The Food and Drug Administration (FDA), a federal watchdog agency, has made it clear that it doesn’t like supplements containing ephedrine or mahuang, a Chinese herb from which ephedrine is derived. Ephedrine is an alkaloid that has a similar structure to amphetamines, or speed. In fact, it shows up as amphetamine on a drug test. Because of its pronounced stimulant effect, ephedrine is banned for use in sport, despite the fact that it’s a naturally occuring substance.
The FDA isn’t concerned with any ergogenic effects associated with ephedrine, however. FDA officials believe that it’s a potentially toxic compound, and based on that assertion, have sought to limit the individual dose of ephedrine to as little as eight milligrams. By comparison, current individual doses average 25 milligrams.
Although the FDA has received several hundred adverse-incident reports related to ephedrine, many have turned out to be either not associated directly with ephedrine or due to a preexisting medical condition. Organizations that support the use of ephedrine point out that because of its stimulant effects, it is contraindicated for people who have medical conditions like high blood pressure, cardiovascular disease, thyroid disease and several others. People who have such medical conditions and still use ephedrine are taking a risk.
About three years ago the FDA suffered a notable setback in its efforts to limit the dosage of ephedrine sold. At that time the General Accounting Office, the investigative division of the United States Congress, examined adverse reports about ephedrine that had been submitted to the FDA and found them inconclusive. That caught the FDA off guard, and the agency was forced to give its campaign against ephedrine a rest.
The FDA is a tenacious agency, however, and recently commissioned an independent study about the adverse effects of ephedrine. It was published in the prestigious New England Journal of Medicine. The study examined 140 adverse reports submitted to the FDA between 1997 and 1999, and the researchers concluded that 31 percent of the cases were either definitely or probably related to ephedrine use, while another 31 percent were possibly related to it.
Of the symptoms reported, 47 percent were cardiovascular, with another 18 percent involving the central nervous system. The specific cardiovascular symptoms included hypertension (17 reports), heart palpitations (13), strokes (10) and seizures (seven). Ten events lead to death, while 13 produced permanent disability.
The authors’ criterion for determining that ephedrine was a ‘definite’ direct cause was whether the symptoms ended when the person stopped using ephedrine or if they returned when he or she used it again. Another criterion was if the reported symptoms coincided with peak blood plasma levels of ephedrine. In terms of cardiovascular effects, 11 people in the study who suffered catastrophic heart problems or strokes had not previously been diagnosed with heart problems.
From the case studies described in the report, it’s difficult to determine just how healthy some of the people were. The doses of ephedrine they used are commonly found in many over-the-counter products; in fact, that’s precisely how the people discussed in the study used ephedrine’they took various commercial supplements that contained it. When you consider that, as noted in the study, at least 12 million people took similar doses of ephedrine in 1999, the obvious question is, Why do some people suffer such terrible side effects?
My feeling is that the people described in this report had cardiovascular disease that had not been diagnosed and that ephedrine, in effect, pushed them over the edge. That’s precisely the real danger of ephedrine: It could lead to serious problems if you have any type of cardiovascular disease and aren’t aware of it. The evidence presented in this report concerning the dangers of ephedrine use for people who don’t have any type of underlying cardiovascular complications is unconvincing. The fact that millions have used ephedrine with no apparent problem underscores the notion of relative safety.
Other reports and studies also point to the safety of mahaung or ephedrine when used in rational doses. For example, a study of ephedrine use in obese teenagers, average age 16, found that ephedrine and caffeine in combination with a diet that reduced calories by 500 a day led to safe fat loss with negligible side effects.1
Perhaps in response to the FDA-commissioned report, a group representing supplement manufacturers commissioned its own safety review of ephedrine, which was released in late December. The Council for Responsible Nutrition contracted with Cantox, an independent consulting firm, to analyze previously existing studies about the safety of using ephedrine for weight-loss purposes. The researchers reviewed 19 studies, including a recent study jointly conducted by Harvard and Columbia University researchers that examined adverse effects of ephedrine in detail.
Those effects include a transient increase in blood pressure and an increase in heart rate of four beats per minute that was sustained throughout the study. That’s an expected finding, since ephedrine functions as both a beta-1 and beta-2 adrenal agonist. The beta-1 properties make it act similar to epinephrine, which stimulates the heart, which accounts for the slightly raised heart rate and blood pressure readings. The Columbia and Harvard researchers found no evidence of any effect of ephedrine on cardiac irritability. Weight loss was also significant among ephedrine users.
Based on those findings, the supplement group stated that it believes ephedrine is safe and effective for weight loss at a total dose of 90 milligrams a day. It also noted that FDA reports of adverse effects, such as those described above, were flawed due to incomplete data or were based on ephedrine taken in combination with other substances or at an abusive dosage.
The supplement group also reiterated the definite contraindications for ephedrine use, which include the following: presence of coronary thrombosis, heart disease, diabetes, glaucoma, hypertension, thyroid disease, impaired cerebral circulation, adrenal tumors, kidney impairment and enlarged prostate. For anyone who does not have any of those conditions, the group feels that ephedrine is safe. The sheer number of people who use it uneventfully appears to bolster that contention.
Thyroid: a Legitimate Fat-Loss Drug?
The recent advent of various active thyroid hormone precursors available for over-the-counter sales has once again fueled the longstanding debate concerning the effectiveness of using thyroid drugs and related substances as a way to promote greater fat loss. The new supplemental forms of thyroid are not direct thyroid hormone drugs, such as Synthroid (T4) and Cytomel (T3), but are instead thyroid metabolites or have not been sold as drugs yet.
