THC in Hemp Foods and
Cosmetics: The Appropriate Risk
Assessment
Dr. Geiwitz was part of the Ad Hoc Committee
on Hemp Risks, an impartial scientific organization commisioned
by Health
Canada to assess the risks of hemp-based food and
cosmetic products. This paper is a cornucopia of knowledge just
waiting to be soaked up by your brains about the effects of THC,
other cannabanoids, and cannabis in general on the physical and
mental health of both humans and animals. Dr. Geiwitz appeared as
an expert witness in Ted's court case. Many thanks to Dr.
Geiwitz for providing Hempology with this incredible literature
and giving us permission to publish it on our website.
by James Geiwitz,
Ph.D., and the Ad Hoc Committee on Hemp Risks
January 15, 2001
EXECUTIVE SUMMARY
In 1998, industrial hemp became a legal crop in
Canada, promising environmentally-sound farming and processing of
fibre for paper, textiles, and building products. In addition,
hemp seed is among the world’s most nutritious foods, and
its oil is an exceptional bodycare emollient.
In 1999, Health Canada issued a draft report
entitled Industrial Hemp Risk Assessment. The report dealt only
with hemp foods and cosmetics (bodycare products) and focused on
tetrahydrocannabinol (THC), the psychoactive ingredien in
cannabis hemp. By law, hemp foods and cosmetics must contain less
than 10 parts per million THC. Health Canada concluded that, even
with THC content limited to 10 ppm, “inadequate margins of
safety exist between potential exposure and adverse effect levels
for cannabinoids in cosmetics, food, and nutraceutical products
made from industrial hemp.” Health Canada, therefore, is
considering a ban on hemp foods and cosmetics.
The purpose of the Ad Hoc Committee on Hemp Risks
is to respond scientifically to the Health Canada risk
assessment. We focused on four allegations by Health Canada:
acute neurological effects and toxic effects on brain
development, reproductive system, and immune system. In contrast
to the Health Canada conclusions, we found absolutely no health
risks from the extremely low doses of THC present in hemp foods
and bodycare products. In fact, the best research indicated some
health benefits of THC, most notably in the strengthening of the
human immune system.
How can it be that scientists at Health Canada
review the research literature on the effects of THC and conclude
that hemp foods and cosmetics are unsafe, while another group,
our Ad Hoc Committee, reviews the same research and concludes the
exact opposite? In our analysis of the science of THC risk
assessment, we identified the major problems with the research
referenced by Health Canada, including extreme dosing,
inappropriate extrapolation to humans from animal studies, and
political pressures on scientific disinterest. Also, contrary to
assumptions made by Health Canada, children are at less risk from
THC than adults; hemp THC must be heated to be biologically
active (which means the THC in cold- pressed hemp oil is
inactive); and only two or three cannabinoids are candidates for
investigation in hemp foods, not 66.
We next calculated, from our data, the
appropriate standards for THC in hemp foods and cosmetics.
Although there are no health risks from THC, we set the standard
at the threshold for psychoactive effects, with a safety factor
of 10. Scientifically determined, the maximum THC in hemp oil
(the most efficient carrier) should be set at 20 parts per
million a conservative estimate, with other studies
recommending limits as high as 50 ppm. Current Canadian
regulations,which set the standard at 10 ppm, represent a
difficult but achievable practical limit for bulk hemp
manufacturers.
Finally, to complete a cost/benefit analysis, the
health benefits of hemp foods and cosmetics were explored. In
foods, the essential fatty acids (EFAs) and the high level of
protein make hemp nuts an exceptionally nutritious food; a
healthy heart is perhaps the most well-documented benefit. The
EFAs and the protein are basic building blocks of the body,
involved in health at the cellular level. The same EFAs are the
primary ingredient in hemp bodycare products, which heal and
nurture the skin and prevent infections.
We conclude that a ban on hemp foods and
cosmetics would be ill-advised policy based on a flawed review of
the research literature. Rather than protecting the health of
Canadians, such a ban would be damaging. We propose instead that
current THC regulations be retained, and the health benefits of
hemp foods and cosmetics be the topic of Health Canada reports on
industrial hemp.
TABLE OF CONTENTS
- 1.0 INTRODUCTION
- 1.1 The Ad Hoc Committee
- 1.2 Outline of the Committee’s Response
- 2.0 THE TOXICOLOGY OF THC
- 2.1 Genetic Effects
- 2.2 Pregnancy and Offspring
- 2.2.1 Pregnancy
- 2.2.2 Birth defects and brain development
- 2.3 Hormonal Systems and Reproductive
Capabilities
- 2.4 Immune System
- 2.4.1 Suppression versus enhancement
- 2.4.2 Humans and disease
- 2.5 THC and Cancer
- 3.0 THE SCIENCE OF THC RISK ASSESSMENT
- 3.1 Extreme Dosing
- 3.2 Cannabinoid Receptors and Tolerance
- 3.3 Cannabinoid Receptors in Children
- 3.4 Effective Forms of THC
- 3.4.1 Cannabinoids other than THC
- <3.5 Extrapolation from Animal Studies
- 3.6 The Fallibility and Abuse of Science
- 4.0 DETERMINATION OF TRUE HEMP RISKS
- 4.1 LOELs and NOELs
- 4.1.1 Appropriate safety margins
- 4.2 Exposure and NOEL
- 4.2.1 Maximum levels of THC, properly
determined
- 4.2.2 Comparisons of THC limits
- 5.0 BENEFITS OF HEMP FOODS AND COSMETICS
- 5.1 Benefits of Hemp Foods
- 5.1.1 Hemp oil
- 5.1.2 Hemp nuts, hemp flour, and hemp protein
- 5.2 Benefits of Hemp Bodycare Products
- 6.0 CONCLUSIONS
- 7.0 REFERENCES
1.0 INTRODUCTION
Industrial hemp (Cannabis sativa L.) became legal in
Canada on March 13, 1998, and
the first crops were planted in the summer of 1998.
On March 3, 1999, Health Canada (HC) issued a draft report
entitled Industrial Hemp
Risk Assessment. The report was prepared by Joan Orr, M.Sc., and
Mary Starodub,
M.Sc., for Hugh Davis, Head of the Microbiology and Cosmetics
Division of the
Product Safety Bureau of Health Canada. On July 27, 1999, the
Toronto Globe & Mail
published a story on the draft risk assessment. The report was
revised several times,
the latest dated September 9, 1999.
The HC report dealt only with hemp foods and cosmetics, not
the fibre products
such as paper and textiles. The focus of the report was
tetrahydrocannabinol (THC),
the psychoactive ingredient in cannabis, responsible for the
“high” in marijuana,
the high-THC cousin of industrial hemp. Other cannabinoid
ingredients were
occasionally considered, although research on the other
cannabinoids is sparse.
