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Impossible Weight-Loss Claims:
Summary of an FTC Report
Stephen Barrett, M.D.
Despite unprecedented levels of law
enforcement by the Federal Trade Commission, deceptive weight-loss
advertising is rampant. In response to the problem, the agency
has identified seven claims that, based on current scientific
knowledge, are impossible to fulfill and therefore should be
rejected by responsible advertising outlets. The agency's conclusions
have been published in a December 2003 staff report called Deception
in Weight-loss Advertising Workshop' Seizing Opportunities and
Building Partnerships to Stop Weight Loss Fraud.
Here's the FTC list plus the report's analysis of each claim.
(In a few cases, I have slightly modified the FTC's wording.)
False Claim #1. The product causes weight loss of two pounds
or more a week for a month, or more without dieting or exercise.
FTC Staff Analysis: The FTC has considerable experience
with claims that users can lose substantial weight without diet
or exercise. For example, in FTC v. SlimAmerica, the FTC
challenged claims that a product called Super Formula
(which contained chromium picolinate, hydroxycitric acid, chitin,
and glucomannan) could cause dramatic weight loss, including
as much as 49 pounds in 29 days  The court, after hearing
from experts on both sides, concluded:
To lose one pound of weight, according to a credible expert,
the average individual needs a deficit of approximately 3,500
calories between caloric intake and caloric output. Although
drugs may make it easier to achieve this deficit, they cannot
alter this basic equation. Thus, it would be impossible for a
person who did not diet or exercise to lose weight simply by
taking the defendant's drug or weight loss product. It is thus
elementary that if a person consumed calories in excess of his/her
daily needs, and did not diet or exercise there would be weight
increase, rather than decrease 
Theoretically, products purporting to cause weight loss without
diet or exercise would either need to cause malabsorption of
calories or to increase metabolism (so-called "thermogenic
agents"). The number of calories that can be malabsorbed
appears to be limited to 1200 to 1300 calories per week, or roughly
one-third of a pound per week, at best. Accordingly, malabsorption
alone is unlikely to lead to substantial weight loss 
With regard to thermogenic agents, it is often difficult to
evaluate the supporting evidence, given the lack of rigorous
methodology in many of the studies in question . In any event,
the effect of purported metabolism boosters appears to be very
limited. For example, a study of green tea extract found only
a 4% increase in metabolism . Ephedrine, usually sold in combination
with caffeine, has been one of the most popular thermogenic agents
marketed over the past five years. It appears to produce only
modest weight loss, mostly due to its appetite suppression effect
The significance of the small amount of weight that can be
lost through malabsorption or increased metabolism is debatable.
It is clear, however, that as the amount of claimed weight loss
increases, the likelihood that such weight loss can be achieved
without restricting caloric intake or increasing exercise decreases
dramatically. For example, weight loss in the range of two pounds
per week over periods of time beyond four weeks (eight or more
pounds per month) would require a net caloric deficit of 7,000
calories per week, or a 1,000 calories per day, over an extended
period of time. That would amount to 40% of the total calories
consumed per week on a 2,500 calorie per day diet . As noted
below, about 180 calories per day appears to be the outer limit
for malabsorption. In addition, the staff is unaware of any scientific
literature suggesting that 40% increases in metabolism can be
achieved without producing toxic effects on the body.
In summary, the amount of weight loss that can be achieved
through the use of nonprescription products without reducing
caloric intake or increasing exercise is likely to be no more
than one-fourth to one-third of a pound per week, with additional
weight loss being attributable to reduced caloric intake. Accordingly,
weight loss in the range of two pounds per week over periods
of time beyond four weeks (eight or more pounds per month) without
restricting caloric intake or increasing exercise is not now
scientifically feasible . (Ads that claim weight loss of less
than two pounds per week without dieting or increasing exercise
may still be false or unsubstantiated. The FTC chose the two-pounds-per-week
level solely for the purpose of establishing a performance limit
that is beyond reasonable scientific debate.)
False Claim #2. The product causes substantial weight loss,
no matter what or how much the consumer eats.
FTC Staff Analysis: This claim is largely a variation
of the claim that users can lose weight without reducing caloric
intake or increasing exercise, because the essence of the claim
is that users can lose weight without reducing caloric intake
and may even increase caloric intake and still lose weight. This
would defy the laws of physics. Accordingly, for the reasons
set forth in the discussion of Claim #1, the claim that users
can lose substantial weight while still enjoying unlimited amounts
of high calorie foods is not scientifically feasible.
False Claim #3 The product causes permanent weight loss (even
when the consumer stops using the product).
FTC Staff Analysis: Assuming that a product causes
weight loss through a reduction of calories, through either an
appetite suppression or malabsorption mechanism, weight would
be regained once the intervention stops and calorie consumption
returns to pre-intervention levels. In fact, it is well established
that most people who lose weight gain it back within five years.
