High Fat Diet causes insulin resistance

[Paul McGlothin]

When CR folk plan the macronutrient ratios in their diet, they may want to take this study ( and others like it) into account:

 

High-fat diets cause insulin resistance despite an increase in muscle mitochondria.

 

Proc Natl Acad Sci U S A. 2008 Jun 3;105(22):7815-20.

 

 

Hancock CR, Han DH, Chen M, Terada S, Yasuda T, Wright DC, Holloszy JO.

 

Source

Division of Geriatrics and Nutritional Sciences, Department of Medicine, Washington University School of Medicine, St. Louis, MO 63110.

 

 

Abstract

It has been hypothesized that insulin resistance is mediated by a deficiency of mitochondria in skeletal muscle. In keeping with this hypothesis, high-fat diets that cause insulin resistance have been reported to result in a decrease in muscle mitochondria. In contrast, we found that feeding rats high-fat diets that cause muscle insulin resistance results in a concomitant gradual increase in muscle mitochondria. This adaptation appears to be mediated by activation of peroxisome proliferator-activated receptor (PPAR)delta by fatty acids, which results in a gradual, posttranscriptionally regulated increase in PPAR gamma coactivator 1alpha (PGC-1alpha) protein expression. Similarly, overexpression of PPARdelta results in a large increase in PGC-1alpha protein in the absence of any increase in PGC-1alpha mRNA. We interpret our findings as evidence that raising free fatty acids results in an increase in mitochondria by activating PPARdelta, which mediates a posttranscriptional increase in PGC-1alpha. Our findings argue against the concept that insulin resistance is mediated by a deficiency of muscle mitochondria.

 

PMID:18509063

 

 

The full paper is attached.

 

I noticed that other questions here regard what macronutrient ratios are best for a CR lifestyle. I hope this study is helpful in that regard.

 

 

Paul

High fat diets cause insulin resistance.pdf

[Littlefish]

What does this mean? How can I make use of this information? What is your conclusion to an interested lay person?

[Paul McGlothin]

What does this mean? How can I make use of this information? What is your conclusion to an interested lay person?

 

It means be careful about including too much fat in your diet, even if it's heart-healthy. If you can't control your glucose after eating good, low GI carbohydrates, fat might be the culprit.

 

Paul

[Guest Mike C.]

It means be careful about including too much fat in your diet, even if it's heart-healthy. If you can't control your glucose after eating good, low GI carbohydrates, fat might be the culprit.

 

Paul

 

Thanks for that information Paul,

One thing to keep in mind with studies like this is the simple fact that humans vary in their responses. I find that up to 35% healthy fat diet dramatically lowers my triglycerides by a factor of three and raises my HDL from 50ish to 70 ish comprared to a very low fat diet of 12%. I also find that my glucose post meal is under better control with 35% fat vs. 12% or very low fat. Testing is the only way you will really know how you respond.

 

Mike C.