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Interesting study finding - that both high and low levels of magnesium is associated with a higher risk of dementia. Magnesium is an essential mineral needed for more than 300 biochemical reactions in the body. According to a large study done in the Netherlands of people who were followed for about 8 years - there was a U-shaped incidence of dementia based on their levels of magnesium. The lowest incidence was in those with "in the middle" normal levels of magnesium in the blood. All the study participants were mentally healthy when the study started.

The researchers stated that magnesium levels are considered "relatively stable over time", but a limitation of the study is that they only looked at magnesium levels once - at the beginning of the study, so they could have changed over time. Of course further studies are needed. [Other posts on magnesium and health - here, here, and here.]

Magnesium is widely available in foods. Foods that are good sources of magnesium include: spinach and other dark green leafy vegetables, almonds, cashews, peanuts, bananas, soybeans, kidney and black beans (legumes), whole grains, lentils, seeds, yogurt, brown rice, potatoes, and avocados. It is recommended that magnesium is obtained from the diet, and not from supplements (due to health risks from high doses). From Science Daily:

Both high, low levels of magnesium in blood linked to risk of dementia

People with both high and low levels of magnesium in their blood may have a greater risk of developing dementia, according to a study published in the September 20, 2017, online issue of Neurology®, the medical journal of the American Academy of Neurology.

The study involved 9,569 people with an average age of 65 who did not have dementia whose blood was tested for magnesium levels. The participants were followed for an average of eight years. During that time, 823 people were diagnosed with dementia. Of those, 662 people had Alzheimer's disease. The participants were divided into five groups based on their magnesium levels. Both those with the highest and the lowest levels of magnesium had an increased risk of dementia, compared to those in the middle group.

Both the low and high groups were about 30 percent more likely to develop dementia than those in the middle group. Of the 1,771 people in the low magnesium group, 160 people developed dementia, which is a rate of 10.2 per 1,000 person-years. For the high magnesium group, 179 of the 1,748 people developed dementia, for a rate of 11.4 per 1,000 person-years. For the middle group, 102 of the 1,387 people developed dementia, for a rate of 7.8. Kieboom noted that almost all of the participants had magnesium levels in the normal range, with only 108 people with levels below normal and two people with levels above normal[Original study.]

Surprised...is how I felt after reading this study. According to the study, activity levels and exercise in mid-life are not linked to cognitive fitness and dementia later on in life. Instead, higher levels of physical activity and exercise has a beneficial effect on the brain in the short term (e.g., within 2 years or so). This finding of no long-term benefits, but only short-term benefits to the brain from exercise, is contrary to some other (cross-sectional) studies, but is supported by another recent study ("no evidence of a neuroprotective effect of physical activity").

The beauty of this study is that it followed 646 people for 30 years (from a median age of 46 years in 1978 and 77 years in 2008). The negative is that according to this study, physical exercise in mid-life does not seem to delay or prevent the onset of dementia and Alzheimer's later on in life. Eh... From Medical Xpress:

Physical activity in midlife not linked to cognitive fitness in later years, long-term study shows

A study led by Johns Hopkins Bloomberg School of Public Health researchers that tracked activity levels of 646 adults over 30 years found that, contrary to previous research, exercise in mid-life was not linked to cognitive fitness in later yearsThe finding suggests that physical activity may not help maintain cognitive function, or help avoid or delay the onset of the debilitating conditions like dementia and Alzheimer's

The study, which appears online in the Journal of Alzheimer's Disease, did find that activity levels among study participants in the later years were associated with high cognitive function two years later. This supports earlier research findings that exercise may help to maintain cognitive fitness in the short term.

There is no known treatment or cure for Alzheimer's or dementia, syndromes that involves declining memory, confusion and eventually limited ability to perform daily tasks. To date, there are no preventive measures, such as physical exercise, brain games or a diet regimen, that have been proven to help delay or altogether prevent its onset. The researchers undertook the study because of a growing consensus that physical activity levels helps prevent Alzheimer's, however much of the evidence for this thinking is based on cross-sectional studies that compare responses from one group of participants with another at a given point in time or within a very short duration, typically several years..... That's where longitudinal studies, which look at the same group of participants over a long time, are more helpful.

