Study: Low-Carb Lowers, Low-Fat Diet Increases Inflammation, Saturated Fat In The Blood

Dr. Jeff Volek says controlling insulin is vital to blood lipids

A little over two years ago, I shared with you this study on the connection between metabolic syndrome and livin' la vida low-carb. The researchers were Dr. Jeff Volek from the University of Connecticut and Dr. Richard Feinman from SUNY Downstate Medical Center in Brooklyn, NY and they were absolutely fascinated by the rather obvious intertwining of a natural dietary approach like low-carb improving virtually every single area of metabolic syndrome (a precursor to diabetes, heart disease and stroke), including obesity, high triglycerides, low HDL "good" cholesterol, high blood sugar, hypertension and insulin resistance.

Now there is brand new research from these same two researchers with something quite startling regarding a comparison between a low-fat and a low-carb diet as it relates to inflammation and saturated fat in the bloodstream.

Lead researcher Dr. Jeff S. Volek, PhD, RD from the Department of Kinesiology at the University of Connecticut and his team of outstanding researchers (including Dr. Feinman, Dr. Stephen Phinney, and the soon-to-be Dr. Cassandra Forsythe, among others) tested the various components of metabolic syndrome comparing a carbohydrate-restricted diet with a low-fat diet in overweight men and women over a 12-week period. The study participants were split into one of two groups:

VLCKD (very low-carb ketogenic diet)--1504 calories
Fat/Protein/Carbohydrate ratio of 59/28/12

OR

LFD (low-fat diet)--1478 calories
Fat/Protein/Carbohydrate ration of 24/20/56

What did Dr. Volek and his team of researchers find?

Total saturated fatty acids in the blood actually DECREASED in the VLCKD group while the anti-inflammatory markers also "significantly decreased." Meanwhile, the LFD group, which consumed two-thirds less saturated fat than the VLCKD group, saw an INCREASE in total saturated fat in the bloodstream despite reducing fat intake.

This was totally unexpected as the conventional wisdom regarding saturated fat consumption is that it causes an increase in inflammation which leads to a worsening of the metabolic syndrome conditions and overall health. But that's not what happened.

"A very low carbohydrate diet resulted in profound alterations in fatty acid composition and reduced inflammation compared to a low fat diet," the researchers concluded.

This study was published in the November 29, 2007 issue of the scientific journal Lipids.

So what are we to make of this research in light of all we've ever been told about saturated fat? Doctors and nutritionists have long told their patients with metabolic syndrome symptoms to eat a low-fat diet and now science like this one is showing the shortsightedness of this unproven recommendation. Livin' la vida low-carb is making great strides behind-the-scenes because it is an excellent way to reduce triglycerides and other essential health markers related to inflammation.

Dr. Volek says this new study shows how a controlled-carbohydrate nutritional approach is "adding to the evolving picture of improvement in general health beyond simple weight loss in keeping blood glucose and insulin under control." And he believes this hyperinsulinemia is the root cause behind obesity, diabetes, and a whole host of other preventable diseases that all improve with the use of a low-carb diet.

Interestingly, the Volek study in Lipids is only a small portion of a much larger study currently under peer review. The full study shows even more improvements in blood lipids (cholesterol) with the stunning conclusion that "lowering total and saturated fat only had a small effect on circulating inflammatory markers whereas reducing carbohydrate led to considerably greater reductions in a number of pro-inflammatory" markers. Dr. Volek says this puts the onus of health risks back on the consumption of carbohydrates.

"These data implicate dietary carbohydrate rather than fat as a more significant nutritional factor contributing to inflammatory processes," he stated.

Meanwhile, Richard Feinman, PhD from the biochemistry department at SUNY Downstate Medical Center says this new research demonstrably shows why carb-restricted diets work so remarkably well.

"The real importance of diets that lower carbohydrate content is that they are grounded in mechanism: carbohydrates stimulate insulin secretion which biases fat metabolism towards storage rather than oxidation," Dr. Feinman explained. "The inflammation results open a new aspect of the problem. From a practical standpoint, continued demonstrations that carbohydrate restriction is more beneficial than low fat could be good news to those wishing to forestall or manage the diseases associated with metabolic syndrome."

Most damning against the low-fat diet hypothesis is the fact that although there was a three-fold higher saturated fat consumption by the VLCKD group, it was the LFD group that experienced higher saturated fat in the blood. Counterintuitive? You betcha!

"This clearly shows the limitations of the idea that ‘you are what you eat,'" Dr. Volek explained. "Metabolism plays a big role. You are what your body does with what you eat."

I like that--YOU ARE WHAT YOUR BODY DOES WITH WHAT YOU EAT! And that's why I'm livin' la vida low-carb because I have all the confidence in the world with what my body will do with the low-carb foods I consume. Controlled blood sugar and insulin levels, reduced triglycerides, lower blood pressure, increased HDL "good" cholesterol, and so much more than I could have ever expected from a high-fat, low-carb diet. It's hard not to appreciate something like this when your life has been so radically changed for the better. Now the research is showing us why.

Dr. Feinman succinctly repeated and summarized what I blogged about in this previous post regarding saturated fat consumption on the low-carb lifestyle in the following statement about this new study.

"I think even if you allow for tremendous error, it says that if carbs are low, saturated fat doesn't have much effect on the plasma composition," he remarked.

And that is why I don't worry about how much saturated fat I consume as long as my carbs are reduced. Now we have the science to back us up!

You can share your appreciation to Dr. Jeff Volek for his fantastic research by e-mailing him at jeff.volek@uconn.edu as well as Dr. Richard Feinman at rfeinman@downstate.edu.