Wednesday, March 17, 2010

Paradox: Obesity and heart failure

Just taking a break from the busy stuff going on away from the blog. This paper deserves a brief comment. Here is a mainstream discussion, thanks Elizabeth. [And here is the text for when the blog link goes down].

To begin:

"Being skinny confers no advantage when it comes to the risk of dying suddenly from cardiac causes"

That lead statement about being skinny is somewhat misleading. A 99% increase in risk is not quite neutral....

So how does a lipophile see this paradox?

Well, the first thing is that the population is pre-selected. They have (a) had a heart attack and (b) have cardiac muscle wastage.

It's a little pointless going through the detail of the studies linking hyperglycaemia to heart disease when Jenny Ruhl has very neatly collated the studies that matter. I have mentioned the role of hyperglycaemia in cardiac muscle apoptosis before. Ischaemia and apoptosis is a great recipe for heart failure.


So we can reasonably describe this population as a set of people who have been routinely achieving post prandial blood glucose levels in excess of 8.0mmol/l, ie about 140mg/dl, almost certainly for years.

How they have achieved this seems unimportant, what matters to me is that by definition this is a group of recurrently hyperglycaemic people. Their LDL cholesterol level is of no interest and, thankfully, does not get mentioned here.

Why do the skinny people do so badly?

These people are skinny. They don't eat huge amounts of calories, but what they do eat spikes their blood sugar. They may well not be hyperinsulinaemic. After all, they are not squirreling away fat and they are allowing their blood sugar to rise... Those suggest, if anything, a blunted insulin response. Is someone with a BMI of 21, who has just had a heart attack, going to set out to lose a serious amount of weight? No, I doubt it. Cutting the fat would probably be the standard advice, obviously cutting saturated fat specifically. But backing off on fat (that scary stuff which Ancel Keys told us causes heart attacks, and cardiologists still believe him!) will invariably lead to increased carbohydrate intake. We know these people already develop post prandial hyperglycaemia. Low fat means more hyperglycaemia. Hyperglycaemia = death.

What about the healthier fatties?

Obviously these people are recurrently hyperglycaemic too, again because they are in the same cardiovascular situation as the skinnies. But they must have been eating a bit more of everything in the past than the thin people. They have to have eaten more to (a) eat enough calories to move themselves around, (b) eat enough calories to provide enough for their basal metabolic rate and (c) eat enough fat to go in to storage in their adipocytes.

However, they do have considerable scope for weight loss and ANY reduction in calorie intake is likely to reduce carbohydrate calories somewhat, as well as fat calories. The two tend to go together. Any decrease in carbohydrate calories will reduce hyperglycaemia in a person who is proven to develop post prandial hyperglycaemia.

Even cutting fat can be good. Less omega 6 PUFA and less trans fats from the diet, both of which, during weight loss, get replaced by an excellent mix of saturated fat with some mono unsaturated fat from butt fat. Butt fat, once again, is an excellent and healthy source of calories.

I have no idea whether surviving a heart attack and having a pacemaker implanted in your chest might make you think about losing a little weight if you are officially obese. Perhaps it concentrates the mind a little. Or maybe overhearing what the doctor's skinny receptionist called you when she thought you were out of earshot might help!

Obesity should become protective when someone starts to use their stored fat, because human adipose tissue is a health resource which can usefully replace anything with a heart-healthy logo on its plastic wrapping. It doesn't spike glucose! The more weight you have to start with, the longer it takes before the corrosive effect of a low fat diet kicks in. This kicks in when you stop losing weight!

If someone is losing weight on a low fat diet there will obviously come a time when weight loss stops and, at that time, they then simply join the ranks of the initially skinny low-fat eaters but, of course, a fair few of those will be dead by then....

Leaves some space in the queue I guess.

Peter

13 comments:

Robert McLeod said...

I've always been under the impression that overweight elderly people live longer because when their digestive system starts to fail they have greater reserves, both fat and muscle, to draw down before they kick the bucket. Same mechanism I guess.

Anonymous said...

So lose weight or start to eat some animal fat.

I suppose if the obese are more likely to cut calories drastically ( who will tell the skinnies to cut calories?, it will all be canola oil and oatmeal for them), they are more likely to throw the switch into pretty good ketosis as well.

Shunting cardiomyocte metabolism away from broken glucose metabolism to fatty acids and ketones would definitely help heart failure. The skinnies have no fatty acids to do this with, unless they go to OD or PaNu type diet right off..

arnoud said...

