In his “Special Communication,” entitled “A
Critique of the Rationale for Cancer Treatment With Coffee Enemas and Diet,”
JAMA 268(22):3224-27, Dec. 9, 1992, Dr. Saul Green failed to
differentiate between the outdated theories of the developer, claims of past and
current proponents, and published results of current investigators. In
attempting a comprehensive critique of a long-established alternative method of
cancer management, Dr. Green encountered subject matter well beyond his
expertise. Dr. Green’s knowledge of the current literature was inadequate to
discuss both the role of coffee enemas in treatment of cancer pain, and recently
discovered mechanisms of liver transport and bile secretion. His critique, which
is riddled with omissions and citation errors, will confuse more readers than it
Because quite a few of Dr. Green’s criticisms focused on theoretical
considerations offered thirty-five years ago by Dr. Max Gerson, we feel that it
is unnecessary to defend against them. For example, Dr. Green found flaw in
Gerson’s 1958 endorsement of the cancer generalization of two-time Nobel
Laureate Otto Warburg (1883-1970). Warburg was immensely authoritative in his
time, holding the unquestioning respect of most of the world’s scientists.
Warburg won his Nobel prizes for describing the oxygen and hydrogen shuttling
enzyme systems of mitochondrial respiration. Because Warburg was able,
experimentally, to initiate malignancy by reducing oxygen supplies to fetal
sheep cells in vitro, and because of high lactic acid output by malignant cells,
he became convinced that malignancy must be a state of anaerobic (fermentation)
metabolism, which he likened to that of lower life forms.1
The Warburg generalization, which understandably persisted for many years, has
since been disproven.2
But Dr. Green was wrong to claim that the current investigators adhere to
Warburg’s cancer generalization. One of us (Hildenbrand) has clearly
disassociated himself from Warburg’s ideas about cancer: “Otto Warburg
advanced a theory of cancer which held that cancer was a fermentative disease.
The Warburg generalization is probably not correct, although the observations
that led Warburg to the generalization are most likely correct.”3
Dr. Green’s assertion, “they claim that cancer can be cured if the
patient’s body is detoxified (by the coffee enemas) and if the patient adheres
strictly to the specific diet prescribed” is nowhere to be found on any of
the pages that he has referenced to support it.4 A careful
reading of those same pages, cited again by Dr. Green as pertaining to the
materials and methods of Gerson’s treatment, will lead readers up a blind alley.
Dr. Green completely missed Gerson’s emphasis on the treatment of cancer pain
with coffee enemas, an emphasis taken up and continued by us. Dr. Green
neglected to cite or mention the content of a recent article by British
oncologists5 in which the authors described their
evaluation of patients at the Gerson therapy hospital of Mexico:
“Particularly intriguing were the low pain scores and analgesic requirements for
all the patients, despite the presence of extensive metastatic disease in many
and the fact that several had been on opioid medication previously.” This
same article was reprinted in Healing 6(3-4):21-24, 1990, which specific
issue was cited five times by Dr. Green in his article. The authors of a US.
Government report cited by Dr. Green6 summarized the
British report: “The investigators noted particularly that none of the
patients was taking opiates for pain, though several had taken them previously,
and they had low ‘pain’ scores.”
Further in this regard, one of us (Lechner) has for several years now been
conducting a prospective trial comparing the need for pain medications in cancer
patients who adhere to a modified “Gerson diet” and take coffee enemas (Group
A), and those who do not (Group B). We will relate the preliminary results of
that trial immediately after we point out several additional errors and
omissions on the part of Dr. Green.
