Study: Dietary Choices May Influence Development of MCI

by Dorian Martin Patient Advocate

So here's a new reason to really watch your diet - the types of food that you eat, especially when you're older - may make a difference on whether you develop mild cognitive impairment (MCI), which is often an early stage of Alzheimer's.

Researchers from the Mayo Clinic found that people who are 70 years old and above are four times more likely to develop MCI if they eat a diet high in carbohydrates. Additionally, this group's risk for MCI also increases with a sugar-laden diet. However, people who consume more protein and fat than carbohydrates are less likely to develop cognitive impairment.

In this study, researchers followed 1,230 people between the ages of 70-89. These study participants provided information about their diet during the previous year and also had their cognitive function evaluated by an expert panel of physicians, nurses and neuropsychologists. The panel identified 940 participants who were not showing signs of MCI. This subgroup was asked to return periodically so their cognitive function could be reevaluated.
The researchers found that by four years into the study, 200 of the 940 participants were starting to show signs of MCI, including issues with memory, language, thinking and judgment. These changes were greater than normal changes in brain function due to age.

The researchers' analysis found that the participants who consumed the highest intake in carbohydrates at the beginning of the study were slightly less than two times more likely to develop MCI that participants who consumed the lowest amount of this type of food. And participants who had the highest sugar intake were one-and-a-half times more likely to display symptoms of MCI than those who consumed the lowest levels.

And interestingly, participants who ate the highest amount of fat were 43 percent less likely to develop MCI than those who ate the lowest amounts. Furthermore, participants who ate the highest amount of protein were 21 percent less likely to get MCI than people who ate the highest amount. Finally, the researchers found that when total fat and protein consumption were considered, participants who had consumed the most carbohydrates were 3.6 times likelier to develop MCI symptoms.

A high carbohydrate intake could be bad for you because carbohydrates impact your glucose and insulin metabolism," said Dr. Rosebud Roberts, an epidemiologist at the Mayo Clinic who was the study's lead author. "Sugar fuels the brain so moderate intake is good. However, high levels of sugar may actually prevent the brain from using the sugar similar to what we see with type 2 diabetes." Dr. Roberts encouraged people to eat a diet that has a healthy balance of protein, carbohydrates and fat, since each food type serves a different function for the body.

However, cutting out all carbs could be problematic since these food fuel the body so it can undertake physical activity and maintain optimal organ function. However, the Harvard School of Public Health recommends opting for healthy carbohydrates. These foods include whole grains (preferably less processed), vegetables, fruits and beans. Avoid white bread, white rice, pastries, sugar sodas and highly processed foods.

The Harvard website recommends five ideas for adding the good types of carbohydrates to your daily meals. These include:

  • Opt for whole grains at breakfast, such as a bowl of steel cut oats or a cold cereal that identifies a whole grain first on the list of ingredients while also being low in sugar.

  • Eat whole grain breads -- such as whole wheat, whole rye or another type of whole grain -- for lunch or as snacks.

  • Substitute brown rice, bulgur, wheat berries, whole wheat pasta or another whole grain in place of potatoes.

  • Eat a piece of fruit instead of drinking juice. Whole fruit has more fiber and less sugar than juice.

  • Eat more beans, which are a source of both slowly digest carbohydrates and protein.

Primary Sources for This Sharepost:

Harvard School of Public Health. (nd). The nutrition source: Carbohydrates.

Mayo Clinic. (2012). Eating lots of carbs, sugar may raise risk of cognitive impairment, Mayo Clinic study finds.

Dorian Martin
Meet Our Writer
Dorian Martin

Dorian Martin writes about various topics for HealthCentral, including Alzheimer’s disease, diet/exercise, menopause and lung cancer. Dorian is a health and caregiving advocate living in College Station, TX. She has a Ph.D. in educational human resource development. Dorian also founded I Start Wondering, which encourages people to embrace a life-long learning approach to aging. She teaches Sheng Zhen Gong, a form of Qigong. Follow Dorian on Twitter, Facebook or Instagram at @doriannmartin.