By law, industrial hemp must contain less than 0.3% THC,
10-100 times less than the
amount of THC in marijuana. The industrial hemp seed
(botanically, a nut), from
which hemp foods and cosmetics are made, contains only trace
amounts of THC, but
it cannot be cleaned and processed without some microscopic
contamination from
the bracts and leaves of the hemp plant, the primary sites of THC
production by the
plant. By law, industrial hemp foods and cosmetics must contain
less than 10 parts
per million (ppm) THC.
The question posed by the HC report was this: Do hemp foods
and cosmetics
containing 10 ppm THC or less present health risks for Canadian
consumers?
Here is their answer: “Overall, the data considered for
this assessment support the
conclusion that inadequate margins of safety exist between
potential exposure and
adverse effect levels for cannabinoids in cosmetics, food, and
nutraceutical products
made from industrial hemp.”
Dr. Hugh Davis, for whom the risk assessment was performed,
believes that hemp
foods and cosmetics should be prohibited unless the industry can
develop
techniques for the total elimination of THC (and 65 other
cannabinoids) from the
hemp seeds. As the hemp nutmeat itself may contain faint traces
of THC (Ross et
al., 2000), such absolute elimination may not be practical.
A further problem is that methods for detecting THC levels in
hemp products are
constantly evolving, allowing for the detection of more and more
minute
quantities. Thus, the definition of “zero tolerance”
is constantly shifting, and an
industry “in compliance” today might be violating the
standards tomorrow. The
concept of “zero tolerance” developed from the U.S.
War on Drugs, not from health
research practices. Not even deadly food contaminants (e.g.,
pesticides) are held to
such impossible restrictions, and popular foods containing trace
amounts of other
natural drugs (e.g., morphine, cocaine) are not a matter of
official concern.
Dr. Davis suggested that the industry explore genetic
engineering of the hemp plant
to eliminate the THC. We believe that genetic engineering might
pose significantly
more and greater risks than THC, both to the environment and to
the health of
Canadians, although longterm studies have yet to be done.
Elimination of
cannabinoids may also affect crop susceptibility to pests (Pate,
1999b). In any case,
genetic engineering would violate official definitions of
“organic” food and thus
significantly damage the marketability of hemp products.
1.1 The Ad Hoc
Committee
To evaluate the claims in the risk assessment and to provide
an industry response
to the report, Dr. James Geiwitz and Dr. Chuck Schom formed the
Ad Hoc
Committee on Hemp Risks and invited hemp scientists from around
the world to
join. Here is a list of current members, briefly identified:
- B. Marc Alfred, Ph.D., Professor of Biological Anthropology
(emeritus),
University of British
Columbia, Vancouver, BC
- Jace Callaway, Ph.D., Department of Pharmaceutical Chemistry,
University of
Kuopio
(chemistry of hemp foods), Kuopio, Finland
- Paul Consroe, Ph.D., Professor of Pharmacology and
Toxicology, University of
Arizona (research on cannabis and cannabinoids; founding member
of the
International Cannabinoid Research Society),
Tucson, Arizona, USA
- Jozsef A. Durgo, Ph.D., D.Sc., Hemp Scientific
International, Richmond, BC
- Jason Freeman, President of Biohemp Foods (hemp food
research), Regina,
Saskatchewan
- James Geiwitz, Ph.D., Director of Research, Transglobal Hemp
Products
(experimental design
and analysis), Victoria, BC
- Franjo Grotenhermen, M.D., nova Institute; chair,
International Association for
Cannabis as
Medicine (toxicology of THC in hemp foods), Hurth, Germany
- David Hadorn, M.D., health research (pharmacology and
toxicology of hemp),
Victoria,
BC
- Arthur Hanks, Editor, The Hemp Report (formerly the
Commercial Hemp Farm
Report), Regina,
Saskatchewan
- Eric Hughes, President of Zima Foods (hemp food
research), Victoria, BC
- Peter Kendal, C.Eng., M.I.Mech.E., formerly Engineering and
Administration
Manager, Omega Biotech Corporation (a nutraceutical company),
Vernon, BC
- John P. Morgan, M.D., Professor of Pharmacology, CUNY Medical
School, New
York, NY,
USA
- David W. Pate, Ph.D., M.Sc., Senior Technical Officer,
HortaPharm BV (botany and
chemistry of
cannabis), Amsterdam, The Netherlands
- Chuck Schom, Ph.D., New Brunswick integrated hemp industry
(hemp genetics and
agriculture),
St. Andrews, NB
- Phil Warner, Managing Director and Chairman of the Board of
Australian Hemp
Resource and Manufacture (AHRM), Brisbane, Australia
In addition to the members of the committee, we have 14
associates who follow our
research and exchange information. These include scientists from
The Body Shop
(England), which markets hemp cosmetics. The Body Shop has
produced its own
response to the HC risk assessment; we incorporate their findings
into our response.
The Committee’s work was accomplished entirely by
e-mail, from July 27, 1999, to
the present. The Committee relied entirely on volunteer labour,
which accounts for
the brevity of this response. A rebuttal of Health Canada’s
risk assessment, over 400
pages long, deserves a point-by-point, fully referenced response
of comparable
length, which, unfunded, we were unable to provide. For instance,
we were unable
to reference the original data sources for many of the statements
in this document,
although, for critical issues, the primary research is cited. In
other cases and
especially for research summaries, our secondary sources were
book-length reviews
of THC research by two committee members, Dr. Franjo
Grotenhermen
(Grotenhermen et al., 1998) and Dr. John P. Morgan (Zimmer &
Morgan, 1997). In
these documents, the reader will also find references to primary
sources. (It is
worthy of note that the Grotenhermen and the Zimmer/Morgan
reviews agree in
every significant conclusion.)
1.2 Outline of the Committee’s
Response
An outline of Health Canada’s Risk Assessment report is
provided in the Appendix.
Our response comprises three major sections. The first (Section
2) focuses on
research on the toxicology of THC, specifically four toxic
effects alleged by HC:
- acute neurological effects
- brain development
- reproductive system
- immune system
Section 3 will examine some of the inappropriate methods and
conclusions of the
Health Canada risk assessment: what went wrong with this badly
flawed report, and
why.
Section 4 of this response will focus on the determination of
safe exposure levels for
THC in hemp foods and cosmetics, that is, the appropriate risk
assessment. Topics
covered include:
- determination of No Observed Effect Levels
(NOELs)
- exposure versus NOELs in hemp foods and
cosmetics
- acceptable margins of safety
- determination of appropriate limits to THC in
hemp products
- comparison of Canadian, Swiss, and German exposure
standards
Section 5 provides a brief description of the health benefits
of hemp foods and
cosmetics, benefits that would be lost to Canadians if hemp foods
and bodycare
products were banned.
