Sunday, 28 February 2010

We are not all the same.

Cont'd from Everyone is Different.

Lyle (McDonald) brought the following study to my attention to illustrate that "We are not all the same":- Some Metabolic Changes Induced by Low Carbohydrate Diets. On a very-low-carb diet, one subject’s total cholesterol rose to 12.9mmol/L (500mg/dL in US units). The others didn't.
See also LDL cholesterol goes sky high on fatty diet.

I posted the study in various blogs to make the above point. Here are some of the replies I got:-
"Lyle? Lyle McDonald? Is that where you got that study, Nigel?" and... "I’m usually a pretty polite guy, Nigel. But based on this quote from the beginning of the study you mentioned, the people who wrote this study were a bunch of f**kwads, and really don’t deserve our attention. It’s a hatchet job."
"That was a weird study (1967) what I could make of it." and... "The men did all the stages but the women only did 3 stages of the diet."
"The fats were mostly omega-6 PUFA 13-35 grams worth..."
"The report you cite is so old and out of date that it makes me cry..."

My point was well & truly missed. I got the distinct impression that people thought I was criticising very-low-carb, high-fat diets. I wasn't. The simple fact is that there is no "One True Diet" that suits absolutely everybody. In the olden days everywhere & in poor countries nowadays, people that ate/eat the wrong diet for their body died/die young. Nowadays in rich countries, they get put on drugs e.g. oral hypoglycaemics (to lower blood glucose) & hypolipidaemics (to lower blood cholesterol/triglycerides).

Please note that omega-6 PUFAs tend to lower serum cholesterol rather than raise it, as per Figure. 1 below from Individual fatty acid effects on plasma lipids and lipoproteins: human studies.

However, don't rush off and eat shed-loads of omega-6 PUFA (e.g. corn oil) in the mistaken belief that it will make you live any longer.

Cont'd on Everyone is Different, Part 2.


dextery said...

Stephan has two recent postings about corn oil:

Corn Oil and Cancer: Reality Strikes Again Feb 26th posting

Dissolve Away those Pesky Bones with Corn Oil Feb 16th posting

Nigel Kinbrum said...

Hi Dexter.

I left a comment (10th one down) with a link to the Lancet article in "Corn Oil and Cancer: Reality Strikes Again"


Jake said...

Omega 6 fats oxidize LDL and oxidized LDL is the main driver of plaque growth. The liver recognizes oxidized LDL as a poison and thus try to remove it from the blood stream. That poison removal process reduces LDL levels.

Taking Omega 6 fats to reduce LDL is like taking arsenic to cure a cold.

Nigel Kinbrum said...

Hi Jake.

Sadly, reducing LDL (by any means) is what the public are advised to do. I wonder how many more years it'll be before doctors look at cholesterol particle "quality" rather than quantity? I gather that an ApoA:ApoB ratio test is more relevant to heart health than LDL, HDL & TG, but it's not routinely done here (I got it done once, by request).

Cheers, Nige.

Preston said...

I've found a VERY hostile and irrational reaction from paleo-cult type people on their blogs if you bring up a reasonable question or some evidence that may poke holes in some of their beliefs. It turns out
people like Alan and Lyle are right about the cult mentality. It's much easier to be open to what the science does and does NOT say when you are not married to any ideology.

Nigel Kinbrum said...

Hi Preston.

Although I'm pro low-carb diets (as is Anthony Colpo), we're both as popular as a fart in a space-suit for stating that Taubes has got his biochemistry wrong, dietary fat can be stored as bodyfat and calories do count. Hey-ho!

Cheers, Nige.

Anonymous said...

Jenny Ruhl's post on low carb diets and cholesterol might be of interest.


If the folks who write the low carb diet books would point out that the cholesterol numbers could go up during the first phase of a low carb diet, and will then go down, after a few months, this would save a lot of the worry.

If I run across Peter Dobromylskyj's post on this, at his blog, Hyperlipid, I will post the link here.

Thanks very much for your blog. I'm enjoying reading it.

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