Being too skinny also poses a dementia risk?
Being obese can increase the risk of Alzheimer’s Disease by as much as 80 per cent, according to a study in the May issue of Obesity Reviews.
It is harder to tease out harmful effects of low weight as compared to overweight because people who have undiagnosed diseases often lose weight before getting diagnosed. So the population of skinny people include people who are about to get diagnosed with cancer or some other disease. The longer a group gets followed the less that bias influences the results.
But it’s not just weight gain that poses a risk. People who are underweight also have an elevated risk of dementia, unlike people who are normal weight or overweight.
US researchers carried out a detailed review of 10 international studies published since 1995, covering just over 37,000 people, including 2,534 with various forms of dementia. Subjects were aged between 40 and 80 years when the studies started, with follow-up periods ranging from three to 36 years.
The review, which included studies from the USA, France, Finland, Sweden and Japan, also included a sophisticated meta-analysis of seven of the studies, published between 2003 and 2007 with a follow-up period of at least five years.
All kinds of dementia were included, with specific reference to Alzheimer’s Disease and to vascular dementia – where areas of the brain stop functioning because the blood vessels that supply them are damaged by conditions such as high blood pressure or heart disease.
“Our meta-analysis showed that obesity increased the relative risk of dementia, for both sexes, by an average of 42 per cent when compared with normal weight” says Dr Youfa Wang, Associate Professor of International Health and Epidemiology at Johns Hopkins Bloomberg School of Public Health, Baltimore.
“And being underweight increased the risk by 36 per cent.
“But when we looked specifically at Alzheimer’s Disease, the increased risk posed by obesity was 80 per cent. The increased risk for people with vascular dementia was 73 per cent.
The harmful effects of obesity suggest that bariatric surgery ought to be considered by the chronically obese. Here's another reason: bariatric surgery might cure type 2 insulin resistant diabetes.
A beer belly rots your brain even though the beer might not be at fault.
ST. PAUL, Minn. – People with larger stomachs in their 40s are more likely to have dementia when they reach their 70s, according to a study published in the March 26, 2008, online issue of Neurology®, the medical journal of the American Academy of Neurology.
The study involved 6,583 people age 40 to 45 in northern California who had their abdominal fat measured. An average of 36 years later, 16 percent of the participants had been diagnosed with dementia. The study found that those with the highest amount of abdominal fat were nearly three times more likely to develop dementia than those with the lowest amount of abdominal fat.
So then would belly liposuction reduce your risk of Alzheimer's Disease?
A lot of people are walking around (or sitting) with hazardous bellies.
“Considering that 50 percent of adults in this country have an unhealthy amount of abdominal fat, this is a disturbing finding,” said study author Rachel A. Whitmer, PhD, a Research Scientist of the Kaiser Permanente Division of Research in Oakland, CA, and member of the American Academy of Neurology. “Research needs to be done to determine what the mechanisms are that link abdominal obesity and dementia.”
Having a large abdomen increased the risk of dementia regardless of whether the participants were of normal weight overall, overweight, or obese, and regardless of existing health conditions, including diabetes, stroke and cardiovascular disease.
Those who were overweight and had a large belly were 2.3 times more likely to develop dementia than people with a normal weight and belly size. People who were both obese and had a large belly were 3.6 times more likely to develop dementia than those of normal weight and belly size. Those who were overweight or obese but did not have a large abdomen had an 80-percent increased risk of dementia.
This study didn't prove the direction of causation. But the results are highly suggestive.
Yet Seshadri also notes that factors other than fat could be responsible for the results. Whitmer's team controlled for some of these, such as education and rates of other illnesses. But other issues were not taken into account. Overweight people are less likely to exercise, for instance. Physical activity is known to decrease obesity risk, as well as being psychologically beneficial.
Whitmer acknowledges this short-coming, but points out that the dementia rates were greater among those who were not overweight during middle-age, but did have high levels of belly fat. These people are likely to have exercised since their weight was normal, she says, but they still went on to develop cognitive problems.
Pay attention to comments from obesity researcher Rudolph Liebel of Columbia University in this previous post. Note that fat cells are now known to secrete at least a couple of dozen hormones and other signalling compounds. Some of those compounds cross the blood-brain barrier. Fat is not a passive pile of blubber. Belly fat in particular secretes more stuff than other areas of fat. The fat on your belly is sending out messages that are messing up your brain and body.