One example of a nonprescription thyroid substance is called triac, also known as tiratricol, or triiodothyroacetic acid. It first appeared in drug form years ago under the trade name Triacana. About 25 years ago bodybuilders experimented with Triacana after being told by a well-known French champion that it enabled him to get cut without the muscle loss brought on by other thyroid drugs. His statement didn’t ring true, however, since several of the bodybuilders who used Triacana claimed it either caused too many side effects (similar to straight thyroid drugs) or caused them to lose muscle.
Triac resurfaced for over-the-counter sales when it was found to fall in the gray area created by the 1994 Food Supplement Act. In effect, since triac exists in some foods and is a naturally occurring substance, the government had to prove it toxic or allow it to be sold. After it has been on the market for about a year, several cases of triac-induced toxicity were reported to the FDA, prompting the federal agency to remove it from commercial sales. One distributor of triac (which was sold under a different, proprietary name) still claims that it’s a relatively nontoxic substance if used according to directions.
The latest over-the-counter supplemental thyroid has genuine thyroid activity, particularly in muscle. It’s called T2, with the 2 referring to the number of iodine atoms it contains. In contrast, the two major thyroid hormones produced in the body are T4 and T3, with T3 being the most active form. Thus, T2 is a sort of intermediate form of the major thyroid hormones, but it has true metabolic activity in that it increases resting metabolic rate, just as drug forms of thyroid hormone do.
Nevertheless the question remains: Do thyroid hormones or intermediates have a legitimate place in bodyfat-control techniques? The use of thyroid hormones for promoting fat loss is nothing new. Forms of thyroid were used for that purpose as far back as 1895, and various forms of thyroid hormones have been popular since that time. For example, in the 1940s desiccated thyroid, thyroglobulin and thyroid colloid protein were all popular. In the ’50s they were often combined with diuretic drugs, and in the ’60s they were used with amphetamines.
The products weren’t standardized, however, and one tablet could contain more active hormone than the next. The introduction of standardized thyroid drugs, first Synthroid and later Cytomel, eliminated the inconsistencies.
Physicians are loathe to prescribe thyroid drugs for weight-loss purposes for a number of reasons. The main reason relates to side effects, such as increased cardiovascular stress. Another is that many obese people, when tested for thyroid activity, not only show up as normal, but in many cases show elevated resting metabolisms. Among the factors that determine resting metabolic rate is the amount of lean mass, and many obese people also have a good amount of muscle under their fat, which accounts for their elevated resting metabolic rates.
Excessive eating also stimulates the sympathetic nervous system (SNS), which interacts with thyroid in elevating the resting metabolic rate. With activation of the SNS, enzymes that convert T4 into T3 and T2 are also activated, which increases thyroid activity and basal metabolic rate. The primary hormone of the SNS is norepinephrine, and studies show that when either norepinephrine or T3 is provided, thermogenic processes increase twofold, When both hormones are provided simultaneously, thermogenesis rises 20-fold.
Thermogenesis involves the conversion of fat calories into heat. The thermogenesis induced by thyroid is related to the control by thyroid hormones of special uncoupling proteins found in fat, internal organs and muscle. The main uncoupling protein in humans is UCP-3, which decreases threefold under low thyroid conditions but increases sixfold under conditions of elevated thyroid activity (hyperthyroidism). UCP-3 levels, besides being controlled by thyroid hormone, are also influenced by overfeeding, leptin, beta-3 agonist drugs and dietary fat.
Obesity is often associated with a defective uncoupling, or thermogenic process, and even though blood tests show obese people as having normal thyroid function as measured by T4, their T3 levels may still be below par (euthyroid sick syndrome), leading to defective thermogenesis. As a result, the enzymes needed to convert T4 into the more active T3 don’t work at full capacity in certain organs or tissues.
Since thyroid hormone corrects such problems, it appears that thyroid may have a place in a weight-loss regimen. In fact, some studies show that using thyroid may offset the drop in resting metabolism that occurs with most reduced-calorie diets. The problem is that early studies involving thyroid hormone and fat loss used far too a high a dose while ignoring or not being aware of the necessity of making certain diet alterations while using thyroid drugs. Consequently, the subjects lost muscle. A typical finding was that the weight loss induced by thyroid consisted of 75 percent fat and 25 percent muscle’too much lean tissue to lose.
More recent studies show that using T3 doesn’t appear to cause as much muscle loss as was previously thought. Small doses of T3 may offset the drop in resting metabolism that occurs during dieting without a concomitant loss of muscle. That’s particularly true if a weight-loss diet emphasizes high-quality protein sources, such as chicken, beef, fish, eggs and a solid milk-protein supplement.
Ensuring the intake of other nutrients will also promote optimal thyroid activity. For example, the deiodinase enzyme activity needed to convert T4 into T3 requires the minerals zinc and selenium. Studies show that supplying adequate zinc prevents the decline in deiodinase activity by 67 percent under dieting conditions, while selenium prevents the drop in activity by 47 percent.
If you take in less than 40 grams of carbohydrate a day, your body will convert active thyroid (T3) into an inactive version (reverse T3) as a means of sparing the loss of vital tissue. Using thyroid can deplete muscles of potassium and bones of calcium, both of which should be supplemented when you’re using any type of thyroid hormone.
Anyone contemplating using supplemental thyroid for fat loss should watch for signs of hyperthyroidism, including a rapid heartbeat, nervousness, restlessness, feeling hot all the time and insomnia. Any loss of muscle is also a definite no-no. Rather than resorting to prescription drugs, use one of the available T2 forms sold over the counter. It should work well for fat-loss purposes when combined with a proper diet and exercise regimen.
1 Molnar, D., et al. (2000). Safety and efficacy of treatment with an ephedrine/caffeine mixture. The first double-blind placebo-controlled pilot study in adolescents. Int J Obesity. 24:1573-1578. IM