The researchers used data from the Johns Hopkins Precursors study.... The researchers used responses from 1978 through 2008 from 646 participants (598 men, 48 women) to calculate so-called metabolic equivalents, which quantify physical activity levels. Participants were also asked whether they regularly exercise to a sweat. The team administered cognitive tests in 2008, and, using participants' medical records, scored for dementia through 2011. The researchers identified 28, or 4.5 percent of the cohort, to have Alzheimer's.

No physical activity measure in mid-life was associated with late-life cognitive fitness or onset of dementia. The study confirmed findings of other cross-sectional studies, that higher levels of physical activity and exercise measured close in time to the cognitive testing were associated with better cognitive functioning. The authors also looked at whether patterns of change in physical activity levels over the life span were associated with cognitive health and found no relationships.

The idea that exercise might play a role in preventing or limiting Alzheimer's makes sense, the researchers say, because physical activity, at least in mouse models, has shown less accumulation of B-amyloid plaques, which are thought to play a role in dementia, including Alzheimer's. In addition, physical activity improves blood flow to the brain, which is linked to better cognitive performance. This may explain why studies find that exercise may contribute to cognitive fitness in the short term.

Image result for eggs Remember all the dietary advice that for years told us to avoid or limit consumption of eggs - that since they were high in cholesterol, they were bad for us and would increase our risk for heart disease? And the nonsense that we should only eat the egg whites while throwing out the yolks? Hah...That advice was wrong, which another recent study confirms.

Eggs are an amazingly nutritious food. They’re loaded with high quality protein, healthy fats, vitamins, minerals, high in choline (a brain nutrient), biotin, antioxidants, lutein, and zeaxanthin. One review of studies (involving millions of people) looked at whole egg consumption  and found that high egg consumption (up to one egg per day) is not associated with increased risk of coronary heart disease or stroke, and in fact there was a reduced risk of hemorrhagic stroke. Only among diabetics was there an elevated risk of coronary heart disease with high egg consumption (up to 1 egg per day). Another study found a lower risk of type 2 diabetes in middle-aged men (see post).

A recent study from Finland found that neither cholesterol nor egg intake (eating one egg per day) is associated with an increased risk of dementia or Alzheimer's disease in Finnish men who were followed for 22 years. Instead, eating eggs was associated with better cognitive performance in certain areas such as executive function, which includes memory, problem solving, and planning (they were given neuropsychological tests). From Science Daily:

High cholesterol intake and eggs do not increase risk of memory disorders

A new study from the University of Eastern Finland shows that a relatively high intake of dietary cholesterol, or eating one egg every day, are not associated with an elevated risk of dementia or Alzheimer's disease. Furthermore, no association was found in persons carrying the APOE4 gene variant that affects cholesterol metabolism and increases the risk of memory disorders. APOE4 is common in Finland.

The dietary habits of 2,497 men aged between 42 and 60 years and with no baseline diagnosis of a memory disorder were assessed at the onset the Kuopio Ischaemic Heart Disease Risk Factor Study, KIHD, in 1984-1989 at the University of Eastern Finland. During a follow-up of 22 years, 337 men were diagnosed with a memory disorder, 266 of them with Alzheimer's disease. 32.5 per cent of the study participants were carriers of APOE4.

The study found that a high intake of dietary cholesterol was not associated with the risk of dementia or Alzheimer's disease -- not in the entire study population nor in the carriers of APOE4. Moreover, the consumption of eggs, which are a significant source of dietary cholesterol, was not associated with the risk of dementia or Alzheimer's disease. On the contrary, the consumption of eggs was associated with better results in certain tests measuring cognitive performance

 Another study finding a link between air pollution and negative health effects - this time a higher incidence of decline in cognitive functioning  and dementia in older women (65 and older) exposed to fine particles (PM2.5 ). These extremely small particles from vehicle emissions are a major source of urban air pollution throughout the world. These results match other studies finding a link with urban air pollution, especially vehicle traffic, to negative effects on the brain (dementia, cognitive decline, shrinking of the brain, etc.). The researchers also exposed mice to this air pollution for 15 weeks and then studied their brains for evidence of degenerative effects in their brains - and yes, they did find them.

