One reduces energy intake, the other increases energy expenditure

When you start thinking about getting a wider bathroom mirror, you know you’re in trouble—especially if the present one goes wall-to-wall. And when the Post Office says it’s going to give you your own ZIP code, that does it. You stamp your foot, call a contractor to repair the hole you just made in the floor, and vow that you’re going to dosomething about all that flab. You want to be slim, sure, but how are you going to accomplish that? Well, duh—by losing weight, of course.

Americans have been losing a lot of weight lately. Unfortunately, most of it has been from their wallets. Compared to the weight-loss industry, there is probably no enterprise, with the possible exception of government, that promises so much to so many, yet delivers so little to so few—while raking in piles of money for consistently achieving near-total failure. You’ve probably heard it all before: diets don’t work, any weight loss won’t last, some diets are bogus, others are harmful, the “guarantees” are worthless, the promoters are crooks, etc. (Now you’ve heard it all again—sorry.)

The sad thing is, much of that is true. And despite our collective obsession with weight loss, we have become the earth’s fattest, least-fit people—including our kids—and it’s getting worse all the time. That’s great news for the weight-loss hucksters, whose skill at separating people from their money must make politicians green with envy, because these people fork it over willingly! (P. T. Barnum was right.)

Supplements Can Help with Weight Loss

Since the laws of physics have not been repealed lately, it bears repeating that there are only two ways to lose weight: (1) reduce energy intake (consume fewer calories), and (2) increase energy expenditure (burn more calories). Simple, no? Simple, not—it’s very hard for most people to do. It’s for the strong of heart and mind. It takes willpower and self-discipline, without which your chances of losing weight are about the same as those of Congress being seized by a sudden attack of ethical behavior.

Fortunately, though, the laws of chemistry haven’t been repealed either, and there are ways in which your willpower and self-disciplined efforts to take in fewer calories and burn off more calories can be augmented by the reactions of certain nutritional supplements. Let’s look at two of them: 5-HTP, which helps reduce energy intake, andEGCG (from green tea), which helps increase energy expenditure.

5-HTP Suppresses Appetite

In the human body, the amino acid 5-HTP (5-hydroxytryptophan) is the immediate precursor to one of the brain’s most important neurotransmitters, serotonin. Serotonin helps to regulate mood, sleep, and appetite, among other things. In cases of serotonin deficiency (which can arise in different ways), there is a tendency to become depressed, to sleep poorly, and to overeat. It is believed, e.g., that genetically induced serotonin deficiency is a common factor in obesity, and there is no doubt that this compound has a major influence on eating behavior.1

It almost goes without saying that when you have a deficiency of some substance, you should try to correct it by supplementing with that very substance—or, in some cases, with a precursor substance, which is sometimes more desirable. To correct serotonin deficiency, it’s preferable to take not serotonin itself, but 5-HTP.* Your body converts much of it to serotonin, which is found not only in the brain but also in relatively high concentrations in blood platelets and in the intestinal wall. (Serotonin is a powerful stimulant of smooth muscle and may play a role in promoting intestinal peristalsis.) By boosting brain serotonin levels, 5-HTP helps create a feeling of satiety (fullness), thus suppressing appetite. Hence, energy intake is reduced (weight-loss key #1).

*Although it occurs naturally in the human body, 5-HTP is obtained for use as a supplement from the seeds of an African plant,Griffonia simplicifolia. It is the identical molecule.

5-HTP Reduces Caloric Intake

Most of the clinical studies on the use of 5-HTP for weight loss were done by a group of Italian researchers at the University of Rome in the early 1990s. In one such study on 19 obese women (a 5-week, double-blind, crossover trial in which each woman served as her own control), 79% of the women reported a decrease in appetite while taking 5-HTP.2 This was borne out by measurements of their actual caloric intake: it was found that supplementation with 5-HTP reduced the women’s daily intake by 508 calories—a 22% reduction compared with placebo. Over the 5-week period, the women lost an average of 3.1 lb with 5-HTP, vs. 0.9 lb with placebo. The amount of 5-HTP used daily (taken in three divided servings) was 3.6 mg per pound of body weight; this corresponds to a total of 450 mg per day for a 125-lb woman, or 900 mg per day for a 250-lb woman.

5-HTP Produces Weight Loss, Diet or Not

In a second study, the Italian researchers put 14 obese women on a 1200-calorie/day diet for 6 weeks.3 Some were given 300 mg of 5-HTP 30 minutes before meals (a total of 900 mg per day), while the others were given placebo. Over the 6-week period, the women taking 5-HTP lost 6.8 lb, on average, compared with 1.5 lb for the women on placebo.

In the same study, the researchers had previously tested the same women during a 6-week period in which they were given the same daily 5-HTP (or placebo) regimen, but without any dietary restrictions. Over that 6-week period, the average weight loss was less (not surprisingly), but still appreciable: 3.5 lb with 5-HTP and 1.1 lb with placebo. Thus, with or without dietary restrictions, the women in this study lost substantial amounts of weight (10.3 lb total) while taking 5-HTP—4 times as much as with placebo (2.6 lb total).

