Take a Brisk Walk -- It's Good for the Brain

The health benefits of walking are so well known that a fifth-grader could probably recite them. A daily dose of 30 minutes of brisk walking is good for your heart, lungs, muscles, blood pressure and bones.

Now we find out it's also good for your brain.

A study released last month by researchers at the University of Pittsburgh shows that walking a few miles per week can stave off the progress of Alzheimer's disease. According to the BBC, the study proves that "people who walk at least [5 miles] a week have bigger brains, better memories and improved mental ability compared to those who are more sedentary."

This follows an earlier study released in August. Led by Dr. Arthur F. Kramer, researchers from the University of Illinois at Urbana-Champaign have shown that walking not only builds up your muscles, but also builds up the connectivity between brain circuits. This is important because as we age, the connectivity between those circuits diminishes and affects how well we do every day tasks, such as driving. But aerobic exercise, such as brisk walking, helps revive those flagging brain circuits. "Almost nothing in the brain gets done by one area -- it's more of a circuit," Kramer explained to ScienceDaily. "These networks can become more or less connected. In general, as we get older, they become less connected, so we were interested in the effects of fitness on connectivity of brain networks that show the most dysfunction with age."

Neuroscientists have identified several distinct brain circuits, and one of the most intriguing is the default mode network (or DMN), which dominates brain activity when a person is least engaged with the outside world -- either passively observing something or simply daydreaming. Previous studies found that a loss of coordination in the DMN is a common symptom of aging and in extreme cases can be a marker of disease.

The study: For one year, Kramer's team followed 70 adults who ranged in age from 60 to over 80 years old. All of them were sedentary before the study began. The participants were divided into two groups. One did aerobic walking, while the others served as a control group that did toning, stretching and strengthening exercises.

Brain function was measured using functional magnetic resonance imaging (fMRI) to examine brain networks and determine whether aerobic activity increased connectivity in the DMN or other brain networks. The researchers measured participants' brain connectivity and performance on cognitive tasks at the beginning of the study, at six months and after a year of either walking or toning and stretching. A group of young adults, ages 20 to 30, was also tested for brain function for comparison.

The results: Those who walked briskly reaped the biggest benefits -- and not just physically, Kramer writes in the journal Frontiers in Aging Neuroscience. As the older people became more fit, the aerobic exercise actually improved their memory, attention and several other cognitive processes. In fact, the coherence among different regions in the brain networks increased so much, it actually mimicked that of the 20-somethings.

Specifically, at the end of the year, DMN connectivity was significantly improved in the brains of the older walkers, but not in the stretching and toning group. The walkers also had increased connectivity in parts of another brain circuit called the fronto-executive network, which aids in the performance of complex tasks, and they did significantly better on cognitive tests than did their toning and stretching peers.

Kramer says even moderate aerobic exercise will enhance the function of specific brain structures and improve the coordination of important brain networks. But it must be aerobic to work. Toning and stretching aren't enough to reap the benefits.

"The higher the connectivity, the better the performance on some of these cognitive tasks, especially the ones we call executive control tasks -- things like planning, scheduling, dealing with ambiguity, working memory and multitasking," Kramer said. These are the very skills that tend to decline with aging, he said.

The gotcha: It doesn't happen overnight. It took a full year of walking for the results to be seen. Even the six-month test results showed no significant brain changes. The group that did the stretching exercises saw no cognitive benefit.

This isn't the first study to reach this conclusion. Recent research from the Harvard School of Public Health tracked more than 18,000 women ages 70 to 81 and concluded that the more active we are, the better our cognition. Specifically, walking one-and-a-half hours a week at a pace of one mile in 16-20 minutes gives the full cognitive benefits.

Walking may just be the wonder drug of old age.

B-vitamins may slow onset of Alzheimer’s disease

Large doses of B-vitamins could slow the cognitive decline in older people that is the precursor to dementias such as Alzheimer’s disease, according to a study.

Speaking at the British Science Festival in Bradford on Tuesday, Celeste de Jager, a neuropsychologist at Oxford University, said that taking vitamins B6, B12 and folic acid in medicinal quantities reduced the overall shrinkage of a person's brain by 30% over the course of the two-year study.

Her work, published in the International Journal of Geriatric Psychiatry, was carried out on 270 men and women over 70 who had mild cognitive impairment (MCI), a condition that affects one in six elderly people and which can interfere with memory, language and other mental functions. About half of the people with MCI go on to develop Alzheimer's within five years of the initial diagnosis.

