Forget the Second Helping: Link Discovered Between Calories and Memory

by Carole Jackson, Bottom Line Health

If I had a nickel for every time I heard someone say, “Oh man, I ate too much. I shouldn’t have had that second serving,” I would have quite a few nickels!

Obviously, excessive eating is no good for your waistline…neither are all of the associated ailments of obesity. But, it gets worse. All that overeating actually may be making you forgetful. According to a new study—it can double the risk for memory loss. In other words, how much you put into your stomach greatly affects your brain.

I checked out the research to find out just how many extra calories put us at risk…


While past studies have suggested that caloric intake is linked to Alzheimer’s disease, this report was one of the first to examine whether there is a link between high-caloric intake and a less severe form of memory loss called mild cognitive impairment (MCI). MCI is more than just age-related forgetfulness—it’s a bit more serious. People with MCI are generally able to function normally, but they might occasionally forget an event from the recent past or a future engagement. People with MCI, for example, may not be able to recall what they had for dinner the night before or they may forget about a planned trip later in the day.

The study included 1,233 men and women without Alzheimer’s between the ages of 70 and 90. Participants completed a questionnaire, which asked how much of specific foods and drinks they consumed and how often they consumed them, on average. Researchers used that information to calculate the caloric quantity each person consumed—they did not examine caloric quality (carbs, fats, protein, etc). Then researchers divided the participants into three equal-sized groups that represented the lowest, moderate and highest calorie intake. Each group contained both men and women. The first group consumed between 600 and 1,525 calories per day (the low-intake group)…the second group consumed between 1,526 and 2,142 calories per day (the moderate-intake group)…and the final group consumed more than 2,142 calories per day (the high-intake group). Later, an expert panel reviewed the brain function of the participants and 163 were classified as having MCI.

The researchers found that people in the high-intake group (those who ate more than 2,142 calories per day) had a significantly higher risk for MCI, with double the risk compared to the low-intake group. The results remained the same even after accounting for gender, body mass index, history of stroke and other risk factors. People in the low-intake and moderate-intake groups did not have a significantly higher risk for MCI.

To learn more about the findings, I called the lead author, Yonas E. Geda, MD, an associate professor of neurology and psychiatry at the Mayo Clinic in Scottsdale, Arizona. His research was presented in April at the annual meeting of the American Academy of Neurology in New Orleans.


Dr. Geda explained that although the study didn’t try to answer the question of why more calories raise the risk for memory loss, one possibility is that consuming more calories increases the body’s production of reactive oxygen species (molecules containing oxygen). These cause damage to cell structure (oxidative stress), and that can lead to changes in the brain that affect memory.

So what’s the magic number of calories that you should try to stay under each day?

You might look at this study and assume that it’s 2,143 calories, but it’s important to remember that the study was looking only at people over the age of 70. Your age andyour activity level—as well as your gender, height and weight—can all affect how many calories you need, said Dr. Geda, so it’s best to figure out how many you need for energy and then make sure that you don’t go over that maximum. To figure out how many calories you need, follow this link from the Baylor College of Medicine:

Source: Yonas E. Geda, MD, associate professor, neurology and psychiatry, Mayo Clinic, Scottsdale, Arizona.