Saturday, December 6, 2008

Peripheral vs. Ectopic Fat

I went to an interesting presentation the other day by Dr. George Ioannou of the University of Washington, on obesity and liver disease. He made an interesting distinction between the health effects of two types of body fat. The first is called subcutaneous fat (or peripheral fat). It accumulates right under the skin and is evenly distributed over the body's surface area, including extremities. The second is called ectopic fat. Ectopic means "not where it's supposed to be". It accumulates in the abdominal region (beer belly), the liver, muscle tissue including the heart, the pancreas, and perhaps in lipid-rich deposits in the arteries. Subcutaneous fat can be measured by taking skinfold thickness in different places on the body, or sometimes by measuring arm or leg circumference. Ectopic fat can be measured by taking waist circumference.

It's an absolutely critical distinction, because ectopic fat associates with poor health outcomes while subcutaneous fat does not. In
this recent study, waist circumference was associated with increased risk of death while arm and leg circumference were associated with a reduced risk of death. I think the limb circumference association in this particular study is probably confounded by muscle mass, but other studies have also shown a strong, consistent association between ectopic fat and risk of death, but not subcutaneous fat. The same goes for dementia and a number of other diseases. I think it's more than an epidemiological asssociation. Surgically removing the abdominal fat from mice prevents insulin resistance and prolongs their lifespan.

People with excess visceral fat are also
much more likely to have fatty liver and cirrhosis. It makes sense if you think of them both as manifestations of ectopic fat. There's a spectrum of disorders that goes along with excess visceral fat and fatty liver: it's called the metabolic syndrome, and it affects a quarter of Americans (NHANES III). We already have a pretty good idea of what causes fatty liver, at least in lab animals: industrial vegetable oils and sugar. What's the most widely used animal model of metabolic syndrome? The sugar-fed rat. What are two of the main foods whose consumption has increased in recent decades? Vegetable oil and sugar. Hmm... Fatty liver is capable of causing insulin resistance and diabetes, according to a transgenic mouse that expresses a hepatitis C protein in its liver.

You want to keep your liver happy. All those blood tests they do in the doctor's office to see if you're healthy-- cholesterol levels, triglycerides, insulin, glucose--
reflect liver function to varying degrees.

Abdominal fat is a sign of ectopic fat distribution throughout the body, and its associated metabolic consequences. I think we know it's unhealthy on a subconscious level, because belly fat is not attractive whereas nicely distributed subcutaneous fat can be. If you have excess visceral fat, take it as a sign that your body does not like your current lifestyle. It might be time to think about changing your diet and exercise regime.
Here are some ideas.

17 comments:

Ed said...

Stephen,

I'm wondering if the "sugar" part of the issue could be further narrowed, to "fructose."

As you have mentioned before, many indigenous cultures mash, ferment, and otherwise pre-digest their foods to make them more nutritious and easier to absorb. I must assume that some of this process takes long-chain starches down to short-chain disaccharides and monosaccharides. But they would be dextrose (glucose) based, with no fructose component.

It makes me wonder if you fed a rat an otherwise "healthy" diet (eg no n-6 fats), and supplemented with moderate amounts of dextrose, if they would accumulate ectopic fat.

Part of my specific curiosity here is due to reading about weightlifters diets, for weight gain specifically. You can't add muscle mass without the insulin response. Somehow in the weightlifting lore, they have figured that the best way to do that is with dextrose + protein supplements. Search for dextrose and you find it marketed at bodybuilders. I wonder if that causes ectopic fat accumulation.

eg

http://www.mens-total-fitness.com/window-of-opportunity.html

I wonder if a non-hyperinsulinemic insulin response causes excess ectopic fat. Or if that just causes peripheral fat. I wonder it those aren't mutually exclusive, and there is some contribution to both.

Lots of things to wonder. Dividing up fructose from glucose processing really changes my thinking about how the body works. I used to thing sucrose was equivalent to starches, just faster processing. Now I realize that the fructose element makes it totally unlike other digested starches. But dextrose is the end state of starches, so perhaps there is still some truth to the original concept.

I know Art de Vany would sooner die than contemplate the frankenstein shake described in the link above... but his isn't the only way to look at the world :-)

rnikoley said...

Stephan:

I have a relative who is / was pretty severely obese (5'5, around 300#), but has been following my blog, low-carbing / Paleoing for some months, and has dropped about 60# (yea!). She is also diagnosed type 2, but I believe the insulin treatment is oral at this stage, and I' not sure whether she has decreased it. I have a few questions out to her.

