Introduction

The use of over-the-counter weight loss pills has reached an all time high. A 2007 study that surveyed over 4,000 people found over 15% had taken some sort of "herbal" weight loss product during the past year. Use of such supplements was much more common in females, at over a 2:1 ratio. Of all respondents, over 75% of them had taken a product containing either ephedrine, caffeine or bitter orange extract. These products are not only used by those seeking to lose weight, but also by athletes looking to boost their performance.

Most people are already familiar with caffeine, and ephedrine came into the media spotlight several years ago when several people died from overdoses and it was subsequently banned for sale in the United States (it is now available again, but only in extremely small doses). But when you see "Bitter Orange Extract" on a label, you probably just assume "hey, it says orange, that HAS to be healthy!". Unfortunately, in the unregulated world of dietary supplements, things are not always as they seem.

Synephrine, The New Ephedra?

After ephedra-containing products were banned in the United States, there was an almost immediate surge of products containing the mysterious ingredient "Bitter Orange Extract". An herb that had been "used for centuries in China" was making claims of burning fat, increasing energy levels, speeding up the metabolism and promoting weight loss. When people point out to me that something was very popular hundreds of years ago, I like to point to the fact that hundreds of years ago we also burned people at the stake for being witches.

The chemical synephrine (also known as sour orange, bitter orange or Zhi Shi) is derived from the fruit of a citrus tree, Citrus aurantium. It is very similar in composition to ephedrine, with the only difference being the location of the hydroxyl group (The hydrogen and oxygen molecules bonded together by a covalent bond). And we all remember how good for you ephedra turned out the be , right?

Also, like ephedra, synephrine can be used to manufacture methamphetamines. Isn't that special...

Does It Work?

The answer to that question seems to be no. There have not been very many studies done of the efficacy of synephrine on weight loss or athletic performance, and the few that have been published show negative results, or at best - inconclusive results. The truth is, very few herbal weight loss supplements can back up their claims with any substantial evidence at all. Some substances such as green tea, chromium picolinate and epehdra have show some minimal benefits in a few studies, but overall have been looked down upon by the scientific community as a whole.

My own personal experience with the product was inadvertent - I bought a "energy drink" from the corner store called "Extreme Shock" on my way out to my morning run. I didn't really read the label closely - I assumed that like most energy drinks it was just another hyper-caffeinated soda. About 15 minutes into my run, I began to get a very uncomfortable feeling crawling across my body - very much like the needles and pins sensation when a foot falls asleep. My skin got very red and flushed, and I had to stop running because (a.) my feet were starting to be in pain from the drink, and (b.) I felt like my heart was about to explode.

I never drank another "Extreme Shock" again, and never gave it another thought until today in my physiology class where we were studying the sympathetic nervous system, talking about how certain chemicals are released when your body goes into the "fight or flight" mode.

Fight or Flight?

When the body is placed under sufficient levels of stress, your body activates its "fight or flight" mechanism - quickly diverting blood and nutrients away from unnecessary systems and towards where it is needed most. You have probable heard of the "adrenaline rush" where a 90 lb woman lifts up a car that fell on someone, or the feeling you get when someone sneaks up behind you and makes a loud noise - the heart pounds, pupils dilate, i.e. the body is preparing to quickly handle an emergency.

Your body jumps into action by releasing a blast of chemicals throughout the bloodstream that react differently to different organs. Systems such as digestion, which are not essential to escaping danger react by using less energy and constricting blood vessels, while other organs such as the heart open blood vessels and start to work harder. This comes on quickly, and generally only lasts for a few minutes - your body isn't designed to operate in that mode for very long.

How It Works

It is believed (there is not a lot known about the pharmacology of synephrine) that it is an adrenogenic antagonist, which means it binds to the same receptors that the chemicals your body produces during fight or flight do. In essence, it "tricks" your body into thinking there is some sort of emergency and releasing norepinephrine and epinephrine, just like during a stressful situation, which increases heart rate and blood flow to the skeletal muscles. Well hey, that sounds like just what every athlete wants, right? Well, that leads us right into our next question...

It It Safe?

One of the biggest dangers in taking these supplements is the fact that they are not regulated. Therefore, it is really impossible to know the exact strength of the dosage you are taking, as you cannot verify the purity of the original ingredients. And because they are sold over the counter, many people don't even think to mention their use to their physician, which can be a dangerous or even deadly mistake.

