In addition to increasing the risk for heart disease and diabetes, having too much fat around the waist may also be detrimental to the health of your brain. According to a new study published in Neurology, a pot belly in middle age dramatically increases the risk for mental decline in the form of dementia.

Researchers at Kaiser Permanente of Northern California collected the sagittal abdominal diameters (in other words, measurements of how far the pot belly protrudes) of 6583 adults who were between the ages of 40 and 45 from 1964 to 1973. Then, the researchers reviewed the medical records of these adults from 1994 onwards and found that, between January 1995 and June 2006, 1049 of the participants had been diagnosed with dementia. By analyzing the relationship between sagittal abdominal diameter and the development of dementia, the researchers found that the risk of dementia increased with pot belly size, even in participants who were not otherwise overweight.

So, in addition to maintaining a healthy weight, middle-aged adults should be aware of where they carry their weight. An estimated 50% of American adults have increased fat around the waist, also called central obesity. Although there are no studies on the ideal healthy waist circumference, most doctors recommend that men maintain a maximum waist size of 40 inches and the women should keep their waist size at 35 inches or less.