Cancer Promotion-The Reversible 2nd Phase?


During the initiation phase we have seen how animal protein increased the level of enzyme activity and increased the amount of DNA altering aflatoxin, which is available to attack cell DNA. But what is the affect of protein intake during the important promotion phase, which is sometimes called the reversible phase? To find out Dr Campbell induced cancer into the liver of rats using aflatoxin. He then varied the amount of animal protein consumed from a high of 20% of calories about the amount of the male American diet to a low 5% of calories. Other scientists discovered that little microscopic cell clusters called foci occurred after initiation, which were a precursor of, and predictor of full-blown tumors. This development, cut decades and  prohibitive cost from the lab experiments. However the final laboratory experiment was based on actual tumor development in a massive rat study.

They varied the amount of aflatoxin given to the rats and found that it was the animal protein consumption rather than the level of aflatoxin that caused tumor development. They discontinued all protein consumption for periods of time, which caused tumor development to stop. They then turned tumor development back on by restarting high levels of animal protein consumption. Up to this time they used the casein in cows milk as their source of animal protein. They then switched to plant protein and looked at other animals. The reader can only get a sense of the thoroughness of the lab animal phase by reading the full chapter #3 “Turning off Cancer”. But it was becoming clear to Colin Campbell that in lab animals a pattern was beginning to emerge: nutrients from animal foods increased tumor development while nutrients from plant food decreased tumor development in the large lifetime study of rats with aflatoxin induced tumors. They had completely confirmed the Indian studies, which prompted the research.

At this point a scientist from Mainland China came to work in Dr. Campbell’s lab. This relationship was to lead to the largest human study of the role of nutrition and lifestyle in most major diseases in the largest and most comprehensive manner ever undertaken. They went on to the China Study.



Leave a Reply

Fill in your details below or click an icon to log in: Logo

You are commenting using your account. Log Out /  Change )

Google photo

You are commenting using your Google account. Log Out /  Change )

Twitter picture

You are commenting using your Twitter account. Log Out /  Change )

Facebook photo

You are commenting using your Facebook account. Log Out /  Change )

Connecting to %s

%d bloggers like this: