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New research has found that low vitamin D levels among older adults is associated with accelerated cognitive decline and impaired performance (particularly in areas of memory and executive function). The next research in this area will have to look at whether vitamin D supplementation will change (slow down) the decline. Please note that it is widely accepted that an average daily intake of 1000 IU  of D3 daily is safe. The best source of  vitamin D is sunlight. From Science Daily:

Low vitamin D among elderly associated with decline in cognition, dementia

Vitamin D insufficiency among the elderly is highly correlated with accelerated cognitive decline and impaired performance, particularly in domains such as memory loss that are associated with Alzheimer's disease and dementia, researchers with the UC Davis Alzheimer's Disease Center and Rutgers University have found. The effect is "substantial," with individuals with low vitamin D declining at a rate three times faster than those with adequate vitamin D levels

The researchers said their findings amplify the importance of identifying vitamin D insufficiency among the elderly, particularly high-risk groups such as African-Americans and Hispanics, who are less able to absorb the nutrient from its most plentiful source: sunshine. Among those groups and other darker-skinned individuals, low vitamin D should be considered a risk factor for dementia, they said. "Independent of race or ethnicity, baseline cognitive abilities and a host of other risk factors, vitamin D insufficiency was associated with significantly faster declines in both episodic memory and executive function performance," said Joshua Miller...

The large, longitudinal study was conducted in nearly 400 racially and ethnically diverse men and women in Northern California participating in longitudinal research at the Alzheimer's Disease Center in Sacramento, Calif. Fifty percent of participants were Caucasian and 50 percent were African-American or Hispanic. The participants had a mean age of 76 and were either cognitively normal, had mild cognitive impairment, or dementia.The participants' serum vitamin D status was measured at the beginning of the study.... Overall, 26 percent were deficient and 35 percent were insufficient. Among Caucasians, 54 percent had low vitamin D, compared with 70 percent of African-Americans and Hispanics.

Over five years of follow-up, vitamin D deficient individuals experienced cognitive declines that were two-to-three times faster than those with adequate serum vitamin D levels. In other words it took only two years for the deficient individuals to decline as much as their counterparts with adequate Vitamin D declined during the five-year follow-up period.

Exposing the skin to sunlight is the major source of vitamin D. Racial and some ethnic minorities are at greater risk of low vitamin D because the higher concentration of melanin that makes their skin darker -- and protects against skin cancer in sunny climates -- also inhibits synthesis of vitamin D. Diet is the other major source of vitamin D. Dietary vitamin D is obtained particularly through dairy consumption. The intake of dairy products is especially low among minority groups, with only 6.5 percent of African-Americans and 11 percent of Mexican-Americans nationwide consuming the recommended three daily servings of dairy products, the study says.

Image result for dark chocolate So far all the studies I've seen in the past 2 years about cocoa and chocolate have found various beneficial health effects from regularly eating small amounts of cocoa and chocolate. Now 2 new studies found benefits from the flavanols found in cocoa beans and chocolate. The studies found that consuming cocoa flavanols lowers blood pressure, increases flow-mediated vasodilation,improves blood cholesterol profile, and that regular dietary intake may reduce the risk of cardiovascular disease (CVD). However, note that chocolate and cocoa contain other compounds besides flavanols and these may also be exerting positive effects.

So now the question becomes, which chocolates have high levels of flavanols? Modern processing removes some of the flavanols - in fact, the more it undergoes processing, the more flavanols are lost. But it appears that dark chocolate and cocoa that has not undergone Dutch processing is best. According to a Medscape article on cocoa flavanols: "Traditional processing methods that yield "modern chocolate," especially alkalinization (dutching or Dutch processing, to mellow flavor), strips flavanols from cocoa. The bitterness from cacao mostly comes from flavanols. With the emerging recognition of the beneficial effects of flavanols there has been a shift in commercial production towards chocolate forms with high flavanol content." A recent study by Consumer Lab, which compared flavanol levels across many cocoa and chocolate products, also found that some chocolate brands were contaminated with cadmium (a toxic heavy metal), but that cocoa nibs had significantly lower levels. At any rate, the medical evidence does not support gorging on chocolate, but instead consuming chocolate or cocoa in moderation. From Science Daily:

Cocoa flavanols lower blood pressure and increase blood vessel function in healthy people

Two recently published studies in the journals Age and the British Journal of Nutrition (BJN) demonstrate that consuming cocoa flavanols improves cardiovascular function and lessens the burden on the heart that comes with the aging and stiffening of arteries. The studies also provide novel data to indicate that intake of cocoa flavanols reduces the risk of developing cardiovascular disease (CVD).

As we age, our blood vessels become less flexible and less able to expand to let blood flow and circulate normally, and the risk of hypertension also increases. Arterial stiffness and blood vessel dysfunction are linked with cardiovascular disease -- the number one cause of deaths worldwide....Cocoa flavanols are plant-derived bioactives from the cacao bean. Dietary intake of flavanols has been shown to have a beneficial effect on cardiovascular health but the compounds are often destroyed during normal food processing. Earlier studies have demonstrated that cocoa flavanol intake improves the elasticity of blood vessels and lowers blood pressure....These two studies in Age and BJN are the first to look at the different effects dietary cocoa flavanols can have on the blood vessels of healthy, low-risk individuals with no signs or symptoms of cardiovascular disease.

Cocoa flavanols increase blood vessel flexibility and lower blood pressure - In the study published in Age, two groups of 22 young (<35 years of age) and 20 older (50-80 years of age) healthy men consumed either a flavanol-containing drink, or a flavanol-free control drink, twice a day for two weeks. The researchers then measured the effect of flavanols on hallmarks of cardiovascular aging, such as arterial stiffness (as measured by pulse wave velocity), blood pressure and flow-mediated vasodilation (the extent to which blood vessels dilate in response to nitric oxide). They found that vasodilation was significantly improved in both age groups that consumed flavanols over the course of the study (by 33% in the younger age group and 32% in the older age group over the control intervention). In the older age group, a statistically and clinically significant decrease in systolic blood pressure of 4 mm Hg over control was also seen.

Improving cardiovascular health and lowering the risk of CVD - In the second study, published in BJN, the researchers extended their investigations to a larger group (100) of healthy middle-aged men and women (35-60 years) with low risk of CVD. The participants were randomly and blindly assigned into groups that consumed either a flavanol-containing drink or a flavanol-free control drink, twice a day for four weeks.

"We found that intake of flavanols significantly improves several of the hallmarks of cardiovascular health," says Professor Kelm. In particular, the researchers found that consuming flavanols for four weeks significantly increased flow-mediated vasodilation by 21%. Increased flow-mediated vasodilation is a sign of improved endothelial function and has been shown by some studies to be associated with decreased risk of developing CVD. In addition, taking flavanols decreased blood pressure (systolic by 4.4 mmHg, diastolic by 3.9 mmHg), and improved the blood cholesterol profile by decreasing total cholesterol (by 0.2 mmol/L), decreasing LDL cholesterol (by 0.17 mmol/L), and increasing HDL cholesterol (by 0.1 mmol/L).

The researchers also calculated the Framingham Risk Score -- a widely used model to estimate the 10-year cardiovascular risk of an individual -- and found that flavanol intake reduced the risk of CVD. "Our results indicate that dietary flavanol intake reduces the 10-year risk of being diagnosed with CVD by 22% and the 10-year risk of suffering a heart attack by 31%," says Professor Kelm.

The combined results of these studies demonstrate that flavanols are effective at mitigating age-related changes in blood vessels, and could thereby reduce the risk of CVD in healthy individuals. The application of 10-year Framingham Risk Scores should be interpreted with caution as the duration of the BJN study was weeks not years and the number of participants was around 100, not reaching the scale of the Framingham studies. That being said, Professor Kelm comments that "the reduction seen in risk scores suggests that flavanols may have primary preventive potential for CVD."

The following article posted average life expectancies for both men and women in countries throughout the world. But what was interesting is that it also gave the average years that a person would be healthy and also unhealthy (which is typically the last years of life). And no matter which country one looks at and the average life expectancy of men and women, it turns out that on average people spend about one eighth of their life in a disabled or unhealthy state. Or between 10 to 20% of their life disabled or unhealthy.

So looking at the United States, it is expected that the average women will live 81 years, but about 13 of those years will be in poor health. Men in the USA will live on average 76 years, but of that about 11 years will be unhealthy. Which means, don't wait until retirement to travel and do all those things you want to do, because you may have health issues preventing you from doing those things - so get out there NOW and DO IT ALL. The "bucket list" should be started now. (Note: I only copied information for 5 countries, but the actual chart has 188 countries. Do go check it out.) From NPR News:

Check Out Life Spans Around The World — And Likely Years Of Ill Health

How Long Will You Live — And How Many Of Those Years Will Be Healthy?

