Smoking, Diabetes, Obesity May Shrink Your Brain
Study adds to evidence that good living preserves mental abilities.
By Maureen Salamon, HealthDay
MONDAY, Aug. 1 (HealthDay News) — As if there weren't
already enough good reasons to avoid smoking and keep your weight,
blood sugar levels and blood pressure all under control, a new study suggests
these risk factors in middle age may cause your brain to shrink, leading to
mental declines up to a decade later.
Evaluating data from 1,352 participants whose average age was 54 in the
Framingham Offspring Study -- which began in 1971 -- researchers from the
University of California, Davis found that smoking, high blood pressure, diabetes and
being overweight were each linked to potentially dangerous vascular changes in
"We can't cure disease or cure aging, but the idea of a healthy body, healthy
mind is very real," said study author Dr. Charles DeCarli, director of UC Davis'
Alzheimer's Disease Center. "People should stop smoking, control their blood
pressure, avoid diabetes and lose weight. It seems like a no-brainer."
The study is published Aug. 2 in the journal Neurology.
Participants were given blood pressure, cholesterol and diabetes tests and had their body
mass and waist circumference measured. They also underwent MRI brain scans over
the course of a decade, the first one about seven years after the initial risk
Those with stroke and dementia were excluded at the outset, and between the
first and last MRIs 19 participants suffered a stroke and two developed
Those with high blood pressure experienced a more rapid worsening of test
scores of planning and decision-making, which corresponded to a faster rate of
growth of small areas of vascular brain damage than those with normal blood
Those with diabetes in middle age experienced brain shrinkage in an area
known as the hippocampus faster than those without, and smokers lost brain
volume overall and in the hippocampus faster than nonsmokers, with a more rapid
increase of small areas of vascular brain damage.
Meanwhile, participants who were obese at middle age were more likely to be
in the top 25 percent of those with faster declines in tests of executive
function, DeCarli said. Those with a high waist-to-hip ratio were more likely to
be among the 25 percent with a faster drop in brain volume.
"I do think it's an important study and has practical importance in
confirming there are things we can do in middle age that can have effects 10, 20
and 30 years down the line to improve cognitive health," said Dr. Raj Shah,
medical director of the Rush Memory Clinic in Chicago. "It may seem we're
talking about things that are somewhat common knowledge, but really, we always
hypothesize these things could happen, but to show they actually do in a study
is very important."
DeCarli noted that the effects of the risk factors studied are likely to be
even more compelling in the general population, since study participants were
largely healthy individuals with normal blood pressure and cholesterol levels and a low
"It could be so much worse in a representative group of Americans," he said,
adding that all study participants were white and only 5 percent were diabetics,
compared to a nearly 50 percent rate for Hispanics over age 65. And, "the study
certainly doesn't represent the growing obesity problem seen in the South."
One of the strengths of the research was that it used a large sample of
people from a well-known study, said Catherine Roe, an assistant professor of
neurology at Washington University School of Medicine in St. Louis. However, the
results don't prove these risk factors caused the brain changes, she added.
"We know smoking and being overweight are bad for other parts of your
health," Roe said. "This is just one more reason to get these things under