Dr. Green wrote that patients are required by us to adhere, for life, to a
diet of juices prepared from raw fruits, vegetables, and calves liver. Nowhere
in our literature can one find evidence for these claims. Gerson’s treatment was
not lifelong, and was not built around a liquid diet. Normal beverages such as
alcohol, soda, and coffee were simply replaced by Gerson with hourly raw
vegetable juices, which were given in addition to three full meals and snacks
daily. Importantly, modern practitioners of Gerson’s treatment have long since
discontinued the use of raw veal liver. As early as 1987,7
the US. Office of Technology Assessment (OTA) was made aware that raw liver
juice therapy had been discontinued: “According to an unpublished interim
report, Peter Lechner, M.D., of the Second Department of Surgery of the
Landeskrankenhaus in Graz, Austria, is conducting a study using a modified
Gerson regimen as an adjunctive treatment. The modified regimen is described as
a high fiber, low sodium, high iodine and potassium, lactovegetarian diet with
regular coffee enemas. It reportedly omits certain elements of the original
Gerson regimen, such as liver juice, thyroid supplements (unless the patient is
hypothyroid), and niacin supplements.”6 Regarding
Gerson’s therapy as offered by the Mexican practice, OTA also noted: “The
clinic discontinued the use of raw liver juice in late 1989 because of potential
problems with infection.”6 In 1990, a third appendix
was added to the 5th edition of Gerson’s A Cancer Therapy: Results of Fifty
Cases to explain discontinuance of liver juice and to specifically warn of
campylobacter contamination; and this same warning was published by the Gerson
Institute in its membership organ.8
Dr. Green expressed general dissatisfaction with medical practices surviving
from antiquity, in particular enemas. Such practices, he argued, were based on a
primitive “knowledge of the cause of cancer.” However, temperance
dictates that the practices themselves must be evaluated appropriately, with all
the benefits of modern science, before any pronouncements can be made regarding
their utility. Even leaching, once scorned, has found a legitimate, if perhaps
temporary, niche in modern medicine.
In answer to Dr. Green’s assertion that we “are in effect endorsing the
concept of purging,” we apologize that neither of us is a student of fifth
century medicine, and we are therefore unqualified to comment. However, modern
literature suggests that Dr. Green may be overly hasty in his dismissal of
“purging,” per se, as a superstition of the past. A number of credible
contemporary authors9-14 have investigated gut lavage
(iatrogenic diarrhea) as a means of detoxifying ingested poisons, reducing
plasma endotoxins and other toxins already absorbed by the body, and increasing
gastrocolic response to feeding, among other positive findings.
Above all, Dr. Green has levied criticism at our assertion that coffee enemas, which have been observed to palliate cancer pain,5,6 may achieve this effect by stimulating detoxification through the glutathione (GSH) and glutathione-S-transferase (GST) mechanisms. Dr. Green was quite right to point out that GSH is not a precurser to bile salts. His sharp eye caught a transcription error in the published text of a taped lecture by one of us3 in which the words “bile solutes” were mistakenly typed as “bile salts.” But, it is a long leap Dr. Green takes from this specific and correct criticism to his fallacious assertion that “large-scale elimination of poisons via the bile would be an inefficient means of detoxifying the liver since any detoxified poisons in the bile could be regenerated by intestinal enzymes, reabsorbed into the bloodstream, and recirculated through the body for long periods.”
The disciplines devoted to study of hepatic transport are maturing rapidly.
Modern tracer studies directly contradict Dr. Green’s assumption regarding the
“recycling” of poisons. Goresky, et al,15 write regarding
detoxification of a drug by the liver: “A general principle has emerged. The
charged conjugates penetrate the liver cell membrane poorly in relation to the
parent drug. When a conjugate undergoing biliary excretion is formed within the
liver cell, a retarded efflux of the product to plasma is therefore found and
otherwise unexpectedly high cellular concentrations and intracellular residence
times result. The effect of the prolonged sojourn time is to amplify the
proportion of the generated metabolite excreted in bile...At an evolutionary
level, it appears that the processing of foreign materials by conjugation in the
liver is an adaptation that automatically promotes their biliary excretion.”