Here are the life expectancies in 188 countries — and the number of unhealthy years a person faces. No matter where you live, the range for years of healthy life is 80 to 90 percent.

Life expectancy compared with global average:

COUNTRY       MALE    UNHEALTHY YEARS       FEMALE       UNHEALTHY YEARS

GLOBAL            68                  8                                     74                       10

CANADA           79                 10                                     83                       12

CHINA               73                   8                                     79                         9

MEXICO             72                  9                                      78                       11

RUSSIA               65                 7                                       76                       10

USA                    76                 11                                      81                       13


Credit: Christopher Groskopf and Alyson Hurt/NPR  
   Notes: — Life expectancies are estimated for individuals born in 2013.  

It's one of those good news/bad news stories. A study in the medical journal The Lancet found that people around the world — in countries rich, poor and in the middle — are living longer. But here's the rub. You can't count on living those extra years in good health.

In the first of what will be an annual look at health along with life span around the world called the Global Burden of Disease Study, researchers found that between 1990 and 2013, life expectancy rose by 6.2 years. The average life span at birth across the globe is now 71.5 years, though rates vary tremendously by region. People live the longest, according to the Lancet study, in Andorra, in southwestern Europe, or an average of 83.9 years. People die the youngest, an average of 48.3 years, in Lesotho, in Africa.

But regardless of socioeconomics, geography or total number of years lived, the study shows what appears to be a universal part of the human condition: people live an average of one-eighth of their lives in a disabled or unhealthy state.

"What's interesting is that wherever you go around the world, about seven-eighths of life expectancy is healthy," says Peter Byass, professor of global health at UmeaUniversity in Sweden. "I'm not sure we totally understand why.We probably can't do a lot about decreasing this part of life that's not healthy," he adds. "That pretty much appears to be a part of being human."

Healthy life — the measure researchers used, called HALE, or healthy life expectancy years — ranged from a high of 73.4 years in Japan to a low, again in Lesotho, of 42 years. Not much is known about when those years of ill health occur. "A lot of the unhealthy stuff is around end of life," says Byass.

Spending more money on health care doesn't seem to reduce the proportion of life spent in ill health. The study was based on regional data and showed that in high-income North America, men live an average of 76.64 years, but only 66.17 of those years are healthy; women live an average of 81.62 years, but experience good health in only 68.85 of those years. The United States, which spends more on health care than any other country, is part of that high-income region. "This is seen even in places where there's a high investment in health care," says Byass, who wrote a commentary accompanying the Lancet study.

Countries where people die the youngest have the highest rates of communicable diseases like AIDS, malaria and tuberculosis as well as high rates of maternal and childhood mortality and malnutrition. "If we want to have a healthier global population, more equal health, the world has got to invest in getting rid of those avoidable problems in poorer countries, mainly in Africa," says Byass.

Again, more benefits of vitamin D. Think of it as the sunshine vitamin, but supplements also work, especially vitamin D3 (rather than D2). This time higher levels of vitamin D in the blood (as measured by the vitamin D biomarker, 25-hydroxyvitamin D [25(OH)D) are linked to lower incidence of macular degeneration among those women genetically prone to it.

Macular degeneration is thought to have both genetic (inherited) and environmental components. Currently macular degeneration is the leading cause of vision loss and affects about 2.07 million Americans (this is according to the National Eye Institute). Note that this number is very different than that given by the American Macular Degeneration Foundation in the article. From Medical Xpress:

Vitamin D may play key role in preventing macular degeneration

Vitamin D has been studied extensively in relation to bone health as well as cancer. Now, a team led by a researcher at the University at Buffalo has discovered that vitamin D may play a significant role in eye health, specifically in the possible prevention of age-related macular degeneration, or AMD, among women who are more genetically prone to developing the sight-damaging disease.

In a paper published today (Aug. 27) in JAMA Ophthalmology online, Amy Millen, associate professor of epidemiology and environmental health in UB's School of Public Health and Health Professions, and her team found that women who are deficient in vitamin D and have a specific high-risk genotype are 6.7 times more likely to develop AMD than women with sufficient vitamin D status and no high risk genotype.

