Comments on: Observational studies

By: John

John — Fri, 21 Sep 2007 22:58:40 +0000

I�ll have to look up the real SJ quote in my small library of SJ�s writings.

No need. Here it is:

“Sir, I have found you an explanation, but I am not obliged to find you an understanding.”

I think my own paraphrase is a bit of an improvement, realizing, though, that I too stand on the shoulders of giants.

John

Hey John–

I agree – I think your modernization is an improvement.

Cheers–

MRE

By: thomas

thomas — Fri, 21 Sep 2007 19:00:14 +0000

Dr. Mike,

Another excellent, penetrating post. Thanks to your blog, I now know how to look at these types of studies and pick apart what’s wrong with them. You’ve really opened my eyes to a great many things.

The other day I came across an assessment of another observational study, evidently published recently in the journal “Obesity”. Said study looked at the correlation between alcohol consumption and “beer bellies”. Part of the findings indicate “there was a very �robust� association between alcohol intake, waist circumference and waist to hip ratio. They pointed out that a high alcohol intake, especially hard liquor, was closely associated with abdominal body fat, not just overall body mass.” Can you say “duh”?

But one paragraph caught my attention: “Another thing that confounds the reports on whether alcohol contributes to weight gain is the fact that the game changes in heavy drinkers. We know that alcohol contains 7.1 calories per gram and these calories always count as part of the energy balance equation� or do they? With chronic excessive alcohol consumption, it�s possible that not all of these calories are available for energy. Due to changes in liver function and something called the microsomal ethanol oxidizing system (MEOS), alcoholism may be a real case of where some calories don�t count.”

Huh? I already knew that while drinking the body will burn the alcohol preferentially as fuel ((to purge the toxins?), while inhibiting fat oxidation (and this is indeed mentioned in this fellow’s assessment). But why would this “calories don’t count” only apply to heavy, chronic drinkers. Or is his science, uh… impaired? Just curious, cuz I enjoy lowcarb beer in moderation (occassionally somewhat more than moderation,lol). Do I not metabolize/process the alcohol in the same way as a heavy chronic drinker? Many thanks, and again, great job!

thomas

Hi Thomas–

Heavy drinkers have more liver enzymes and can metabolize alcohol faster than you, assuming you’re not a heavy drinker. But, with time, these heavy drinkers destroy their livers and reach the point where they can’t much metabolize alcohol at all. Manny of them continue to drink, however, and it kills them.

Best–

MRE

By: John Spaulding

John Spaulding — Fri, 21 Sep 2007 03:01:42 +0000

That�s perfect. Who said it?

It’s a paraphrase of a Samuel Johnson quote.

Another retort I like to pull out now an then: “Well, I’ll say this much for you – you sure don’t
embarrass easy.”

John

Thanks, John–

I’ll have to look up the real SJ quote in my small library of SJ’s writings.

Cheers–

MRE

By: John

John — Thu, 20 Sep 2007 20:53:34 +0000

“You can buy them the books and send them to school, but you can�t make them open their minds.”

My favorite quote, along those lines, is this:

“I have provided you an explanation. I am unable to furnish an understanding.”

- John

Hey John–

That’s perfect. Who said it?

Best–

MRE

By: Marilyn Leahy

Marilyn Leahy — Thu, 20 Sep 2007 17:49:26 +0000

I wonder. After reading Taubes brilliant article in the Times I checked out the debate on Charlie Rose on U-tube.Taubes was heckled badgered and scorned by the AHA dupe and Dean Ornish. Several times Ornish stated that he would be the first to change his mind when he was shown the evidence. Seems that Taubes is giving Ornish that chance at last. I am not holding my breath. But I am going to buy lots of copies of Ornish�s book for Christmas this year. Especially for all the dietitians I know.

I wish Taubes did have a biog so I could tell him thanks in person. As I again thank you for your courage and persistence in bucking the vested interests that are killing us and destroying one of the simple joys of life: eating good food.

