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A dietary supplement

 Alexandria N. Duncan

Date: 10/14/2006





Table of Contents:

How does it work?

What are the magic ingredients?

So…Does it really work?

Another Study found …

Is it safe?










Hydroxycut is a dietary supplement that increases weight loss when used in conjunction with exercise. 



 According to, the use of Hydroxycut will induce thermogenesis, a heightened body temperature, which causes calories to burn.  In addition to this, Hydroxycut suppresses the appetite, preserves lean muscle mass, and increases energy levels.


How does it work?

Hydroxycut works by mimicking and intensifying the adrenergic hormones.  As stated on the site Diet pills compared, the human body has three broad heat modulators: the thyroid hormones, adrenergic hormones, and the prostaglandin hormones.  The adrenergic hormones are the modulators that mobilize fatty acids from triglyceride stores and force the skeletal muscles to use more fatty acids for heat production.



What are the magic ingredients?


Hydroxycut’s main active ingredients are Ephedrine and Caffeine.  Other important ingredients include willow bark extract, hydroxycitric acid (HCA), L-carnitine tartrate, and chromium picolinate.

Ephedrine, a derivative of Ephedrine, is a fat burning stimulant that affects the adrenergic receptors of the central nervous system.  Ephedrine increases the level of dopamine that surrounds the hypothalamus, which is an area that is important to body arousal.

Ephedrine works better at burning fat when it is combined with caffeine because it potentiates ephedrine’s effect.  Also, caffeine increases adrenaline levels, which boost the level of energy.  The two kinds of caffeine found in Hydroxycut are green tea extract and guarana.  Green tea contains strong antioxidant compounds called polyphenols.  The strongest polyphenol, epigallocatechin gallate EGCG, prolongs the life of norepinephrine, which triggers thermogenesis.  So, it helps to maintain the process of thermogenesis for a longer period of time, boosts the metabolic rate, and causes fat loss.

Guarana is a bushy tree that grows in the Amazon rainforest and the caffeine it contains is rapidly absorbed by the body and remains in circulation for more than seven hours.  It increases free fatty-acid levels, which provides the body with a fuel source that it can use instead of glycogen.

Willow bark is a natural source of salicin, similar to that found in aspirin.  Willow bark further increases the effects of the epinephrine/caffeine combination by helping to raise the body’s set point for temperature regulation.  The result is a higher basal metabolic rate and increased body fat loss.

Hydroxycitric acid is taken from a Malabar tamarind fruit and its action is to increase the body’s propensity to burn fats while simultaneously decreasing the utilization of carbohydrates for fuel.  It also promotes the production of additional glycogen, which is stored in the skeletal muscles and liver.  There are hunger receptors in the liver, and when there are high levels of glycogen, the intensity of the signals sent to the brain by these receptors decreases.  In turn this causes appetite suppression.

L-carnitine tartrate is a vitamin like compound that facilitates the movement of free-fatty acids to the mitochondria for oxidation through the actions of the enzyme carnitine palmitoyl transferase 1, which helps to stimulate fat burning.

And lastly, chromium picolinate is involved in the metabolism of glucose for energy.  It’s a metal that aids insulin in binding to its compatible receptor sites.





So…Does it really work?




The studies mentioned on the website included one that was funded by Muscle Tech, the creators of Hydroxycut, and led by Arne Astrup, MD at the University of Copenhagen on the effects of ephedrine.  Also, the American Journal of Clinical Nutrition conducted a study with green tea and measured its thermogenic effects.

In the study done on the effects of ephedrine, subjects were placed in one of three groups: 1) a full dose of Hydroxycut taken three times a day with exercise, 2) a placebo taken three times a day with exercise, and 3) a full dose of Hydroxycut with no exercise. 

The results showed that those in group 1 had a greater significant weight loss of 3.8kg than group 2.  And group 3 showed a caloric intake of 680.

