I am almost through with the book.
The information will definitely make you take notice. This was touched on briefly in another thread. In particular, the main claim is that animal protein, and not plant protein, promotes cancer. More specifically, after the process by which a chemical carcinogen initiates cancerous change, a diet high in animal protein causes promotion, and consequently progression.
According to the book, studies used mice who were fed either 20% of daily calories from protein (specifically, casein) or 5% of daily calories from casein. The group of mice were treated with a very potent carcinogen known as aflatoxin, derived from mold which grows on peanuts.
100% of the experimental group animals (those with 20% of their daily calorie intake coming from casein) developed liver cancer.
0% of the animals who derived 5% of their daily calories from casein developed liver cancer.
Mice fed diets which supplied 20% of the calories from SOY PROTEIN or WHEAT PROTEIN showed very little foci development (early liver cancer stage.)
This is indeed baffling. They did not test any other proteins besides casein.
The exact mechanism was briefly touched on but it was not thoroughly explained for my liking. Basically all it said was that high animal protein intake upregulated a complex of enzymatic machinery known as Multi Function Oxidase, I believe. As a result of the high protein intake, for whatever reason, this enzyme system becomes highly active. This enzyme system is responsible for taking a procarcinogen, like aflatoxin, and modifying it in the body, resulting in a much more reactive carcinogen which can then go on to form complexes with DNA called adducts. This is, in effect, the cellular damage which ultimate results in malignant change over time.
They also experimented with mice infected with Hepatitis B virus, which normally greatly increases the chance of liver cancer.
Diets of 22% calories coming from casein resulted in intense liver cancer development, while less was observed at 14% and none was observed for 6%. High intakes of animal protein turned on the viral gene of HBV causing cancer.
I’m almost done with the book, but not quite finished. I would definitely like to discuss this is more detail.
Why were there no other animal proteins tested?
What is it specifically about animal protein that could actually cause this? Other than the amino acrid contents of proteins, with individual amounts of amino acids varying by protein to protein, what else could there be? Is there something “else” in animal protein other than the amino acids which causes this?
I gotta go now. Good topic though. I’ll be checking back in later.