Stress Middle-Age Spread and Alzheimer’s

Forty-year-olds with excess abdominal fat are much more likely to develop Alzheimer’s disease compared to controls without big bellies.  Researchers followed 6,583 men and women aged 40 to 45 who had their belly fat measured during routine physical checkups between 1964 and 1973.  A caliper was used to determine the distance between their backs and the surface of their upper abdomens, with measurements of 10″ or more being classified as high.  Medical records were evaluated three to four decades later when the participants were aged 73 to 87 to determine how many had developed Alzheimer type dementia.  Of the 1,049 such cases identified, those who were obese due to large bellies in their forties were 3.6 times more likely to develop dementia.  Participants with pot bellies had an increased risk for dementia even if their weight was normal and they had no diabetes, hypertension or other health problems.  Women were more likely than men to have abdominal obesity and non-whites, smokers, people with high blood pressure, high cholesterol, diabetes, or who had less than a high school level of education were also at somewhat greater risk.

As noted in prior Newsletters, it has been well established that stress causes the deposition of deep abdominal fat due to increased secretion of cortisol.  Cortisol can also contribute to the memory loss and other cognitive problems seen in dementia.  In addition, autopsy studies have shown that changes in the brain associated with Alzheimer’s disease may start in young to middle adulthood, and that higher abdominal fat in elderly adults was associated with greater brain atrophy.  Having abdominal obesity in mid-life is known to increase the risk of diabetes, stroke and heart attacks.  In contrast peripheral obesity due to excess fat in the buttocks and extremities has an anti-atherogenic effect, possibly because abdominal fat secretes chemicals that promote insulin resistance.  However, this is the first time researchers have demonstrated that increased abdominal fat also increases risk of dementia.  Whether this is merely an associated or causal factor and possible mechanisms of action will be discussed in a future Newsletter. While there is no precise way to translate belly fat measurements into waist circumference, it is generally recommended that the upper girth limit should be 40 inches for men and 35 inches for women.


1.    Whitmer RA, Gustafson DR et al. Central obesity and increased risk of dementia more than three decades later. Neurology, Published online before print March 26, 2008.