2.0 THE TOXICOLOGY OF THC
It is our position that THC is one of the least toxic
chemicals that humans ingest. At
normal doses, there is no evidence of genetic damage due to THC
exposure or effects
on fertility, pregnancy, or offspring. Similarly, there is no
evidence of damage to the
hormonal or immune systems. These statements apply to humans who
ingest large
quantities of marijuana daily, and much more so to humans who
ingest trace
amounts of THC through hemp foods. Ingestion through hemp
bodycare products
is completely undocumented and highly unlikely.
Research that finds damaging effects of THC generally falls
into one of two
categories:
- studies that are not replicated by later research using more
appropriate
experimental
designs; and
- studies that use massive quantities of THC, far beyond
the doses employed by heavy marijuana users.
2.1 Genetic Effects
In doses typical for consumers of marijuana, THC is not
genotoxic, mutagenic, or
carcinogenic, and it has no effect on cell metabolism. THC does
not result in
chromosomal breaks.
At extremely high doses applied directly to cells, THC reduces
the synthesis of DNA,
RNA, and proteins. These effects are nonspecific, that is,
unrelated to the typical
receptor activation in the human body.
In regard to genotoxic effects, the trace amounts of THC in
hemp foods and
cosmetics are obviously safe for consumers.
2.2 Pregnancy and
Offspring
Animal studies of the effects of THC on pregnancy are
inconsistent, even with doses
of 10-20 mg/kg, a hundred times higher than the LOEL for
psychotropic effects. A
few studies purported to show impairment of cerebral development
in children of
chronic cannabis consumers, but these studies were never
replicated and are now
discredited. The NOEL for pregnancy variables (parturition,
duration of pregnancy,
infantile abnormalities, birth weight) is above the range of
human consumption by
chronic marijuana consumers, which is much higher than THC levels
from hemp
foods and cosmetics.
There is no realistically demonstrated danger to pregnant
women or their offspring
from consumption of hemp foods, and clearly none at all from use
of hemp
bodycare products.
2.2.1 Pregnancy
Greenland et al., 1982, found more meconium staining and
longer duration of
labour in marijuana users, but this study has never been
replicated, even by
Greenland’s lab. For centuries, cannabis has been used for
pain relief during birth.
The general conclusions permitted by the research are that no
birth complications
can be observed in mothers who ingest marijuana levels of THC
over a long period
of time and that the trace levels of THC in hemp foods and
cosmetics are obviously
safe.
Gibson et al., 1983, found more premature births in marijuana
users, but this study
has never been replicated. Most studies find no marijuana-induced
change in the
duration of gestation.
2.2.2 Birth defects and brain development
Birth defects associated with THC have been found only in
animal studies in which
the THC was injected, in very high doses, directly into the
abdomen. In humans,
there is no evidence whatsoever for a link between marijuana use
and fetal
malformations or Minor Physical Anomalies (MPAs).
Studies that show a decreased birth weight in rat pups after
THC ingestion have
been clearly discredited. The decrease, when it occurs (at high
doses), is due to
reduced food and water intake of exposed dams; there is no
difference between these
animals and pair-fed controls.
Evidence is accumulating that the cannabinoid-anandamide
receptor system might
play a role in cerebral development in fetuses and neonates.
Daily administration of
5 mg/kg THC to pregnant rats doubles the activity of the enzyme
tyrosine
hydroxilase (TH) in specific brain cells of their fetuses
(Hernandez et al., 1997). TH is
believed to be a key factor in the development of neurons. In
contrast, one animal
study has established a disturbance of mesolimbic dopaminergic
neurons among
perinatally THC-exposed males which persists in adult animals
(Garcia-Gil et al.,
1997). However, the significance of these data for humans using
hemp foods and
cosmetics is very probably nil.
Animal studies have generally found behavioural problems only
at high doses. For
example, no behavioural effects in offspring were observed after
dosing the
pregnant rats with 50 mg/kg/day. Hutchings et al., 1987, found
nipple attachment
problems in rat offspring exposed to 50 mg/kg/day, but the
problems were clearly
related to decreased food and water intake in the dams; the
offspring of pair-fed
controls were indistinguishable from the offspring of
experimental animals.
In humans, the offspring of chronic users show no differences
from normal in
sleeping, eating, mental tests, and psychomotor tests. One
researcher (Dreher, 1994,
1997) found the offspring of chronic users to be more lively and
less irritable, with
fewer tremors; these babies were more easily quieted, yet more
responsive to novel
stimuli. These results have not been replicated, but they show
the extreme
inconsistency of marijuana studies. The more common finding is,
simply, no
difference.
Studies that have attempted to find brain damage from THC have
been
unsuccessful. Marijuana levels of THC do not kill brain cells. In
one study,
monkeys were forced to inhale five marijuana cigarettes a day for
a year; there was
no evidence of brain damage (Zimmer & Morgan, 1997). In
humans, with brain
damage assessed by CAT scans, no damage was observed in spite of
the high dose:
nine marijuana cigarettes a day.
2.3 Hormonal
Systems and Reproductive Capabilities
Some high-dosage animal studies suggest that THC may act on
the hypothalamus-
pituitary-adrenal axis and adversely affect the sex steroid
hormones. However,
there is no reliable finding of adverse effects in animals (male
or female) within the
range of human consumption of marijuana. The slight effects that
sometimes
appear, disappear with repeated doses (tolerance). In humans, no
effects were
discovered regarding the function or concentration of sexual
hormones or other
parameters relevant for reproduction such as sperm quantity and
quality.
In one representative study, men were dosed with up to 20
marijuana cigarettes a
day for a month (Hembree et al., 1979). The researchers found
some decrease in
sperm concentrations and motility. The decreased factors were not
outside of
“normal” range, and by the end of the month, the
sperm factors had returned to
normal, despite continued dosing.
In men, a few studies found effects of chronic marijuana use
on luteinizing
hormone (LH), which is related to testosterone production,
although the effect
disappears with time, even if THC doses remain constant. Other
studies found no
such LH effect. There is no effect of THC on testosterone,
follicle stimulating
hormone (FSH), or prolactin. There are no effects on puberty. A
representative
study (Mendelson et al., 1978) found no effect of marijuana
smoking on testosterone
level, in spite of the high doses: 120 marijuana cigarettes in 21
days.
In women, the conclusions are the same: There are no reliable
effects of THC on the
menstrual cycle, estrogen levels, progesterone, prolactin, LH, or
FSH. The few
studies of positive effects involved high-dosage inhalation,
effects that quickly
disappeared as tolerance developed.
In some animal studies, THC reduced the level of
adrenocorticotropin (ACTH),
which is secreted by the adenohypophysis and stimulates the
production of
glucocorticoids (cortisol) in the suprarenal cortex. This result
could not be replicated
in human chronic consumers of marijuana. THC has no effect in
humans on the
thyroid hormones or on glucose metabolism.
2.4 Immune
System
“Cell experiments and animal studies demonstrate that
THC has
suppressive effects on the humoral and cell-mediated
immunity.
