Eat, drink, smoke – no problem

In March this year, there was yet another feast of ignorance, but I could not bring myself to address it until now.

It was reported at that time that “about two-thirds of cancers are caused by random typos in DNA that occur as normal cells make copies of themselves”. 

The report was based upon a "reiterated" research paper by B. Vogelstein.and his mathematician C. Tomasetti. The “finding” supposedly explained why healthy people still get cancer. In other words, no matter how diligently you take care of yourself and how healthy your lifestyle is, you can still develop cancer. 

This part is TRUE. All of us have cells that divide (i.e., replicate), and mistakes are introduced in cells’ DNA during replication. These mistakes may turn out to be mutations that can drive cancer development.

However, the esteemed researchers did not elaborate on the other side of the story: if you do not put any effort into being and staying healthy, if you are obese, physically inactive, smoke and drink, then you do have a HIGHER chance of developing cancer.

The two researchers estimated that 66 percent of mutations in cancers resulted from copying errors (during replication), the rest were due to lifestyle, environmental factors, and inheritance.

What the researchers COULD NOT AND DID NOT estimate was how many replication-introduced DNA errors were eliminated in some people, and therefore, these people NEVER developed cancer. Remember, individuals who lead a healthy lifestyle have also a healthy immune system that eliminates many of the cells with mutations (i.e., DNA errors). Many mutations are also “intercepted” by additional control mechanisms, and the cells can either repair the mistakes in the DNA or kill themselves (i.e., the cells commit to apoptosis).
 
Therefore, a better question that the researchers could have pondered was, why the DNA mistakes are sometimes not “addressed” by the control mechanisms. The esteemed researchers did not discuss that some DNA mistakes are not corrected/addressed by the natural control surveillance mechanisms simply because people have unhealthy lifestyle: eat too much sugar, become overweight/obese, stress out, do not move too much, drink and smoke, etc.

But then isn’t it more interesting to say one side of the story and fatalistically conclude that “most cancers are due to bad luck”?  After all, the words "bad luck" make a much more interesting title.

By the way, the fact that our DNA replication machinery is not perfect has been known for a long time. There is a silver lining to this imperfection – if there were no changes introduced in the DNA, we would not have had evolved from apes to whatever we think we are today.

Here are some comments that appeared after the quoted above article:

“…well that makes us all feel better now we know that its just bad luck”

“…Sounds like the "cancer prevention" industry - which is massive is busy spinning the truth!”

“…Genetics are the key factor. It basically refutes the diet fanatics, and their bleeting about health benefits of certain diets.”
 
The  comments are a prime example of how general public education marches on!