A new study, involving 1,219 dementia-free older adults (65+), has found that the more omega-3 fatty acids the person consumed, the lower the level of beta-amyloid in the blood (a proxy for brain levels). Consuming a gram of omega-3 more than the average per day was associated with 20-30% lower beta-amyloid levels. A gram of omega-3 equates to around half a fillet of salmon per week.
Here’s a different aspect to cognitive reserve. I have earlier reported on the first tranche of results from this study. Now new results, involving 246 older adults from the Rush Memory and Aging Project, have confirmed earlier findings that having a greater purpose in life may help protect against the brain damage wrought by Alzheimer’s disease.
Women who received a once-standard type of chemotherapy regimen for breast cancer between 1976 and 1995 have been found to score worse on cognitive tests than women who never had cancer. Specifically, they tended to have lower scores on tests of immediate and delayed verbal memory, executive function, information processing speed, and psychomotor speed. The difference was comparable to some six years of age-related decline.
A study involving 130 HIV-positive people has found that memory impairment was associated with a significantly larger waistline.
Some 40% of participants (average age 46) had impaired cognition. This group had an average waist circumference of 39 inches, compared to 35 inches for those without such problems. Memory impairment was also linked to diabetes in those older than 55 (15% of those with memory problems had diabetes compared to only 3% of those without memory problems).
A study involving 1,575 older adults (aged 58-76) has found that those with DHA levels in the bottom 25% had smaller brain volume (equivalent to about 2 years of aging) and greater amounts of white matter lesions. Those with levels of all omega-3 fatty acids in the bottom quarter also scored lower on tests of visual memory, executive function, and abstract thinking.
The finding adds to the evidence that higher levels of omega-3 fatty acids reduce dementia risk.
The first study to look at the effects of the drug ecstasy on infant development has shown that infants exposed to ecstasy before they were born tend to be behind, especially in motor and coordination skills, at four months.
A new study explains how marijuana impairs working memory. The component THC removes AMPA receptors for the neurotransmitter glutamate in the hippocampus. This means that there are fewer receivers for the information crossing between neurons.
The research is also significant because it adds to the growing evidence for the role of astrocytes in neural transmission of information.