The new work suggests long-ago lead exposure can make an aging person's brain work as if it's five years older than it really is. If that's verified by more research, it means that sharp cuts in environmental lead levels more than 20 years ago didn't stop its widespread effects.
"We're trying to offer a caution that a portion of what has been called normal aging might in fact be due to ubiquitous environmental exposures like lead," says Dr. Brian Schwartz of Johns Hopkins University.
A longitudinal study found that those with higher bone lead levels seemed to age more rapidly.
Hu and his colleagues took a slightly different approach in a 2004 study of 466 men with an average age of 67. Those men took a mental-ability test twice, about four years apart on average. Those with the highest bone lead levels showed more decline between exams than those with smaller levels, with the effect of the lead equal to about five years of aging.
Nobody is claiming that lead is the sole cause of age-related mental decline, but it appears to be one of several factors involved, Hu stressed.
Cumulative lead exposure seems to reduce cognitive function.
In a study of almost 1,000 persons 50–70 years of age randomly selected from the general population in the Baltimore Memory Study (BMS), a cross-sectional analysis showed that relatively low current blood lead levels were not associated with cognitive domain scores. However, moderate tibia lead levels (mean ~ 19 µg/g) were significantly associated with worse performance in all seven cognitive domains (Shih et al. 2006). Thus, in the environmental studies of older adults, the most consistent findings across studies are associations between bone lead levels and cognitive function. The associations in the BMS were cross-sectional, whereas the predominant associations in the NAS were with change in cognitive function over time, although a significant cross-sectional association with MMSE score was also observed in this sample. Taken together, these data suggest that at environmental exposure levels, the effects of cumulative exposure are more pronounced than recent effects of current exposure. The absence of associations in the Stokes et al. (1998) study could be because of the younger age of studied subjects, the very low current blood and tibia lead levels, or the inadequacy of tibia lead in the third decade of life to estimate early life dose (Hoppin et al. 2000).
So what to do about your accumulated bone lead? One possible long term response might be thiamine (or thiamin - vitamin B1) supplementation. Thamine enhances lead excretion in rodents and also in sheep and other animals.
More evidence that fish oils really are good for you.
Many Alzheimer's researchers have long touted fish oil, by pill or diet, as an accessible and inexpensive "weapon" that may delay or prevent this debilitating disease. Now, UCLA scientists have confirmed that fish oil is indeed a deterrent against Alzheimer's, and they have identified the reasons why.
Reporting in the current issue of the Journal of Neuroscience, now online, Greg Cole, professor of medicine and neurology at the David Geffen School of Medicine at UCLA and associate director of UCLA's Alzheimer Disease Research Center, and his colleagues report that the omega-3 fatty acid docosahexaenoic acid (DHA) found in fish oil increases the production of LR11, a protein that is found at reduced levels in Alzheimer's patients and which is known to destroy the protein that forms the "plaques" associated with the disease.
The plaques are deposits of a protein called beta amyloid that is thought to be toxic to neurons in the brain, leading to Alzheimer's. Since having high levels of LR11 prevents the toxic plaques from being made, low levels in patients are believed to be a factor in causing the disease.
I ate a large piece of Salmon on Christmas Day and now I feel even better about it.
DHA also boosted LR11 in human cells grown in culture.
"We found that even low doses of DHA increased the levels of LR11 in rat neurons, while dietary DHA increased LR11 in brains of rats or older mice that had been genetically altered to develop Alzheimer's disease," said Cole, who is also associate director of the Geriatric Research Center at the Veterans Affairs Medical Center.
To show that the benefits of DHA were not limited to nonhuman animal cells, the researchers also confirmed a direct impact of DHA on human neuronal cells in culture as well. Thus, high levels of DHA leading to abundant LR11 seem to protect against Alzheimer's, Cole said, while low LR11 levels lead to formation of the amyloid plaques.
Since the oceans don't have enough fish in them we really need land crops genetically engineered to have high levels of omega 3 fatty acids.
Not convinced yet? See my previous posts Omega 3 Fatty Acids In Fish Delay Alzheimer's In Mice, Fish In Diet Slows Rate Of Cognitive Decline, Omega 3 Fatty Acids Might Slow Alzheimers Disease, and Omega 3 Fatty Acids Protect Against Parkinsons Disease? for more on brain aging benefits of omega 3 fatty acids.
We need to slow the aging of our brains for the day when brain rejuvenation therapies become available. The more neurons we have left at that point the more that can be repaired and restored.
Here is yet another reason to eat more salmon.
