A number of my students in CFB/PHY 3333  decided to write research papers about the hCG Diet. I was particularly interested in their papers because an acquaintance of mine told me last year that they had decided to try the diet. At the time, I did not know what it was and thought little of it. After reading the research papers my students produced, I became more worried.
The hCG Diet was invented by an endocrinologist named Albert T. Simeons . He combined a 500-calorie restricted diet with the Human Chorionic Gonadotropin hormone. The claim is that the hormone negates the feelings of hunger induced by a dangerously low calorie diet, while also forcing the body to burn stored fat instead of protein for energy.
A number of studies have been done to assess the claim. Some of those studies claimed that the diet worked, and others find no benefit of combining hCG and a 500-calorie diet over using a placebo and the same 500-calorie diet . How do we decide who is right? One group of authors did a “meta-analysis”  of these publications and assessed scores to the studies based on the quality of the research (e.g. was a given study randomized-controlled or not?). They set in advance a score of 50 (out of 100) as the cutoff for higher-quality analyses. They found that of the 14 studies that scored above 50 (all of which included randomly controlled trials), 1 of the 14 found confirming evidence supporting the claims of the hCG diet. The others all found disconfirming evidence. The weight of reliable, scientific evidence is strongly against the effectiveness of the hCG diet.
From this we can conclude the following:
- Any doctor that prescribes the hCG diet is not making a decision using evidence-based medicine. Medicine without evidence supporting its claims is quack medicine. The doctor is, at the very least, not keeping up with the research in their own field and at worst is willfully ignoring evidence.
But it gets worse. The Food and Drug Administration has strong words  regarding the sale of hCG as a diet supplement:
The Food and Drug Administration (FDA) is advising consumers to steer clear of these “homeopathic” human chorionic gonadotropin (HCG) weight-loss products. They are sold in the form of oral drops, pellets and sprays and can be found online and in some retail stores. 
FDA and the Federal Trade Commission (FTC) have issued seven letters to companies warning them that they are selling illegal homeopathic HCG weight-loss drugs that have not been approved by FDA, and that make unsupported claims. 
Not only is the hCG diet not science-based medicine – selling hCG products for the purpose of the diet is ILLEGAL. What about physicians that prescribe them? According to a news report by local Dallas WFAA ,
HCG is FDA-approved for fertility treatments — not weight loss. Doctors, however, can prescribe HCG legally for an “off-label” use. 
So it’s currently legally okay for a doctor to use hCG in a way not intended, which is ethically murky. (Note: the above article claims that the “science is unclear” about the benefits of hCG, but this is likely because if you just count the number of studies there are equally many that find and don’t find benefits. WFAA was ill-equipped to understand good experiments and bad experiments, and likely misunderstood completely that the weight of reliable evidence is AGAINST the benefits of hCG).
From this, we can conclude that any doctor who prescribes this is practicing unethical quack medicine. It might not be illegal to use hCG for a purpose not intended, but it flies in the face of evidence-based medicine. Evidence-based medicine is the only reliable kind of medicine. Everything else is wishful thinking or lies.
I tried to explain to my acquaintance that hCG has been clearly shown to be no more effective than placebo. I also tried to explain that the FDA has warned companies selling hCG for weight loss that they are conducting an illegal activity. However, they were adamant. They had lost weight (they were on it three times in the last year, gaining weight back after each time), they had heard anecdotes that said it worked, and that they had their beliefs and that science had its beliefs. Pretty much the spectrum of denial. This acquaintance of mine is a very bright person, so it pained me to know that they couldn’t be convinced of the evidence. They were actually willing to pay for the placebo effect (and said as much).
As a scientist, it’s hard to listen to that.
 Published studies of hCG and weight loss:
CARNE S. The action of chorionic gonadotrophin in the obese. Lancet. 1961 Dec 9;2(7215):1282–1284.
LEBON P. Treatment of overweight patients with chorionic gonadotropin. J Am Geriatr Soc. 1961 Nov;9:998–1002.
Stein MR, Julis RE, Peck CC, Hinshaw W, Sawicki JE, Deller JJ., Jr Ineffectiveness of human chorionic gonadotropin in weight reduction: a double-blind study. Am J Clin Nutr. 1976 Sep;29(9):940–948.
Young RL, Fuchs RJ, Woltjen MJ. Chorionic gonadotropin in weight control. A double-blind crossover study. JAMA. 1976 Nov 29;236(22):2495–2497.
Shetty KR, Kalkhoff RK. Human chorionic gonadotropin (HCG) treatment of obesity. Arch Intern Med. 1977 Feb;137(2):151–155.
Greenway FL, Bray GA. Human chorionic gonadotropin (HCG) in the treatment of obesity: a critical assessment of the Simeons method. West J Med. 1977 Dec;127(6):461–463. [PMC free article]
Asher WL, Harper HW. Effect of human chorionic gonadotrophin on weight loss, hunger, and feeling of well-being. Am J Clin Nutr. 1973 Feb;26(2):211–218.
CRAIG LS, RAY RE, WAXLER SH, MADIGAN H. Chorionic gonadotropin in the treatment of obese women. Am J Clin Nutr. 1963 Mar;12:230–234.
Miller R, Schneiderman LJ. A clinical study of the use of human chorionic gonadotrophin in weight reduction. J Fam Pract. 1977 Mar;4(3):445–448.
FRANK BW. THE USE OF CHORIONIC GONADOTROPIN HORMONE IN THE TREATMENT OF OBESITY. A DOUBLE-BLIND STUDY. Am J Clin Nutr. 1964 Mar;14:133–136.
SOHAR E. A forty-day-550 calorie diet in the treatment of obese outpatients. Am J Clin Nutr. 1959 Sep–Oct;7:514–518.
HASTRUP B, NIELSEN B, SKOUBY AP. Chorionic gonadotropin and the treatment of obesity. Acta Med Scand. 1960 Sep 21;168:25–27.
Veilleux H, Fortin Z. Effets gonadiques et extragonadiques, chez l’humain, de 3500 U.I. de HCG (gonadotrophine chorionique humaine) en doses fractionnées. Vie Med Can Fr. 1972 Sep;1(9):862–871.
Gusman HA. Chorionic gonadotropin in obesity. Further clinical observations. Am J Clin Nutr. 1969 Jun;22(6):686–695.
SIMEONS AT. CHORIONIC GONADOTROPHIN IN THE TREATMENT OF OBESITY. Am J Clin Nutr. 1964 Sep;15:188–190.
HARRIS JM, WARSAW E. OBESITY: A PROBLEM WITH MANY FACETS: OBSERVATIONS ON TREATMENT WITH CHORIONIC GONADOTROPIN AS AN ADJUNCT TO DIETARY MEASURES. J Am Geriatr Soc. 1964 Oct;12:987–995.
 Lijesen GK, Theeuwen I, Assendelft WJ, Van Der Wal G (September 1995). “The effect of human chorionic gonadotropin (HCG) in the treatment of obesity by means of the Simeons therapy: a criteria-based meta-analysis”. Br J Clin Pharmacol 40 (3): 237–43. PMC 1365103.PMID 8527285