However, the majority of those can be attributed to toxic
unspecific
effects. Many analysed parameters required extremely high doses
to
exhibit any significant effect and the effects were
dose-dependent with
the threshold concentration being precisely determinable.
When
applying lower doses, one often observed differentially
immunostimulating effects or no effects at all. For many
immune
parameters the NOEL is … irrelevant to the human
consumption
situation. In studies of man or of cells of marijuana users the
effects
observed were often contradictory. If such effects were found at
all,
they were weak even in case of heavy cannabis use and of
questionable
relevance to health. The World Health Organisation summarised
in
its most recent cannabis report: ‘Many of their effects
appear to be
relatively small, totally reversible after removal of the
cannabinoids,
and produced only at concentrations or doses higher than
those
required for psychoactivity (WHO, 1997, p. 27)’”
(Grotenhermen et al,
1998, p. 53).
2.4.1 Suppression versus
enhancement
THC and the immune system is the most thoroughly researched
topic in the area of
subliminal biological effects. Much of the early research, which
demonstrated
immune-system suppression, has been discredited. For example,
Nahas et al. (1974)
found that THC decreases the number of T-lymphocytes ? which
control cell-
mediated, acquired immunity. Later studies found no such
decrease. Dax et al.
(1989), for example, found no change in T- or B-lymphocytes
(humoural immunity)
or in T-cell subtypes before, during, or subsequent to
administration of THC to
chronic users. Wallace et al. (1988) reported similar findings,
with a twist: an
increase in helper T-cells (CD4). These findings should be
interpreted as
immunoenhancement, because helper T-cells stimulate the
proliferation and
activation of other immune cells.
In a study cited in the Health Canada risk assessment, Nahas
et al. (1977) found in
vitro suppression of T-cell proliferation in response to
mitogens, which stimulate
cell division. Other researchers criticized Nahas’s method
? applying THC in
massive doses to human cells in a petri dish ? and called the
results “meaningless.”
Better studies failed to replicate Nahas’s work and,
instead, found immune system
stimulation at lower doses (Pross et al., 1993; Luo et al.,
1992).
Let us be clear about these findings: What the research shows
is immune system
suppression at very high doses, but immune system stimulation
(enhancement) at
low doses. These effects have been demonstrated for both the T-
and B-lymphocytes.
This means that the trace amounts of THC in hemp foods probably
strengthen the
immune system of humans. High doses have nonspecific toxic
effects, likely the
cause of any damage, whereas low doses act through specific
receptor-based effects.
It’s a basic principle of pharmacology: low doses may be
curative whereas high doses
are poisonous.
One last point: With an oral dose of THC of 0.1-0.2 mg/kg (the
psychotropic
threshold), the blood plasma reaches a maximum concentration of
3-5 ng/ml. In
the cell studies, the concentration is 10 ug/ml, or 10,000 ng/ml
? 2000 to 3000 times
the dose that produces the marijuana “high.”
2.4.2 Humans and
disease
Marijuana smokers show an enhanced response to antigens (which
trigger
antibodies) compared to cigarette smokers and cancer patients
(Hollister, 1992),
which supports the conclusion of THC strengthening the immune
system and casts
additional doubt on the high dosage cell studies. On a more
general level.
absolutely no epidemiological evidence exists relating marijuana
use and infectious
diseases (Hall et al., 1994). In cancer and AIDS patients, THC is
used to reduce pain
and depression, stimulate appetite, and prevent nausea and
vomiting. AIDS
patients, who suffer from a damaged immune system, are not harmed
by THC (Di
Franco et al., 1996).
2.5 THC and
Cancer
Immune-system stimulation by THC at low doses should be
apparent in macro-
level health benefits. The stunning (but rarely reported) success
of THC treatments
of cancer may be representative. One of the first studies had
rats ingest a large dose
(50 mg/kg) of THC daily for two years. At the completion of the
experiment, 70
percent of the dosed animals were still alive, but only 45
percent of the control
(undosed) animals survived. This sizeable difference was due
almost entirely to a
reduced incidence of cancer in the animals given THC (Chan et
al., 1996).
A more direct test of THC’s cancer-fighting properties
was performed on rats with
brain tumours (Galve-Roperh et al., 2000). The tumours, called
gliomas, are fatal in
humans. The researchers infused THC directly into the rats’
brains. The control
rats (no THC) died in two to three weeks. In a third of the
THC-dosed rats, the
tumour was eliminated. Another third lived eight to nine weeks,
instead of the two
to three weeks of the control (no THC) rats. A third of the
THC-dosed rats gained no
benefit. The researchers claim that the THC works by stimulating
the cancer cells to
“commit suicide” in a natural process called
“apoptosis.” Normal cells were
unharmed. The THC in this experiment was very low dosage, and the
cancers were
at a late stage, when untreated rats were already starting to
die. The researchers
suggest that THC would work even better if given earlier.
3.0 THE SCIENCE OF THC RISK ASSESSMENT
Section 4 will focus on the determination of safe
exposure levels for THC. Before
we turn to the appropriate risk assessment for THC in hemp foods
and cosmetics,
we will examine some of the inappropriate methods and conclusions
of the Health
Canada risk assessment. We have come to precisely the opposite
conclusions to
those of Health Canada regarding the risks of hemp products. Both
of us claim
scientific data in support of our position. In this section, we
will list some of the
ways in which Health Canada was mistaken, by inadvertently citing
inadequate
science.
The science of THC is not unlike other areas of science:
Science does not prove
anything. It deals in probabilities, and its methods are designed
to estimate the
degree of error in an estimate or in a probabilistic
relationship. Most scientists view
their procedures as a search for error, whereas the general
public perceives it as a
search for truth. In reality, it is a search for truth by way of
estimating error.
The nature of science is such that one can always argue the
opposite to a suggested
proposition, with some evidence in support. Global warming, for
example, is
supported by the bulk of the evidence, but there are enough data
leaning toward the
opposite conclusion that the National Post can claim that global
warming is a hoax.
Similarly, scientists paid by the tobacco industry can mount a
claim, with data
support, that smoking does not cause lung cancer.
When a scientific question has political ramifications (such
as global warming or
smoking), the goals of science are often perverted, as different
camps seek to
generate evidence for their position. The US War on Drugs is such
a camp.
Beginning in the 1960s, the US government offered scientists
millions of dollars to
“prove that marijuana is harmful.” The research cited
by Health Canada includes
much of this “advocacy science,” which produced
misleading conclusions about the
effects of THC.
The following section is, in effect, a manual on how to do
advocacy science.
3.1 Extreme
Dosing
The major deficiency with most reports of harm from THC is the
massive doses
required to demonstrate such effects. In one study, monkeys were
given the human
equivalent of 15 kg of marijuana in a single dose. Similarly, the
petri-dish studies of
the effects of THC on body cells used concentrations 2000 to 3000
times the threshold
level for psychotropic effects.