The skinnies are very good at following their doctor's orders: oatmeal with some fruit for breakfast, whole wheat sandwiches with lean meat for lunch, and some lean meat with veggies and maybe pasta for dinner. Snacks: whole wheat crackers are OK, as long as you stay skinny.

Sadly that was the advise my father followed after a mild heart attach. It gave him three years until his fatal 'sudden' heart arrest. He even gave up all cheese. A handful of (wall)nuts was the only healthy fat he was told he could enjoy.

Surefire strategy to keep the medical 'assembly lines' through the cardiac centers running at full capacity.

blogblog said...

Both of my parents were almost certainly killed by well meaning health professionals. My parents were slightly overweight. They were subjected to decades of medically supervised very low fat diets. Neither parent lost any weight but both died in their 60s from heart attacks. My mother's grossly obese sister is 80 and still going well.

Peter said...

Rob

Ah, could be, do you have a ref on gut dysfunction? There's lots of anecdote to support this. We know HbA1c rises with age. Mechanism: advancing gut damage, endotoxin translocation, hepatic inflammation, impaired glucose tolerance, hyperglycaemia? We're back to jam (jelly??) with peanut butter over margarine on bread...

Kurt, yes. But the other complication is that mitochondria eventually break or give up in diabetes/hyperglycaemia. Then fatty acids become unavailable and ketones are left as the ultimate mitochondrial fuel... Seems like mitochondria keep ketone oxidation for when all else fails.

arnould, yes, but the flip side is that people who follow doctors orders always do better than those who don't, even if they get the placebo! Might be how come they make it to being older before their first heart attack. But ultimately following doctors orders can't beat the hyperglycaemia those orders produce.

Sadly I think the "assembly lines" are largely people doing the best they can. The paradigm setters are the main crooks. Work on the coal face is just making the best living you can under the conditions you work in... We all do that.

blogblog, of course I have no idea if the heavy people really lost weight after a heart attack in this study. They may simply be getting adequate micro nutrient nutrition at the cost of hyper nutrition or there is something in the fat we eat which is essential for health... Of course someone who is obese and still gaining weight is quite possibly normoglycaemic if they make enough insulin to achieve this, and coincidentally store fat... It's when you run out of space in the adipocytes that the problems begin...

Peter

Anonymous said...

I guess I should have said "away from fatty acids to fatty acid derived ketones made by the liver"'.. more accurate as cardiomyocytes already prefer fatty acids.

LynneC said...

"Obese patients are hard on their bodies; many don't eat right, don't exercise, and many smoke," explained Eric Hansen, co-lead author and also a second year medical student at the University of Rochester. "If their bodies are surviving this bad treatment then perhaps they are better equipped, from a genetic standpoint, to live with heart failure."

This is my faviorite comment from the study. Future MD, no less.
Peter, I'll stick with your hypothesis...

Unknown said...

Peter,

I'm sure you've answered this before, but 1) Will a higher fat, low-carb diet heal "advancing gut damage, endotoxin translocation, hepatic inflammation, impaired glucose tolerance, hyperglycaemia"? I am suffering from all of these, but whenever I eat a high fat meal with little or no carbs, I feel like the meal is not complete without something sweet! 2) What would be the limit on carbs to heal those impairments? 3) Do you have any posts on salicylate intolerance?

Thank you!

Ceuta

Ned Kock said...

Dr. Davis mentioned in a recent post the connection between elevated Lp(a) and some demographic characteristics. Those were supposed to be inherited, as was the tendency to have elevated Lp(a).

One of those demog.'s was being thin. Some of the others were being smart, and having above average aerobic performance! I couldn't find the link to the article though. Have you seen it?

MontyApollo said...

Hi Ned,

Peter commented in one of the threads at Dr. Davis's site, and he did a blog post about it here. Here are the links:

http://high-fat-nutrition.blogspot.com/2010/02/saturated-fat-and-sdldl.html

http://heartscanblog.blogspot.com/2010/02/genetic-vs-lifestyle-small-ldl.html

Ned Kock said...

Actually, the post, which I have just found, is this:

http://heartscanblog.blogspot.com/2010/02/prototypical-lipoproteina.html

Stacy said...

Something in this article clicked with me. It's brilliant! When your fat and losing weight your protected by the fat in your body, when your skinny there isn't much fat for your body to consume and so you need the dietary fat to be healthy. Is that it?

Mary Joy said...

I have skinny friend who suffered form heart attack last two weeks ago. He's of old age, hypertensive and diabetic as well. After staying one week in the intensive care unit and one week at the recovery room,Thank God, he's now fine yet very skinny.