Macular degeneration is characterized by the deterioration of the macula, a small part of the central retina where the eye's photoreceptors (rods and cones) are most highly concentrated. The leading cause of legal blindness, macular degeneration affects more than 10 million Americans—more than cataracts and glaucoma combined—according to the American Macular Degeneration Foundation. The disease affects a person's central vision, which is needed for common tasks such as reading and driving. The effect is similar to that of a rain drop on the center of a camera lens.

Researchers analyzed data compiled on 1,230 women ages 54 to 74 who participated in the Carotenoids in Age-related Eye Disease Study (CAREDS),..... CAREDS was conducted among participants at three of the centers: University of Wisconsin (Madison), the University of Iowa (Iowa City) and the Kaiser Center for Health Research (Portland, Oregon). Researchers were able to determine participants' vitamin D status by analyzing serum samples for a vitamin D biomarker, 25-hydroxyvitamin D [25(OH)D], which provided a glimpse into vitamin D intake through all sources: diet, supplements and sunlight.

Human skin can synthesize vitamin D when exposed to ultraviolet light, Millen explains. However, for many people, 15 to 30 minutes a day with 10 percent of their skin exposed might be sufficient. In winter months, when there is a lower solar angle, sun exposure may not be not sufficient to maintain blood level for people who live north of a line from about Washington, D.C., to Los Angeles. At these times and locations, dietary intake may be needed. Dietary sources of vitamin D include fortified foods such as milk and foods that naturally contain vitamin D such as fatty fish like salmon and mackerel.

"Macular degeneration has been found to be strongly associated with genetic risk," Millen says. Among many genes linked to AMD, one of the strongest is a specific genetic variant (Y402H) in the complement factor H gene, called CFH for short. This gene codes for the CFH protein that is involved in the body's immune response to destroy bacteria and viruses. Inflammation is believed to be involved in the development of macular degeneration.  "People who have early stage AMD develop drusen, lipid and protein deposits that build up in the eye. Your body sees this drusen as a foreign substance and attacks it, in part via the complement cascade response," explains Millen.

Vitamin D shows promise for protecting against because of its anti-inflammatory and antiangiogenic properties; antiangiogenic refers to slowing the growth of new blood vessels, often seen in late stages of AMD."Our message is not that achieving really high levels of vitamin D are good for the eye, but that having deficient vitamin D levels may be unhealthy for your eyes," Millen says. 

Although the odds of having AMD was higher in women who were deficient for vitamin D, with 25(OH)D levels below 12 ng/mL (30 nmol/L), increasing vitamin D levels beyond 12 ng/mL did not further lower the odds of AMD to any meaningful extent, she explains.

 Artificial trans fats in foods are bad for health in so many ways: linked to increased risk of coronary heart disease, atherosclerosis, inflammation, and risk of early death. And even though the FDA is finally phasing out partially hydrogenated oils (because they have high levels of artificial trans fats) within the next 3 years, trans fats will still be found in foods (processed foods). How can this be? Well, trans fats are still allowed to be in foods that are labeled as 0 trans fats if it is less than .5 grams trans fats per serving (a loophole allows them to round downward to zero ). And according to research by Environmental Working Group (EWG), trans fats are being used by the food industry in undisclosed ways in amounts low enough to exploit the trans fat loophole. Besides partially hydrogenated oils, they are found in other types of refined oils, monoglycerides, diglycerides and other emulsifiers, and even in flavors and colors. So when you see ZERO trans fats on the label, it doesn't actually mean that it is zero trans fats. The problem is that over the course of a day, eating a number of foods and servings that have under .5 grams of trans fats adds up to levels that research now says has negative health effects!

Artificial trans fats are found in a lot of processed foods. A EWG analysis found that harmful artificial trans fatty acids lurk in more than 27 percent of more than 84,000 processed foods common in American supermarkets.  Another 10 percent contain ingredients likely to contain trans fat. Foods most likely to have hidden trans fats are: breakfast bars, granola and trail mix bars, pretzels, peanut butter, crackers, breads, kids fruit snacks, kids cereal, graham crackers, whipped topping, non-dairy creamers, pudding mixes, cupcakes, and ice cream cones.

So what can you do? Read ingredient lists on labels and try to avoid foods with the above mentioned ingredients: partially hydrogenated oils, emulsifiers, monoglycerides, diglycerides and other emulsifiers, artificial flavors, artificial flavors, and colors. Try to cut back or avoid foods that have ingredients that are not real foods - tough to do, but it can be done.