Quebec City, November 26, 2007—Omega-3 fatty acids protect the brain against Parkinson’s disease, according to a study by Université Laval researchers published in the online edition of the FASEB Journal, the journal of the Federation of American Societies for Experimental Biology. This study, supervised by Frederic Calon and Francesca Cicchetti, is the first to demonstrate the protective effect of a diet rich in omega-3 fatty acids against Parkinson’s.
Parkinson’s disease is caused by the progressive death of the neurons responsible for producing dopamine, a neurotransmitter closely linked with movement control. The disease is usually diagnosed when 50 to 80% of these neurons are already dead, and there is currently no medication to stop that process.
The Université Laval research team’s findings could help prevent the disease and, potentially, slow down its progression.
The researchers observed that when mice were fed an omega-3 rich diet, they seemed immune to the effect of MPTP, a toxic compound that causes the same damage to the brain as Parkinson’s. “This compound, which has been used for more than 20 years in Parkinson’s research, works faster than the disease itself and is just as effective in targeting and destroying the dopamine-producing neurons in the brain,” points out Calon.
By contrast, another group of mice that were fed an ordinary diet developed the characteristic symptoms of the disease when injected with MPTP, including a 31% drop in dopamine-producing neurons and a 50% decrease in dopamine levels.
Analyses revealed that omega-3 fatty acids—in particular DHA (docosahexaenoic acid), a specific type of omega-3—had replaced the omega-6 fatty acids already present in the brains of the mice that had been given omega-3 supplementation.
I eat salmon 5 times a week. Most other omega 3 fatty acid sources are inferior in comparison. Though mackerel, sardines, and herring have high omega 3 concentrations close to salmon. But if you are worried about mercury then avoid mackerel since it has very high mercury concentrations.
MIT researchers have shown that a cocktail containing three compounds normally in the blood stream promotes growth of new brain connections and improves cognitive function in rodents. The treatment is now being tested in Alzheimer's patients and could hold promise for other brain diseases and injuries.
The mixture, which includes a type of omega-3 fatty acid, is part of a new approach to attacking Alzheimer's. That approach focuses on correcting the loss of synapses, or connections between neurons, which characterizes the disease.
Each of the components of the mixture boosted synapse growth. But the combination of the 3 substances produced the biggest increase.
In the Brain Research paper, the MIT team reported that rodents given a cocktail of DHA (a type of omega-3 fatty acid), uridine and choline showed a greatly increased concentration of dendritic spines, which receive messages in the postsynaptic neuron. That indicates that synapse regeneration has occurred, which is unusual, Wurtman said.
Synapse regrowth could also prove an effective treatment for other brain diseases, such as Parkinson's, or for brain injuries, he said.
Salmon and eggs might deliver a double punch for increased brain performance.
Omega-3 fatty acids are not produced in the body but are found in a variety of sources, including fish, eggs, flaxseed and meat from grass-fed animals. Choline can be synthesized in the body and obtained through the diet; it is found in meats, nuts and eggs. Uridine cannot be obtained from food sources, but is a component of human breast milk and can be produced in the body.
Nuts and eggs and salmon. That's the ticket.
Of course fish, fruits, and vegetables slow brain aging. You already know that. But the purpose of my posting the studies on diet and aging is to remind you that, yes, the bad foods really are bad for you and the good foods really are good for you. There's a big difference between an ideal diet and a typical diet. An ideal diet delivers benefits in many forms. When you eat wisely you aren't just reducing your risk of cancer and heart disease. Fish, fruit, and vegetables really are good for your brain.
ST. PAUL, Minn. – A diet rich in fish, omega-3 oils, fruits and vegetables may lower your risk of dementia and Alzheimer’s disease, whereas consuming omega-6 rich oils could increase chances of developing memory problems, according to a study published in the November 13, 2007, issue of Neurology®, the medical journal of the American Academy of Neurology.
Do you need to know the statistical details in order to improve your diet? If not, go on to the next story. If you really need to know then keep reading. Or if you are already eating a wise scientifically informed diet then read on so you that can feel really good about yourself and your health choices.
I so do not want to get Alzheimer's and forget who I am or where's the bathroom or which house I live in or whether I ate breakfast or who my friends are. Isn't that a really terrible way to go? Luckily, we can change our odds with better diet choices.
For the study, researchers examined the diets of 8,085 men and women over the age of 65 who did not have dementia at the beginning of the study. Over four years of follow-up, 183 of the participants developed Alzheimer’s disease and 98 developed another type of dementia.