At any rate, she has elevated BG when getting up in the morning. Given the low-carbing and success at weight loss, I was wondering if the high a.m. BG is more likely explained by continued insulin resistance, correction of a fatty liver, gluconeogennesis (being 60# lighter, she probably doesn't need as much lean mass as she has), or something else entirely?

Your thoughts, or anyone else?

Dr. B G said...

Richard,
I like you have the right thoughts! R U sure ur not a secret biochem major?

Her liver may be dumping BG out in the morning as a result of mildly low glucoses in the middle of the night ('dawn phenomenon'). Low BG can trigger an adrenaline related flight-fright-fight response. Also naturally in the AM our cortisol (and adrenaline) has mild peaks prior to waking.

Remedies:
--protein snack prior to bed (+/- low carb snack like non-starchy veggies or few bites of sweet potato)
--avoid excessive carbs and fats prior to bed
--set alarm clock and check nocturnal 2AM BG -- if low < 80 than consider discussion with MD to reduce some of the oral drugs (esp sulfonylureas like glipizide or glyburide)

Long term remedy: make sure vitamin D and fish oil and other macro- and micronutrient deficiences are corrected (magnesium, chromium, zinc, etc)

Hope that helps! G

daiikkon said...

Hey Stephen

Great information you have here. I love that there are still people with common sense about diet.

I was vegan for about 5 years. I believe I have developed malnutrition. My eyes most notably burn all the time and hurt. The lids are very red and are always losing lashes. My teeth have also developed some decay and my hair is quite brittle. Just recently I have been adding calf's liver, raw cream, eggs, & other meats to my diet. I am starting to feel better but still weak. I am only 27 so I doubt I should be feeling this way now.

Do you have any suggestions to really jump start my system again?

Also would raw cream have the same vitamin properties as butter?

Thank You

Robert Andrew Brown said...

Daiikon

It sounds to me as if you should make sure you have been to see a doctor and nutritionist as a starting point.

I cannot give advice, but would observe that vegetarians often have diets that are high in Omega 6 and lacking in Omega 3.

Fish and shell fish has to be the first choice as it provides a package of omegas minerals iodine etc. Cod liver oil is a good source of Omega 3s and vitamin A and D (but see Stephan's blogs on types of cod liver oil).

Dry hair eye problems and gum problems all have been linked to Omega 3 6 imbalance, so improving your fats intake profile may help.

But again make sure you seek professional advice as to your health.


Robert Brown

Author: Omega Six The Devils Fat

www.omegasixthedevilsfat

Stephan said...

Ed,

I do think fructose is a big part of the equation, maybe most of it. I suspect that the sweet taste itself is also part of it though. Neurologically, a concentrated sweet flavor has drug-like effects on the brain, whether it comes from fructose, glucose or a non-caloric sweetener. Rodents (and I believe humans) will eat concentrated sugar to excess, preferring it even to drugs like cocaine in some cases. I can speak for myself that fruit doesn't do that to me, whereas sweet chocolate or cookies will send me on a binge.

I don't have an answer to your question about insulin spikes/hyperinsulinemia and fat accumulation, but I wish I did because it's interesting. I do know that hyperinsulinemia tracks with ectopic fat, so there seems to be some relationship between the two.

Richard,

Elevated fasting glucose could mean she's still insulin resistant in her liver. If the liver isn't getting the signal that there's already enough glucose in the blood, it will pump it out. That's my guess anyway. What G said makes sense too and is related. Balancing omegas and getting rid of sugar may help that. Both may take a while to work, especially the omegas. There's always paleo, if you can get her to go that far. Nice job helping her get healthy!

Daiikon,

Well I'm glad you've realized it wasn't agreeing with you! I agree with what Robert said about balancing omegas. That could be a critical element.

I am going to guess that what your body is lacking is animal nutrients. My top recommendations are to take cod liver oil and eat generous amounts of grass-pastured butter, pastured eggs, assorted organs and shellfish. You may also be lacking in minerals, so make sure to treat your grains or legumes properly by soaking, sprouting or fermenting them. Keep us updated on your progress! Sally Fallon has a book called "Nourishing Traditions" that's a good place to start if you need help with the practical side of it.

Stephan said...

Oh and make it high-vitamin cod liver oil, not the wimpy stuff they sell in the grocery store. The Weston Price foundation has trustworthy brand recommendations on their site.

theoddbod said...

