EATING MEAT MAKES YOU SICK
Editor's Note
The following article was written by medical specialists and therefore
contains technical terms. Nevertheless this article concisely summarizes the
results of a large number of current medical studies (see
references) in a form seldom found.
Risks incurred by consuming meat
In industrial countries, life-style diseases such as obesity, diabetes, high cholesterol, high blood pressure, heart disease, and cancers are widespread. There is an abundance of epidemiologic data showing that a vegetarian diet is associated with a lower risk for these diseases.
Nevertheless, meat, sausages and fish are still considered to be a part of the normal diet. The myth that these are especially healthy and valuable foodstuffs is still widespread. Many members of the medical profession also still believe that meat is a vital force in your diet.
In modern epidemiological models, the public health risk of different diets is classified differently to those of a few centuries ago. A low intake of vegetable foodstuffs is now considered a risk factor for phytochemical deficiency diseases, including many tumor diseases, cardiovascular disease and degenerative diseases.
The following presents factual data demonstrating that meat consumption
is connected with considerable health risks. This information is based on
scientific publications available in the Medline database, either as
abstracts or original works.
Bone diseases
- Meat products contain on average more phosphorus than calcium, as
opposed to vegetable food. A raised dietary phosphorus/calcium ratio
leads to secondary hyperparathyroidism. (1)
- Parathormone from the parathyroid gland leads to a mobilisation of
calcium from the bones. Adolescents are at particular risk for this, as
insufficient bone mass in puberty is a risk factor for osteoporosis in
later life. A study of young women showed a negative correlation between
protein and phosphorus intake and radial bone thickness. (2)
- Animal proteins contain more sulfurous amino acids than vegetable
proteins. Protons resulting from the degradation of sulfurous amino
acids are a major source of acid. A continuous excess of acid promotes
the demineralization of the bones, since H+ ions bind to phosphate ions
during formation of hydrogen phosphate.
- In 2001 several studies were published on “acid-base metabolism” and
bone metabolism (3, 4, 5).
- A Swiss research group at the University of Lausanne showed that an
acid forming diet increased the excretion of calcium by 74 %, compared
with an alkaline forming diet.
- In a study of osteoporotic fractures, a research group from the
University of California published results showing that the risk of a
hip fracture in post-menopausal women essentially depends on the
composition of their diet. Older women with a high intake of animal,
rather than vegetable, proteins ran a significantly higher risk for hip
fractures than people in a control group. The incidence of hip fractures
in individual countries correlates with the ratio of animal to vegetable
protein in the daily diet. These researchers concluded that a low-grade
metabolic alkalose is probably the optimum acid-base status.
- The Framingham Osteoporosis Study also showed that a high consumption
of fruit and vegetable had a protective effect on bone structure (6).
Rheumatic diseases
- All animal products, especially meat, sausages and fish, contain
abundant arachidonic acid. Prostaglandins and leukotriens belong to the
metabolites of arachidonic acid. An increase in prostaglandin E can be
detected in the synovial fluid of people who suffer from rheumatism. It
also contributes to the development of cartilage erosion (7).
- The more arachidonic acid is ingested in the diet, the more
inflammatory substances can be produced. There are several publications
on the anti-inflammatory and analgetic effect of a vegetarian diet on
rheumatism (8, 9).
- A vegan diet is evidently particularly effective here since no
arachidonic acid is ingested.
Tumor diseases
- Frying, boiling and grilling of meat and fish produces heterocyclic
amines. These substances result from a chemical reaction between the
amino acids and the creatine of the muscular substance. Several studies
have shown that heterocyclic amines have considerable genotoxic and
mutagenic potential (10, 11).
- Heterocyclic amines are a risk factor for several tumor types, in
particular for colon carcinoma. Cancers of the stomach, esophagus,
prostate, pancreas, kidney and breast have also been associated with
heterocyclic amines within the medical literature (12).
- Uruguay and Argentine belong to the countries with the highest
consumption of beef and suffer also from the highest rates of cancer of
the breast and of the colon. Some studies also report a cardio toxic
effect of heterocyclic amines (13, 14, 15).
- In addition to heterocyclic amines other carcinogenic substance are
produced in the intestine during the digestion of meat. A study by the
University of Hohenheim found that a diet high in fat and meat increases
the toxicity of fecal water to the intestinal epithelia (16).
- Protein degradation by flora within the colon also produces
potentially toxic substances, including ammonia, phenols, indols, and
amines, as well as N nitroso compounds and sulfide (17).