The study found people who regularly consumed omega-3 rich oils, such as canola oil, flaxseed oil and walnut oil, reduced their risk of dementia by 60 percent compared to people who did not regularly consume such oils. People who ate fruits and vegetables daily also reduced their risk of dementia by 30 percent compared to those who didn’t regularly eat fruits and vegetables.
Vegetables aren't much fun unless someone with considerable culinary skills transforms them into something tasty. Still, I managed to eat half a head of cabbage today.
But if you have the ApoE4 genetic variant the story is not so good. Does any kind of food help those who have ApoE4?
The study also found people who ate fish at least once a week had a 35-percent lower risk of Alzheimer’s disease and 40-percent lower risk of dementia, but only if they did not carry the gene that increases the risk of Alzheimer’s, called apolipoprotein E4, or ApoE4.
“Given that most people do not carry the ApoE4 gene, these results could have considerable implications in terms of public health,” said study author Pascale Barberger-Gateau, PhD, of INSERM, the French National Institute for Health and Medical Research, in Bordeaux, France. “However, more research is needed to identify the optimal quantity and combination of nutrients which could be protective before implementing nutritional recommendations.”
In addition, the study found people who did not carry the ApoE4 gene and consumed an unbalanced diet characterized by regular use of omega-6 rich oils, but not omega-3 rich oils or fish were twice as likely to develop dementia compared to those who didn’t eat omega-6 rich oils, which include sunflower or grape seed oil. The study did not find any association between consuming corn oil, peanut oil, lard, meat or wine and lowering risk of dementia.
I find it curious that corn oil and peanut oil didn't appear to deliver a net harm. However, given that you are limited in how many calories you can consume corn and peanut oil really have a cost: They reduce the amount of healthier oils and healthier other foods you can eat.
Beta carotene, a nutrient found in many vegetables and fruits, seems to slow down cognitive decline if taken for 15 years or longer.
Men who take beta carotene supplements for 15 years or longer may have less cognitive decline, according to a report in the November 12 issue of Archives of Internal Medicine, one of the JAMA/Archives journals.
Decreases in cognitive ability—thinking, learning and memory skills—strongly predict dementia, a growing public health issue, according to background information in the article. Long-term cellular damage from “oxidative stress” may be a major factor in cognitive decline. Some evidence suggests that antioxidant supplements may help preserve cognition, although previous studies have been inconclusive, the authors note.
Francine Grodstein, Sc.D., of Brigham and Women’s Hospital (BWH) and Harvard Medical School, Boston, and colleagues studied the antioxidant beta carotene and its effect on cognitive ability in two groups of men. The long-term group included 4,052 men who in 1982 had been randomly assigned to take placebo or 50 milligrams of beta carotene every other day. Between 1998 and 2001, an additional 1,904 men were randomly assigned to one of the two groups. Both groups were followed through 2003, completing yearly follow-up questionnaires with information about their health and their compliance with taking the pills. The men were assessed by telephone for cognitive function at least once between 1998 and 2002.
Rather than take beta carotene you are better off eating the fruits and vegetables that contain the beta carotene and other antioxidants.
People with Alzheimer's Disease who ate a Mediterranean diet (more monounsaturated fats, more fruits and vegetables, beans, whole grains, less meat and dairy) lived 4 years long than those not on a the Mediterranean diet.
Scarmeas' group found that patients whose consumption habits most closely tracked that of the Mediterranean diet were 76 percent less likely to die in the study period than those whose food intake least mimicked the diet.
Compared with those whose diets most closely resembled a Western diet, Alzheimer's patients who most closely followed the Mediterranean diet lived an average of four years longer.
A more moderate degree of adherence to the Mediterranean diet still translated into extra 1.3 years of survival, the researchers said. That's equal to a 29 percent to 35 percent reduced risk for dying during the study period.
The same Columbia University Medical Center team led by Nikolaos Scarmeas previously reported that the Mediterranean diet appears to lower the risk of getting Alzheimer's in the first place.
Compared to the third of people who scored worst on the Mediterranean diet scores, those in the mid-ranking group had a 15% to 21% lower risk of developing Alzheimer's disease, and those with the highest score had a 39% to 40% lower risk.
Also see this abstract of some of their previous work on this topic.
The Mediterranean diet is a more doable kind of diet than a lot of others. It doesn't eliminate fats. It just shifts which ones you eat. Ditto for carbs. A lot of people can eat a Mediterranean diet without feeling heavily deprived. But you have to commit to doing it. Cook the beans, buy the nuts and seeds. Switch from polyunsaturated oils to monounsaturates like olive oil and canola. Also, cut back on meat and dairy and eat more fish.
