Low-Carb Diet Benefits Type 2 Diabetes, Heart Health, Studies Show

Eating a low-carbohydrate diet can have benefits for both Type 2 diabetes and heart health, according to two studies recently published in the journals Diabetes Care and Annals of Internal Medicine, respectively. An estimated 26 million Americans have Type 2, and more than one-third of adults in the United States have at least one form of cardiovascular disease.


The first study, conducted by investigators at the University of Adelaide, Australia, sought to determine the effects of a very-low-carbohydrate, high-unsaturated/low-saturated fat diet (LC) to a high-unrefined-carbohydrate, low-fat diet (HC) on blood glucose control and heart health in people with Type 2 diabetes. The researchers randomly assigned 115 overweight or obese adults with Type 2 diabetes and A1C levels (a measure of glucose control over the previous 2–3 months) of 7% or higher to one of the study diets for a total of 24 weeks.

Although both diets contained the same number of calories, the LC diet was comprised of 14% carbohydrate (with an aim of less than 50 grams per day), 28% protein, and 58% total fat, including 35% monounsaturated fat and 13% polyunsaturated fat, while the HC diet was comprised of 53% carbohydrate with an emphasis on low-glycemic foods, 17% protein, and less than 30% total fat, including 15% monounsaturated fat and 9% polyunsaturated fat. Both diets limited saturated fat to less than 10% of total calories.

In addition to consuming the assigned diets, all subjects also attended 60-minute exercise classes three days a week.

Ninety-three participants completed the study. At the end of the 24-week period, the researchers found that A1C levels had been reduced by an average of 2.6% in the LC group, compared to 1.9% in the HC group. Among participants with baseline blood glucose levels averaging 155 mg/dl or above, the blood glucose reduction was 61 mg/dl in the LC group, compared to 45 mg/dl in the HC group. (The difference in blood glucose reduction was not significant among those with lower baseline levels.) Those in the LC group also saw reduced variations in blood glucose levels and a greater reduction in triglycerides (a type of blood fat), and they were able to stop taking more of their diabetes medicines, compared to participants in the HC group.

“The findings from this study suggest that a novel eating pattern that markedly limits carbohydrates and increases protein and unsaturated fat may have more favorable therapeutic potential for optimizing the management of Type 2 diabetes and reducing cardiovascular disease risk as part of a holistic lifestyle-modification program,” said principal investigator Grant D. Brinkworth, PhD.

The study authors note that sticking to a particular meal plan for the long term is “notoriously difficult” and suggest that further study is necessary to determine whether the beneficial effects of the very-low-carbohydrate, high-unsaturated/low-saturated fat diet are sustained beyond 24 weeks.

The second study was conducted by researchers from the Tulane University School of Public Health and Tropical Medicine to determine the effects of a low-carbohydrate diet compared to a low-fat diet on body weight and heart health. The scientists recruited 148 adults without diabetes or cardiovascular disease, randomly assigning 75 of the participants to a low-carbohydrate diet (defined in this study as less than 40 grams of carbohydrate per day) and 73 of the participants to a low-fat diet (defined as less than 30% of total daily calories coming from fat and less than 7% from saturated fat).

The subjects were given the same instructions regarding dietary fiber and types of fats. They met with dietitians in individual sessions weekly for the first four weeks, then in small groups every other week for the next five months. For the last six months of the study, all participants met in small group sessions monthly.

Fifty-nine people (79%) in the low-carbohydrate group and 60 people (82%) in the low-fat group completed the yearlong study. The researchers found that, compared to those in the low-fat group, the participants in the low-carbohydrate group had significantly greater decreases in body weight and fat mass and increases in lean mass. They also had significantly greater reductions in C-reactive protein levels (a marker of inflammation), estimated 10-year risk for coronary heart disease, triglyceride levels, and ratio of total cholesterol to HDL (“good”) cholesterol. The results were found to apply to both African-American and white participants.

“Our findings suggest that people who want to lose weight and have risk factors for heart disease could consider a low-carbohydrate diet as an option to both lose weight and improve those risk factors,” noted study coauthor Tian Hu, MD, in an interview with Medscape Medical News.

Speaking with Medscape Medical News, Kasia Ciaston, MS, RD, LDN, who was not involved in the research, emphasized that the real message of the study is that getting the right balance in your diet, versus cutting out a particular macronutrient such as carbohydrate or fat, is the most beneficial to health.