There have been documented cases of even minimal use of synephrine being linked with heart attacks, seizures, strokes, exercise induced syncope (temporary loss of consciousness/posture), irregular heartbeats, tachycardia (heart beating too fast), cardiac arrest, ventricular fibrillation, transient collapse and blackout.

In once case, a 39 year old professional bodybuilder with no history of heart problems suffered a heart attack in the middle of a competition. It is believed the attack was caused by muscular spasms brought on by the synephrine.

It should be noted that synephrine is a drug used for people with bradycardia (slow heartbeat), several studies have shown that a single dose of synephrine can significantly raise both systolic and diastolic blood pressure even in healthy, young adults for up to 5 hours. When you are exercising, you generally already are pushing your heart to its safe limits - adding on additional blood pressure could prove to be very dangerous during an intense workout.

This also makes it incredibly important to let your doctor or pharmacist know you use one of these products, because there could be dangerous drug interactions, especially for those who already have high blood pressure.

Final Thoughts

To me, it seems to be kind of a no-brainer that you should just avoid this stuff altogether. This sentiment is echoed in numerous medical journals and magazine articles, there simply has not been enough research done to examine either the efficacy or the safety of synephrine.

Until the time comes when a long-term study of a large group of individuals shows benefits with no health risks, it is recommended that you do not use products containing synephrine. Remember - the best way to get more strength and energy are those two worn out words - diet and exercise.

Products To Avoid

I have compiled a list below of many products which contain synephrine. This is not an all-inclusive list, if you have any more additions, just leave a comment below.

Products Containing Synephrine

4Ever Fit 4Ever Burn, Advanced Sport Nutriceuticals Lipex II, All American EFX Lean Fix Elite, Anabolic Xtreme Rampage, ANSI Xtreme Shock, Armor Nutrition Pre-Wired, Avant Labs LipoDerm-Ultra, Avant Research Napalm, Axis Labs Adipo-X, Beast Sports Nutrition 2 Shredded, Beast Sports Nutrition Amphetalean, Beverly Int. 7-Keto MuscLEAN, Bhelliom Enterprises Muscle-Rx, Body Conditioning Solutions Phenyldrene, BSN Thermonex, CMI Fire Caps, CMI NO3 Overload MM5T, D&E Maxadrine, Delta Health Products Yellow Bullet, Designer Supplements Adrenalean, EST ThermoStat, Evolution Labs WinEVOL Rx, Extreme Labs Blade Hardcore, Fizogen The Burn For Men, Fizogen The Burn For Women, Forge Nutrition Adipokinetix, FSI Xenergy, Fusion Health Products Pheninol, Fusion Health Products TriPhase Stack, Gaspari Nutrition Cytolean, German American Technologies Jetfuel, Goliath Labs Thermoloid, Hi-Tech Fastin, Hi-Tech Lipodrene, Hi-Tech Lipodrene-SR, Hi-Tech Stimerex-ES, Hi-Tech Stimerex-ES W/Ephedra, ICOPRO Speed Freak Drink, Irwin Naturals System-Six, Irwin Naturals System-Six Ripped Man, Irwin Naturals Triple-Boost, iSatori Lean System 7, ISS Research Lipovar 8, Labrada Charge Ephedra Free, Met-Rx Amplified Shooter, Metabolic Diet LipoFlush, Metabolic Diet Thermocell 35, Millennium Sport Shred-XS-Hardcore, MP Technologies Thermorexin, MRM Meta-Burn EF, Muscleology Lipoburn, MyoChem Throttle Matrix, Myogenix MyoLean EFX, NOW Energy, NRG-X Labs Red Stinger, NRG-X Labs Red Stinger Extreme, Nutrabolics CLENbutical, Nutrex Ignite, Nutrex Lipo 6, Nutricor Labs Methyl-EFX, Nutrition HQ Tri-Stack, PharmaGenX Ventilean, Powerlab Nutrition C-4, Pride Nutrition Dialed-In, Prolab Therma Pro Ephedra Free, Protein Factory Zip!, Red Dawn Vector Shot, S.A.N. Tight, S.A.N. Tight Xtreme, S.A.N. Tight! Hardcore, Shocker Nutrition Thermo Lean, Spectra Force Research Thermophoric Diet Caps, Sports Nutrition International Performance Pak, Sports Nutrition International Thermalean, Sports One Jacked-Up, Sports One Mahuang RP, Sports One Red-X, STS Metabolic Activator, ThermoLife Stizm, Twinlab Diet Fuel Ephedra Free, Twinlab Ripped Fuel Ephedra Free, Ultimate Nutrition Ultra Ripped, Universal Animal M-Stak, Universal Herbal Thermo Stack E/C/A, Universal HydroBurn SDF, Universal Zero G, VPX Meltdown, Zima Adipo 6.