The researchers found that the adverse effects of fine particulate air pollution was stronger in both women and mice who had the APOE4 gene, a genetic variation that increases the risk for Alzheimer's disease. They said that while the air pollution has negative effects in general, that having the APOE4 gene interacted with the air pollution. The researchers also wrote that the mice studies they did showed that "...exposure to urban airborne particulates can intensify amyloid accumulation and neurodegeneration". Medical Xpress:

Air pollution may lead to dementia in older women

Tiny air pollution particles—the type that mainly comes from power plants and automobiles—may greatly increase the chance of dementia, including Alzheimer's disease, according to USC-led research. Scientists and engineers found that older women who live in places with fine particulate matter exceeding the U.S. Environmental Protection Agency's standard are 81 percent more at risk for global cognitive decline and 92 percent more likely to develop dementia, including Alzheimer's.

If their findings hold up in the general population, air pollution could be responsible for about 21 percent of dementia cases, according to the study. "Microscopic particles generated by fossil fuels get into our body directly through the nose into the brain," said University Professor Caleb Finch at the USC Leonard Davis School of Gerontology and co-senior author of the study. "Cells in the brain treat these particles as invaders and react with inflammatory responses, which over the course of time, appear to exacerbate and promote Alzheimer's disease.

The adverse effects were stronger in women who had the APOE4 gene, a genetic variation that increases the risk for Alzheimer's. "Our study .....provides the inaugural scientific evidence of a critical Alzheimer's risk gene possibly interacting with air particles to accelerate brain aging," said Jiu-Chiuan Chen, co-senior author of the study....[Their study] adds to an emerging body of research from around the world that links air pollution to dementia. The offending pollutants—known as PM2.5—are fine, inhalable particles with diameters 2.5 micrometers or smaller. A human hair is about 70 micrometers in diameter, making it 30 times larger than the largest PM2.5. The researchers analyzed data of 3,647 65- to 79-year-old women from the Women's Health Initiative Memory Study (WHIMS). These women lived across 48 states and did not have dementia when they enrolled.

USC scientists chronically exposed female mice carrying the APOE4 gene to nano-sized air pollution for 15 weeks. Compared to the control group, mice predisposed to Alzheimer's disease accumulated as much as 60 percent more amyloid plaque, the toxic clusters of protein fragments that further the progression of Alzheimer's.

In other studies, Chen and his colleagues linked long-term exposure to high PM2.5 levels to smaller gray and white matter volumes in important areas such as the frontal lobe, which carries out thinking, decision-making and planning. For every 3.5 micrograms of PM2.5 per cubic meter of air, white matter (insulated nerve fibers that connect different brain regions) decreased by 6 cubic centimeters, according to one earlier study. [see post]

 More great news about drinking coffee daily - for women. Older women (between ages of 65 to 80 at the start of the study) reporting drinking higher amounts of caffeinated beverages (about 261 mg which is about 2 to 3 cups of coffee per day) had a lower incidence of dementia and cognitive impairment over a 10 year period (as compared to the low caffeine group). The low caffeine group averaged 64 mg of caffeine per day.  Other studies also found a reduction in "cognitive decline" in older people with coffee consumption. This study, among others, is more evidence of caffeine being "neuroprotective". NOTE: an 8-ounce cup of brewed coffee contains about 95 mg of caffeine, 8-ounces of brewed black tea contains about 47 mg, a 12-ounce can of carbonated cola contains 33 mg, and 8-ounces of decaffeinated coffee has about 5 mg of caffeine. Science Daily:

For women, caffeine could be ally in warding off dementia

Among a group of older women, self-reported caffeine consumption of more than 261 mg per day was associated with a 36 percent reduction in the risk of incident dementia over 10 years of follow-up. This level is equivalent to two to three 8-oz cups of coffee per day, five to six 8-oz cups of black tea, or seven to eight 12-ounce cans of cola.

