Carbs vs. Fats—Who’s to Blame?

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Last week, Bluebird commented: "I just got the book [Dr. Richard Bernstein’s book Diabetes Solution] and already what he says makes sense to me. My blood glucose counts…keep inching up. …What is your experience with Dr. Bernstein?"

Thanks, Bluebird. I’ve been meaning to write about this issue since I read this entry from fellow blogger Jan Chait on Aug. 28:

“Hubby stopped by the spaghetti take-out place Thursday evening and brought home a bucket of spaghetti plus a loaf of garlic bread for dinner. I love pasta and I love garlic bread. So I ate pasta with fatty sauce. And I ate uncounted amounts of bread slathered with garlic-infused butter. My blood glucose didn’t totally come back down until Saturday. …[This] emphasized what dietary fat can do to blood glucose control.”

I left this comment on the post: “I don’t see where fats came into this at all. You ate a ton of carbs—pasta and bread. That’s almost certainly what raised your sugars.”

Jan commented back: “It wasn’t that my blood glucose merely soared—it was that it stayed elevated. …Had I eaten the same amount of carbs without the fat, say in a giant fresh fruit salad, my numbers would have come right back down.”

Maybe Jan is reporting the official American Diabetes Association position. The ADA’s document “The Diabetes Food Pyramid” says: “Eat more whole grains! Whole grains and starches are good for you because they have very little fat, saturated fat, or cholesterol. …Yes, foods with carbohydrate—starches, vegetables, fruits, and dairy products—will raise your blood glucose more quickly than meats and fats, but they are the healthiest foods for you. Your doctor may need to adjust [read “raise” – DS] your medications when you eat more carbohydrates.”

Dietary Malpractice
For my book, Diabetes: Sugar-coated Crisis, I interviewed Drs. Lois Jovanovic and Richard Bernstein about how insane and harmful this advice is. Jovanovic calls it “malpractice.”

Because of insulin resistance and/or lack of insulin, people with diabetes cannot handle carbs well. Eating carbs raises your blood glucose, period. I believe that, in all probability, Jan’s blood glucose didn’t stay up so long because of the fats she ate, but because there were so many refined carbs in her system that her body could not regulate them. (Spaghetti and garlic bread are not whole grains, either.) For a person with diabetes, eating a big pile of spaghetti or several pieces of white bread is one of the most destructive things they can do, in my opinion. Fats are secondary.

Why does the ADA give such potentially lethal dietary advice? About 40 years ago, scientists discovered that most people who died from diabetes died from heart attacks and strokes. They started recommending low-fat diets to reduce blood vessel damage, because that was mainstream thinking at the time. But if you’re not eating fats, you have to get your calories from somewhere. So the ADA recommended lots of carbs.

But since then, the Diabetes Control and Complications Trial (DCCT) and United Kingdom Prospective Diabetes Study (UKPDS) conclusively proved that high blood glucose, not fats, is the biggest cause of blood vessel damage. And carbs, not fats, cause high blood glucose. So why hasn’t the ADA changed its tune? Most likely, it doesn’t want to admit a mistake, especially one that has probably killed many thousands of people. Dr. Bernstein told me that the advice “probably wouldn’t change until everyone involved in promoting it has died.”

The ADA’S Response
I asked ADA Science Officer Dr. Richard Kahn about the carb controversy. He said, “We don’t have enough data, and it’s very difficult to study long-term effects of dietary changes in the real world, where people often don’t know exactly what they’re eating.”

But if it’s so hard to do good studies, what is the old advice based on? And if we can’t get reliable studies, how will the ADA’s recommendations ever change?

Of course, there’s more to it than fats vs. carbs. Physical activity also plays a huge role—if you move enough, you can eat more carbs. Whole grains are better than refined grains, and unsaturated fat is usually better than saturated fat (and much better than trans fat, which is found in the “partially hydrogenated” oils). As Dr. Kahn says, individuals are different, and the best diet for each person may be different, too. You have to check and see how different foods affect your own blood glucose levels.

I’ve talked with dozens of people with poorly-controlled diabetes who achieved great control when they went to a low-carb diet. Be aware that you may need to reduce your doses of diabetes drugs if you start eating fewer carbs.

PLEASE, readers—let the community know what you think about this issue. What has been your experience? What have you been told? Comment here or see me at

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