For more information, read the articles “Low-Carb, Low-Saturated-Fat Diet Benefits Type 2 Diabetes” and “Heart Disease Risk: Low-Carb Diet Trumps Low-Fat Option” or see the studies’ abstracts in the journals Diabetes Care and the Annals of Internal Medicine. And to learn more about low-carbohydrate diets, see these pieces by nurse David Spero.

What have your experiences been with eating a low-carbohydrate diet? Have you noticed any beneficial effects on your health? Let us know by leaving a comment!

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  • ashley

    I was on the atkins diet and my bad cholesterol went sky high and I had protein in my urine and felt lousy-and had terrible fibromyalgia pain.
    As soon as I added wheat and grains,fruits and veggies back,everything was so much better
    My husband got kidney stones from low carb and 2 friends had to have their gall bladders removed.

  • Richard Myers

    A lot of the recipes in the Oct 2014, are very high in carbs; a lot higher than what I look for in the foods I buy. If a low-carb diet is best for diabetics, why do you publish recipes with such high carbs? I won’t let my wife make this stuff.

  • NoCarbs

    Been on low carb for a few months and my cholesterol and blood sugar numbers have improved. For me it works…so far. Maybe eventually I’ll add back some carbs if my insulin resistance has decreased enough.

  • Phil

    You must also clean the body from deposits and fruit and vegetables are a great fit for this because most of them are alkaline-cleanse the intestines, liver and all the cells in the body. Diet on the plate should be 80-20 or 80% of the products on the basic plate, 20% acidic (the list of products available without a problem on the Internet). I also support alkaline powder therapy daily and I take taxifolin to strengthen capillaries. I recommend.

  • Ralph Pantuso

    I have had Type 2 diabetes for over 10 years and I have maintained and continue to maintain on A1C level of 6 or lower since three months after my initial diagnosis. I have accomplished this by a combination of medication, a low carb diet and exercise.

    The best low carb that I know of is the Diabetes Miracle (http://www.thediabetesmiracle.com/).

    In short: a low carb diet works!

  • Gary Ferrin

    Having faced the obstinacy of nutritionists insisting that I eat a regular pyramid diet but in smaller amounts and more frequently, despite my claims that almost any non fibrous carbs created immediate spikes in my blood sugar, I was happy to see that at last the ADA has come around to realizing low carb diets for type II diabetics is a better approach

    My experience has been that for me ONLY low carb diets work, and offset the weight gain of insulin’s effects, plus don’t tire me out sa my body struggles to absorb the carbs. I eat exclusively greens and protein and fewer calories than recommended for my size. It just works better and I have significantly more energy because my body has less to do.

    Short of reversing the illness, in the interim, at least for now, it’s the only method I’ve found to mitigate the impact of metabolic problems.

    I wish all of us the best of luck with this problem as it’s a giant pain to deal with and unfortunately, becomes the center of our lifestyles.

  • Frank Davinci

    I’ve tried low fat/high carb diets and low carb diets and I have found low carb diets to be the most efficacious for controlling my blood sugar and losing weight. I follow what is called the ketogenic diet currently and have much success.

    RE: Ashley above,

    “The facts are that high-protein diets, when consumed in balance with enough water, fat and fat-soluble vitamins, and nutritional factors from non-starchy vegetables, ARE healthy. “

  • JohnC

    Your summary of the study didn’t say how much management the participants were encouraged to do — like did they even have a glucose meter? The results were predictable, but would have been much better had there not been so much restriction on the types of fat (other than trans fat).

    I have been on a low carb / high fat diet for about 10 years and I can assure you the results are even more pronounced. I’m 70 and in great health (better than 10 years ago) and my A1c is always in the low 5 range.That is better than the 10+ before. I am LADA (T 1.5) and use insulin. With my diet, my weight is normal and I don’t have to worry about calorie counting.

    A bonus with low carb is your blood sugar doesn’t have such drastic swings from high and low readings too. Much easier to maintain close to normal BS readings.

    There is much more to low carb eating than the way this study was carried out.

    I agree with Richard above about some of the recipes posted here — gives me a good laugh with the proclamation, “You’ve got to be kidding”. Who ever designed these recipes is not diabetic or has some serious health problems.

  • Janet

    I read “Dr. Bernstein’s Diabetes Solution” when I couldn’t get my fasting blood sugars down. It is based on low carb eating. It works very well for me. I decreased my medication and when I follow it strictly, my numbers are at non-diabetic levels. I must admit that it is hard to stick to, though I am not really hungry. I do allow myself to cheat on occasion though I know I shouldn’t. I have tried just about everything and low carb works best for me.