"The mounting evidence of caffeine consumption as a potentially protective factor against cognitive impairment is exciting given that caffeine is also an easily modifiable dietary factor with very few contraindications," said Ira Driscoll, PhD, the study's lead author and a professor of psychology at the University of Wisconsin-Milwaukee. "What is unique about this study is that we had an unprecedented opportunity to examine the relationships between caffeine intake and dementia incidence in a large and well-defined, prospectively-studied cohort of women."

The findings come from participants in the Women's Health Initiative Memory Study, which is funded by the National Heart, Lung, and Blood Institute. Driscoll and her research colleagues used data from 6,467 community-dwelling, postmenopausal women aged 65 and older who reported some level of caffeine consumption. Intake was estimated from questions about coffee, tea, and cola beverage intake, including frequency and serving size.

In 10 years or less of follow-up with annual assessments of cognitive function, 388 of these women received a diagnosis of probable dementia or some form of global cognitive impairment. Those who consumed above the median amount of caffeine for this group (with an average intake of 261 mg per day) were diagnosed at a lower rate than those who fell below the median (with an average intake of 64 mg per day). The researchers adjusted for risk factors such as hormone therapy, age, race, education, body mass index, sleep quality, depression, hypertension, prior cardiovascular disease, diabetes, smoking, and alcohol consumption. (The original study in the Journal of Gerontology.)

 Another study showing big problems with anticholinergics, which are in many popular medicines - both non-prescription and prescription (e.g., Chlor-Trimeton, Benadryl, Tavist, Dimetapp). An earlier study with older adults found a dose-response link with dementia, but the current study explored this issue further. They followed 2 groups of  "cognitively normal older adults" in their early 70s for several years: those who took anticholinergic medicines and those who did not take anticholinergic medicines. They found that those who took anticholinergic medicines had reduced brain volume (brain shrinking) and cognitive decline (when compared to those who did not take anticholinergic medicines). The researchers summarized their findings as the "use of anticholinergic medication was associated with increased brain atrophy and dysfunction and clinical decline". This finding was greatest for those taking drugs with the most anticholinergic activity.

See a list of anticholinergic medicines  from the Aging Brain Program of the Indiana University Center for Aging Research. Definitely try to avoid medicines with a score of 2 (medium effect) or 3 (high effect), but I would even be cautious about score 1 (low effect) medicines - use all medicines only as long as absolutely needed. My one very important question is: If these effects are found in older adults, what do anticholinergics do to younger brains, especially the developing brains of children? From Medical Xpress:

Brain scans link physical changes to cognitive risks of widely used class of drugs

Older adults might want to avoid a using class of drugs commonly used in over-the-counter products such as nighttime cold medicines due to their links to cognitive impairment, a research team led by scientists at Indiana University School of Medicine has recommended. Using brain imaging techniques, the researchers found lower metabolism and reduced brain sizes among study participants taking the drugs known to have an anticholinergic effect, meaning they block acetylcholine, a nervous system neurotransmitter.

Previous research found a link between between the anticholinergic drugs and cognitive impairment and increased risk of dementia.....Drugs with anticholinergic effects are sold over the counter and by prescription as sleep aids and for many chronic diseases including hypertension, cardiovascular disease, and chronic obstructive pulmonary disease. A list of anticholinergic drugs and their potential impact is at http://www.agingbraincare.org/uploads/products/ACB_scale_-_legal_size.pdf.

Scientists have linked anticholinergic drugs and cognitive problems among older adults for at least 10 years. A 2013 study by scientists at the IU Center for Aging Research and the Regenstrief Institute found that drugs with a strong anticholinergic effect cause cognitive problems when taken continuously for as few as 60 days. Drugs with a weaker effect could cause impairment within 90 days.

The current research project involved 451 participants, 60 of whom were taking at least one medication with medium or high anticholinergic activity. The participants were drawn from a national Alzheimer's research project....and the Indiana Memory and Aging Study. To identify possible physical and physiological changes that could be associated with the reported effects, researchers assessed the results of memory and other cognitive tests, positron emission tests (PET) measuring brain metabolism, and magnetic resonance imaging (MRI) scans for brain structure.

