Each week I put out an instagram post asking people if they have any questions on fitness and nutrition they would like answered.
One respondent asked: “What are your thoughts on red meat causing cancer.”
Well my thoughts are that I like red meat, and I hate chicken and fish. In fact, I avoid eating chicken and fish as much as possible and I stick to grassfed beef as my main protein source for a number of different reasons, but mostly because chicken and fish taste like chalk to me.
Let me get back to answering the question: does red meat cause cancer?
The answer is going to be a lot more confusing than you would like: yes and no. Yeah, a lot of you would like me to come up with a simplified rule for you to follow, but the reality is that that’s not the way science works and most things do not fit into our little neat versions of the world.
Let’s get into the no part first. There is nothing particularly evil that is in red meat that would lead to cancer growth when all factors are controlled for. A recent meta- analysis of 27 different independent perspective cohort studies found that the association between red meat and cancer growth disappeared once they analyzed and controlled for factors beyond eating meat versus not eating meat. These included processed meats versus non-processed meats, overall caloric intake, smoking, and drinking. Processed meats are defined as meats with added nitrates like bacon, ham, beef jerky, and hot dogs. As I’ve mentioned before in other blogs, meta analyses are particularly powerful in seeing where the science is going because they pool smaller studies into larger studies for increased statistical significance.
The bottom line is that if you take a healthy person who avoids smoking, drinking, and who eats a moderate calorie diet of fresh meat and whole foods, red meat would not cause that person to get cancer according to this study.
Here, on the other hand, is the yes part. What you should be concerned with is your overall animal protein intake. A study from the University of Southern California from 2014 found that high protein diets were as deadly as smoking in causing cancer in patients aged 50 to 65. Here, a high protein diet was defined as greater than 20% of total calories, and the association was strictly with animal protein. The idea is that increased consumption of protein leads to greater secretion of insulin like growth factor 1 (IGF-1) growth hormone, which can lead to higher risk of cancer.
Since many of you are probably eating 200 plus grams of protein per day as part of your fitness/bodybuilding regimens, this is something you should take note on. As I have written before in my blog on protein, there is no good reason to eat more than 0.5 grams of protein per pound of bodyweight to gain muscle, and anything over 0.75 grams of protein is massive overkill for building muscle.
As many of you know, I advocate a high fat ketogenic diet. Many inaccurately associate this type of diet with high protein intake. The ketogenic diet is actually a moderate protein diet with under 20% of calories coming from protein. This is because higher protein levels than this can cause a conversion of protein to glucose and throw you out of ketosis.
The bottom line: if you like red meat, eat it, but keep your overall protein intake to moderate levels. You can still reach your strength and aesthetic goals with lower protein intakes, and it will be much better for your overall health.