- A study at the University of Cambridge demonstrated a close
correlation between the formation of N nitroso compounds and the amount
of red meat consumed (18).
- Epidemiological studies have demonstrated a correlation between the
consumption of red meat and the incidence of colorectal carcinoma. Meat
protein also constitutes a significant substrate for bacterial
production of sulfide in the intestines. Sulfide compounds also
contribute to the development of colitis (19).
- Increased concentrations of the insulin-like growth factor I (IGF-1) promote the development of tumor diseases. In 2002 a study of the University of Oxford was published on the IGF concentrations in different diet types. Vegans had significantly lower IGF-1 concentrations than meat-eaters and lacto-ovo vegetarians. In addition, the concentrations of IGF binding proteins (IGFBP-1 and IGFBP-2) were increased in this group. (20).
Hypercholesterinemia
- Since vegetable foodstuffs are nearly cholesterol free, the intake of
cholesterol via nutrition results from the consumption of animal
foodstuffs.
- Endogenous cholesterol production is regulated via the
insulin/glucagon ratio. Test persons with increased cholesterol
concentrations were also shown to have a higher insulin/glucagon ratio
than test persons with normal cholesterol values (21).
- The composition of dietary proteins influences the release of the
metabolism hormones insulin and glucagon. Animal proteins stimulate the
release of insulin and activate HMG-CoA reductase, the limiting enzyme
for cholesterol synthesis.
- Vegetable proteins usually contain more arginine than lysine. Animal
proteins on the other hand contain more lysine and leucine than
vegetable proteins. A cholesterol-lowering effect, especially of soy
protein, was demonstrated in several studies, which was mainly
attributed to the high arginine concentration of this vegetable protein
(22, 23, 24).
- A high intake of lysine in form of animal proteins increases the
incorporation of arginine into atherogenic apoproteins, such Apo E.
These proteins are transport molecules for fats such as cholesterol.
Some studies report a report a more favorable HDL/LDL ratio in
vegetarians (25, 26, 27).
- The LDL cholesterol of vegetarians has proved less susceptible to oxidization than that of non-vegetarians. This is attributed to the high intake of antioxidant substances by vegetarians.
Diabetes mellitus
- The fatty acid pattern of cell membranes, which is essentially
influenced by the dietary intake of fatty acids, exerts a considerable
effect on the sensitivity of insulin receptors.
- Meat and sausages contain a relatively high number of saturated fatty
acids. Several studies have shown that a high intake of saturated fatty
acids reduces insulin sensitivity and promotes insulin resistance
(29-32).
- The Western diet with its high intake of fat and saturated fatty
acids is a considerable risk factor for insulin resistance and type 2
diabetes. It is well-known that insulin resistance leads to
hyperinsulinism. Chronically raised insulin levels are a risk factor for
cardiovascular disease and for various kinds of tumors.
- The adherents of the Atkins diet (plenty of meat and fat) claim that
the advantages of this diet are due to a diminished insulin response
which facilitates weight reduction. In fact, food rich in protein leads
to an above-average insulin response surpassing its glycemic index (33).
Iron and oxidative stress
- Iron is one of the essential trace elements. About 70% is contained
in the blood pigment hemoglobin and in the muscle pigment myoglobin.
Many significant metabolism enzymes are iron dependent, which is why a
lack of iron should be prevented.
- In 1992 a connection between increased iron reserves and a 2.2 fold
increased risk for cardiac infarction was first described. This finding
has been confirmed by other studies (34, 35).
- Heme iron from red meat is resorbed ten times as well as iron of
vegetable origin. There is a positive connection between the risk for
cardiac infarction and the intake of heme iron. Excess iron forms free
radicals and damages LDL via oxidative stress. Oxidative damage to LDL,
on the other hand, is the most important pathogenetic principle for the
formation of foam cells and atherosclerotic plaques.
- A well-balanced vegetarian diet does not lead to a lack of iron.
Vegetarians, as a rule, have lower iron reserves, which according to a
recent study results in a higher insulin sensitivity (36).
Psyche and cortisol level
- A diet rich in protein leads to a rise in cortisol in the saliva and
in the blood serum. A diet rich in carbohydrates does not have this
effect (37, 38, 39).
- Hypercortisolism not only has an immune suppressive effect but can
also over time damage hippocampal cells which are important for memory
formation and for learning behavior (40).
- A diet with a greater emphasis on carbohydrates has a favorable
effect on the formation of serotonin in the brain. A sufficient supply
of serotonin improves mental health.
