There are countless times I’ve heard personal trainers and health gurus say that eating many small meals throughout the day is optimal for weight loss.
I’ve never really bought it, since it doesn’t make much sense that metabolism would be elevated just because the digestive system is running all day.
Two half chickens take just as much energy to digest as a whole chicken, right?
The steady blood sugar argument doesn’t hold either, since a healthy body is perfectly capable of maintaining optimal blood sugar levels.
Well, it appears that eating too often may have a really nasty side effect.
Eating often. Both inconvenient and raises your chances of colon cancer
The Colon
The colon is close to the end of the digestive tract. Food first passes through the mouth, then through the esophagus to the stomach. From there, it goes through the small intestine to end up in the colon.
After leaving the colon, it passes through to the rectum and… well, that’s when the yucky stuff happens.
The function of the colon is mainly extracting water and minerals from feces, and there are tons of bacteria in there that help ferment unabsorbed material from the diet.
Cancer of the colon or rectum, also known as colorectal cancer, is the third most commonly diagnosed cancer in the world and a significant cause of death (1).
Anything that drastically increases the risk of colon cancer is not to be taken lightly.
Eating frequency and colon cancer
When I started writing this post, I had planned on examining eating frequency and its effect on weight loss.
However, during my research I found something much more interesting.
I found several studies showing how frequent eating can increase risks of colon cancer.
In one of the studies, men who ate 3-4 meals per day had almost double the chances of developing colon cancer compared to those eating less than 3. More than 4 meals per day carried no additional risk over 3-4 meals. There was no correlation with meal frequency and colon cancer in women in this study (2).
Another one discovered that eating snacks (small meals between meals) increased chances of colon cancer by 60% per snack, while eating meals (breakfast, lunch and dinner) didn’t increase the risk (3).
In the third study I found, those who ate 3 meals per day had a 70% greater risk of colon and 40% greater risk of rectal cancer compared to those who ate only 2 meals. For 4 meals or more per day, the elevated risk was 90% for both colon and rectal cancer (4).
Conclusion
This is an example of when blindly following conventional wisdom advice can lead to negative outcomes.
The researchers believe that the increased risk of colon cancer may be due to frequent eating causing regular release of bile acids, which can be carcinogenic in excessive amounts (4).
I examined the effect of meal frequency on weight loss and it appears that it has a very small effect, but I believe this is probably due to the fact that those who tend to eat more frequently are more “health conscious” and therefore less likely to be overweight.
Personally, I’d rather have a few extra pounds than get colon cancer. No point in being lean if you’re dead.
I am not really sure if we every ate as often and as much as we do now. America is the land of plenty, I would think that would include poor health. This is because pre-packaged items are dishonesty sold as food. Both the amount and quality are the real issue.
I agree with you don’t follow a trend without some research.
Well said. If we want to use the evolutionary perspective then I don’t believe that humans in the past ate so many meals per day. I can imagine that hunter-gatherers would rather eat lightly or fast during the day while eating a big meal in the evening, after the hunt.
Hey Kris,
great post man! ;-)
Folks are lucky to find someone like you who applies some proper medical background knowledge and even scientific studies to their material: talk about useful!
I would like to add that high meal frequency or “grazing” is simply a good method of increasing the odds for overeating anyways.
And most will have heard by now of all the exceptional health benefits short term fasting can have not only on leanness but on overall health too!
Somewhere between 1-4 meals a day seems to make the most sense, both from a convenience as well as a hormonal standpoint!
Good Job man, keep up the great work!
Mark
Thanks for the comment, Mark :)
Yea this is definitely another good reason to do short term fasting, it’s something that I used to do a while back after reading a lot of promising research on it.
Interesting article and conclusion, however your point about the second study is misleading. You failed to mention the gender effect (i.e., only men were at risk for colon cancer, not women):
“Among men, participants in the lowest group of eating frequency had approximately half the risk of colon cancer compared with the middle group (adjusted OR = 0.53; 95% confidence interval, CI = 0.30-0.92). Compared with the middle group, men in the highest group had no greater risk of cancer (adjusted OR = 1.03; 95% CI = 0.74-1.44). No significant associations were detected among women. Decreased eating frequency was associated with a lower risk of colon cancer among men but not women.”
Thanks for pointing that out Avram, I appreciate it.
I have updated the post :)
Cool, great to see that you are open minded to feedback.
Where’s the studies in your research??
I would like to see the data before I am going to believe this article. And especially take a look at WHO did the research and conclusions on those studies.
I am not saying this is wrong but I think its best to have your references down before you make a claim on eating more frequently actually causes cancer but more importantly the FOOD you eat is what gives you the cancer.
Just sayin….
Wendi
Hello Wendi,
the studies are linked within the article, in the brackets (2), (3) and (4).