I was just wondering if during the talk there was any mention of any adipokines (leptin, adiponectin, resistin, etc...) and their influence on NAFLD, insulin resistance and all that other good stuff associated with metabolic syndrome. I say this because pretty much no talk about obesity and metabolic syndrome is complete without mentioning them,since we all now know that fat is not just a storage depot for energy but a full blown endocrine organ that has a profound influence on our entire body from appetite to signal transduction in cells.

theoddbod said...

and I also find it super-interesting! great post by the way.

daiikkon said...

Thanks for the advice guys. I have been sprouting brown rice & rye. Himalayan pink salt seems to be helping me quite a bit.

Is raw cream as effective as butter? I can't find raw butter right now but I have been eating lots of raw cream.

Robert M. said...

It's probably worthwhile to separate interstitial muscle fat from visceral fat around the smooth muscle in your organs. Visceral fat is definitely dangerous as hell, interstitial probably not. IIRC, interstitial and subcutaneous fat share the same composition. In fact there's plenty of evidence that fat stores extend life when the G-I system begins to fail as a person gets into their 80s.

On the dextrose/glucose building muscle: it doesn't, as far as I know. It does fill up the interstitial fat sites in the muscle, which increases bulk and strength (by providing leverage for the muscle fibres). The muscles are perfused with blood post-workout, so they simply see a higher flow of sugar than the rest of the body in that situation. It will hamper your power-to-weight ratio, so it really depends on which sports you play on whether you want to glucose load afterward. Hockey/football players, yes, cyclists, not so much.

Post-workout glucose shouldn't in general be going to the organs. That comes more from fructose/alcohol and or total body saturation with glucose. The heart is the unknown factor. Most people should just have a protein snack after exercise and they should be fine.

gunther gatherer said...

Hi Stephen and thanks for this. Very informative.

I'm writing from Germany, where raw dairy is not sold in stores. Do you have an opinion one way or the other on pasteurisation? I've heard various views on the pros and cons, but can't get a clear picture of how this process could hurt digestion/mineral absorption.

(I apologize for the hijack, if it's too big an explanation, may I suggest a post on it some day?)

Stephan said...

Theoddbod,

I don't recall him mentioning those, although it was a pretty clinically oriented talk. I agree that the endocrine function of fat is important. That may be the reason why abdominal fat correlates with insulin resistance.

Daiikkon,

Raw cream will be a good addition to your diet. The reason I like butter so much is it's a concentrated source of vitamins and it doesn't contain much lactose or casein, so it isn't usually problematic for people with milk intolerance. But cream works well too as long as you tolerate dairy well.

Robert,

Thanks for pointing that out.

Gunther,

I do think raw is better. My #1 reason for saying that is I know several people who are supposedly milk intolerant but who tolerate raw milk just fine. It may have something to do with the fact that pasteurization destroys the enzymes such as lactase.

Ed said...

Robert M: the bodybuilders don't say dextrose directly builds muscle. Rather, they say insulin is required to drive protein into muscle. I find it interesting that they figured to use dextrose instead of sucrose to trigger the insulin response. Form competitors don't want love handles. Does dextrose provide biochemical hormonal benefits without any or just not much ectopic fat? Or just less ectopic fat than you would get from sucrose or fructose?

Rob said...

Hey Stephen, this is a bit off topic, but since insulin has an affect on nearly all body processes.. here is a great article about insulin and it's metabolic effects transcribed from a talk of Dr. Ron Rosedale. I'm not sure if you have read it before, but here is a link:
http://articles.mercola.com/sites/articles/archive/2001/07/14/insulin-part-one.aspx

One thing I find interesting is that he recommends lots of vitamin E with cod liver oil because he claims the PUFA's will become oxidized without it. I know the vitamins A and D work to prevent this oxidation, but his vitamin E bias is getting me curious, and I know you said you were going to look into it in the future.

Stephan said...

Rob,

I think some of it can oxidize. Most brands add vitamin E or some other antioxidant to prevent this. Still, it's probably best not to take a lot if it.

Interestingly, Green Pastures fermented CLO has fewer lipid peroxides than regular CLO, even without antioxidants. I guess the little beasts secrete antioxidants into the oil.

Being Healthier said...

love your site. I have a BS in Neuroscience and an MS in Nutrition ... I am considering what to get the PhD in because nutrition is so much " dietetics" now and I'm interested in the neuro/physio/metabolic... Suggestions?

I'm teaching a grad course now in obesity and weight management- that's how I found your blog somehow in searching for lecture resources on ectopic and peripheral fat.

-Laural @ Being Healthier
www.beinghealthier.com