Please note this is not a complete listing, look for any of the following ingredients on the package: Synephrine (or oxedrine), Bitter Orange Extract, Citrus aurantium (or C. aurantium), Sour Orange, and Zhi shi. Also beware of the words "ephedra-free" on the package, they often indicate the presence of bitter orange extract as a substitute.

Sources Cited

Smedema, J.P., and G.J. Muller. "Coronary spasm and thrombosis in a bodybuilder using a nutritional supplement containing synephrine, octopamine, tyramine and caffeine.(SCIENTIFIC LETTERS)(Letter to the editor)." South African Medical Journal 98.5 (May 2008): 372(2). Academic OneFile. Gale. Eastern Michigan University. 7 Oct. 2008 http://find.galegroup.com.ezproxy.emich.edu/itx/start.do?prodId=AONE.

Louw, Vernon J., and Hymne Louw. "Citrus aurantium--beware of the bitter orange.(Briewe)(Letter to the editor)." South African Medical Journal 98.7 (July 2008): 496(1). Academic OneFile. Gale. Eastern Michigan University. 7 Oct. 2008 http://find.galegroup.com.ezproxy.emich.edu/itx/start.do?prodId=AONE.

Haller, Christine A., Minjing Duan, Peyton Jacob, and Neal Benowitz. "Human pharmacology of a performance-enhancing dietary supplement under resting and exercise conditions.(Report)." British Journal of Clinical Pharmacology 65.6 (June 2008): 833(8). Academic OneFile. Gale. Eastern Michigan University. 7 Oct. 2008 http://find.galegroup.com.ezproxy.emich.edu/itx/start.do?prodId=AONE.

Blanck, Heidi Michels, Mary K. Serdula, Cathleen Gillespie, Deborah A. Galuska, Patricia A. Sharpe, Joan M. Conway, Laura Kettel Khan, and Barbara E. Ainsworth. "Use of nonprescription dietary supplements for weight loss is common among Americans.(Current Research)(Author abstract)." Journal of the American Dietetic Association 107.3 (March 2007): 441(7). Academic OneFile. Gale. Eastern Michigan University. 7 Oct. 2008 http://find.galegroup.com.ezproxy.emich.edu/itx/start.do?prodId=AONE.

Sharpe, Patricia A., Michelle L. Granner, Joan M. Conway, Barbara E. Ainsworth, and Mirela Dobre. "Availability of weight-loss supplements: results of an audit of retail outlets in a Southeastern City." Journal of the American Dietetic Association 106.12 (Dec 2006): 2045(7). Academic OneFile. Gale. Eastern Michigan University. 7 Oct. 2008 http://find.galegroup.com.ezproxy.emich.edu/itx/start.do?prodId=AONE.

:Haaz, S., K.R. Fontaine, G. Cutter, N. Limdi, S. Perumean-Chaney, and D.B. Allison. "Citrus aurantium and synephrine alkaloids in the treatment of overweight and obesity: an update." Obesity Reviews 7.1 (Feb 2006): 79(10). Academic OneFile. Gale. Eastern Michigan University. 7 Oct. 2008 http://find.galegroup.com.ezproxy.emich.edu/itx/start.do?prodId=AONE.

Firenzuoli, F., L. Gori, and C. Galapai. "Adverse reaction to an adrenergic herbal extract (Citrus aurantium)." Phytomedicine: International Journal of Phytotherapy & Phytopharmacology 12.3 (March 2005): 247(2). Academic OneFile. Gale. Eastern Michigan University. 7 Oct. 2008 http://find.galegroup.com.ezproxy.emich.edu/itx/start.do?prodId=AONE.

This Article Entry Was Posted On Tuesday, October 7th at 06:10 pm