Wouldn’t that be nice? Imagine steak being proclaimed as a health food…as it once was. Sigh. Will those days ever return? Not if certain researchers have anything to say about it!
I’m sure that many of you saw the recent article in the NY Times about a study that showed the bacteria in our guts converts the carnitine found in red meat into an evil, deadly substance, and how this might be the reason why meat is responsible for heart disease.
The researchers argument was that our intestinal bacterial convert carnitine into a toxic substance called trimethylamine oxide (TMAO) in the liver which then may be the cause or one cause of atherosclerosis in humans. Earlier work by the two main researchers found that choline coverted to TMAO in mice genetically modified to get heart disease and are now extending this idea to humans via the carnitine found in red meat.
Not that red meat is the only food that causes such a conversion mind you. In another study researchers found that lots of the foods tested caused this conversion to happen including heart healthy vegetables. But as we all know, red meat is bad for us and veggies are definitley good for us. So, it’s the red meat that’s to blame!
Intestinal microbiota metabolism of l-carnitine, a nutrient in red meat, promotes atherosclerosis.
Wow. How damning. Is this really true? Does the study show that red meat promotes heart disease? And if so, just red meat? I can hear my doting mother in-law’s fingers banging away at the keyboard now composing an urgent email to make me stop eating steak:
My dear SON – please did you see it? The study by the doctors?! They know meat is bad now!! Please don’t eat meat anymore!! Love you Mom. PS – did the sweater fit?
As I see it, the idea itself is total nonsense for several reasons. For one, humans have been eating meat for, well, a very long-ish time. If eating meat didn’t kill us all off several hundred thousand years ago, why would we think that meat would try to kill us now? Hmmm. I know that is not a very scientific explanation but think about it.
For those of you who are religious and at the same time think that your evening steak is killing you, if you recall from your Bible studies God said we could and should eat meat. I have read the Bible and nowhere in it do I recall the big man tossing in any caveats about meat in general being deadly like:
Fear thou my children TMAO – a by-product of eating my fleshy creations and thus limit the amount you consume. The same goes for my plant matter creations but these are heart healthy so worry not!
It’s true that certain animals were forbidden to the Jews (but God never says why exactly). Still, meat is clearly on God’s menu for all of us. If it was so bad, why advise us to eat it? Food for thought for my religious brothers and sisters…
The unfounded bias against meat in the world of nutrition is, to me at least, shockingly blatant. It pervades the thoughts of virtually every nutritionist’s dietary recommendations. Statements like, “Even though there is no conclusvie evidence to support the idea that red meat or meat in general is harmful, common sense tells us to limit our intake of meat, especially red meat,” are rampant in popular nutritional press.
On page one of the study the researchers state:
However, a recent meta-analysis of prospective cohort studies showed no association between dietary saturated fat intake and CVD, prompting the suggestion that other environmental exposures linked to increased meat consumption are responsible
Yeah, OK, so the fat in meat is now found innocent in the court of nutritional law, but it’s STILL the meat that’s to blame. Of course, we should all feel free to go face down in vegetalbes as often as we like, even though studies have shown that peas produce far more of the supposed harmful, artery-clogging substances than meat. But vegetables are healthy for us so there can’t be any meaningful association there, right?
Again, research has shown that the cholesterol and saturated fats in meat can no longer be wrongly tormented as criminals to our health. You can see this fact for yourself here. But I don’t notice anyone apologizing for the years of false accusations and shunning tactics made about meat as if they were Amish children gone rouge. Why? Because there STILL must be something about meat that is bad for us. There just must be. We were wrong about the fat, but we’re right about it being meat.
A really brilliant PhD friend wrote the following referring to the study:
I think it (referring ot the paper) has some interesting things however irrelevant for human health. It is a kind of microcosm of what’s wrong with medical science, exaggerating minor points and using statistics to hide rather than explain the truth. For those who don’t have time, I provide a synopsis of the introduction:
…is linked to…presumably…prompting the suggestion …the suspicion…may not be sufficiently high enough …has been linked … raise the possibility …may … have not been fully clarified … has not been evaluated.
I think quite soon the registered dieticians of the world will suddenly snap out of their curse of the mummy approach to nutrition, unravel their blinding bandages and start denouncing vegan diets while eating a leg of lamb with their bare hands. I just can’t wait. But it’s not for today.
In the mean time, smarty pants people like Chris Kresser and Chris Masterjohn have written about this study with much greater expertise and brain power than I ever could, so, I won’t even try to explain it better. In his blog post, which you must read if you want to be able to explain the thing to your own mother in-law, Masterjohn exposes the following confounder (of which there are dozens):
Adjusting for body weight, this is like a human eating a thousand steaks per day. This is beyond the capacity of even the most die-hard meat-lovers.
Well, maybe not Jimmy Moore (Oh, c’mon, I KID Jimmy). This of course got me to thinking…why didn’t the researchers come to the same conclusions as Masterjohn (and Kresser) and state the same points in their discussion? Why didn’t they express the same caveats and confounders? Why instead did they come to the conclusion that meat promotes heart disease? I think I know why.
On the last page of the paper, the researchers state:
Our studies reveal a new pathway potentially linking dietary red meat ingestion with atherosclerosis pathogenesis. The role of gut microbiota in this pathway suggests new potential therapeutic targets for preventing CVD.
Ahhhhhhhhhh. Medicines. New drugs. Big profits. Since the good Lord knows that people will keep eating red meat regardless of our brilliant findings, let’s just kill the gut bacteria with a new, powerful antibiotic and viola! Heart disease will vanish. Good thinking. Like a famous boxing trainer once said “Kill the body and the head will die.”
Titles of papers like this one:
Intestinal microbiota metabolism of l-carnitine, a nutrient in red meat, promotes atherosclerosis
are the very fodder that the press love to pretzel into statments like:
EXTRA! EXTRA! Read all about it! Another Deadly Nail in the Coffin for Red Meat – and You! Eat Meat and Your Heart Will Die.
Both of the lead researchers have ties to big pharma by the by. How surprising.
And if after reading this blog post and all the links therein you still think eating meat will kill you, you can always enjoy Denise Minger’s mind on the matter of meat and heart health.
So there you have it. Now I have to go write a response to my doting mother in-law’s forthcoming email – I know it’s on the way. How shall I start it…
Dear Mom – thanks for the sweater. Of course it fits! Now, as for meat…
ADDITION: I neglected to add the Science Friday radio piece on this subject. After reading this and Chris Masterjohn’s blog, listen to the show. You’ll hear how biased – or clueless – the scientist being interviewed truly is.