And the amazing part, saturated fats (such as butter) are NOT linked to early death and heart disease, but trans fat in foods is. Latest research, from Science Daily:

Trans fats, but not saturated fats like butter, linked to greater risk of early death and heart disease

A study led by researchers at McMaster University has found that that trans fats are associated with greater risk of death and coronary heart disease, but saturated fats are not associated with an increased risk of death, heart disease, stroke, or Type 2 diabetes. The findings were published today by the British Medical Journal (BMJ)...."For years everyone has been advised to cut out fats. Trans fats have no health benefits and pose a significant risk for heart disease, but the case for saturated fat is less clear," said de Souza.

Saturated fats come mainly from animal products, such as butter, cows' milk, meat, salmon and egg yolks, and some plant products such as chocolate and palm oils. Trans unsaturated fats (trans fats) are mainly produced industrially from plant oils (a process known as hydrogenation) for use in margarine, snack foods and packaged baked goods.

Contrary to prevailing dietary advice, a recent evidence review found no excess cardiovascular risk associated with intake of saturated fat. In contrast, research suggests that industrial trans fats may increase the risk of coronary heart disease.

To help clarify these controversies, de Souza and colleagues analysed the results of 50 observational studies assessing the association between saturated and/or trans fats and health outcomes in adults....The team found no clear association between higher intake of saturated fats and death for any reason, coronary heart disease (CHD), cardiovascular disease (CVD), ischemic stroke or type 2 diabetes. However, consumption of industrial trans fats was associated with a 34 per cent increase in death for any reason, a 28 per cent increased risk of CHD mortality, and a 21 per cent increase in the risk of CHD.

Inconsistencies in the studies analysed meant that the researchers could not confirm an association between trans fats and type 2 diabetes. And, they found no clear association between trans fats and ischemic stroke. The researchers stress that their results are based on observational studies, so no definitive conclusions can be drawn about cause and effect.

Another study finds health benefits to eating a Mediterranean based diet (here combined with the DASH diet) - the MIND diet. The researchers found that the older adults who followed the diet best were about 7.5 years younger cognitively than those who followed it least, thus suggesting that it may slow the cognitive decline of aging. Earlier research had suggested that it may reduce a person's risk in developing Alzheimer's disease. Foods to eat: fruits, vegetables, berries, whole grains, legumes (beans), nuts, fish, a little wine, and some chicken. Foods to limit on this diet: butter, red meat, margarine, sweets and pastries, whole fat cheese, and fried or fast food. From Medical Xpress:

Eating away at cognitive decline: MIND diet may slow brain from aging by 7.5 years

While cognitive abilities naturally diminish as part of the normal aging process, it may be possible to take a bite out of this expected decline. Eating a group of specific foods known as the MIND diet may slow cognitive decline among aging adults, even when the person is not at risk of developing Alzheimer's disease, according to researchers at Rush University Medical Center. This finding is in addition to a previous study by the research team that found that the MIND diet may reduce a person's risk in developing Alzheimer's disease.

The recent study shows that older adults who followed the MIND diet more rigorously showed an equivalent of being 7.5 years younger cognitively than those who followed the diet least. The results of the study recently were published online in the journal Alzheimer's & Dementia: The Journal of the Alzheimer's Association.

The National Institute of Aging funded study evaluated cognitive change over a period of 4.7 years among 960 older adults who were free of dementia on enrollment. Averaging 81.4 years in age....residents of more than 40 retirement communities and senior public housing units in the Chicago area. .... Martha Clare Morris, ScD, a nutritional epidemiologist, and colleagues developed the diet, whose full name is the Mediterranean-DASH Diet Intervention for Neurodegenerative Delay. As the name suggests, the MIND diet is a hybrid of the Mediterranean and DASH (Dietary Approaches to Stop Hypertension) diets. Both diets have been found to reduce the risk of cardiovascular conditions, like hypertension, heart attack and stroke.

"Everyone experiences decline with aging; and Alzheimer's disease is now the sixth leading cause of death in the U.S., which accounts for 60 to 80 percent of dementia cases. Therefore, prevention of cognitive decline, the defining feature of dementia, is now more important than ever," Morris says.