The Body Shop, which markets hemp cosmetics, noted that the
Health Canada
estimate of skin penetration of THC (33%) is wildly inaccurate
because the oil used
to calculate the estimate had extremely high levels of THC
(26mg/g). The high
concentration of THC outside the skin encourages penetration,
which is a function
of the difference between outside and inside (where the
concentration is essentially
zero). If hemp oil with 4 ug/g THC constituted 10 percent of a
cosmetic, as is the case
with Body Shop lotions, then about 0.4 ug/g THC would be
available for skin
absorption, that is, about 65,000 times less than the dose used
by Health Canada
(Adams, 1999). In addition, attempts to deliver therapeutic THC
via skin patch have
been unsuccessful (ElSohly, 1998), a further indication of the
safety of hemp
bodycare products.
In a review of the effects of THC on the human immune system
(which found
none), the reviewers note that some animals given large doses do
show effects;
doses are forty to one thousand times the psychoactive doses for
humans (Zimmer
& Morgan, 1997). Similarly, an attempt to find brain damage
in monkeys failed to
do so, in spite of the dose: five marijuana cigarettes a day for
a year.
These are extreme examples, but far from rare. Almost all of
the studies that show
damage from THC use high to very high doses, even compared to
marijuana levels.
When compared to the low doses from hemp foods and cosmetics, the
high-dose
studies are irrelevant.
THC at reasonable levels such as those in marijuana and hemp
foods acts on
compound-specific binding sites (cannabinoid receptors). Only at
high
concentrations (which are not encountered in hemp foods and
cosmetics) do
nonspecific, toxic effects occur. Most if not all chemicals will
damage body cells and
systems at high concentrations for example, numerous deaths
have been recorded
in people who for psychiatric reasons drink excessive amounts of
water. And
pharmaceuticals that are toxic at high concentrations are
beneficial at low doses, as
seems to be the case with THC and the immune system.
3.2 Cannabinoid
Receptors and Tolerance
The fact that THC at reasonable doses acts not nonspecifically
but, rather, specifically
at receptor sites on neurons provides a further margin of safety
for hemp foods and
cosmetics. For one reason, neurochemical receptors generally show
tolerance that
is, decreasing effect with repeated or sustained exposure. For
most harmful
chemicals, the toxicity increases (and the NOEL decreases) with
duration of
exposure. But, with THC, the opposite occurs, because of
tolerance. For example,
high doses of THC in female monkeys resulted in hormonal changes
and a
disruption of their menstrual cycle. After six months of high
doses, the hormone
levels and the menstrual cycles returned to normal (Smith et al.,
1983). Tolerance
can be observed in the cases of most THC effects.
Chronic exposure to THC does not irreversibly alter the
cannabinoid receptors
(Westlake et al, 1991).
At the low doses of hemp foods and cosmetics, THC’s
effects are almost entirely
receptor based, with little or no nonspecific toxicity. This
means that even if a
troubling effect of low-dose THC were to be established, the risk
would be
shortlived.
3.3 Cannabinoid
Receptors in Children
According to the Health Canada risk assessment, infants
experience greater exposure
to THC from hemp foods and cosmetics for four reasons:
- they have less fat to sequester the lipophilic
THC
- they have less lipoprotein for binding THC
- they have an immature hepatic microsomal enzyme system,
therefore less capacity for metabolism
and excretion
- the infant brain has a greater density of cannabinoid
receptors than
the adult brain
We have some concern with the first three points. First,
compared to adults, infants
have a higher percentage of body fat relative to lean mass,
although the absolute
volume of fat is of course less. Second, although infants do have
less lipoprotein,
the level reaches adult proportions by two to three years. And
third, hepatic
metabolism may not be a desirable function, if THC metabolites
are more
psychoactive than THC itself. In any case, we consider these
facts irrelevant, since
low levels of THC present no risk.
Our research indicates that the fourth point is mistaken.
Children have a
significantly lower density of cannabinoid receptor sites. They
are therefore less, not
more, susceptible to the effects of THC (Grotenhermen et al.,
1998). We recognize
that this issue is a controversial one, with research supporting
both positions.
Because this is such an important point, we examine the research
in some detail.
The preponderance of research data supports our position. One
of the studies that
does not, one that is the basis for Health Canada’s claim,
attempted to determine the
density of cannabinoid receptors in the fetus and neonate (Glass
et al., 1997). These
researchers concluded that concentrations of receptors in these
subjects were
“extremely high.” One fetal brain (33 weeks
gestation) and two neonatal brains (3
and 6 months of age) were examined, a sample too small for valid
conclusions. The
fetus died in utero of bowel obstruction, one neonate died of
congenital heart
disease and the other of asphyxia; the first two subjects must be
considered
“abnormal.” What this means we do not know.
It’s possible that the fetus was
reacting to its bowel obstruction by producing high levels of
endocannabinoids,
which could stimulate the production of cannabinoid receptors
(Callaway, 2000).
There was a post mortem delay of up to 21 hours, a delay that
may affect receptor
profiles. The autoradiograms of fetal and neonatal tissue were of
poor to fair
quality, in contrast to those of adult tissue, which were
extremely high quality. The
fetal and neonatal tissue was processed separately from that from
adults, which
even the authors agree, requires considerable care in comparing
results from
children and adults. And their conclusion of more receptors in
young brains is
qualified: “Due to the small number of cases available for
the study, it is not possible
to draw any definitive conclusions of the precise levels of
cannabinoid receptors …
within the developing brain” (Glass et al., 1997).
This is hardly a “definitive study,” certainly not
one on which to base public policy.
Research that supports our position includes a study of rats
that discovered an
increase of cannabinoid binding from birth to day 30, which
corresponds roughly to
human adolescence (Rodriquez de Fonseca et al., 1993). These data
indicate a lower
density of receptors in younger subjects. Another rat study found
a 470% increase
from birth to day 60, in all brain areas investigated (Belue et
al., 1995). A third found
receptor binding increasing almost 50 percent with increasing age
(McLaughlin et al.,
1994).
It is true that children generally respond more severely to
chemical toxins and
require a greater margin of safety than adults. But in the case
of THC, which
operates on specific receptors, children require a smaller margin
of safety because
they have many fewer receptors. Children with cancer, for
example, tolerate
considerably higher doses of THC than adults, with no symptoms of
psychoactivity
(Abrahamov et al., 1995). This research group later studied, in
mice, the response to
anandamide and THC; there was no response to anandamide for the
first 23 days,
whereas a small response to THC began between days 15 and 20. The
researchers felt
that their results were compatible with their human data showing
that children
respond to the antiemetic effects of THC without psychotropic
side effects (Fride &
Mechoulam, 1996). A similar study of children with cancer taking
nabilone, a THC
analog, found that high doses were well tolerated:
“Particularly for some adolescent
patients, it can turn a five day course of chemotherapy from a
dreaded ordeal into
something accepted with a shrug of the shoulders” (Dalzell
et al., 1986).
