The Carbohydrate Brain Fuel Myth

We distort knowledge faster than things. Some things are so easy to assemble that "even a child can do it" in outer space. But even children know that information disassembles all too readily.

Children learn by playing the game of telephone that information gets garbled as it gets passed along. Too bad that medical writers don't know that basic lesson.

That's why that although I am also a medical writer about diabetes, I don't ask you to trust me. Unlike almost everyone who prepares medical articles for the Internet, I link the primary sources so you can see that it's not just my opinion or a secondary source that other medical writers at secondary sources like Reuters Health write.

In the children's game of telephone cumulative errors from mishearing often result in what the last player hears isn't anything like the way it started. This can amuse children. But it can lead us seriously astray. The brain fuel myth can lead those of us who have diabetes to a diet far too high in carbohydrates.

If the people who say that our brains need at least 130 grams of available carbohydrate per day to work properly were correct, then nothing you read here can make any sense. For about half a year I have been getting only about a third of that amount.

You can read -- but don't swallow -- what Edutopia Magazine writes about our carbohydrate requirements. "To achieve and maintain normal brain function, adults and children need 130 grams of carbohydrates a day," some freelance medical writer named Abby Christopher writes there.

She even quotes Diane Stadler, research assistant professor in the Oregon Health and Science University's health promotion and sports medicine division to that effect. "Restricting carbs like [the Atkins Diet ] is going to have an effect on the brain," Ms. Stadler told her.

Closer to home is a comment by a Certified Diabetes Educator to one of my articles here. "Remember that the brain does need 130 grams of carbs per day for healthy function," she writes.

Even more grievous is the American Diabetes Association's intermediate oversimplification. While the ADA isn't as ridiculously wrong as the Edutopia Magazine article and that CDE, some people still believe what the largest diabetes charity organization tells us.

"The recommended dietary allowance (RDA) for digestible carbohydrate is 130 grams per day," says the ADA's latest position statement on its "Nutrition Recommendations. Why do we need so much carbohydrate?

The RDA is based, the ADA says,  "on providing adequate glucose as the required fuel for the central nervous system without reliance on glucose production from ingested protein or fat."

Ah! So it's at least 130 grams of glucose per day that our brain needs! And glucose just ain't the same thing as carbohydrate.

I really don't know about fat. But we have known for years that our bodies are very efficient at turning protein into glucose.

In fact, I give the ADA credit for citing the primary source in its "Nutrition Recommendations." That source is a report by the Institute of Medicine's food and nutrition board titled Dietary Reference Intakes: Energy, Carbohydrate, Fiber, Fat, Fatty Acids, Cholesterol, Protein, and Amino Acids. The National Academies Press in 2002 published this book. While the ADA fails to provide a link,  fortunately for those of us who like to go to primary sources you can find it online.