Experts have repeatedly observed that although persons generally
lose weight while actively participating in treatment, they tend
to regain the weight over time once treatment ends . According
to the National Academy of Science, Food and Nutrition Board,
"Many programs and services exist to help individuals achieve
weight control. But the limited studies paint a grim picture:
those who complete weight-loss programs lose approximately 10
percent of their body weight only to regain two-thirds of it
back within 1 year and almost all of it back within 5 years."
 Finally, no long-term studies on the weight loss maintenance
of any of the covered products have been brought to the staff's
attention, and we are not aware of any such studies in the published
literature  Accordingly, a claim that a nonprescription drug,
dietary supplement, cream, wrap, device, or patch can cause permanent
weight loss is not scientifically feasible .
False Claim #4. The product blocks the absorption of fat or
calories to enable consumers to lose substantial weight.
FTC Staff Analysis: The biological facts do not support
the possibility that sufficient malabsorption of fat or calories
can occur to cause substantial weight loss. To lose even one
pound per week would require the malabsorption of about 500 calories
a day or about 55 grams of fat . To lose two pounds per day,
as stated in the sample ad, would require the malabsorption of
7000 calories per day, which is impossible given that it is several
times the total calories that most people consume on a daily
basis, let alone the number of calories consumed from just fat
. The FTC has challenged a number of deceptive fat blocker
claims for some of the most popular diet products on the market
, and the evidence supports the position that consumers cannot
lose substantial weight through the blockage of the absorption
of fat . Based on its past experience, as well as the discussion
at the workshop, written comments, and published studies, the
staff concludes that the claim that a nonprescription drug, dietary
supplement, cream, wrap, device, or patch will cause substantial
weight loss through the blockage of absorption of fat or calories
is not scientifically feasible.
False Claim #5. The advertised product enables consumers to
lose more than three pounds per week for more than four weeks.
FTC Staff Analysis: There are significant health risks
associated with medically unsupervised, rapid weight loss over
extended periods of time . This conclusion does not mean
that every person who loses more than three pounds per week will
suffer serious side effects, but it does mean that weight loss
in this range can create medical risks. In general, "the
more restrictive the diet, the greater are the risks of adverse
effects associated with weight loss."  One of the best
documented risks is the increased incidence of gallstones .
Added to this risk is the fact that a covered product could be
sold as part of a "program" that includes a very-low-calorie
diet and that very low calorie diets can be nutritionally inadequate
and result in serious injury or even death  Based on the
discussion at the workshop, written comments, and the published
literature, the claim that consumers who use one of the covered
products without medical supervision can safely lose more than
three pounds per week for a period of more than four weeks is
not scientifically feasible.
False Claim #6. The product causes substantial weight loss
for all users.
FTC Staff Analysis: Although there are common characteristics
among the relevant population, there is not just one cause of
overweight or obesity. In some people, the cause may be more
closely linked to genetic factors, while in other instances,
the principal causal factor may be environmental. Moreover, it
should be obvious that diets, metabolic rates, and levels of
physical activity vary from one individual to another and that
compliance levels will vary. Even approved drugs for weight loss
always have a high level of nonresponders, and even gastric surgery
for obesity is not successful 100 percent of the time. Thus a
claim that a nonprescription drug, dietary supplement, cream,
wrap, device, or patch will cause substantial weight loss for
all users is not scientifically feasible.
False Claim #7. The product causes substantial weight loss
by wearing it on the body or rubbing it into the skin.
FTC Staff Analysis: The products at issue for this
claim include creams, wraps, patches, earrings, shoe inserts,
and rings, among others, that can be purchased without a medical
prescription. Examples include, "Lose two to four pounds
daily with the Diet Patch," and "Thigh Cream drops
pounds and inches from your thighs." Based on the investigative
experience of FTC staff, as well as the discussion at the workshop,
written comments, and the published literature, a claim that
users can lose substantial weight though the use of the advertised
product that is worn on the body or rubbed into the skin is not
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This article was posted on December 16, 2003.
- FTC v. SlimAmerica, Inc., 77 F. Supp. 2d 1263 (S.D.
Fla. 1999). See also FTC v. Slim Down Solution, LLC, No.
03-80051-CIV-PAINE (S.D. Fla. filed Jan. 24, 2003); FTC v.
Mark Nutritionals, Inc., No. SA02CA1151EP (W.D. Tex. filed
Dec. 5, 2002); FTC v. No. 9068- 8425 Quebec, Inc. d/b/a Bio
Lab, No. 1:02:CV-1128 (N.D.N.Y. July 28, 2003) (stipulated
final judgment); National Dietary Research, 120 F.T.C.