To summarize, most researchers find cannabinoid receptors in
newborns, but
receptor populations in children are significantly smaller than
in adults; also,
receptor binding in children is significantly less. Clinical
studies of children with
cancer find that children tolerate much higher doses of THC than
adults. While
more research needs to be done, the pattern of data is quite
clear: Children can
tolerate much higher levels of THC in hemp foods and bodycare
products than
adults.
3.4 Effective
Forms of THC
In unprocessed hemp, THC occurs in the form of a monocarbon
acid (THCA) that is
not absorbed well by the intestines. One cannot, for example, eat
uncooked
marijuana and expect much of an effect. THC must be converted
(decarboxylated) to
its phenolic form to be bio-effective, which is accomplished by
the application of
heat. Smoking and baking are typical conversion methods. This
means unheated
hemp foods, such as cold-pressed oils, contain mostly inactive
forms of THC.
Absorption of THC by human intestines depends on properties of
the carrier.
Lipophilic carriers, such as hemp oil, promote absorption of
decarbosylated THC. If
the carrier is less fatty, as in hemp breads or beverages, the
bioavailability of THC is
reduced by 50 percent or more. Even Health Canada accepts that
hemp beer and
wine presents no risks.
3.4.1 Cannabinoids other
than THC
The Health Canada risk assessment repeatedly makes the point
that there are 66
cannabinoids in industrial hemp, that THC is only the best known
and most
frequently studied. This number is misleading. It represents the
sum total of
cannabinoids found in detectable quantity in at least one
cannabis variety in at least
one study in the history of cannabis research. Health Canada
contends that, even if
the risks of hemp foods and cosmetics from ingestion of THC are
shown to be
minimal, the hemp industry must also show that the risks from the
other 65
cannabinoids are also so. Such research would require years, if
not decades. This
open-ended contention is unprecedented for a natural food product
or drug source
(e.g., coffee, alcohol, tobacco), which may contain scores of
untested chemical
components.
The only cannabinoids proven to be manufactured by the hemp
plant are THC,
CBD, CBC, and (presumably) their common biogenetic precursor, CBG
(Pate, 2000).
CBD predominates, with an accompanying fraction of THC. CBC is
found in
significant quantities only in tropical marijuana. CBG is found
only in very small
amounts. To this short list can be added minor quantities of the
THC degradation
products, CBN and delta-8 THC. The remaining 60 cannabinoids
exist in almost
undetectable amounts in fact, usually none at all in
any given hemp sample.
Health Canada admits that CBD poses few risks. CBN, according to
Health Canada,
is as dangerous as THC, but the research that
“proves” this is the same research that
“proves” that THC is risky. We believe this research
to be problematic, if not
invalid.
Since we have been unable to discover any significant health
risks from the far
more potent marijuana, it is unlikely that any ingredient of hemp
foods and
bodycare products pose health risks to human consumers.
3.5
Extrapolation from Animal Studies
A major disagreement exists between the Health Canada report
and our research
group regarding the value of animal studies for the determination
of risks to
human consumers of hemp foods and cosmetics. Many of the risks
reported by
Health Canada come from studies in which high doses were given to
rats or mice.
That’s OK, says Health Canada, because of
“similarities” between humans and
rodents in the pharmacokinetics and metabolism of THC and in the
brain
distribution of cannabinoid receptors.
However, the application of rat data to human risk assessments
is an uncertain and
often misleading extrapolation, with numerous pitfalls. For
example, the
extrapolation of doses is problematic. Typically, a dose given to
rats is reported in
milligrams of THC per kilogram of body weight. The dose for
humans to produce
the same effects is then calculated using the body weight of
humans. The average
human weighs about 70 kg. So an effect caused by a 2 mg dose to a
rat weighing 0.2
kg translates to a 700 mg dose to humans (about 50 times the dose
for a human
“high”).
This kind of extrapolation may be meaningless, because many
biological processes
(e.g., metabolic rate) are unrelated to body weight. For this
reason, some researchers
use comparisons of body surface (mg/m2) instead of body weight.
It has been found
that body-surface comparisons predict more accurately human
tolerance for anti-
cancer drugs from animal data than do body-weight comparisons.
But body surface
is also a poor basis for extrapolation for many drugs. Other
bases include
pharmacokinetics (absorption, metabolism, excretion, etc.) and
toxicological
estimates such as the “lethal dose” studies.
The lethal-dose studies are a lesson: In rats, the lethal dose
is around 1300 mg/kg.
Extrapolated on the basis of body surface, the lethal dose in
dogs should be about
350 mg/kg and in monkeys, about 650 mg/kg. But dogs lived after a
dose of 3000
mg/kg, and monkeys survived 9000 mg/kg. The lethal dose in these
animals could
not be established. The primates should have been 50 percent more
sensitive to
THC than rats, but were at least five to ten times less
sensitive. The extrapolation
from rats to higher mammals was wildly inaccurate.
There are significant differences between the reproductive and
hormonal systems of
rats and mice and those of humans (Mendelson and Mello, 1984).
Mice, for
example, are especially disposed to fetal malformations. In
general, data on smaller
animals leads to highly inaccurate estimates of THC toxicity in
larger animals.
Reliable data on the toxicity of THC in humans must be based
on studies with
human subjects.
3.6 The
Fallibility and Abuse of Science
Studies of the effects of THC on humans are inconsistent, for
a number of reasons:
Many studies use small samples (that is, few subjects), and
small-sample studies are
notoriously unreliable (that is, inconsistent). For scientific
purposes, small-sample
studies are practically worthless. A young man who smokes pot
fails to go through
puberty; the child of a pot smoker develops cancer: These are
meaningless
anecdotes, although such studies are widely touted as proof of
THC’s dangers.
Most of the marijuana studies on humans compare chronic users
with “matched”
control subjects. This experimental design produces data that are
often misleading,
because the researchers are comparing two groups that differ in
many ways. True
matching is impossible, since one can never know all the factors
that influence the
life of a test subject. For example, many chronic marijuana
smokers use other drugs
as well, including cigarettes and alcohol. In addition, human
subjects often lie about
their drug use, making assignment to groups difficult. Results
from such studies are
often unreliable or difficult to interpret.
As we’ve mentioned, the US War on Drugs has distorted
the scientific
infrastructure and produced a plethora of biased findings. A
study that purports to
have found deleterious THC effects is quickly published, whereas
a study that finds
THC safe is not. In the latter case, researchers may suppress the
data or peer review
might disparage the experiments (Levy and Koren, 1990). Finally,
if well-designed
experiments demonstrating the safety of THC are published,
government
publications often ignore them, focusing instead on the studies
that support the
official view. This pseudo-science we have termed “advocacy
science.”
True science consists of a search for conclusions to explain
previously established
facts, theories to explain observed data. Advocacy science
consists of a search for
facts to support a previously established opinion.
