
tendency to burn fat. This has led to investigations of MCTs as a weight-loss
aid. However, the results of clinical trials thus far have not been impressive.
In a 4-week double-blind placebo-controlled trial, 66 women were put on a very
low-carbohydrate diet to induce ketosis. Half of the women received a liquid
supplement containing ordinary fats; the other half received a similar
supplement in which the ordinary fats were replaced by MCTs.
The results indicated that the MCT supplement significantly increased the rate
of "fat burning" during the first 2 weeks of the trial and also reduced the loss
of muscle mass. However, these benefits declined during the last 2 weeks of the
trial, which suggests that the effects of MCTs are temporary.
In other trials, substitution of MCTs for ordinary fats in a standard
low-calorie diet failed to enhance weight loss.
Other Treatments
Preliminary evidence suggests that a special type of fat known as diacylglycerol
may help individuals lose fat, especially fat around the abdomen.
One double-blind placebo-controlled trial investigated the possible weight-loss
effects of spirulina. However, while individuals taking 8.4 g of spirulina daily
lost weight, the difference between the spirulina group and the placebo group
was not statistically significant. Larger and longer studies are needed to
establish whether spirulina is indeed an effective treatment for obesity.
A double-blind placebo-controlled trial that enrolled 158 moderately overweight
volunteers tested a mixture of chromium, cayenne, inulin (a nondigestible
carbohydrate), and phenylalanine (an amino acid), as well as other herbs and
nutrients. All participants lost weight over the 4-week trial. Those using the
supplement lost a bit more weight, but the difference was not mathematically
significant. However, a bit of positive news came from close examination of
results. Among those taking the supplement, a significantly higher percentage of
the weight loss came from fat instead of muscle.
Weight-loss benefits were seen in a double-blind trial of 150 overweight
individuals given either placebo or one of two doses of a combination therapy
containing chitosan, chromium, and Garcinia cambogia. Benefits were also seen in
a 45-day double-blind placebo-controlled trial of 44 overweight people that
tested a combination product containing yerbe mate, guarana, and damiana.
A double-blind placebo-controlled study evaluated the effects of a mixture
containing Citrus aurantium (bitter orange), caffeine, and St. Johns
wort.Citrus aurantium contains various stimulant chemicals related to nasal
spray decongestants. The results suggest that this combination might assist
weight loss, but the study was so small (23 participants divided into three
groups) that the results mean little.
One small double-blind study suggests that use of colostrum by healthy men and
women undergoing exercising training may improve body composition as compared to
whey protein.
A rather theoretical study found that two ingredients in green tea may interact
to increase metabolism.
An enormous number of other supplements are marketed for weight loss. Most have
little to no evidence behind them, and some have been found ineffective in
preliminary studies. For example, certain supplements are said to be lipotropic,
meaning that they help your body metabolize fat or slow down the rate at which
its stored. Vitamins B5 and B6, biotin, choline, inositol, lecithin, and lipoic
acid are often placed in this category. However, there is no real evidence that
theyll help you lose weight.
Beans partially interfere with the bodys ability to digest carbohydrates, which
is why they cause flatulence. Based on this, products containing the French
white bean Phaseolus vulgaris have recently been widely marketed as
carbohydrate-blockers. However, there is no evidence that this treatment (or any
other bean) actually aids weight loss.
A number of amino acids are said to reduce hunger, including phenylalanine,
tyrosine, methionine, and glutamine. Because the herb kava appears to be helpful
for anxiety, it has been proposed as a treatment for mood-related overeating.
The antidepressant herb St. Johns wort has been recommended with much the same
reasoning.
Seaweeds such as kelp, bladderwrack, and sargassi are often added to diet
formulas, under the assumption that they will affect the thyroid gland through
their iodine content. However, the effect of iodine on thyroid function depends
on whether you are iodine deficient. Excess iodine can actually suppress the
action of the thyroid. The herb guggul (Commiphora mukul) is often claimed to
enhance thyroid function, and for this reason it is often sold as a weight-loss
agent. However there is little evidence that it actually affects the thyroid,
and a small double-blind trial found it no more effective than placebo for
weight loss.
Numerous herbs and supplements with potential or known effects on insulin are
widely added to weight-loss formulas, again, without any evidence that they are
effective. These include alfalfa, Anemarrhena asphodeloides, arginine,
Azadirachta indica (neem), bilberry leaf, bitter melon (Momordica charantia),
Catharanthus roseus, Coccinia indica,Cucumis sativus, Cucurbita ficifolia,
Cuminum cyminum (cumin), Euphorbia prostrata, garlic, glucomannan, Guaiacum
coulteri, Guazuma ulmifolia, guggul, holy basil (Ocimum sanctum), Lepechinia
caulescens, Musa sapientum L. (banana), nopal cactus (Opuntia streptacantha),
onion, Psacalium peltatum, pterocarpus, Rhizophora mangle, salt bush, Spinacea
oleracea, Tournefortia hirsutissima,Turnera diffusa, and vanadium.
Herbs with laxative or diuretic properties or reputations are also popular in
weight-loss formulas, although they are unlikely to produce anything beyond a
slight temporary effect. These include barberry, buchu, cascara sagrada bark,
cassia powder, cleavers, cornsilk, couchgrass, dandelion root, fig, goldenrod,
hydrangea root, juniper berry, peppermint, prune, senna leaf, tamarind, turkey
rhubarb root, and uva ursi.
Herbs supposed to "strengthen" the body in general are found in many diet
formulas, including ashwagandha, cordyceps, Eleutherococcus, fo-ti, ginseng,
maitake, reishi, schisandra, and suma.
Other herbs and supplements sometimes recommended for weight loss for reasons
that are unclear include buckthorne, cayenne, chickweed, coenzyme Q10,
cranberry, fennel, flax, ginger, ginkgo, gotu kola, grape seed extract,
hawthorn, licorice, milk thistle, parsley, passionflower, plantain, white
willow, yellow dock, yucca, and zinc.
One small double-blind trial found no benefit with the supplement L-carnitine.
DHEA has been proposed as a weight loss aid, but the little evidence that is
available appears more negative than positive.