"Eggs, Choline, and Cancer"
Two million men in the U.S. are living with prostate cancer,
but that's better than dying from prostate cancer.
Catch it when it's localized and your 5-year survival
is practically guaranteed,
but once it really starts spreading
your chances drop to 1 in 3.
Thus, identification of modifiable factors
that affect the progression of prostate cancer
is something that deserves study.
So Harvard researchers took more than a thousand men
with early stage prostate cancer,
followed them for a couple years to see if there's anything
in their diet associated with a resurgence of the cancer,
such as spread to the bone.
Compared to men who hardly ate any eggs,
men who ate even less than a single egg a day
had a significant 2-fold increase
in the risk of prostate cancer progression.
The only thing worse was poultry consumption–
up to 4 times the risk of progression
among high risk men.
They think it might be the cooked meat carcinogens—
the heterocyclic amines that for some reason
build up more in chicken and turkey muscles than in other meats.
But what about the eggs?
Why would less than once a day egg consumption
double the risk of cancer progression?
It may be the choline.
"A plausible mechanism that may explain the association"
"between eggs and prostate cancer progression is high dietary choline."
Egg consumption is a determinant
of how much choline you have in your blood,
and higher blood choline has been associated
with a greater risk of getting prostate cancer in the first place.
So the choline in eggs may both increase
one's risk of getting it and then having it spread,
and also having it kill you.
"Choline intake and the risk of lethal prostate cancer."
Choline consumption associated with not just getting cancer and spreading cancer,
but also significantly increased risk of dying from it.
Those that ate the most had a 70% increased risk
of lethal prostate cancer.
Another recent study found that men
who consumed 2 1/2 or more eggs per week—
that's just like one egg every three days--
had an 81% increased risk of lethal prostate cancer.
Now it could just be the cholesterol in eggs
that's increasing fatal cancer risk,
but it could also be that choline.
Maybe that's why meat, milk, and eggs
have all been associated one time or another with advanced prostate cancer,
because of the choline.
In fact, choline is so concentrated in cancer cells,
if you follow choline uptake you could track
the spread of cancer throughout the body.
But why may dietary choline increase the risk of lethal prostate cancer?
Remember, dietary choline is converted in the gut
into trimethylamine,
and so the Harvard researchers speculated
that the TMAO from the high dietary choline intake
may increase inflammation and this may promote
progression of prostate cancer to lethal disease.
In the New England Journal of Medicine
that same Cleveland Clinic research team
that did the famous study on carnitine, repeated the study,
but this time instead of feeding people a steak,
they fed people some hard-boiled eggs.
And just as they suspected,
a similar spike in that toxic TMAO.
So it's not just red meat.
And the link between TMAO levels in the blood and strokes,
heart attack, and death was seen even in low-risk groups
like those with low-risk cholesterol levels.
So eating eggs may increase our risk regardless
what our cholesterol is, because of the choline.
It's ironic that the choline content of eggs
is something the egg industry actually boasts about.
And the industry is aware of the cancer data.
Through the Freedom of Information Act
I was able to get my hands on an email
from the executive director of the industry's Egg Nutrition Center
to an American Egg Board executive
talking about how choline may be a culprit
in promoting cancer progression:
"Certainly worth keeping in mind as we continue"
"to promote choline as another good reason to consume eggs."