Hi Marilyn–

Didn’t you mean that you were going to buy lots of copies of Taubes’ book for Christmas…? If so, sounds like a great gift, but don’t hold your breath that it will be read. Most people have their minds made up, and when confronted with such a book will make inane remarks along the lines of Oh, it’s just the same old discredited low-carb propaganda. You can buy them the books and send them to school, but you can’t make them open their minds.

I’ll pass along your thanks to Gary.

Cheers–

MRE

By: Jennifer

Jennifer — Thu, 20 Sep 2007 17:23:15 +0000

Thanks for the clarification–it was very helpful.

So I suppose the studies like this one:

http://content.onlinejacc.org/cgi/content/full/j.jacc.2006.04.080v1

…provide a good example of an over-reported observational study? The power of the study is very weak using only 14 subjects.

This site is a great resource for me, Dr. Mike. I’m glad you don’t mind my questions.

Hi Jennifer–

I wrote an entire post on this very study about a year ago. (Click here to read it.)

Best–

MRE

By: Travis T

Travis T — Thu, 20 Sep 2007 17:14:55 +0000

A different take on the global warming Vs pirates. I think the chart proves that it isn’t the loss of pirates that causes global warming but that global warming is deadly to pirates.

I wondered what happened to them all. The chart now makes it all clear.

Cheers–

MRE

By: simon fellows

simon fellows — Thu, 20 Sep 2007 17:01:19 +0000

Sir..is not also twoo that yr old Mucka Ricardo Veech says that ketones actually have anti-inflam properties ?

Thanks much as always yr enlightening blog

Yep, Veech has said same.

Cheers–

MRE

By: Esther

Esther — Thu, 20 Sep 2007 16:50:34 +0000

One of those pockets of good sense being in Santa Barbara, I’m sure.

Yes, I had a wonderful time! And you are right about California being beautiful. We drove down the PCH one day and stopped in at Geoffrey’s in Malibu for lunch. A lovely place and I highly recommend it if you and MD are ever in the area. The oceanside view from the dining area is spectacular.

There is probably a small pocket in Santa Barbara, though that pocket has migrated to Tahoe right now.

MD and I love Geoffrey’s and stop there just about every time we drive down to the LA area. It’s pricey but the setting is worth it. The food is pretty good, too.

Best–

MRE

By: Kathy

Kathy — Thu, 20 Sep 2007 16:18:09 +0000

Forgive me for posting again, but I’m in the midst of reading the entire article by Taubes and the following caught my eye:

Indeed, if you ask the more skeptical epidemiologists in the field what diet and lifestyle factors have been convincingly established as causes of common chronic diseases based on observational studies without clinical trials, you�ll get a very short list: smoking as a cause of lung cancer and cardiovascular disease, sun exposure for skin cancer, sexual activity to spread the papilloma virus that causes cervical cancer and perhaps alcohol for a few different cancers as well.

Again, it’s a bit off topic, but what do you think about his statement regarding sun exposure and skin cancer as a lifestyle factor that has been convincingly established as a cause of a chronic disease?

I’ve read your opinions on sun exposure (specifically in reference to sunscreens) and agree with them whole-heartedly. Perhaps the causal relationship between the sun and skin cancer isn’t quite so convincingly established? What about a possible relationship between sunSCREEN and skin cancer?

Also a bit curious about his reference to alcohol and cancers.

Thanks!

Hi Kathy–

He’s right in that sun exposure does cause a type of skin cancer that is fairly benign. And it can cause melanoma. But, strangely, it also protects against melanoma. Sun exposure is a two-edged sword in that it has both beneficial and detrimental effects. The task is to balance those so that you get the beneficial effects while minimizing the detrimental effects.

As to alcohol and cancers, there is no question that cirrhosis leads to liver cancer. And there is no question that overconsumption of alcohol leads to cirrhosis. So, alcohol is indeed a cause of much, but not all, liver cancer.

Best–

MRE