Aging


Studies that deliberately exclude older adults from their samples render older adults' sexuality invisible. shutterstock

By Sue Malta, University of Melbourne

It is commonly believed that one key issue in brain again is that it becomes less flexible - plastic - and that learning may therefore become more difficult.

A new study contradicts that and shows that plasticity did occur in seniors who learned a task well, it just occurred in a different part of the brain than in younger people.

When many older subjects learned a new visual task, the researchers found, they unexpectedly showed a significantly associated change in the white matter of the brain. White matter is the the brain's "wiring," or axons, sheathed in a material called myelin that can make transmission of signals more efficient. Younger learners, meanwhile, showed plasticity in the cortex, where neuroscientists expected to see it.


If you want to know the secret to a longer life, look to reptiles. But you may not like the answer you find.

There is a belief that a fast-paced lifestyle is damaging to health. Slowing down will not just be more relaxing, but also keep you around, finds an analysis of 1,014 species of reptiles (including 672 lizards and 336 snakes), a representative sample of the approximately 10,000 known reptiles on the planet. After examining their life history parameters, such as body size, earliest age at first reproduction, body temperature, reproductive modes, litter or clutch size and frequency, geographic distribution, and diet, they found that early sexual maturation and a higher frequency of laying eggs or giving birth were associated with shortened longevity. 

Supplement marketers have been aggressively claiming that vitamin B12 and folic acid reduce the risk of memory loss, but a large study on long-term use of supplements found no benefits.   

The study involved people with high blood levels of homocysteine, an amino acid. High levels of homocysteine have been linked to memory loss and Alzheimer's disease. Early observational studies claimed there may be some benefit to thinking and memory skills in taking folic acid and vitamin B12, but the results were not duplicated in later randomized, controlled trials. 


17 genomes of supercentenarians, people living beyond 110 years of age, haven't led us any closer to discovering protein-altering variants significantly associated with extreme longevity, according to a study in PLOS ONE by Hinco Gierman from Stanford University and colleagues.

There are 74 supercentenarians alive worldwide, with 22 in the United States. The authors of this study performed whole-genome sequencing on 17 of them to explore the genetic basis underlying extreme human longevity. 


There's a new reason not to go on a low-fat diet. The signs of brain aging can be postponed in mice if placed on a high-fat diet, which opens up the possibility for treatment of patients with Alzheimer's and Parkinson's disease. 

When we get older, defects begin to develop in our nervous system and our brain loses some of its intellectual capacity. The risk of developing diseases such as Parkinson's and Alzheimer's also increases. Alzheimer's disease is currently the fastest-growing age-related disease.


Each year nearly 2,000,000 Americans suffer osteoporosis-related fractures but after it happens, 53 percent of women received Dual X-ray Absorptiometry, the preferred technique for measuring bone mineral density and therefore osteoporosis, compared with only 18 percent of men. 

As the population ages, fractures are expected to increase dramatically, placing a major burden on the health care system and a new study from Beth Israel Deaconess Medical Center (BIDMC) suggests that bias against men in favor of post-menopausal women will lead to lower quality of care and higher costs.


What are the most important discussions to have among doctors, patients and families?

It seems obvious to just ask but there is a gap between what patients would like and the care they actually receive, according to a paper in the Canadian Medical Association Journal.

Current guidelines list 11 key elements for health care providers to discuss regarding end-of-life care, although these are based mainly on expert opinion and not on patient and family feedback.



It's not all bad news for older brains. Credit: Shutterstock

By Angela Gutchess, Brandeis University

A diet rich in milk products is promoted as strengthening bones and reducing the likelihood of osteoporotic fractures, but dairy lobby marketing aside, actual research related to the benefits of milk for the prevention of fractures or influence on mortality rates has found evidence for and against.
  

A new study finds that high milk intake in women and men is not accompanied by a lower risk of fracture and instead may be associated with a higher rate of death.