After publication, Dr. David Perlmutter’s book, Grain Brain: The Surprising Truth about Wheat, Carbs and Sugar – Your Brain’s Silent Killers, sat at No. 1 on The New York Times bestseller list for 45 weeks.
What made it such an instant hit? How, exactly, does gluten consumption affect your brain and does it really increase your risk of Alzheimer’s disease or dementia?
What is Gluten?
Gluten is a protein composite found in grains such as wheat, barley and rye. It is abundant on the supermarket shelves since it’s in almost all breads, pastries, imitation meats, ice cream, soy sauce and beer.
During a December, 2013 interview with Dr. James Hamblin in The Atlantic, “This Is Your Brain on Gluten,” Dr. Perlmutter said, “Most grain foods, whether we’re talking about quinoa, amaranth, the very popular grains of the day, the reality is they still are associated with a carbohydrate surge. They have a fairly high glycemic index, meaning that after 90 to 120 minutes, your blood sugar is going to go up, and that is detrimental to the brain.”
What This Means
Blood sugar that is not stabilized can have an adverse impact on the brain. Some reports say the damage may contribute to the development of dementia or similar conditions.
The New England Journal of Medicine published a diabetes-based study, Glucose Levels and Risk of Dementia, that involved over 2,000 individuals who did not have a dementia diagnosis at enrollment. The researchers took note of each person’s health, including blood pressure, activity level and whether or not they had any other major medical condition (such as diabetes or coronary disease).
Over the course of almost seven years, 524 of the individuals who participated in the study developed dementia. These participants tended to have higher blood glucose levels in the half-a-decade preceding the onset of dementia than those who did not develop dementia.
This led researchers to conclude “that higher glucose levels may be a risk factor for dementia.”
Indeed, Dr. Richard O’Brien, chair of neurology at Johns Hopkins Bayview Medical Center in Baltimore, who was not involved in the research, pointed out in WebMD, that the risk increases tied to rising blood sugar (or blood glucose) levels was low compared to other risk factors for dementia.
Parsing pop science
The Hamblin article debunked some of the broad statements – including Dr. Perlmutter’s assertion that many respected peer-reviewed studies had proven that gluten causes dementia. (Alzlive recommends you to read the Atlantic feature in its entirety.) The story made a splash in the world of nutrition science.
When Dr. Perlmutter was interviewed in January, 2014, for Medscape, he recanted slightly on his claim that the link between gluten and dementia was absolute.
Dr. Bret Stetka pointed out that a large number of the studies Dr. P. cited made correlations between gluten and dementia, but did not actually establish cause and effect. His response? “You are 100% correct. … there’s no smoking gun here.”
Hamblin’s takeaway?
“We’ll hear more about the role of blood sugar in Alzheimer’s and continue to focus on moderating intake of refined carbohydrates.”
But don’t believe everything you read.
Christina DeBusk is a freelance writer based in North Branch, Michigan.