Find Information About:

Drugs & Supplements

Get information and reviews on prescription drugs, over-the-counter medications, vitamins, and supplements. Search by name or medical condition.

Pill Identifier

Pill Identifier

Having trouble identifying your pills?

Enter the shape, color, or imprint of your prescription or OTC drug. Our pill identification tool will display pictures that you can compare to your pill.

Get Started
My Medicine

My Medicine

Save your medicine, check interactions, sign up for FDA alerts, create family profiles and more.

Get Started

WebMD Health Experts and Community

Talk to health experts and other people like you in WebMD's Communities. It's a safe forum where you can create or participate in support groups and discussions about health topics that interest you.

  • Second Opinion

    Second Opinion

    Read expert perspectives on popular health topics.

  • Community


    Connect with people like you, and get expert guidance on living a healthy life.

Got a health question? Get answers provided by leading organizations, doctors, and experts.

Get Answers

Sign up to receive WebMD's award-winning content delivered to your inbox.

Sign Up

Diabetes Health Center

Font Size

Recipe for Diabetes: Too Much Protein, Fat

Protein Worsens Insulin Resistance From High-Fat Diet
WebMD Health News

April 7, 2009 -- Too much "good" protein makes bad fats worse, new research suggests.

A high-fat diet may lead to insulin resistance, a major step on the path to type 2 diabetes. But cutting back on fat may not help those who continue to eat too much protein, find Christopher Newgard, PhD, director of the Sarah Stedman Nutrition and Metabolism Center at Duke University, and colleagues.

"There's not only fat in that hamburger but plenty of protein," Newgard tells WebMD. "We are overconsuming calories composed of all the different macronutrients, and together they have harmful effects."

When they began their studies, Newgard and colleagues weren't trying to give protein a bad name. They were just trying to find out how the metabolism of obese people differs from that of lean people.

To do this, they collected vast amounts of information -- including high-tech lab tests on blood and urine samples -- from 74 healthy obese people and 67 healthy lean people.

Unexpectedly, obese people had a distinct metabolic "signature" related to a particular subtype of amino acids called BCAA (branched-chain amino acids). About 20% of the protein in the typical American diet is made up of BCAAs.

Lean people's bodies tend to make new proteins out of BCAAs. In obese people, Newgard and colleagues suggest, this process gets overloaded. Instead of making new protein, the BCAAs are diverted into a deviant pathway that leads to insulin resistance.

Can too much protein really be bad? Yes -- at least in lab rats. Newgard's team fed rats all the high-fat food they wanted. Two other groups of rats got less food: either standard chow or chow enriched with fats and BCAAs.

The rats on the BCAA/fat diet didn't eat as much food or gain as much weight as the rats on the high-fat diet -- but they became just as insulin resistant.

"Under circumstances of overconsumption, not only does excess fat and carbohydrate have injurious effects, but also the protein component of the diet can lead to some of the co-morbidities of obesity," Newgard says.

Human studies will be needed to confirm the rat findings. But Ronald B. Goldberg, MD, director of the lipid disorders clinic at the University of Miami, says the findings could have major implications.

"What they show is that the combination of high fat and protein might be what's important in developing insulin resistance," Goldberg tells WebMD. "The truth is that in Western diets we do eat a high-protein, high-fat diet. The stress previously has not been on the high-protein component."

The Newgard study appears in the April 8 issue of the journal Cell Metabolism.

Today on WebMD

Diabetic tools
Symptoms, diagnosis, treatment, and more.
woman flexing muscles
10 strength training exercises.
Blood sugar test
12 practical tips.
Tom Hanks
Stars living with type 1 or type 2.
kenneth fujioka, md
Can Vinegar Treat Diabetes
Middle aged person
jennie brand miller

Prediabetes How to Prevent Type 2 Diabetes
type 2 diabetes
food fitness planner