If increased risk of heart disease, diabetes and joint pain isn’t motivating enough to right-size your food portions, you may owe it to your brain to cut back on calories.

A study released this month that will be presented at the American Academy of Neurology’s annual meeting showed an increased risk of mild cognitive impairment (MCI) in people who consume 2,100 to 6,000 calories a day.

MCI is defined as problems with memory, language and thinking that are noticeable to others and greater than expected for your age and educational level.

Lead researcher Dr. Yonas Geda of the Mayo Clinic in Scottsdale, Ariz., studied 1,233 people ages 70 to 89, 163 of whom, or 13 percent, had MCI. The participants, who lived in the same county in Minnesota, completed questionnaires about their food and drink intake. All were living independently, and researchers visited their homes.

Participants were grouped in three calorie ranges: 600-1,526 a day, 1,562-2,143 a day and 2,143-6,000 a day. The odds of having MCI more than doubled for those in the highest-calorie group when compared to those in the lowest-calorie group. The middle group did not have a significant difference. History of stroke and diabetes, education level and other factors that can affect memory were taken into consideration.

Researchers also found a dose-related response, meaning the more calories people ate, the greater their risk. Further data analysis will answer important questions about the types of foods participants ate and the influence of physical activity on their mental status.

Medications are available for overeating complications such as diabetes and elevated cholesterol, but MCI is more difficult to treat. Why not reduce the risk of all these problems by eating appropriate portions of healthful food?

For someone eating 2,000 calories a day, the recommendation is 4 1/2 cups of fruits and vegetables. When all that delicious produce fills the plate there is just enough room left for the right amount of higher calorie foods. Check out great tips at www.choosemyplate.gov.

Sheah Rarback is a registered dietitian on the faculty of the University of Miami Leonard M. Miller School of Medicine.