The MIND diet has 15 dietary components, including 10 "brain-healthy food groups" and five unhealthy groups - red meat, butter and stick margarine, cheese, pastries and sweets, and fried or fast food. To adhere to and benefit from the MIND diet, a person would need to eat at least three servings of whole grains, a green leafy vegetable and one other vegetable every day—along with a glass of wine—snack most days on nuts, have beans every other day or so, eat poultry and berries at least twice a week and fish at least once a week. In addition, the study found that to have a real shot at avoiding the devastating effects of cognitive decline, he or she must limit intake of the designated unhealthy foods, especially butter (less than 1 tablespoon a day), sweets and pastries, whole fat cheese, and fried or fast food (less than a serving a week for any of the three).

Berries are the only fruit specifically to be included in the MIND diet. "Blueberries are one of the more potent foods in terms of protecting the brain," Morris says, and strawberries also have performed well in past studies of the effect of food on cognitive function.

An observational study of older adults found that the Mediterranean diet may help preserve the connections between neurons in the brain, by preserving the microstructure in the white matter of the brain. This appeared to have a strong cognitive benefit - equal up to 10 years of delayed cognitive aging in those who adhered to the Mediterranean diet most closely. So if you haven't started already, try eating what the Mediterranean diet stresses: fruits, vegetables, whole grains, seeds, nuts, legumes, olive oil, some fish, and some wine. And cut back on highly processed foods, meat, and high fat foods. It's not one or two foods, but overall diet that is important. From Medscape:

Mediterranean Diet May Preserve Brain Structural Connectivity

The Mediterranean diet may help preserve structural connectivity in the brain in older adults, results of a French study hint. Greater adherence to the Mediterranean diet was associated with preserved microstructure in extensive areas of the white matter up to a decade later, the study team found. And this appeared to be related to strong cognitive benefit, equal to up to 10 years of delayed cognitive aging for those with the greatest adherence, they say....The study was published online July 16 in Alzheimer's & Dementia. The Mediterranean diet has been associated with a lower risk for Alzheimer's disease, but the underlying mechanisms have been unclear.

The new findings are based on 146 nondemented older adults in the Bordeaux Three-City study, a prospective cohort initiated in 1999-2000 to study vascular risk factors for dementia. Participants provided information on their diet in 2001-2002 (at a mean age of 73 years), underwent brain MRI an average of 9 years later (including diffusion tensor imaging)...On the basis of dietary assessment, 26% of participants had a low Mediterranean diet (MedDi) score of 0 to 3, indicating poor adherence to the diet; 47% had medium scores (4 or 5); and 27% had higher scores (6 to 8) representing the best adherence to the diet.

In adjusted analysis, there was no significant association between the MedDi score and grey matter or white matter volume. However, there was a strong association between the MedDi and diffusion tensor imaging patterns, suggesting that higher MeDi adherence was associated with a "general pattern of preserved WM [white matter] microstructure in multiple bundles," the researchers say. And preserved white matter microstructure with higher adherence to the MedDi "appeared to delay cognitive aging by up to 10 years."

"Our results suggest that the Mediterranean diet helps preserve the connections between neurons, which appear to be damaged with aging, vascular brain diseases and neurodegenerative diseases such as Alzheimer's dementia," Dr Samieri told Medscape Medical News. "In addition, the regions which appeared preserved with greater adherence to the Mediterranean diet were extended and were not specific to a particular disease, suggesting that the Mediterranean diet may have the potential to prevent not only stroke (as previously demonstrated with the PREDIMED [Prevención con Dieta Mediterránea] trial) but also multiple age-related brain pathologies," she added.

The added finding that none of the individual components of the Mediterranean diet was strongly associated with imaging results "supports our hypothesis that overall diet quality may be more important to preserve brain structure than any single food," they write.

Several recent studies found that air pollution has a negative effect on the brain. This study of elderly women in North Carolina found that long-term exposure to higher levels of air pollution (specifically fine particulate matter smaller than 2.5 micrometers (called PM2.5) resulted in smaller brain volumes (especially the brain's white matter). They studied elderly women (aged 71 to 89), but the findings should be of concern to everyone exposed to high levels of air pollution.  White matter connects brain regions (with nerve fibers that pass signals throughout the brain) and determines how information is processed in the brain. The researchers pointed out that other recent studies reported that high air pollution is linked to cognitive decline and accelerated brain aging. From Futurity:

AIR POLLUTION MAY SHRINK BRAIN’S WHITE MATTER

Exposure to air pollution may have a negative impact on how the brain’s white matter ages. Older women who lived in geographic locations with higher levels of fine particulate matter in ambient air had significantly smaller white matter volumes across a wide range of brain areas, new research shows.