Taking B vitamins and folic acid is known to control the levels of an amino acid called homocysteine in the blood. High levels of this chemical can damage blood vessels and are associated with increased risk of dementia.

"High homocysteine is a known risk factor for cognitive decline in the elderly and Alzheimer's disease and also for other kinds of dementia like vascular dementia," said de Jager. "It can be damaging to the endothelial lining of the blood cells. It also binds to receptors in the brain that are on the neurons and it seems to contribute the atrophy that's associated with Alzheimer's."

The elderly are more susceptible to this effect of high homocysteine, she added, because levels rise with older age, possibly due to poorer absorption of B vitamins in diet as people age.

To keep homocysteine levels down, she said, people should eat more meat, fish and green vegetables, and reduce consumption of alcohol, which is known to deplete the body of vitamin B12.

Across the whole group, de Jager found that the people taking vitamins had a 30% reduced decline in brain tissue over two years compared with placebo. In people with the highest homocysteine levels in the blood at the start of the experiment, however, the vitamins provided most benefit, reducing brain shrinkage by 50% in these cases.

Coffee Linked to Lower Dementia Risk

Drinking coffee may do more than just keep you awake. A new study suggests an intriguing potential link to mental health later in life, as well.

A team of Swedish and Danish researchers tracked coffee consumption in a group of 1,409 middle-age men and women for an average of 21 years. During that time, 61 participants developed dementia, 48 with Alzheimer’s disease.

After controlling for numerous socioeconomic and health factors, including high cholesterol and high blood pressure, the scientists found that the subjects who had reported drinking three to five cups of coffee daily were 65 percent less likely to have developed dementia, compared with those who drank two cups or less. People who drank more than five cups a day also were at reduced risk of dementia, the researchers said, but there were not enough people in this group to draw statistically significant conclusions.

Dr. Miia Kivipelto, an associate professor of neurology at the Karolinska Institute in Stockholm and lead author of the study, does not as yet advocate drinking coffee as a preventive health measure. “This is an observational study,” she said. “We have no evidence that for people who are not drinking coffee, taking up drinking will have a protective effect.”

Dr. Kivipelto and her colleagues suggest several possibilities for why coffee might reduce the risk of dementia later in life. First, earlier studies have linked coffee consumption with a decreased risk of type 2 diabetes, which in turn has been associated with a greater risk of dementia. In animal studies, caffeine has been shown to reduce the formation of amyloid plaques in the brain, one of the hallmarks of Alzheimer’s disease. Finally, coffee may have an antioxidant effect in the bloodstream, reducing vascular risk factors for dementia.

Dr. Kivipelto noted that previous studies have shown that coffee drinking may also be linked to a reduced risk of Parkinson’s disease.

The new study, published this month in The Journal of Alzheimer’s Disease, is unusual in that more than 70 percent of the original group of 2,000 people randomly selected for tracking were available for re-examination 21 years later. The dietary information had been collected at the beginning of the study, which reduced the possibility of errors introduced by people inaccurately recalling their consumption. Still, the authors acknowledge that any self-reported data is subject to inaccuracies.

Fish Oil Supplements May Not Slow Alzheimer's

(HealthDay News) -- One of the main components of fish oil doesn't help slow the development of symptoms in patients with early Alzheimer's, although experts aren't ruling out the possibility that supplementation given earlier might help prevent the disease.

The supplement, docosahexaenoic acid (DHA), is present in abundance in the brain and previous studies had suggested it might play a role in treatment.

But that turned out not to be the case in this latest study, which was funded by the U.S. National Institute on Aging and appears in the Nov. 3 issue of theJournal of the American Medical Association.

"Unfortunately, we have a very solid, but very negative, result that DHA supplementation did not slow the progression of Alzheimer's disease," study author Dr. Joseph Quinn said during a Tuesday news conference. "It's not going to help once a patient has already reached the point where they're able to be diagnosed with Alzheimer's disease. Maybe the study just started the treatment too late."

Quinn, who is assistant professor of neurology at Oregon Health and Science University in Portland, could not say at what age DHA supplementation might provide a benefit. Prevention trials have not been done yet.

Duffy MacKay, vice president of scientific and regulatory affairs at the Council for Responsible Nutrition, a group representing the supplements industry, pointed out that the length of the study was short (18 months), that participants were taking small amounts of DHA and that they weren't taking another important component of fish oil, eicosapentaenoic acid (EPA).

