Biological Magnification, Cancer & Degenerative Disease

[Guest guest]

Biological Magnification

 

Animals are known to concentrate environmental pollutants i.e.,heavy

metals,pesticides,herbicides and industrial toxins in their gut.

 

These toxins become concentrated in the tissues of organisms as they

pass through the food chain.

 

The concentrating process is called biological magnification and is

responsible for widespread decimation of animal life on earth.

 

Moreover, if species are harvested for human consumption from the

top of the food chain, then these concentratedtoxins

are transferred to the human consumer. The extent of biological

magnification of toxins such as DDT is well documented, and it has

been

shown that the concentrating potential can induce several million

fold

increases in the concentration of these substances in the tissues of

animals.

 

Concentrations of DDT in the water as low as 0.000005 parts per

million

can be concentrated to over 26 parts per million in top carnivores.

 

Animals accumulate toxins particularly in their fatty tissues, and

when

called upon to utilize their fat reserves, the release of these

toxins

into the bloodstream can lead to various diseases and death.

 

Within the gut, the limited availability of carbohydrates in high-

meat diets will lead to an increase in ammonia concentration in the

colon because bacteria will metabolize the protein residues which

enter the gut when carbohydrate levels are low.

 

Ammonia, in turn, increases cell proliferation and alters DNA

synthesis and

has, therefore, been implicated in colon cancer.1 It is known

thatincreased cell proliferation is associated with cancer in humans

 

Ammonia will not only be liberated from animal proteins, but from

excessive intake of plant proteins as well.

 

A high plant-protein intake is, however, usually associated with a

highfibre intake and this would shorten the 'exposre time.

 

This is particularly true in the case of whole foods with their high

concentrations of fibre. High ammonia levels are not only a problem

withthe gut, but also effect the whole organism.

 

As discussed in the section on proteins, the consumption of high

levelsof proteins will necessitate the deamination of amino acids in

orderto

meet the body's energy demands.

 

This will require efficient detoxification of the produced ammonia,

which in mammals is achieved via the urea cycle.

 

As the amino acid arginine plays a principle role in this cycle, the

higher level of this amino acid in plant proteins than in animal

proteins offers a possible protection against ammonia toxicity.

 

Not all the animal protein ingested is completely digested, and

approximately 2g of nitrogen in the form of undigested protein,

peptides and aminoacids (equivalent to 12 g of protein) enter the

large bowel daily.

 

The bacteria in the large bowel would prefer to utilize carbohydrate

residues to meet their energy needs, but when carbohydrate levels

are

low and protein levels high, then amino acids are bolised resulting

inthe release of ammonia and phenol, both of which are potentially

harmful.

 

Cooked and smoked meat products, in addition contain other

potentially harmful substances (such as polycyclic aromatic

hydrocarbons, heterocyclic amines, and N-nitroso compounds) which

have been linked to degenerative diseases.

 

These potentially harmful substances should be eliminated from the

system as rapidly as possible, and if sufficient fibre were present

in

the diet, then the time that food is retained in the intestines

would beconsiderably reduced.

 

In the case of a relatively high intake intake of cereal fibre, the

partly fermented residual polysaccharides, derived from these

fibres,

would absorb water, and this would lead to increased fecal mass and

decreased transit time, thus reducing the time that potentially

harmfulsubstances such as carcinogens remain in the large bowel.,

[ii]

With a high meat consumption, however, the harmful substances can

remainin the intestines for much longer periods, and this exposure

hasbeenlinked to increased cancer rates. In this regard, the

relationship

between colorectal cancer and meat consumption is well established.

Colorectal cancer is the second most prevalent cancer in Western

societies and affects up to 6% of men and women by the age of 75.

Phenols

A high-meat, low-carbohydrate diet will also allow more aromatic

aminoacids, such as phenylaline and tyrosine to enter the colon.

Gut bacteria produce cresol and phenol when they metabolize these

aminoacids. Both cresol and phenol have been associated with the

promotion ofskin and colon cancer[iv] and rapid elimination of these

compoundsseemsadvisable, even if their effect on the gut mucosa has

not been fullyresolved.

A diet rich in fibre can once again assist in clearance of these

compounds by decreasing the food transit time.

Amino acid metabolism will also increase the concentration of these

compounds in the blood, and elimination of these compounds is

normally

done by the kidneys.

Nevertheless, consistently high levels of these compounds can be

associated with diets rich in animal products, as it is known that

urinary phenol levels increase when subjects are fed high-meat diets

and

to decrease with an increase in dietary fibre.

Low phenol levels could thus limit the risk of cancer, and a whole-

fooddiet is ideal to achieve both low levels of these compounds and

highlevels of fibre.