5-Fold Greater Weight Loss with 5-HTP

In yet a third study, of essentially the same design as the one just discussed, but with 20 obese women, the Italian researchers found that 300 mg of 5-HTP taken 30 minutes before meals resulted in a 6-week weight loss of 7.3 lb with 5-HTP vs. 1.8 lb with placebo when the women were on the restrictive 1200-calorie/day diet.4 Without the diet, the women had 6-week weight losses of 3.7 lb and 0.6 lb, respectively. Thus, the total weight losses over the 12-week period of this study were 11 lb with 5-HTP and 2.4 lb with placebo—a nearly 5-fold difference. The 11-lb weight loss represented 5% of the women’s starting weight of 220 lb.

“. . . oral administration of the 
green tea extract stimulated 
thermogenesis and fat oxidation 
and thus has the potential to 
influence body weight and 
body composition . . . .”

In this third study, 5-HTP also produced dramatic results in terms of the women’s feelings of early satiety, i.e., feeling full earlier than usual during a meal. When the women were not on the restrictive diet, 100% of those who were taking 5-HTP reported early satiety. Even when they were on the diet, however (but taking 5-HTP), this feeling persisted: the figure then was a remarkable 90%. Clearly, the feeling of early satiety led the women to eat less than usual, resulting in the weight losses observed.

Slow Buildup Is Best with 5-HTP

In the studies discussed above, about two-thirds of the women reported mild nausea while taking these very large doses (up to 900 mg/day) of 5-HTP; in the second and third studies, nausea occurred during the first 6 weeks but not during the second 6 weeks. In real life, the easy way to avoid nausea caused by 5-HTP is to start with a small amount and build it up gradually over a period of 2 weeks; this is sufficient time to allow the body to adjust, and thereafter the supplement is well tolerated.5

EGCG Is Green Tea’s Crown Jewel

For a number of reasons, the compound EGCG (epigallocatechin gallate) is shaping up to be one of the most valuable nutritional supplements known to science. There is growing evidence of its potent protective effects against cancer, heart disease, diabetes, microbial infections, and possibly Parkinson’s disease. And all that from ordinary green tea!

EGCG belongs to the family of chemical compounds called catechins, which are a subclass of the polyphenols, compounds well known for their antioxidant properties. Of the various catechins in green tea, EGCG is by far the most pharmacologically active and, by a stroke of luck, also the most prevalent, accounting for at least half the total polyphenol content of green tea.*

*Why does it have to be green tea? Because in the oxidative fermentation process used to make the other two basic kinds of tea, oolong and black, the EGCG and related beneficial compounds are largely destroyed. Green tea is not fermented, so the catechins remain unscathed. (All three teas are made from leaves of the same plant, Camellia sinensis.)

EGCG Sparks Thermogenesis

Many of the remarkable health benefits attributed to EGCG are believed to be due to its powerful antioxidant activity, but there is clearly more to it than that. As if the benefits listed above weren’t enough, EGCG is also an effective stimulator of thermogenesis, a process that is central to weight loss.

Thermogenesis is the generation of heat by physiological processes. In our bodies, it occurs in part through a series of chemical reactions in which fat molecules are “burned” to form carbon dioxide and water. These reactions liberate thermal energy (heat), which, along with the carbon dioxide and water, is tangible evidence of the disappearance of those fat molecules. Thermal energy is measured in units of calories. By stimulating thermogenesis, EGCG contributes to your body’s caloric output. Hence, energy expenditure is increased (weight-loss key #2).

EGCG and Caffeine Tested

Throughout the 1990s, university researchers in Switzerland were investigating the thermogenic properties of green tea, whose star ingredient, as we have seen, is EGCG. In one study a few years ago, they recruited ten healthy young men, aged 24–26, who ranged from lean to mildly obese (8–30% body fat) and who ate a typical Western diet in which fat contributed 35–40% of their usual daily energy intake.6

On a rotating, randomized, double-blind basis at intervals of about one week, the men were given three supplement treatments for one day each. Each treatment consisted of: (1) a powdered green tea extract (in an amount roughly equivalent to four cups of the beverage per day), or (2) an amount of caffeine (which is known to be thermogenic) equal to that found naturally in the green tea extract, or (3) a placebo. The amount of green tea extract used was 375 mg of polyphenols per day, of which 270 mg (72%) was EGCG.

During the entire 5–6-week duration of the study, the men were restricted to a standard weight-maintenance diet in which the daily energy intake consisted of about 13% protein, 40% fat, and 47% carbohydrate. For each of the three one-day treatments, the men were confined for 24 hours to a respiratory chamber (the size of a small room) designed to allow precise measurement of their energy expenditure. They took the supplements in three equal doses, with breakfast, lunch, and dinner.