Fine particulate matter is smaller than 2.5 micrometers and is known as PM2.5, a form of pollution that easily enters the lungs and possibly the bloodstream. White matter connects brain regions and determines how information is processed in the brain....“Our study provides convincing evidence that several parts of the aging brain, especially the white matter, are an important target of neurotoxic effects induced by long-term exposure to fine particles in the air.”

The study found that older women ages 71 to 89 who had lived in places with greater PM2.5 exposures had significantly smaller volumes of white matter and that this could not be explained by the geographic region where they lived, their race or ethnic background, socioeconomic status, lifestyle, or medical conditions that may also influence brain volumes.

The researchers performed brain magnetic resonance imaging scans of 1,403 women who are part of the Women’s Health Initiative Memory Study (WHIMS), a nationwide report based at Wake Forest Baptist Medical Center in Winston-Salem, NC. The researchers also used residential histories and air monitoring data to estimate the participants’ exposure to air pollution in the previous six to seven years.

White matter contains nerve fibers and connects brain regions with each other by traveling deep within and passing nerve signals throughout the brain. Gray matter is primarily composed of neuronal cell bodies, dendrites, glial cells, and capillaries. The study did not find impacts from exposure to air pollution in participants’ gray matter.

People fear dementia and Alzheimer's disease, because they are progressive diseases that nothing treats successfully. However, in the past year there have been some studies showing improvements with lifestyle changes (not cures, but for some the progression was slowed or showing some improvements).

The latest studies found that exercise (especially aerobic execise) had some beneficial effects on those with mild cognitive impairment (MCI), Alzheimer's disease, and vascular cognitive  impairment (VCI): neuropsychiatric improvements, improvements in biomarkers for the disease, and improved blood flow to the brain. From Medscape:

Physical Activity May Help Treat Dementia

New research shows that being physically active not only reduces cognitive decline and improves neuropsychiatric symptoms in patients with dementia but may actually reduce Alzheimer's disease (AD) biomarkers, including amyloid and tau protein in the brain. Exercise could also benefit patients with types of dementia other than AD, another study suggests.Some of this promising new research on exercise was presented at the Alzheimer's Association International Conference (AAIC) 2015. 

Danish researchers had already presented cognition-related results of the multicenter ADEX study ...The intervention consisted of 1 hour of aerobic exercise three times a week for 16 weeks. The control group received usual care..... The analysis found that these [neuropsychiatric] symptoms improved in the 66 patients in the "high exercise"group... The NI is a 12-item questionnaire that rates, among other things, depression, apathy, agitation, hallucinations, irritability, weight loss, and sleep."We saw that the control group got worse; there was a small decline in this group, which you would expect because this is progressive disease," said Steen Hasselbalch, MD, Danish Dementia Research Centre, Copenhagen, Denmark. "But the intervention group remained at the same level and even got a little better, so at end of the intervention there was a significant difference."

The question arises of whether exercise could not just delay worsening of symptoms but actually change brain pathology.The answer, suggests other research, is yes. In a separate study presented at the AAIC 2015, researchers found decreased phosphorylated tau (P tau) in older, previously sedentary persons completing a 6-month regimen of moderate- to high-intensity aerobic exercise.

The study enrolled 70 patients aged 55 to 89 years with prediabetes as well as amnestic mild cognitive impairment (MCI)....We think they are at high, high risk for developing dementia of the Alzheimer's type." These patients were randomly assigned to the aerobic exercise group or to the stretching group. Those in the aerobic group started slowly — 10 minutes of exercise a week — and gradually built the time and intensity up over 6 weeks to the point where they were exercising 45 minutes a day, 4 days a week, at 75% to 85% of their maximum heart rate...."This group had a choice of exercises: treadmill, stationary cycling, elliptical trainer, or preapproved group classes.

The stretching group, whose members could do balance exercises, gentle yoga, and other approved classes in addition to stretching, maintained a maximum heart rate of below 35%. All exercises were adapted to the needs and limitations of individual patients and were done at a local YMCA.

The researchers looked at biomarkers in cerebrospinal fluid (CSF), including P tau protein and amyloid β 42....Most intervention trials don't show such changes in P tau. "But we saw it with exercise and no medications," said Dr. Baker. "Exercise was enough to move a biomarker that indicates the severity of the disease."  It wasn't surprising, she added, that this was true only for older patients. "It may be that before age 70, you have a lot of compensatory mechanisms that help to maintain brain health, and after 70, those start breaking down."

