With Fat: What's Good or Bad for the Heart, May Be the Same for the Brain

May 18, 2012

Science Daily/Brigham and Women's Hospital

It has been known for years that eating too many foods containing "bad" fats, such as saturated fats or trans fats, isn't healthy for your heart. However, according to new research from Brigham and Women's Hospital (BWH), one "bad" fat -- saturated fat -- was found to be associated with worse overall cognitive function and memory in women over time. By contrast, a "good" fat -- mono-unsaturated fat was associated with better overall cognitive function and memory.

The research team analyzed data from the Women's Health Study -- originally a cohort of nearly 40,000 women, 45 years and older. The researchers focused on data from a subset of 6,000 women, all over the age of 65. The women participated in three cognitive function tests, which were spaced out every two years for an average testing span of four years. These women filled out very detailed food frequency surveys at the start of the Women's Health Study, prior to the cognitive testing.

"When looking at changes in cognitive function, what we found is that the total amount of fat intake did not really matter, but the type of fat did," explained Olivia Okereke, MD, MS, BWH Department of Psychiatry.

Women who consumed the highest amounts of saturated fat, which can come from animal fats such as red meat and butter, compared to those who consumed the lowest amounts, had worse overall cognition and memory over the four years of testing. Women who ate the most of the monounsaturated fats, which can be found in olive oil, had better patterns of cognitive scores over time.

"Our findings have significant public health implications," said Okereke. "Substituting in the good fat in place of the bad fat is a fairly simple dietary modification that could help prevent decline in memory."

Okereke notes that strategies to prevent cognitive decline in older people are particularly important. Even subtle declines in cognitive functioning can lead to higher risk of developing more serious problems, like dementia and Alzheimer disease.

http://www.sciencedaily.com/releases/2012/05/120518081358.htm

Trouble Sleeping? It May Affect Your Memory Later On

February 14, 2012

Science Daily/American Academy of Neurology

The amount and quality of sleep you get at night may affect your memory later in life, according to research that was recently released and will be presented at the American Academy of Neurology's 64th Annual Meeting in New Orleans April 21 to April 28, 2012.

"Disrupted sleep appears to be associated with the build-up of amyloid plaques, a hallmark marker of Alzheimer's disease, in the brains of people without memory problems," said study author Yo-El Ju, MD, with Washington University School of Medicine in St. Louis and a member of the American Academy of Neurology. "Further research is needed to determine why this is happening and whether sleep changes may predict cognitive decline."

Researchers tested the sleep patterns of 100 people between the ages of 45 and 80 who were free of dementia. Half of the group had a family history of Alzheimer's disease. A device was placed on the participants for two weeks to measure sleep. Sleep diaries and questionnaires were also analyzed by researchers.

After the study, it was discovered that 25 percent of the participants had evidence of amyloid plaques, which can appear years before the symptoms of Alzheimer's disease begin. The average time a person spent in bed during the study was about eight hours, but the average sleep time was 6.5 hours due to short awakenings in the night.

The study found that people who woke up more than five times per hour were more likely to have amyloid plaque build-up compared to people who didn't wake up as much. The study also found those people who slept "less efficiently" were more likely to have the markers of early stage Alzheimer's disease than those who slept more efficiently. In other words, those who spent less than 85 percent of their time in bed actually sleeping were more likely to have the markers than those who spent more than 85 percent of their time in bed actually sleeping.

"The association between disrupted sleep and amyloid plaques is intriguing, but the information from this study can't determine a cause-effect relationship or the direction of this relationship. We need longer-term studies, following individuals' sleep over years, to determine whether disrupted sleep leads to amyloid plaques, or whether brain changes in early Alzheimer's disease lead to changes in sleep," Ju said.

"Our study lays the groundwork for investigating whether manipulating sleep is a possible strategy in the prevention or slowing of Alzheimer disease."

http://www.sciencedaily.com/releases/2012/02/120214171036.htm

Memory May Decline Rapidly Even in Stage Before Alzheimer's Disease

March 23, 2010

Science Daily/American Academy of Neurology

Memory and thinking skills may decline rapidly for people who have mild cognitive impairment, which is the stage before Alzheimer's disease when people have mild memory problems but no dementia symptoms, and even more rapidly when dementia begins, which is when Alzheimer's disease is usually diagnosed.

"These results show that we need to pay attention to this time before Alzheimer's disease is diagnosed, when people are just starting to have problems forgetting things," said study author Robert S. Wilson, PhD, of Rush University Medical Center in Chicago.

"The changes in rate of decline occur as the brain atrophies due to the disease, first mainly in the hippocampus during the initial symptomatic stage, referred to as mild cognitive impairment, then in the temporal, parietal and frontal cortex during the dementing illness phase of Alzheimer's disease," said David S. Knopman, MD, of the Mayo Clinic in Rochester, Minn., and Fellow of the American Academy of Neurology, who wrote an editorial accompanying the article.

http://www.sciencedaily.com/releases/2010/03/100322171008.htm