  • Beano

    You can eat ANYTHING, high carb, lo carb as long as you do not exceed your required calories.

    If you ate only 3 pieced of cake a day you would not really affect your diabetes and I bet if you did that you would have to cut your insulin by more than half.

    There are only 4 ways to lower readings.

    1. Eat nothing or have water only.
    2. Eat soup.
    3. Eat ONLY a bite or two of ANYTHING.
    4. Eat only vegetables or meat for a meal.

  • Terri

    For once I wish they would stop using the term “low carb”. The stuff diabetics need to avoid like the plague is all that simple stuff, i.e. the flour, sugar, starchy vegetables, rice, etc., (white foodstuffs). There are carbohydrates that are very good for you-VEGETABLES and FRUITS (albeit the fruits high in sugar are best limited). Like Richard Myers, I agree that most of the recipes you post are high in their content of this garbage. The last time I was in the hospital for a hypoglycemic episode, I had to tell them what to give me because that crap they were serving (on the diabetic diet list) me was worse than what I wanted! It’s a racket…

  • Bob P

    I lost 100 lbs 15 years ago on a low carb, high protein, and not so high fat, diet. I could not maintain that diet and have regained the weight.

    I was also taking an oversupply of most all micronutrients (vitamins, minerals and more) during the diet. My carb cravings were mostly suppressed during that year.

    My health improved during that time and I was off my diabetes meds at its end. I believe my cholesterol improved but I do not think I was on cholesterol medications at the time.

    I would like to see more studies of low carb diets and of diets that include micronutrients.

    I would also REALLY like to see studies of diets that restrict Fructose. It should be limited directly and from higher sugars and starches that breakdown into large amounts of Fructose. It is fructose that the liver turns into fat, while glucose goes directly into cells to power them.

    • Lee Frederick Ashcroft

      Read the Atkins diet revolution. It explains how to properly manage this way of eating and keep it up long term.

  • Anup Singh

    Oh I have been on a low carb high fat diet as a diabetic since years like many other diabetics on http://www.forums.dlife.in/ and all markers have improved. My fat includes higher quantity of saturated fat from VCO, eggs etc. The net effect is I haven’t taken any drugs for my T2 and never had to bother about BMI for controling sugar.

    • Sunil Kapoor

      Hi sir, my husband has recently been diagnosed with type 2 diabetes. His hb1ac is 7.2 and his random sugar was 283. I have read a lot about the low carb diet. Can u pls guide me about this diet since I don’t want and pray that he should be put on medicines. Pls guide me about the meal plan and also the ideal fruit and vegetable choices. I shall be extremely grateful for your help. Thanks-Mrs kapoor.

    • Sunil Kapoor

      Hi sir, my husband has recently been diagnosed with type 2 diabetes. His hb1ac is 7.2 and his random sugar was 283. I have read a lot about the low carb diet. Can u pls guide me about this diet since I don’t want and pray that he should be put on medicines. Pls guide me about the meal plan and also the ideal fruit and vegetable choices. I shall be extremely grateful for your help. Thanks-Mrs kapoor.

  • low fat diet control type 2 diabetes, it a 100% right talk and i agree with writer.

  • Chandu Singh

    Diabetes is a silent Killer which weaken the immune system of our body. So a diabetic patient must have to take the balance diet.

  • Vishu Malik

    What are the type of diabetes ?

  • Sajid Akhtar

    can we have sweets in diabetes !!! please provide me a diet chart of diabetes!!!

  • Amit Kumar

    What are the dietary restrictions which should be followed by diabetic patient?

  • Alisha Sharma

    Can diabetes directly cause fatigue with high or low blood sugar levels?

  • Shivi Malik

    Should a diabetic avoid all sugar and carbohydrates?

    • ConroyDawn

      Not all carbohydrates. Colourful vegetables, nuts, some beans and a serving or two of lower carb fruit is okay. If you are not too carb sensitive, a serving of oatmeal or other high fibre grain can be eaten one or two times a day. If you want a potato instead, make it the size of a baby’s fist. Your daily blood tests can give you a good idea of how your body reacts. Avoid the sugar. Sugar is diabetes, strokes and heart attacks in a sweet package.

  • Kamal

    Hi Everyone, What is the difference between type 1 and type 2 diabetes ? Can Anyone briefly this question?