The study also showed that the aerobic activity increased blood flow to the brain...The researchers demonstrated that the increased blood flow was in regions characteristically affected by aging and AD (ie, memory and processing)Cognitive benefits were particularly noteworthy for executive function..."Our brain imaging results are just fantastic; they show some really nice increases in blood flow in the areas of brain that support executive function and areas of the brain that normally show decreased flow for people with MCI, so it's reversing the blood flow detriment in MCI."

AD may not be the only dementia potentially treatable through exercise. Another study discussed at the meeting showed that this intervention may help those with vascular cognitive impairment (VCI)It's the first intervention trial to suggest that exercise can improve cognition in patients with confirmed VCI, said Teresa Liu- Ambrose, PhD, Canada Research Chair, University of British Columbia, Vancouver, Canada, who reported the results.The 6-month study included 71 patients aged 56 to 96 years with mild VCI of varying physical capacities. They were assigned to usual care that included a nutrition component or to an intervention of moderate-intensity walking, 3 times a week for an hour....In a subset of patients who had neuroimaging, there was "evidence of efficiency" in the brain of those who exercised, Dr Liu-Ambrose told Medscape Medical News.

Recently I've seen a number of published studies that found benefits to someone being bilingual or benefits in learning a new language. Some benefits recently found in bilinguals (or the "billngual advantage"): more gray matter in the executive control area of the brain, 4 to 5 year delay in onset of Alzheimer's symptoms, processing of information more efficiently and more easily, and young bilingual children are more likely to think that everything is learned (while monolinguals more likely to think things are innate). From Science Daily:

Bilinguals of two spoken languages have more gray matter than monolinguals

A new study published in the journal Cerebral Cortex suggests people who speak two languages have more gray matter in the executive control region of the brain...Early on, bilingualism was thought to be a disadvantage because the presence of two vocabularies would lead to delayed language development in children. However, it has since been demonstrated that bilingual individuals perform better, compared with monolinguals, on tasks that require attention, inhibition and short-term memory, collectively termed "executive control."

This "bilingual advantage" is believed to come about because of bilinguals' long-term use and management of two spoken languages. But skepticism still remains about whether these advantages are present, as they are not observed in all studies...."Given this concern, we took a different approach and instead compared gray matter volume between adult bilinguals and monolinguals. We reasoned that the experience with two languages and the increased need for cognitive control to use them appropriately would result in brain changes in Spanish-English bilinguals when compared with English-speaking monolinguals. And in fact greater gray matter for bilinguals was observed in frontal and parietal brain regions that are involved in executive control."

Gray matter of the brain has been shown to differ in volume as a function of people's experiences. A prominent finding of this type was a report that London taxi drivers have more gray matter in brain areas involved in spatial navigation.

What about being bilingual leads to these advantages?....The researchers compared gray matter in bilinguals of American Sign Language (ASL) and spoken English with monolingual users of English...."Unlike the findings for the Spanish-English bilinguals, we found no evidence for greater gray matter in the ASL-English bilinguals," Olulade says. "Thus we conclude that the management of two spoken languages in the same modality, rather than simply a larger vocabulary, leads to the differences we observed in the Spanish-English bilinguals."

Science Daily: Bilingualism delays Alzheimer's manifestation by more than four years

The symptoms of Alzheimer disease (AD) manifest themselves about four to five years later in bilinguals as opposed to monolinguals. In bilinguals, the disease onset was estimated at the age of 77, while in monolinguals, this was at the age of 73.

From Science Daily:  Bilingual brains better equipped to process information

Speaking more than one language is good for the brain, according to new research that indicates bilingual speakers process information more efficiently and more easily than those who know a single language. The benefits occur because the bilingual brain is constantly activating both languages and choosing which language to use and which to ignore, said a researcher.

From Science daily:  Bilingualism changes children's beliefs

Most young children are essentialists: They believe that human and animal characteristics are innate. That kind of reasoning can lead them to think that traits like native language and clothing preference are intrinsic rather than acquired. But a new study suggests that certain bilingual kids are more likely to understand that it's what one learns, rather than what one is born with, that makes up a person's psychological attributes.

White and gray matter of the human brain. Credit: Medline Plus, US National Library of Medicine