EPA is virtually absent in the brain, Quinn explained.

So the new study, "would suggest that intervening in a drug-like way does not work," MacKay said. "What they really need to look at is whether fish consumption or supplementation with omega-3 oils throughout adulthood reduces the risk for developing Alzheimer's," he noted.

For this study, about 400 men and women, average age 76, were randomized to receive 2 grams daily of DHA or a placebo. All had mild to moderate Alzheimer's, meaning "they had enough of an impairment to justify a diagnosis but are living at home, interacting with families and enjoying a pretty good quality of life," Quinn said. "These are people for whom slowing the rate of progression would really make a difference."

Participants weren't eating a lot of fish or taking supplements at the start of the study.

Although both blood and cerebrospinal fluid levels of DHA increased in the treatment group, there were no differences on two different measures of cognitive function between the groups, Quinn reported.

The only slightly encouraging news was that people without the APOE-4 gene variant, which confers a higher risk of Alzheimer's, may have benefited slightly. However, Quinn urged extreme caution in interpreting this secondary analysis.

"It's not so solid a finding that it should change any treatment recommendations or advice to the public," he said.

A second study appearing in the same journal and presented at the news conference found that being hospitalized or having activity restricted as the result of illness or injury, as well as general physical frailty, speeded an elderly person becoming disabled or more disabled and even dying.

Not surprisingly, falls were at particular fault.

Only 117 participants were still nondisabled and alive at the end of the study, which involved almost 800 elderly adults and lasted a decade. An illness or injury leading to hospitalization increased the likelihood of shifting from not disabled to severely disabled more than 160-fold, said study author Dr. Thomas Gill, a professor of medicine at Yale School of Medicine in New Haven, Conn., where the research was conducted.

More information

The Alzheimer's Association has ways to maintain your brain.

Vitamin B puts off Alzheimer's

A new study suggests high doses of B vitamins may halve the rate of brain shrinkage in older people experiencing some of the warning signs of Alzheimer's disease.

Brain shrinkage is one of the symptoms of mild cognitive impairment, which often leads to dementia.
Researchers say this could be the first step towards finding a way to delay the onset of Alzheimer's.
Experts said the findings were important but more research was needed.

The study, published in the journal Public Library of Science One, looked at 168 elderly people experiencing levels of mental decline known as mild cognitive impairment.
This condition, marked by mild memory lapses and language problems, is beyond what can be explained by normal ageing and can be a precursor to Alzheimer's and other forms of dementia.

Half of the volunteers were given a daily tablet containing levels of the B vitamins folate, B6 and B12 well above the recommended daily amount. The other half were given a placebo.

After two years, the rate at which their brains had shrunk was measured.
The average brain shrinks at a rate of 0.5% a year after the age of 60. The brains of those with mild cognitive impairment shrink twice as fast. Alzheimer's patients have brain shrinkage of 2.5% a year.
The team, from the Oxford Project to investigate Memory and Ageing (Optima), found that on average, in those taking vitamin supplements, brain shrinkage slowed by 30%.
In some cases it slowed by more than 50%, making their brain atrophy no worse than that of people without cognitive impairment.

'Protecting' the brain
Certain B vitamins - folic acid, vitamin B6 and B12 - control levels of a substance known as homocysteine in the blood. High levels of homocysteine are associated with faster brain shrinkage and Alzheimer's disease.

The study authors believe it was the B vitamins' effect on levels of homocysteine that helped slow the rate of brain shrinkage.

The study author, Professor David Smith, said the results were more significant than he had expected.
"It's a bigger effect than anyone could have predicted," he said, "and it's telling us something biological.
"These vitamins are doing something to the brain structure - they're protecting it, and that's very important because we need to protect the brain to prevent Alzheimer's."

He said more research was now needed to see whether high doses of B vitamins actually prevented the development of Alzheimer's in people with mild cognitive impairment.
The Alzheimer's Research Trust, which co-funded the study, also called for further investigation.
"These are very important results, with B vitamins now showing a prospect of protecting some people from Alzheimer's in old age," said chief executive Rebecca Wood.

"The strong findings must inspire an expanded trial to follow people expected to develop Alzheimer's."
B vitamins are found naturally in many foods, including meat, fish, eggs and green vegetables.
Experts are warning people not to start taking very high levels of vitamin supplements without medical advice.