4.0 DETERMINATION OF TRUE HEMP RISKS
In this section, we present our determination of a THC
level in hemp foods and
cosmetics that is clearly safe for human consumption. This
determination was
conducted for the German hemp industry by Dr. Franjo
Grotenhermen, a member
of our committee (Grotenhermen et al., 1998).
4.1 LOELs and
NOELs
Our first step is to determine the No Observed Effect Levels
(NOELs) and Lowest
Observed Effect Levels (LOELs) for the psychoactive effects of
THC. Our review of
the research clearly shows that if THC levels are below the NOEL
for psychoactive
effects, there will be no other risks to health.
The LOEL for THC’s psychoactive effects is 0.2 to 0.3
mg/kg, about 10 - 20 mg THC in
a single dose to an average adult. The NOEL, the level of THC
that cannot be
distinguished from placebo (no THC) effects, is .07 mg/kg, about
5 mg for an average
adult. At the effect duration of four hours, the NOEL is 5 mg
twice a day, or 10
mg/day.
The application of a safety factor of 10 results in a
tolerable daily dose of 14 ug/kg,
about 1 mg THC for a 70 kg adult. This dose will have no
psychoactive effects and
no adverse health effects.
4.1.1 Appropriate safety
margins
Health Canada applied a safety margin of 1000 to its flawed
determination of THC
LOELs. We believe that this safety margin is ridiculously large,
a hundred times the
industry standard of 10 (Kendal, 2000). Health Canada justified
its safety margin as
follows: 10-fold for interspecies differences, 10-fold for
intraspecies differences, and
10-fold for lack of data from chronic studies. As we have seen in
the review of
research, the interspecies differences (especially comparing
human risks to toxic
effects from high-dose rodent studies) are in the opposite
direction from that
proposed by Health Canada, that is, humans are less at risk than
would be assumed
from the rodent findings (even if extrapolation calculations were
accurate, which
they are not). Similarly, the intraspecies differences are such
that estimation of
NOELs with adults will protect children, with fewer receptors,
even more.
Chronic consumption of THC will not increase risk, it will
decrease it. THC
receptors typically develop tolerance, so that a continuous
supply of THC does not
lead to an increase in possible health impairments (and a
decrease in NOEL), as is
common with most toxic chemicals. And, although we can always use
more
chronic studies of humans, there is no evidence that we will be
misled by using the
many chronic studies we now have.
We believe that a safety factor of 10 is conservative.
4.2 Exposure and
NOEL
The research on absorption of THC clearly shows that the
greatest risk is with adults
ingesting hemp oil that contains THC in its active phenolic form.
(We disregard the
fact that cold-pressed hemp oil is likely to contain more
inactive THC acids than
active THC forms.) Lipophilic carriers such as oils promote
absorption; THC
absorption in hemp breads, in contrast, is reduced by 50 percent;
in hemp beverages
and cosmetics, absorption levels are even less, or nil.
The average daily consumption of hemp oil for Germans who
consume this
product is 33g/day. The German figure is probably high for the
Canadian situation,
since Germany has had a vital hemp industry for many years. But
we will use it
anyway, and add a further safety factor, 1.5, to account for
increased consumption as
the world recognizes the health benefits of hemp foods. So our
exposure figure is
50g/day/consumer.
4.2.1 Maximum levels of
THC, properly determined
The NOEL for THC, as determined in Section 4.1, is 1 mg for an
average adult. With
consumption of hemp oil (in which absorption is greatest) of 50
g/day/capita, the
maximum THC content of the oil, if we don’t want to exceed
the NOEL, should be
.020 mg per g of oil, or 20 mg/kg. Scientifically determined, the
maximum THC in
hemp oil should be set at 20 parts per million (20 ppm).
4.2.2 Comparisons of THC
limits
Our recommendation for THC limits in hemp foods and cosmetics
is 20 ppm.
Current Canadian legislation sets Canadian limits at 10 ppm, and
the Health Canada
report erroneously determined that even this amount was
dangerous. The hemp
oil available in Canada before industrial hemp was legalized
(from Don
Wirtshafter’s Ohio Hempery, for example) had 15 ppm and was
rejected by Health
Canada.
Switzerland is the only country other than Canada to set
limits on the THC in hemp
foods. After careful scientific evaluation, the Swiss set limits
of 50 ppm for hemp
oil, with less restrictive limits for other foods and bodycare
products. In Europe, the
Swiss standard is thought to be liberal, the German standard (20
ppm) is considered
conservative. The Canadian standard of 10 ppm is considered
severe, and the “zero
tolerance” recommended by the Health Canada risk assessment
is considered
draconian
5.0 BENEFITS OF HEMP FOODS AND
COSMETICS
Health authorities typically do cost/benefit analyses of new
drugs, trying to
determine whether the benefits outweigh the toxic costs
associated with the drugs.
Health Canada has chosen not to pursue the “benefits”
portion of such analyses,
asserting that their mandate is only to identify possible risks
to the health of
Canadians. Of course, all drugs and all foods have health risks.
However, the
notable risks of aspirin or red meat are deemed insufficient to
warrant banning
these substances.
The risks of THC in hemp foods and cosmetics are practically
nil, as we have shown.
However, even if minor risks could be demonstrated, we would
argue that
depriving Canadians of the health benefits of hemp foods and
bodycare products
would constitute more of a threat to their health than
unregulated consumption.
The purpose of this paper is to refute the flawed conclusions
of the Health Canada
risk assessment. For that reason, we will not dwell excessively
on the virtues of
hemp foods and bodycare products, which are well-described
elsewhere (e.g.,
Conrad, 1997). Instead, we will briefly list some of their
abundant health benefits.
5.1 Benefits of
Hemp Foods
Hemp foods are made from the hemp seed, which is botanically a
nut. There are
two major components of the hemp nut, the oil and the nutmeat.
Hemp oil is
made by cold-pressing the seed; what’s left is the hempseed
“press cake,” which is
commonly converted to flour for hemp breads and similar foods.
The hemp nut
can be eaten whole, as it’s very nutritious and quite
tasty. Hemp foods have been a
dietary staple for millions of people in Europe for centuries and
for tens of millions
in China and other parts of Asia for millennia.
5.1.1 Hemp oil
Hemp oil has many desirable ingredients (Pate, 1999a), the
most important of which
are the essential fatty acids (EFAs), linoleic acid (Omega 6) and
linolenic acid (Omega
3). These fatty acids are present in hemp oil in the ratio of
3:1, which is the “optimal
ratio” for health benefits (Erasmus, 1993).
“The membrane (coating) of every cell in our body is
composed of oil.