Polycyclic Aromatic Hydrocarbons

Polycyclic aromatic hydrocarbons (PAH) result primarily from

atmospheric

deposition onto plants in smoky areas. One such hydrocarbon is

Benso(a)pyrene, a potent carcinogen, which is also formed in

foodstuffsthat are smoke-dried (such as tea) and also during the

smoking andgrilling of animal foods.

PAH also occur in shell-fish that come from a polluted marine

environment.[vi]

Fats are once again a prime source of PAH and smoked and grilled

food in

particular are subject to contamination by these carcinogens.[vii]

Avoidance of high risk foods seems desirable if the risk from these

compounds is to be curtailed.

Heterocyclic Amines

Heterocyclic amines are mutagenic and carcinogenic compounds that

areformed in cooked and charred foods.7 They form particularly in

meat evn if cooked at relatively low temperatures.

In fact, it is estimated that the average consumption of

these

compounds is as high as 100 µg per person per day,[ix] but other

calculations place daily consumption in the range of 0.4 to 16

µg/day.

Heterocyclic amines have been found to elicit carcinogenicity in the

liver, lung, oral cavity, stomach and intestines of rats and mice,

and

have also been implicated in cancer of the lymphatic systems, blood

vessels, skin and mammary glands.

Over 20 mutagenic heterocyclic amines have been isolated from cooked

animal products, and well done portions of meat contain higher

concentrations than medium or rare portions.

To obtain these compounds for experimental purposes, a standard

protocol

of grilling or frying for 6 min. at 200 °C is used.

Generally, frying, grilling and barbecuing produce more of these

compounds than does stewing, steaming, microwaving or poaching.10

Heterocyclic amines are relevant carcinogens in humans, but in the

caseof colon cancer their relative contribution may be small (0.25%

ofallcolon cancers).10

Food that will be particularly suspect in terms of heterocyclic

amineswill be cured and baked or fried meats.

Even beer, soybeans, protein isolates and fried mushrooms were found

tocontribute significantly to the daily intake of these compounds.

A study of heterocyclic amine formation in swine meat heated to 200 °

Cshowed that the main reactants of the mutagen-forming reactions are

amino acids and creatine.[xi]

N-Nitroso Compounds

These compounds have been linked to human cancer of the oesophagus,

stomach, bladder and possibly lung.[xii]

Beer as well as nitrite-cured meat products, especially bacon after

frying, and salt-dried or smoked fish, are major sources of these

compounds.

Incidentally, the mainstream smoke from one cigarette contains up to

65µg volatile nitroso amines and the side stream contains up to 1000

µg,8a healthy lifestyle thus constitutes more than just eating

correctly.

It is difficult to estimate what the level of exposure to these

compounds is, particularly since it is known that nitroso amines are

efficiently metabolized in the liver.

Nevertheless, these compounds have induced liver and oesophagus

cancerin experimental animals. Intestinal bacteria can also catalyse

theformation of nitroso amines and this has been linked to gastric

cancer.

Nitrosated amides are direct acting carcinogens, and cause tumours

near

to the site they are produced, whereas nitrosated amines require

hydroxylation and can initiate tumours near to the site they are

produced, whereas nitrosated amines require hydroxylation and can

initiate tumours at distal sites.10

In one study, increased consumption of red meat caused a 3-fold

increase(from 40 to 113 µg/day) in N-Nitroso compounds in the faeces

ofeightvolunteer males who were subjected to low and high meat diets.

The increase is high, when one considers that smoking 40 cigarettes

aday produces an exposure to approximately 30 µg/day of tobacco-

specific

carcinogenic N-Nitroso compounds.[xiii]

Biological Magnification

In addition to the aforementioned compounds, animals are also known

toconcentrate environmental pollutants such as heavy metals,

pesticides,herbicides and industrial toxins.

These toxins become concentrated in the tissues of organisms as they

pass through the food chain.

The concentrating process is called biological magnification and is

responsible for widespread decimation of animal life on earth.

Moreover, if species are harvested for human consumption from the

top ofthe food chain, then these concentratedtoxins

are transferred to the human consumer. The extent of biological

magnification of toxins such as DDT is well documented, and it has

been

shown that the concentrating potential can induce several million

fold

increases in the concentration of these substances in the tissues of

animals.

Concentrations of DDT in the water as low as 0.000005 parts per

million

can be concentrated to over 26 parts per million in top carnivores.

Animals accumulate toxins particularly in their fatty tissues, and

when called upon to utilize their fat reserves, the release of these

toxins into the bloodstream can lead to various diseases and death.

www.geocities.com/mrsjoguest/Diets

_________________

JoAnn Guest

mrsjoguest

www.geocities.com/mrsjoguest/Genes