Chris Kennard, chair of the Medical Research Council's Neurosciences and Mental Health Board, said: "We must be cautious when recommending supplements like vitamin B as there are separate health risks if taken in too high doses.

"Further research is required before we can recommend the supplement as a treatment for neurodegenerative diseases, such as Alzheimer's."

The UK's Food Standards Agency says taking more than 200 milligrams a day of vitamin B6 can lead to a loss of feeling in the arms and legs, but these symptoms are reversible once someone stops taking the supplements.

It adds that taking 2mg or less of vitamin B12 supplements a day is unlikely to cause harm, but that there is not enough evidence to know what the effects of taking more than that would be.
Taking too much folic acid - over 1mg a day - can mask signs of vitamin B12 deficiency. An early symptom of B12 deficiency is anaemia, but taking large amounts of folic acid treats the anaemia without treating the B12 deficiency.
from http://www.bbc.co.uk/news/health-11232356

Sniffing insulin may help memory lost to Alzheimer's

(Reuters) - Squirting insulin up the noses of patients with early forms of Alzheimer's disease showed signs of improving their memory, U.S. researchers said on Wednesday.

Patients who got the treatment for four months showed improvements in tests of memory recall that lasted for two months.

"We believe our results are very promising and they warrant future trials," said Dr. Suzanne Craft of the VA Puget Sound Health Care System and the University of Washington in Seattle, who presented her findings at a meeting of the Alzheimer's Association in Honolulu.

Alzheimer's disease is a fatal and incurable deterioration of the brain that affects 26 million people globally. It is the most common form of dementia.

Several studies have suggested that people with Alzheimer's have reduced levels of insulin in the brain, even in the earliest stages. Insulin is important for communication between brain cells and is needed for brain function.

Craft's team wanted to see what would happen if they delivered insulin directly to the brain.

They studied 109 non-diabetic patients with Alzheimer's disease or a precursor condition called mild cognitive impairment.

A third of the patients got a placebo and the other two-thirds received different doses of insulin that had been loaded into a nebulizer and squirted up their nose twice daily for four months.

Patients who got the lower dose of insulin showed significant improvements in some tests of memory, but they showed no change in a test of memory and learning or in a test of their ability to do daily activities.

In 15 insulin-treated patients who agreed to a spinal tap, the team found a link between improved memory and improvements in measurements of key proteins linked with Alzheimer's disease.

Craft said the treatment is a long way from being useful to patients, but the findings are strong enough to be studied in a large clinical trial.

Current Alzheimer's drugs only treat symptoms, but so far no drugs have been shown to improve memory in patients with Alzheimer's.

University of Miami Researchers ID Alzheimer's Risk Gene

University of Miami researchers have identified a gene that appears to double a person's risk of developing late-onset Alzheimer's disease.

They called the finding a small step toward understanding and fighting the debilitating disease, which affects five million Americans. "I hope that in the next five to 10 years we can see major improvements -- a combination of therapies and prevention through exercise, both physical and mental, diet and other things," said Margaret Pericak-Vance. She is director of the John P. Hussman Institute for Human Genomics at the UM Medical School and principal investigator in the study.

From past studies, researchers knew that people with high levels of the amino acid homocysteine in their blood are more likely to develop Alzheimer's, Pericak-Vance said. The new information gives scientists a cause-and-effect, because the gene just discovered is known to influence the body's levels of homocysteine, she said. [Source: Miami Herald]

Danone works on anti- Alzheimer's drink

Functional and health food manufacturer Danone could launch a new milkshake product which will improve the lives of Alzheimer's sufferers if large scale trials prove successful.

The company, which is probably best known for its Actimel and Activia brands, designed and financed the research which was undertaken by doctors and the world-renowned Massachusetts Institute of Technology(MIT) in the US.

Danone's signature brands claim to have benefits such as improving digestive transit and increasing the body's defences.

Over 200 people who were suffering from mild Alzheimer's disease took part in the test which involved half drinking a cocktail of three special nutrients and the other half drinking a placebo. The two groups were given a memory test at the beginning and end of the experiment and after 12 weeks 40 per cent of the group recorded improved test results.

Researcher Professor Richard Wurtman told the Daily Mail: "This is something that has no toxicity that gives you better function than you started with. If it works in the follow-up studies, it is very exciting."

However, the MIT researchers warned that results from the larger tests could be less successful than those experienced by the small sample.