BSE and immune reactions
- Just two years ago the »BSE« issue caused considerable agitation
among the public. BSE has disappeared from the headlines since so-called
risk material now has to be removed during slaughtering and BSE tests
are compulsory by law. To date, the meat (i.e. muscle) of slaughtered
cattle has been classified as not harmful to health.
- This supposition must be questioned since the finding of the Nobel
Prize winner Stanley Prusiner that considerable amounts of prions are
present in the muscular system of infected mice. In March 2002 there was
a startling publication on this issue in one of the most renowned
scientific journals, the »Proceedings of the National Academy of
Sciences« (41).
- At the 7th Congress on Infectious Diseases and Tropical Medicine,
the Berlin Robert Koch Institute presented a study on golden hamsters.
The prion agent causing scrapie added to the hamster’s food was found in
concentrated amounts in all muscle tissues examined (42).
- On January 23, 2003, the news programme »Monitor« broadcast an
interview with the Munich neuropathologist Prof. Hans Kretschmar who had
repeated the tests of the Californian scientists on mice and also found
prions in muscle meat. Prof. Kretschmar called these findings quite
worrying, since an infection via muscle meat could not be excluded (43).
- As a consequence of the first known case of BSE in the USA several
scientific articles were published on December 23, 2003 questioning what
we know of this disease. United Press International (UPI) published a
long article on Creutzfeld-Jakob disease (CJD) on December 29, 2003. Up
until then, the classical form of CJD had been assumed to be unconnected
with BSE. Only the so-called variant form of this disease affecting
younger people had been connected with infected beef consumption.
- New research at the University of London has found that an infection
with BSE prions can cause the variant, as well as the classical, form of
CJD. In Switzerland numerous cattle have been BSE-infected in the past.
The incidence rate of CJD cases has doubled in the last three years.
CJD, like Alzheimer’s disease, is among the neurodegenerative diseases
which often cannot be clearly distinguished on the basis of the clinical
picture. Neuropathologists at several universities in the USA conducted
autopsy studies on people who had been diagnosed by specialists during
life as having Alzheimer’s disease. What makes these results so alarming
is that 3 to 13% of these cases were found to have not Alzheimer’s
disease, but Creutzfeld-Jacob disease.
- In the USA the number of people dying of Alzheimer’s disease
increased 50-fold from 1979 to 2000. In 2000, these amounted to no less
than 50,000 people. At present the number of people suffering from
Alzheimer’s disease in the USA is estimated at approximately 4 million.
Realistically one has to assume that the number of unknown cases of CJD
is high (44).
- On October 1, 2003 an interesting study by scientists of the
University of California was published in PNAS-online. The American
scientists had found out that after red meat consumption the human
metabolism incorporates certain sugar compounds denominated as
N-glycolylneuraminic acid (Neu5Gc) into various tissues. Neu5Gc
antibodies were identified in various subjects. This provided the first
proof that molecules from the ingestion of meat can generate an immune
response in the human metabolism. Regular ingestion of meat promotes
detrimental immune responses and can make the body more susceptible to
inflammation, with all the secondary diseases that ensue (45).
Environmental toxins
- About 90 % of all dioxins and furans are ingested via the consumption
of animal foodstuffs. Approximately half of them come from milk and milk
products. The concentration of persistent pollutants increases as they
move up the food chain. The final consumer may then ingest toxic amounts
of the pollutant.
- In almost every food scandal the fact is emphasized that no
toxicologically relevant concentrations were measured and therefore
there is no danger to the public.
- Many environmental toxins are substances that have a hormonal or
anti-hormonal effect on organisms (endocrine disruptors). In 2002 two
studies of the University of London were published showing that several
xenooestrogens combined had a considerable hormonal effect. Each of
these substances alone had a concentration below NOEC
(No-observed-effect concentration) (46, 47).
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(42) FAZ.NET, 8. April 2003
(43) WDR Monitor, 23.01.2003
(44) Mad Cow: Linked to thousands of CJD cases? By Steve Mitchell, United Press International, Published 12/29/2003
(45) Proc.Natl. Acad. Sci. USA, 10.1073/pnas.2131556100
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Source
Ärztegesellschaft zur Förderung der vegetarischen Ernährung
(Physician’s Society for the Promotion of a Vegetarian Diet)
Löwensteinstrasse 7
97828 Marktheidenfeld
Germany
http://www.fleisch-macht-krank.de
(German page)