In the study done at the University of Copenhagen, five females were administered 20mg of ephedrine three times a day one hour before meals.

The results from this study showed that the women lost about an average of 2.5 kg of body weight after 4 weeks and 5.5 kg after 12 weeks and in addition to this, they were able maintain their muscle mass. After the experiment was terminated, the women had only gained back .5kg, and remember, there was no dieting involved in the experiment.

The study lead by the American Journal of Clinical Nutrition found that green tea taken in the place of caffeine caused thermogenic effects to be stronger.  Over a period of six weeks subjects were evaluated after taking pure caffeine, green tea extract, and a placebo three times a day.  The group that had been administered the green tea experienced a significant increase in thermogenesis of 4% and an increase in overall energy of 4.5%.




Another Study Found on the “Web of Science”

I researched the effects of ephedrine and caffeine on weight loss and found two studies related to this topic.

First, Toubro S, Astrup AV, Breum L, and Quaade F (1993) reviewed the “Safety and Efficacy of long term treatment with ephedrine, caffeine, and ephedrine caffeine mixture”, in which 180 obese patients were treated with one of, or both of the drugs.  After fifty weeks of testing, it was found that patients that received the combination of both ephedrine and caffeine had lost a significant amount of weight, and also, this combination allowed the patients to save lean body mass.



 Is It Safe?


In the study mentioned above, the side effects were minor and transient, and they found no withdrawal symptoms.  In the second study, Haller CA, Jacob P, and Bebowitz NL reviewed the “Enhanced stimulant and metabolic effects of combined ephedrine and caffeine”, and results showed that the combination of ephedrine and caffeine increased systolic blood pressure and heart rate, and raised glucose, insulin, free fatty acid, and lactate concentrations.  The site, Diet pills compared, listed side effects of Hydroxycut and they are as follows:

*nervousness                       * headaches
* dizziness                            * jitters
* tremors                               * palpitations
* rapid heart rate                  * insomnia, and      

* increased blood pressure.


Go to fullsize image Conclusion Go to fullsize image


In researching Hydroxycut, a dietary supplement that is supposed to increase weight loss when used in addition to daily exercise, it can be concluded that Hydroxycut does indeed work.  There can be a significant amount of weight loss during the use of this product.  According to the studies, there are some minor side effects from using this product, but long term testing showed that there were no harmful side effects.  But, the affects of Hydroxycut on the human body after long term use of more than fifty weeks is unknown.



I would recommend that, if you choose to use Hydroxycut, don’t use it for longer than fifty weeks (1yr and 2mos) because the effects of this supplement, if used longer than this time, are unknown.  Also, if you feel abnormal side effects during the use of this supplement, other than what is listed, discontinue use and consult a physician.  Don’t expect a miracle from this pill, even though it’s been proven to work, you still have to exercise and maintain a healthy diet.




















































Toubro S, Astrup AV, Breum L, and Quaade F (1993). Safety and Efficacy of Long-Term Treatment with Ephedrine, Caffeine, and an Ephedrine Caffeine Mixture. International Journal of Obesity, 17, s69-s72.


Haller CA, Jacob P, Benowitz NL (2004).Enhanced stimulant and metabolic effects of combined ephedrine and caffeine. Clinical Pharmacology & Therapeutics 75 (4), 259-273.


Diet Pills Compared. Hydroxycut Review. 2002. Diet Pills Compared. 11 Sept. 2004 < >


Diet Pills Compared. Hydroxycut Side Effects. 2002. Diet Pills Compared. 11 Sept. 2004 < >


Diet Pills Compared. Hydroxycut Results. 2002. Diet Pills Compared. 11 Sept. 2004. < >


Diet Pills Compared. Does Hydroxycut Work. 2002. Diet Pills Compared. 11 Sept. 2004. < >


Consumer Health Digest. Does Hydroxycut Work?. 2004. Consumer Health Digest. 11 Sept. 2004. < >




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