893 (1995) (consent order); Body Wise Int'l, 120 F.T.C.
704 (1995) (consent order); Taleigh Corp., 119 F.T.C.
835 (1995) (consent order); FTC v. Shell, No. 90 0120
(Kx) (C.D. Cal. Apr. 8, 1991) (stipulated permanent injunction).
- 77 F. Supp. 2d at 1273.
- One expert on the panel referred to a 1984 study of glucomannan
that reported weight loss of 5.5 pounds over 8 weeks without
any changes in diet or physical activity. Walsh, D.E., et
al., Effect of Glucomannan on Obese Patients: A Clinical
Study, 8 International Journal of Obesity 289-93 (1984).
In this study, patients were instructed not to deviate from their
previously established eating and exercise patterns. This study
is not particularly persuasive given the small number of subjects
in the treatment group (10) and the fact that subjects did not
maintain appropriate food diaries. There is no way to be sure
that subjects did not change eating patterns. In fact, one of
glucomannan's purported mechanisms of action is as a bulking
agent, and the authors note it "added bulk in the stomach
just before each meal, [which] may decrease the appetite and
[cause subjects] to eat less at each meal." Id. at
- See generally Allison, D.B., et al., Alternative
Treatments for Weight Loss: A Critical Review, 41 Critical
Reviews in Food Science and Nutrition 1, 2-3, 18-20 (2001). One
common problem in studies cited to support claims of weight loss
without reducing caloric intake is the lack of any monitoring
of caloric intake in those studies. See, e.g.,
Walsh (cited in note 4).
- See Dulloo, A.G. et al., Efficacy of a green
tea extract rich in catechin polyphenols and caffeine in increasing
24-h energy expenditure and fat oxidation in humans, 70 Am
J Clin Nutr 1040-45 (1999) (comparing 24 hour energy expenditure
in subjects given either caffeine, green tea extract (including
caffeine), or placebo); see also Green Tea for Weight Loss?,
Tufts Univ. Health & Nutrition Letter, June 2003, at 3, quoting
Jeffrey Blumberg, PhD: "It can't be concluded that [the]
small increase in metabolism" reported in studies on green
tea, "'that could easily be undone by eating a single cookie
or a handful of chips,'" could lead to weight loss.
- A recently released analysis indicates that there is scientific
support that supplements containing ephedra and caffeine-containing
herbs or ephedrine plus caffeine may cause weight loss of about
1/2 pound per week over four to six months. Evidence Report/Technology
Assessment, Number 76, Ephedra and Ephedrine for Weight
Loss and Athletic Performance Enhancement: Clinical Efficacy
and Side Effects, U.S. Department of Health and Human Services,
Agency for Healthcare Research and Quality, Feb. 28, 2003, at
219. It is not entirely clear how much of this modest effect
is due to increased metabolism and how much is due to appetite
suppression, but it has been estimated that at least half of
the effect is due to appetite suppression. See Tr. at
90 (Anthony Almada and Dr. Steven Heymsfield). Some ephedrine
studies have reported a 10% increase in metabolic rate. See
Greenway, F.L., The safety and efficacy of pharmaceutical
and herbal caffeine and ephedrine use as a weight loss agent,
The International Association of the Study of Obesity, 2 Obesity
Reviews 3:199-211, 202 (2001). In any event, the effect, if any,
without also reducing caloric intake would appear to be quite
limited. For example, one ephedrine and caffeine study found
that 75 percent of the weight loss was explained by anorexia
and 25 percent by increased thermogenesis. See id. at
- American men and women consume, on average, about 2800 and
1800 calories per day, respectively, but there are large variations
based on body size and other factors. Kathleen Melanson and Johanna
Dwyer, Popular Diets for Treatment of Overweight and Obesity,
in Handbook of Obesity Treatment 250 (Thomas A. Wadden
and Albert J. Stunkard eds., New York: The Guilford Press, 2002).
- The specification of two pounds in this claim is conservative.
The scientific literature does contain reports of studies that
claim to have tested certain ingredients without diet or exercise.
Two pounds of weight loss per week over a period of four weeks
(eight pounds per month), however, significantly exceeds the
results reported in these studies and would still include the
most obviously exaggerated claims. It also would take into account
temporary fluid loss during the initial week to 10 days. It should
be emphasized, however, that ads that claim weight loss of less
than two pounds per week without dieting or increasing exercise
may still be false or unsubstantiated. The two pounds per week
level is used here solely for the purpose of establishing a performance
limit that is beyond reasonable scientific debate.
for Voluntary Weight Loss and Control, NIH Technol. Assess.
Conf. 1992 Mar. 30-Apr. 1; 10.