It is this oil that acts as a superconductor allowing an
unimpeded flow
of the bio-electric currents that govern nerve, muscle, heart
and
membrane functions. The oil component of our diet normally
comes
from fresh, well stored seeds, nuts, vegetables, and a few
fruits. If the
oils in your diet are primarily of low quality, such as
supermarket oils
and fats that stay solid at room temperature, then the oil
coating on
your cells are going to have some of the insulating properties of
tar and
be a less than ideal conductor. Conversely, if the oils in your
diet are in
a pure, unadulterated form, the bio-electric current will flow
much
smoother, and all our bodily functions will be easier to
perform:
everything from the pancreas secreting insulin to keep our blood
sugar
levels balanced, to keeping our hormone system in check, to
alleviating the buildup of the heavy LDL cholesterol that plugs
our
arteries leading to heart disease and arterial sclerosis.
Pioneers in the
fields of biochemistry and human nutrition now believe
cardiovascular disease (CVD) and most cancers are really diseases
of
fatty degeneration caused by the continued over consumption
of
saturated fats and refined vegetable oils that turn essential
fatty acids
into carcinogenic killers. One out of two Americans will die from
the
effects of CVD. One out of four Americans will die from
cancer.
Researchers believe cancers erupt when immune system response
is
weakened” (Thorpe, 1999, p. 32).
If, however, cell membranes are constructed from “fats
that heal” the best of
which is hemp oil (Erasmus, 1993) the health benefits are
considerable. Perhaps
the primary benefit is the effect of the EFAs on the heart. Hemp
oil reduces the
level of bad cholesterol (LDL), reduces inflammation in blood
vessels, thins the
blood (by reducing platelet stickiness), and reduces blood
pressure. Thus,
hypertension is relieved and the risk of heart attacks and
strokes is reduced. The
chances of heart disease in general are significantly reduced. In
October, 2000, the
American Heart Association issued a recommendation that Americans
consume
foods with high levels of Omega 3 (Gorman, 2000); the most
balanced common
source of this EFA is hemp oil.
A second major benefit of hemp oil is a strengthening of the
immune system. It
inhibits tumour growth, kills bacteria (including staph), and
heals wounds
(Erasmus, 1993).
In summary, the EFAs in hemp oil are used to:
- construct cell membranes, which create and
carry electrical currents
- bring toxins within cells to the surface, where they can be
removed,
and deliver nutrients from
the cell surface
- facilitate recovery of fatigued muscles by delivering
oxygen,
producing hemoglobin, and
removing waste products
- strengthen the immune system, preventing
infections and allergies
- develop nerve cells in the CNS
- promote healthy liver function
- increase stamina, vitality, and calmness
- reduce inflammation, pain, and swelling in
muscles and joints
- promote production of prostaglandins, an important system
of
hormones related to health
The EFAs in hemp oil will beneficially affect (partial
list):
- AIDS
- allergies, asthma
- Alzheimer’s disease
- arthritis
- Attention Deficit and Hyperactivity Disorder
(ADHD)
- cancer
- cellulite, aging spots, cataracts
- chronic fatigue syndrome
- cystic fibrosis
- diabetes
- dyslexia
- endometriosis
- enlarged prostate
- fibrosystic breast disease
- hair loss in men
- heart disease, hypertension
- lupus
- mental disorders: bipolar depression disorder,
schizophrenia
- multiple sclerosis
- obesity
- PMS
- stroke
- tuberculosis
- ulcers, constipation, diarrhea, digestive
problems
- violent personality disorders
- yeast infections
5.1.2 Hemp nuts, hemp
flour, and hemp protein
When the oil is squeezed from hemp seed, the remaining press
cake is made into
flour for hemp breads, pastries, and other products. This press
cake contains two
high-quality proteins called edestin and albumin. These proteins
contain all eight of
the essential amino acids in highly favourable proportions, and
they are easier to
digest than the protein in soybeans and other foods. Like EFAs,
proteins are the
basic building blocks of the human body. There are few bodily
functions that are not
affected, in a positive way, by hemp protein.
The dehulled hemp seed (hempnut) is perhaps the best way to
ingest hemp foods.
The delicious hempnut contains not only the proteins mentioned
above, but also
the highly beneficial EFAs, better preserved in the nutmeat
matrix.
An interesting report has turned up on the use of hemp protein
to treat tuberculosis
in Czechoslovakia during and after World War II (Sirek, 1954). At
an institution for
children with TB, doctors had no medicine and very little food.
The doctors decided
to treat the children with hemp seeds, because of the protein
(edestin) in the
nutmeat. Edestin containes not only the appropriate amino acids
(including
arginine, essential for formation and growth of new tissue) but
also a wealth of
healthy enzymes. A total of 26 children were treated with a diet
of hemp seed, oats,
and cottage cheese. All 26 were cured or significantly improved,
and all grew to be
healthy young adults.
5.2 Benefits of
Hemp Bodycare Products
Hemp oils are used to make body lotions, soaps, and other
products that heal the
skin, restoring natural health and beauty. The essential fatty
acids (EFAs) that are
used by the body to build and maintain healthy body cells
(especially the
membranes) work directly on epidermal cells, entering the lipid
layers of dry skin
cells to replenish their oils (Ohio Hempery, undated).
The EFAs also repair skin damage, promoting healing in wounds
and burns, and
they are antibiotic. Research has shown that EFAs are effective
treatments for atopic
dermatitis, eczema, and psoriasis (Fitzpatrick, 2000).
6.0 CONCLUSIONS
Hemp foods and bodycare products are among the
healthiest substances that
humans consume. In their essential fatty acids and proteins, hemp
products
provide the basic building blocks that our bodies use to
construct cells and tissue for
healthy and efficient functioning.
Health Canada, in a draft risk assessment, has raised the
question of possible health
risks associated with 10 ppm levels of THC, the psychoactive
ingredient in hemp.
We have reviewed the relevant research and concluded that there
are no health
risks from low level doses of THC. None. There may indeed be
health benefits:
several studies have shown strengthening of the immune
system.
The Health Canada risk assessment is based on poorly-designed
research. Most of
the research showing possible health risks with THC ingestion
uses massive doses
of THC, far more than even those levels consumed by the heaviest
marijuana
smokers. Every study showing health risks has been discredited or
refuted; cannot
be replicated; or has been shown to be in error by a majority of
studies on a given
topic.
The appropriate risk assessment for hemp foods and cosmetics
would show that
there are no health risks, only benefits. We believe that the
current Canadian
standard, requiring less than 10 ppm THC in hemp products, is too
low; we have
calculated 20 ppm as sufficient to protect consumers from any
possible psychoactive
reactions (and even these reactions are not a health risk). But
with considerable
effort, the hemp industry has found it possible to prepare hemp
products with less
than 10 ppm, and is willing to accept that standard.
7.0 REFERENCES
- Abrahamov, A., Abrahamov, A. & Mechoulam. R. (1995). An
efficient new
cannabinoid
antiemetic in pediatric oncology. Life Sci., 56, 2097-2102.
- Adams, M. (1999). Comments on the Health Canada Risk
Assessment regarding
hemp cosmetics. Response of The Body Shop to the Health Canada
report.
The Body Shop International.
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D.E. (1995). The ontogeny
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