Researchers at the Mayo Clinic recently published findings in the Journal of Alzheimer’s Disease, that people 70 years and older who ate the most carbohydrates in relation to protein and fat were at nearly four times the risk of developing mild cognitive impairment. They found that a diet heavy in sugar also raised the risk. In contrast, study participants who ate more protein and fat relative to carbohydrates were less likely to become cognitively impaired.
“We think it’s important that you eat a healthy balance of protein, carbohydrates and fat because each of these nutrients has an important role in the body,” said lead author Rosebud Roberts, MB, ChB.
The study tracked 1,230 people ages 70 to 89. Of that initial pool of participants only the 940 who showed no signs of cognitive impairment were asked to return for follow-up evaluations of their cognitive function.
Four years later, 200 of the 940 were starting to show mild cognitive impairment – problems with language, thinking, judgement, and memory. While everyone with mild cognitive impairment don’t go on to develop Alzheimer’s Disease, many do. Said Roberts, “If we can stop people from developing mild cognitive impairment, we hope we can stop people from developing dementia.”
Interestingly, participants who had the highest carbohydrate intake at the beginning of the study were 1.9 times likelier to develop mild cognitive impairment than those with the lowest intake of carbohydrates. And, participants with the highest sugar intake were 1.5 times likelier to develop mild cognitive than those with the lowest levels.
When total fat and protein intake were factored in, participants with the highest carbohydrate intake were 3.6 times likelier to develop mild cognitive impairment over the four-year period.
It should be noted that the study didn’t break out carbohydrate consumption by type, other than sugar. However, complex carbohydrates that are low in fiber, like pasta and white bread cause spikes in blood sugar because the body quickly converts them into glucose.
Carbohydrates including whole wheat, brown rice, and barley, as well as vegetables and beans are digested more slowly, and have a less dramatic effect on blood sugar – and consequently may be better for the brain….. Tufts Health & Nutrition Update 12/9/13