The cognitive tests revealed that patients taking anticholinergic drugs performed worse than older adults not taking the drugs on short-term memory and some tests of executive function, which cover a range of activities such as verbal reasoning, planning, and problem solving. Anticholinergic drug users also showed lower levels of glucose metabolism—a biomarker for brain activity—in both the overall brain and in the hippocampus, a region of the brain associated with memory and which has been identified as affected early by Alzheimer's disease. The researchers also found significant links between brain structure revealed by the MRI scans and anticholinergic drug use, with the participants using anticholinergic drugs having reduced brain volume and larger ventricles, the cavities inside the brain.

 A new study has confirmed an association between proton pump inhibitors (PPIs) — drugs that treat heartburn, peptic ulcers, and other acid-related disorders of the upper gastrointestinal tract — and increased risk for dementia in older patients. An earlier study by the same researchers found the same link between PPI use and dementia risk. The drugs work by lowering the amount of acid produced by the stomach. PPIs are among the most frequently prescribed drugs, and include omeprazole (Losec), esomeprazole (Nexium), lansoprazole (Prevacid), and the over-the-counter medication Olex.

The U.S. Food and Drug Administration have warned people to take them for the shortest period possible, namely a few weeks, and only for serious acid reflux, ulcers, or stomach bleeding. Other problems linked to long-term use are: fractures, pneumonia, increased rates of C. difficile, low magnesium levels, and chronic kidney disease. From Science Daily:

Proton pump inhibitors may be associated with increased risk of Dementia

The use of proton pump inhibitors, the popular medications used to treat gastroesophageal reflux and peptic ulcers, may be associated with an increased risk of dementia in a study using data from a large German health insurer, according to an article published online by JAMA Neurology.  The use of proton pump inhibitors (PPIs) has increased among older patients and PPIs are among the most frequently used classes of drugs.

Britta Haenisch, Ph.D., of the German Center for Neurodegenerative Diseases, Bonn, Germany, and coauthors examined the association between the use of PPIs and the risk of dementia using data from 2004 to 2011 on inpatient and outpatient diagnoses and drug prescriptions. Regular PPI use was at least one PPI prescription in each quarter of an 18-month interval.

The study population included 218,493 individuals 75 or older before 144,814 individuals were excluded, leaving 73,679 individuals included in the final analysis. The authors identified 29,510 patients who developed dementia during the study period. Regular users of PPIs (2,950 patients, mostly female and average age nearly 84) had a 44 percent increased risk of dementia compared with those (70,729 patients, mostly female and average age 83) not receiving PPI medication, according to the results.

"The present study can only provide a statistical association between PPI use and risk of dementia. The possible underlying causal biological mechanism has to be explored in future studies. 

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.

 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.

Big question: will vitamin D supplementation prevent cognitive decline? And what should be a daily supplement dose for adults? An earlier post cited a Medscape article suggesting that taking 1000 IU of vitamin D3 daily would be a good daily level of supplementation. From Medscape:

Vitamin D Deficiency Predicts Cognitive Decline

A new study supports a link between low levels of vitamin D and increased risk for cognitive decline, prompting calls for clinical trials to test whether vitamin D supplementation may delay or prevent dementia. In a group of cognitively intact older adults, serum 25-hydroxyvitamin D (25OHD) levels below 75 nmol/L at the outset predicted cognitive decline over roughly the next 4 years, independent of other factors.

For this analysis, the researchers looked at data on 1927 community-dwelling elderly individuals (mean age, 73.9 years) participating in the Italian population-based cohort study, Progetto Veneto Anziani (Pro.V.A.).

Dr Toffanello and colleagues say studies are needed to evaluate whether vitamin D supplementation might help to delay the cognitive decline, especially in patients who already have cognitive impairment.

David J. Llewellyn, PhD, from the University of Exeter Medical School in the United Kingdom, who has studied vitamin D and cognitive function but wasn't involved in this study, agrees. He told Medscape Medical News that this new study "effectively replicates" a 2010 study by his group showing a link between low vitamin D levels and an increased risk for cognitive decline. He said the Pro.V.A . study results are also consistent with a study his group published just this year inNeurology. That study suggested older patients with vitamin D levels below 50 nmol/L have about a 122% increased risk for dementia compared with those with higher levels.