Modern research reveals that the liver exports glutathione into both plasma
and bile at a rate that accounts for nearly all of its biosynthesis, and that
the biliary concentration of glutathione is close to that of the liver.16
Because GSH detoxifies genotoxic electrophiles poorly by spontaneous reaction,
GST is a particularly important catalyst; their combined action leads to
Listowsky18 writes: “Glutathione-S-transferases, by
virtue of their capacities to bind and, in some cases, catalyze
biotransformations of substances such as hormones and chemicals coming from the
environment (either toxic agents or drugs), can determine whether these
compounds will function or be detoxified.” The range of GST substrates is
quite remarkable, including a large number of xenobiotics, hepatic toxins,
carcinogens, as well as endogenous prostaglandins, leukotrienes, steroids, and
organic hydroperoxides including lipid hydroperoxides and lipid peroxidation
Dr. Green noted that phenobarbital and microsomal enzyme inducers cause
increases in bile flow, “but nowhere in the scientific literature on this
subject is there a reference to the idea that coffee will do this.” We hasten to
point out that Dr. Green missed a description offered in Healing
6(3-4):38, 1990, of experiments conducted by one of us (Lechner) at the
Landeskrankenhaus of Graz, Austria, in which cafestol derived from coffee was
used to stimulate increased bile flow in rats. Instead, Dr. Green focused his
attention and comments on a paragraph preceding this description by only ten
lines of print. Had he read on, he would have known that these rat experiments
are discussed in Aktuelle Ernährungsmedizin 20
“In a small and as yet unpublished series of experiments, we were able to
achieve a significant quantitative increase of bile flow in rats, by giving them
cafestol which we produced by the method described in (Beilstein21).”
Coles and Ketterer17 write: “As more is known about
human GSH transferases, it becomes apparent that information obtained with the
rat is indeed relevant to man. The same multigene families are seen in both
species, and there is considerable identity in primary structure across the two
species.” It was with similar convictions that our coffee and rat
experiments were undertaken.
The furan moiety of cafestol diacetate is known to be a potent inducer of GST
in the rodent liver and small bowel mucosa.22 Cafestol is
one of two GST-inducing diterpene esters found in coffee.23
Coffee itself is known to induce GST, and when fed green as a food additive
could enhance GST sixfold in the liver and sevenfold in the small bowel,24
a level which is considered “quite remarkable” by the National Research
Both cafestol and kahweol have two hydroxyl groups, and will form a
diacetate, in which form they can be concentrated.
Extraction of cafestol from beverage coffee
The procedures by which we extracted cafestol from regular beverage coffee
and used it to stimulate rat bile flow are described below:
1. A coffee solution was prepared in the usual manner for Gerson patients, by
boiling in distilled water three heaping tablespoons of regular-grind,
regular-roast, commercially available coffee. The solution was strained, not
filtered. Following is a brief description of Beilstein’s21
a. Soxhlet extraction with C2H5OH
b. Distill off ether in Rotavapor = Coffee Oil
c. Addition of petroleum ether/cooling to 4C = Coffee crystals
d. Neutralization of residue with Na2SO4(5%)
e. Addition of H2O2 and C2H5OH
f. Repeat soxhlet extraction with C2H5OH
g. Dry and evaporate the extract with Na2SO4
h. Addition of petroleum ether and cooling = Cafestol diacetate
By this process it was possible to extract almost exactly one gram of
chemically pure cafestol diacetate from one liter of beverage coffee.
A comment is in order here: Dr. Green overstated his case by claiming that
Lam, Sparnins and Wattenberg23 “demonstrated that
kahweol and cafestol, the palmitate constituents of green coffee beans, induced
GST activity and that roasting destroyed most of this GST-stimulating activity.”
That is not what they reported, but rather, this: “Roasted coffee and instant
coffee were found to have a weaker inducing activity than did the green coffee
beans studied, i.e., slightly less than 50% as much.”23
These were feeding experiments in which the same amount of each material was
mixed with animal chow. Larger amounts of the less potent inducers can make up
the difference. Dr. Green also questioned the solubility of the esters in water
when he claimed “the roasted, ground coffee used in the Gerson coffee enema
solutions cannot contain kahweol and cafestol.” Our result shows that Dr.
Green does his chemistry at his desk instead of taking it to the laboratory
bench. That Lam did not extract either ester from green coffee beans with water
may be due to the fact that they were green as opposed to roasted, or that he
filtered the boiled coffee solution used in his experiments.26
2. A choledochocutaneous fistula was surgically created in 30 Wistar rats
(avg. body weight 280 grams) so that the end of the common duct was implanted
into the anterior abdominal wall like a sigmoidostomy. Miniature ostomy bags
were created from condoms and adhered to the rats with skin paste supplied by
3. Based on the consideration that the average human (70 kg) is given a
coffee enema containing 1 gr. cafestol, the equivalent dosage for rats was set
at 4 mg. Suppositories were made from white wax. Half were medicated with 4 mg
cafestol extracted from beverage coffee as described above. Half were left
unmedicated and given to the controls as placebos. There were fifteen rats in
4. Bile flow was measured after eight hours. The average output of bile for
the controls was 2.4 ml, whereas the average for the test animals was 3.1 ml.,
an increase of 28%. The difference is statistically significant.
