Middle-age adults with excess belly fat now have yet another reason to reduce their waist circumference. Research shows that abdominal obesity nearly triples their risk for dementia. Belly fat is already a known risk factor for diabetes, stroke, hypertension, hyperlipidemia (elevation of lipids such as cholesterol), and heart disease.

Obese people, who have a Body Mass Index (BMI) of 30 or higher, are at increased risk for mental health disorders. Depression and anxiety often lead to an increase risk of obesity, and obesity is common in people with depression. However, even people with normal BMIs who have large abdomens are much more likely to develop dementia.

Abdominal obesity is associated with lower total brain volume in otherwise healthy, middle-age adults, and a smaller brain is associated with a higher risk for subsequently developing dementia. In a study published in May 2010, researchers determined that visceral fat-the fat surrounding our organs-is linked to smaller brain size, more so than subcutaneous fat (fat that lies under our skin).

While the reason for the link is not entirely clear, abdominal fat tissue is metabolically very active. It secretes hormones and inflammatory products that play a role in diabetes and cardiovascular disease. At this point, scientists don't know what specific effect this metabolic activity has on the brain.

There is plenty of good news, however. Abdominal fat responds particularly well to diet and exercise. In fact, there's evidence that we can reduce the risk of developing dementia by 15 to 20 percent by modifying risk factors. Physicians recommend we:

  • Increase exercise,
  • Control midlife obesity ,
  • Optimize midlife blood pressure, and
  • Reduce midlife cholesterol levels.

It's important to implement these lifestyle improvements in or before middle age. High blood pressure, a significant risk factor for heart disease, is associated with an increase risk for Alzheimer's disease, mild cognitive impairment, and vascular dementia. However, there's no evidence that lowering blood pressure or cholesterol later in life will reduce the likelihood of developing dementia.

New research shows that the popular DASH diet (Dietary Approaches to Stop Hypertension), in combination with aerobic exercise and calorie restriction, improves brain functioning among sedentary, overweight, or obese patients with high blood pressure. The DASH diet is a low-sodium, low-fat eating plan. Mediterranean diets, which emphasize plenty of fresh fruits and vegetables, also reduce obesity and related disorders.

It's important to take steps to preserve our brain health if we want to prevent, or reduce our risk of developing, dementia, a progressive and irreversible disease.


Cassels, Caroline. "Central Obesity in Midlife an Independent Risk Factor for Dementia." Medscape Medical News. Web. 27 March 2008. http://www.medscape.com/viewarticle/572067

Harrison, Pam. "Abdominal Obesity Linked to Lower Total Brain Volume in Healthy Middle-Aged Adults." Medscape Medical News. Web. 26 May 2010. http://www.medscape.com/viewarticle/722471

Kelly, Janis. "Mental Health Disorders Strongly Linked to Obesity Risk." Medscape Medical News. Web.

14 August 2009. http://www.medscape.com/viewarticle/707473

Harrison, Pam. "Reduction in Dementia Predicted With Midlife Risk Factor Modification." Medscape Medical News. Web. 2 April 2010. http://www.medscape.com/viewarticle/719688

Anderson, Pauline. "DASH Diet Plus Exercise Improves Cognitive Function in Sedentary Obese Patients." Medscape Medical News. 11 March 2010. http://www.medscape.com/viewarticle/718338