Are Eggs Really as Bad for Your Arteries as Cigarettes?
Mark’s Daily Apple
by Mark Sisson: Dear
Mark: Coffee and Insulin, Fat and Post-Workout Meals
This past weekend,
amidst all the Ancestral Health Symposium madness, I caught the
headline while flicking through my phone for a few brief seconds.
Didn’t open it up, though. Just cruised on past. I’d
hoped to just forget about it, to ignore it, to banish it to the
back of my mind where half truths and junk studies go to die. And
truth be told, I pretty much had forgotten about it until I checked
my email to find a ton of frantic emails from readers wondering
if their beloved and dependable egg yolk breakfasts were killing
them faster than the cigarettes they don’t smoke. What? You
EGG YOLKS ALMOST AS BAD AS SMOKING
(with less hysterical capitalization) “May increase carotid
So what are
we looking at here?
looking at a study in which a trio of researchers (two of whom with
ties to the statin industry) quizzed a group of middle-aged
and elderly stroke patients about their lifelong egg intake and
smoking history, making sure to stress the importance of accuracy
and honesty in their answers. Yes, you heard me right: they expected
people to remember every last egg they ever ate. Still, everyone
in the study was assumed to have supernatural memory, so I guess
it evens out.
Those who ate
the most eggs were the oldest – almost 70 years old on average,
compared to the relatively sprightly 55 year-old egg avoiders. It’s
pretty well accepted that with
age comes the progression of atherosclerosis, a process that
takes, well, time to occur. Plaque doesn’t just snap into
existence; it develops. All else being equal, the older you get,
the more plaque you’ll have.
Those who ate
the most eggs also smoked the most and were the most diabetic. To
their credit, the authors tried to control for those factors, plus
several others. Although they tried to control for sex, blood lipids,
blood pressure, smoking, body weight index, and presence of diabetes,
the study’s authors didn’t – couldn’t –
account for all potentially confounding variables. In their
own words, “more research should be done to take in possible
confounders such as exercise and waist circumference.” Hmm.
“Possible” confounders, eh?
reduces inflammatory markers of atherosclerosis.
even reduces markers of atherosclerosis in pre-pubertal obese children!
reduces thickness of the carotid arterial wall. It doesn’t
get much clearer than that. Exercise is a massively confounding
variable that the authors failed to take into account.
high waist circumference predicts atherosclerosis of the carotid
Or how about
stress, which also wasn’t considered?
daily psychological demands – the amount of crap you perceive
to be heaped on your plate – are associated with progression
of carotid arterial plaque.
not like the size of a person’s waist, whether or not they
move of their own volition or sit in an easy chair all day, and
how much stress they endure have any impact on their risk of developing
atherosclerosis. Those things may be linked, and I’m
sure the authors would have loved to include them in their analysis,
but there just wasn’t enough space on the questionnaire. Besides,
it’s not like a little physical activity and mediation could
even undo the damage wrought by 4.68 sinful egg yolks per week.
Why, that’s nearly a half dozen!
though, the subjects were all stroke patients who’d lived
to tell the tale. They’d been in contact with the medical
community (you generally don’t just shake off a stroke without
medical attention), who no doubt gave them the standard required
advice to prevent another event, which includes “a
reduction in saturated fat and cholesterol intake…and a boost
in physical activity.” Since the egg-eaters obviously
didn’t listen to their doctors’ recommendations to cut
back on cholesterol intake, I’d wager they treated the exercise
recommendations with similar levels of disdain. What do you think?
what I think: this is an observational study whose already limited
worth depends entirely on the memory of an inherently fallible creature
being infallible. As such, it cannot assign causality, contrary
to what the media (“Egg
Yolks Can Quicken Hardening of the Arteries“) and authors
(“It has been known for a long time that a high cholesterol
intake increases the risk of cardiovascular events”) say.
Furthermore, why single out egg yolks? I mean, I get it –
authors sort of have a vendetta against eggs – but what
about other foods? Were those even analyzed or asked about? What
about the stuff that people generally eat with eggs, like pancakes
and vegetable oils, or the foods that contain egg yolks, like baked
goods and mayonnaise? For all we know, egg yolk intake could have
been a marker for eating garbage; most people aren’t tossing
raw yolks into post-workout shakes, gently poaching eggs with coconut
vinegar, or horrifying co-workers with a bag full of hard-boiled
eggs like we Primals are wont to do. They’re getting Grand
Slams at Denny’s, eating bologna sandwiches with mayo on white
bread, and overcooking scrambled eggs in canola oil until they’re
the rest of the article
to Lew's recent podcast with Mark Sisson
August 16, 2012
© 2012 Mark's Daily Apple
Best of Mark Sisson