These experiments provide grounds for speculation and further studies. But,
as one of us has already written: “However, the continuation of these
investigations is beyond our scope and should be reserved for the pharmaceutical
industry, together with a possible clinical test. As long as the substances
under discussion, which in our view could make a highly effective drug for
protecting the liver, are not produced industrially and no relevant studies are
planned, we have to continue administering them in the awkward form of enemas.
All the more so because patients cannot be expected to consume the
therapeutically necessary daily amount of at least one litre of coffee by
drinking it, without risking side effects in the upper alimentary tract.”20
In unrelated animal experiments, Miller27 demonstrated
that DMBA-induced buccal pouch tumors in hamsters could be markedly inhibited
(35%) by either cafestol or kahweol administered as a dietary supplement. In
earlier experiments by the same investigator, green coffee added to feed evoked
even greater (90%) protection.28
Treatment of cancer pain by coffee enemas
Because cancer pain remains a problem, even with the development of better
medications, we continue to focus on the benefits of coffee enemas specifically
for cancer pain. Currently, we are conducting a prospective trial in advanced
cancer pain control, comparing the need for pain medication in patients
receiving only standard treatment (Group A) with those receiving standard
treatment and a modified Gerson diet therapy with two coffee enemas per day
(Group B). Patients, almost all with cancers of the breast, bowel, or pancreas,
are matched for gender, age, weight, race and disease, including sites of
primary tumor and metastases. The trial was begun in April of 1991.
Pain is assessed by the patient himself with a visual analog scale published
in the cancer pain treatment guidelines of the World Health Organization.29-31
There are four stages of pain, each with its own set of medications.
Verification of patient self-assessment is made by challenging his pain with the
medications appropriate to his stage.
Stage I pain. To date, 42 test and 49 control patients have been
evaluated. Patients at this level can be kept pain free with three doses per day
of indomethacin 75 mg., diclofenac 100 mg., or paracetamol 500 mg. The test
group has used 71.3% less medication than the control group. The difference is
highly significant (p.<001).
Stage II pain. 27 test and 41 control patients have been recruited to
Stage II. They are pain free with a maximum of three doses per day of codeine 60
mg., or tramadol 50 mg. The test patients used 59% less analgesic than the
Stage III pain. Recruitment has been slow and the sample is still too
small for statistical significance. There have been only 12 test and 7 control
patients. Patients at this level can be free of pain by relying on one
medication from the Stage I group and an additional medication from the Stage II
group. The test group thus far has used 22% less medication than the controls
but the data are not yet significant.
Stage IV pain. These patients require continuous application of
narcotics like morphine and buprenorphine. The combination of two coffee enemas
per day and the modified diet no longer provide additional relief from pain at
this level. There have been 39 test patients and 72 controls. At this level, and
at level III, there is continuous turnover of patients due to a median survival
of only 7.2 months.
Dr. Green believes that we “do not use the diagnostic methods that are
available,” but has offered no evidence and cited no literature to bolster
his opinion. From time to time, we have demonstrated to colleagues and laymen
evidence of remarkable control or regression of disease in exceptional tumor
patients. These cases are not held out by us as evidence that here is a “cure”
for cancer, but rather that some patients can get well. We present such cases
because we believe that Gerson’s integrated set of medical treatments may have
contributed to their unusually positive outcomes. Contrary to Dr. Green’s claim,
in order to convincingly present cases to medical professionals, we are obliged
to rely on the usual types of objective evidence of tumor regression, i.e.:
biopsy, CT, MRI, ultrasound, radionuclide scan, etc.
This response would not be complete if we did not point out that modern science does not support Dr. Green’s speculation that enzymes from vegetable juices, taken as nutrition, entering “the circulation of the patient might evoke a potentially dangerous immune response.”
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