- Thomas, P.R., ed., Weighing the Options: Criteria for
Evaluating Weight-Management Programs 1 (National Academy
- The FTC has challenged weight loss maintenance/permanent
weight loss claims as deceptive in a number of cases, including
most recently, FTC v. USA Pharmacal Sales, Inc., No. 8:03-CV-
1366-T-23-EAJ (M.D. Fla. July 2, 2003) (stipulated final judgment),
FTC v. Mark Nutritionals, Inc., No. SA02CA1151EP (W.D.
Tex. filed Dec. 5, 2002), and FTC v. No. 9068-8425 Quebec,
Inc. d/b/a Bio Lab, No. 1:02:CV-1128 (N.D.N.Y. July 28, 2003)
(stipulated final judgment).
- It may not be possible to determine without further investigation
whether a more explicit claim that users can maintain weight
loss as long as they continue using a particular product is false
or unsubstantiated. Therefore, this type of claim cannot be rejected
on its face as not being scientifically feasible. Nonetheless,
it could still be deceptive depending on the substantiation for
the specific product.
- Even prescription drugs do not produce such dramatic results.
For example, orlistat (XenicalTM) is an extensively studied pharmacological
agent that produces malabsorption of approximately one-third
of dietary fat in a meal. Louis J. Aronne, Treatment of Obesity
in the Primary Care Setting, in Handbook of Obesity Treatment
390 (Thomas A. Wadden and Albert J. Stunkard eds., New York:
The Guilford Press, 2002); see also George A. Bray, Drug
Treatment of Obesity, in Handbook of Obesity Treatment
327 (Thomas A. Wadden and Albert J. Stunkard eds., New York:
The Guilford Press, 2002) (discussion of orlistat response to
treatment rates). Beyond this amount, users experience significant
gastrointestinal disturbance, including loose stool and diarrhea.
See Bray at 328-29; Aronne at 390. On a 60 grams of fat
per day diet, approximately 180 calories per day would not be
absorbed, resulting in weight loss of approximately onethird
of a pound per week. By itself, this amount of weight loss would
not be substantial, as that term is used here. See Tr.
at 60-61, 62, 66, and 67. The evidence of significant weight
loss achieved through agents such as orlistat is based on use
of the agent in combination with a restricted calorie diet. For
example, used in combination with a low calorie diet, orlistat
has been reported to result in an 8% weight loss after a year
compared with 4% in a control group. The control group was also
on a low calorie diet. See Aronne at 390. Thus, the weight
loss is not attributable to blocking the absorption of fat alone.
- Tr. at 60 (Dr. Judith Stern). Seven thousand calories represents
approximately 750 grams of fat daily. On a 2,500 calorie per
day diet consisting of 40% fat, a person would consume only about
110 grams of fat.
- See, e.g, FTC v. Enforma Natural Prods., Inc., No.
00-4376JSL (Cwx) (C.D. Cal. Apr. 25, 2000) (stipulated final
judgment) ($10 million in consumer redress); FTC v. Slim Down
Solution, LLC, No. 03-80051-CIV-PAINE (S.D. Fla. filed Jan.
24, 2003); FTC v. KCD Inc., 123 F.T.C. 1535 (1997) (consent
- See Gades, M.D. and Stern, J.S., Chitosan Supplementation
and Fecal Fat Excretion in Men, 11 Obesity Research 683-88
(May 2003); Gades, M.D. and Stern, J.S., Chitosan supplementation
does not affect fat absorption in healthy males fed a high-fat
diet, a pilot study, 26 International Journal of Obesity
119-133 (2002); Pittler, M.H., et al., Randomized,
double-blind trial of chitosan for body weight reduction,
53 European Journal of Clinical Nutrition, 379- 81 (1999); Wuolijoki,
E., et al., Decrease in Serum LDL Cholesterol with
Microcrystalline Chitosan, 21 Methods Find. Exp. Clin. Pharacol.,
357-61 (1999); and Ho, S.C., et al., In 44 the
Absence of Dietary Surveillance, Chitosan does not Reduce Plasma
Lipids or Obesity in Hypercholesterolaemic Obese Asian Subjects,
42 Singapore Med J, 1: 6-10 (2001).
- Weighing the Options at 115-17 (cited in note 11);
Edward W. Gregg and David F. Williamson, The Relationship
of Intentional Weight Loss to Disease Incidence and Mortality,
in Handbook of Obesity Treatment 126-27 (Thomas A. Wadden
and Albert J. Stunkard eds., New York: The Guilford Press, 2002).
The indication of four weeks is made here to distinguish short
term, e.g., weekend, crash diets.
- Wadden, T.A., et al., "The Cambridge Diet: More
Mayhem?" 250 JAMA 2833 (1983).