EGCG Burns the Fat

Compared with placebo, the green tea extract produced a significant increase in total energy expenditure: about 4%. This corresponds to a large increase in the thermogenic component of total energy expenditure: about 35–43%. The authors concluded that “. . . oral administration of the green tea extract stimulated thermogenesis and fat oxidation and thus has the potential to influence body weight and body composition . . . .” Their discovery—the first demonstration of this effect of green tea in a human trial—built upon their own previous laboratory work that led to the same conclusion.7

In the new study, the caffeine alone produced no significant increase in total energy expenditure compared with placebo, presumably because the amount given (150 mg per day) was below its threshold for stimulating thermogenesis. It may well be, however, that the green tea effect was due partly to its caffeine content, through a synergistic interaction between the caffeine and EGCG. (For more on caffeine’s synergism, see the sidebar, “Caffeine and Ephedrine Work Well Together.”)

Caffeine and Ephedrine Work Well Together

Caffeine is a central nervous system stimulant that also acts as a circulatory, respiratory, and digestive-system stimulant. A thermogenic agent in its own right, it also boosts the thermogenic properties of other such agents. Among these are EGCG, from green tea, and ephedra, a plant native to China (where it’s called ma huang) and India. Ephedra has been used for weight loss and as a general tonic for thousands of years in the Far East. The principal active compound in ephedra is ephedrine.

Caffeine and ephedrine (both are alkaloids) appear to promote weight loss by working synergistically, both in central (brain-level) suppression of appetite and in peripheral (body-wide) stimulation of thermogenesis.1 A key benefit of their combined action is that it promotes the loss of fat but not of lean muscle mass.2 The caffeine/ephedrine combination also increases athletic endurance.3

One study (actually, a reanalysis of a previous study) has shown that 2.6 times as many patients lost 44 lb or more by taking caffeine and ephedrine as by taking placebo: the success rates were 37% and 14%, respectively.4 The caffeine/ephedrine combination also helped more patients lose at least 22 lb than did placebo (89% vs. 63%), and no patient lost less than 11 lb (0% vs. 11%).


  1. Toubro S, Astrup A, Breum L, Quaade F. Safety and efficacy of long-term treatment with ephedrine, caffeine, and an ephedrine/caffeine mixture. Int J Obes Relat Metab Disord 1993;17:S69-72.
  2. Astrup A, et al. The effect of ephedrine/caffeine mixture on energy expenditure and body composition in obese women. Metabolism 1992;41:686-8.
  3. Bell DG, Jacobs I, Zamecnik J. Effects of caffeine, ephedrine and their combination on time to exhaustion during high-intensity exercise. Eur J Appl Physiol 1998;77:427-33.
  4. Vedelspang A, Astrup A, Toubro S, Breum L. Clinical effects of treatment with ephedrine/caffeine versus placebo: from mean weight loss to proportion of successful patients. Int J Obes 1997 Jun;21(Suppl 2):S52 abstract 147.

5-HTP and EGCG: Helping Hands

How fortunate we are that Mother Nature has provided two such excellent, and complementary, supplements as 5-HTP and EGCG to aid us in the eternal quest for weight loss. Are they “magic bullets,” guaranteed to do the trick? No, you still have to muster the willpower and self-discipline we spoke of earlier—those are the real magic bullets. The supplements, though, can definitely give you two helping hands in shedding those extra pounds, if you commit yourself to whatever your personal diet and exercise program may be, and stick to it. If you do, pretty soon you’ll be admiring yourself again in that bathroom mirror.


  1. Wurtman RJ, Wurtman JJ. Brain serotonin, carbohydrate-craving, obesity and depression. Adv Exp Med Biol 1996;398:35-41.
  2. Ceci F, Cangiano C, Cairella M, Cascino A, Del Ben M, Muscaritoli M, Sibilia L, Rossi-Fanelli F. The effects of oral 5-hydroxytryptophan administration on feeding behavior in obese adult female subjects. J Neural Transm1989;76(2):109-17.
  3. Cangiano C, Ceci F, Cairella M, Cascino A, Del Ben M, Laviano A, Muscaritoli M, Rossi-Fanelli F. Effects of 5-hydroxytryptophan on eating behavior and adherence to dietary prescriptions in obese adult subjects. Adv Exp Med Biol1991;294:591-3.
  4. Cangiano C, Ceci F, Cascino A, Del Ben M, Laviano A, Muscaritoli M, Antonucci F, Rossi-Fanelli F. Eating behavior and adherence to dietary prescriptions in obese adult subjects treated with 5-hydroxytryptophan. Am J Clin Nutr 1992 Nov;56(5):863-7.
  5. Murray MT. 5-HTP, The Natural Way to Overcome Depression, Obesity, and Insomnia. Bantam Books, New York, 1998.
  6. Dulloo AG, Duret C, Rohrer D, Girardier L, Mensi N, Fathi M, Chantre P, Vandermander J. Efficacy of a green tea extract rich in catechin polyphenols and caffeine in increasing 24-h energy expenditure and fat oxidation in humans. Am J Clin Nutr 1999;70:1040-5.
  7. Dulloo AG, Seydoux J, Girardier L, Chantre P, Vandermander J. Green tea and thermogenesis: interactions between catechin-polyphenols, caffeine, and sympathetic activity. Int J Obes Relat Metab Disord 2000 Feb;24(2):252-8.