diabetes supplement
Diabetes Diet

Comparing Low-Carb and Low-Glycemic

Nobody ever compared whether a low-carb or a low-glycemic diet works better to control our blood glucose levels. Until now.

Both diets improved A1C levels and helped participants in a 24-week study to lose weight. But the low-carb group did a lot better.

Five doctors at the Duke University Medical Center in Durham, North Carolina, just reported their results in the journal Nutrition & Metabolism. Led by Eric Westman, M.D., the study, “Effect of a low-carbohydrate, ketogenic diet versus a low-glycemic index diet on glycemic control in type 2 diabetes mellitus,” appeared on December 19.

The low-carb group followed a really low-carb diet — less than 20 grams of carbohydrate daily — but weren’t told to restrict their caloric intake. The low-glycemic group not only followed a low-GI diet but also reduced their caloric intake. Their diet gave them 500 calories per day less than they needed to maintain their weight.

Everyone in both groups had both type 2 diabetes and obesity. A total of 49 participants, who the researchers randomized to one group or the other, completed the study.

The researchers looked primarily at glycemic control as measured by A1C levels. Average A1C levels of the low-carb group went down 1.5 percent, for example from 8.5 to 7.0. Average A1C levels of the low-glycemic group went down too, but just 0.5 percent.

The low-carb group lost an average of 24 pounds. The low-glycemic group averaged a loss of 15 pounds.

HDL cholesterol — the so-called “good cholesterol” — also went up among the low-carb group, averaging an improvement of 5.6 mg/dl. But the low-glycemic group saw no change.

One more measure shows how powerful a low-carb diet can be: 95 percent of those in the low-carb group were able to reduce or eliminate their diabetes medication versus 62 percent for those in the low-glycemic group.

The researchers also provided some detail about the low-carb diet. Allowed foods were unlimited amounts of animal foods — including meat, poultry, fish, and shellfish — and eggs. Their limit for hard cheese was 4 ounces per day and for fresh cheese, like cottage or ricotta, 2 ounces per day. They could eat 2 cupfuls of salad vegetables and 1 cupful of non-starchy vegetables per day.

One caveat: the Robert C. Atkins Foundation provided funding for the study. The late Dr. Atkins deserves the credit for initially popularizing the low-carb diet.

The results of the study may surprise the “so-called diabetes experts.” But they probably didn’t surprise the Atkins people and certainly didn’t surprise me one bit.

I’ve lived these diets. For most of my diabetes experience I followed and recommended a low-glycemic diet. I know that eating high-glycemic foods like potatoes or anything made from wheat flour wreaks havoc with my blood glucose levels. But I also know from my own experience of more than a year on a low-carb diet that nothing else offers comparable control.

This article is based on an earlier version of my article published by HealthCentral.

Never Miss An Update

Subscribe to my free newsletter “Diabetes Update”

I send out my newsletter on first of every month. It covers new articles and columns that I have written and important developments in diabetes generally that you may have missed.

Previous Post Next Post

You Might Also Like These Articles

  • David Mendosa at

    Dear Andy,

    No, I have plenty of energy. But please be sure to read http://www.mendosa.com/blog/?p=314

    Best regards,


  • Andy at

    Do find yourself with less energy on a very low carb diet? I am a recently diagnosed type 1 and I’ve been following a very low carb diet. It has worked great for controlling my blood sugars but it feels like I have less energy and I feel a little lethargic. I’m debating adding some low glycemic load carbs to my diet like the chana dal I just discovered via your very helpful website.

  • David Mendosa at

    Dear Bob,

    You don’t need to be much of a cook or a meal planner. In fact, you are better off that way, because then you will eat more simply. I know, because that describes me well too.

    Controlling your diabetes means controlling what you eat, particularly your carbohydrates, which are the foods that will raise your blood glucose levels. If you leave the starchy carbs — the wheat, flour, bread, and other grains as well as the rice — out of your diet, you will have gone a long way toward controlling your diabetes.

    Best regards,


  • Bob at

    I was just diagnosed with type2 in march 2009.
    I have alot to learn. I’m not a great cook or meal planner, so I was wondering what the thoughts were about nutrisystem diabetic meal plans and if they were ok.


  • David Mendosa at

    Dear Pat,

    Your current weight is just fine. You are on the low end of normal on the BMI (Body Mass Index) and that is the most healthy place to be.

    The good veggies are those that I wrote about at http://www.mendosa.com/blog/?p=255

    If you do want to gain a few pounds, nuts, particularly walnuts (which have the best omega 3/omega 6 ratio), would do it.

    Of course, you would want to know about the glycemic index, which is indeed about the good carbs. The good carbs are those that won’t spike our blood glucose levels. You might want to start by reading http://www.mendosa.com/gi.htm

    Best regards,


  • Pat Milstead at

    I am a type 2 diabetic and I have flushed my drugs down the toilet and have done just fine with out them.
    My biggest problem is all the diets and figures are for people over weight. I am 145 lbs and 5′ 10″ and according to the charts my best weight is about 160 to 165.
    I need to maintain my weight yet keep the blood sugars at the proper levels with out losing more weight. I average 100 to about 115 two hrs after eating. I would like to know more about the foods that have good carbs and other foods to help maintain weight.

    Good Blog Keep it up

    Pat Milstead

  • lctcathy at

    I was doing an internet search and stumbled across your blog – glad I did. I’ll definitely be ready more.

    While I am not a diabetic, I am a low carber (Atkins) and know that I’ve dodged that bullet. Sadly, so many people who suffer from type II are being given wrong information and paying for it with their lives.

    Keep putting great information out there. Cheers! Cathy