Periodically I try to find ways to improve my diet. It is already pretty good. But I just ordered a flax seed grinder. I'll let you all know how flax seed grinding works out.
Update: Reminder: Not excited about the notion of eating a better diet in order to slow the inevitable decay of old age? Feel like, hey, what's the point? The point is to live long enough to still have a functioning mind when rejuvenation therapies become available. Yes, the rejuvenation therapies are coming. They aren't distant science fiction prospects. We'll have at least some useful stem cell therapies in 10 years and many more in 20 years. We will have gene therapies and methods for growing replacement organs too. Hang in there and slow the decay. Eventually it'll be possible to reverse the decay.
A recurring FuturePundit theme: The toughest part of the body to rejuvenate is going to be the brain. Therefore anything that slows brain aging is especially valuable for those who want to survive until the reversal of aging becomes possible. With that thought in mind: Looks like a cup of coffee might slow your brain aging.
ST. PAUL, MN- Caffeine may help older women protect their thinking skills, according to a study published in the August 7, 2007, issue of Neurology®, the medical journal of the American Academy of Neurology.
The study found that women age 65 and older who drank more than three cups of coffee (or the equivalent in tea) per day had less decline over time on tests of memory than women who drank one cup or less of coffee or tea per day. The results held up even after researchers adjusted for other factors that could affect memory abilities, such as age, education, disability, depression, high blood pressure, medications, cardiovascular disease, and other chronic illnesses.
“Caffeine is a psychostimulant which appears to reduce cognitive decline in women,” said study author Karen Ritchie, PhD, of INSERM, the French National Institute for Health and Medical Research, in Montpellier, France. “While we have some ideas as to how this works biologically, we need to have a better understanding of how caffeine affects the brain before we can start promoting caffeine intake as a way to reduce cognitive decline. But the results are interesting – caffeine use is already widespread and it has fewer side effects than other treatments for cognitive decline, and it requires a relatively small amount for a beneficial effect.”
The study involved 7,000 people whose cognitive abilities and caffeine consumption were evaluated over four years. Compared to women who drank one cup or less of coffee per day, those who drank over three cups were less likely to show as much decline in memory. Moreover, the benefits increased with age – coffee drinkers being 30 percent less likely to have memory decline at age 65 and rising to 70 percent less likely over age 80.
Now, do I have to take up coffee drinking or watch my mental lights go out? I'd really like to know whether the caffeine or some other compound in the coffee delivers the protective benefit.
There are other ways to get the caffeine of course. For example, 3.5 ounces of dark chocolate has as much caffeine as 8 ounces of instant coffee. Yet another reason to eat chocolate. Black tea contains more than twice as much caffeine as green tea.
Eat your beans and green leafy vegetables.
Folic acid supplementation can reduce the risk of stroke by 18% or more, conclude authors of an Article published in this week's edition of The Lancet.
But the authors and an accompanying comment caution that there remains controversy as to whether folic acid supplementation can lead to improved outcomes for other cardiovascular conditions.
Professor Xiaobin Wang, Children's Memorial Hospital and Children's Memorial Research Center, Northwestern University Feinberg School of Medicine, Chicago, USA, and colleagues did a meta-analysis (a study combining previous trials) of eight trials of folic acid that had stroke reported as one of the endpoints.
Folic acid supplementation lowers the concentrations homocysteine in the blood. High amounts of homocysteine in the blood are thought to increase the risk of stroke, as well as that of cardiovascular disease and deep vein thrombosis.
They found folic acid supplementation reduced the relative risk of stroke by an average of 18 per cent. In subgroup analyses, an even greater reduction of risk was seen when the treatment lasted over 36 months (29% less risk); if it reduced the concentration of homocysteine in the blood by more than 20% (23% less risk); or if the patient had no previous history of stroke (25% less risk).
The study also found that in areas that did not already have supplementation through fortified or partly fortified grain, folic acid supplementation decreased the risk of stroke by 25%.
Should blood tests for homocysteine levels become as commonplace as blood tests for cholesterol and lipids? Also, while I'm at it, should vitamin D blood tests also become commonplace?
Look ahead 20 years and I expect many people will walk around with implanted nanodevices that do in situ blood tests. People will get their blood tests and recommended dietary recommendations from their cell phones which will query their implanted nanodevices. Or maybe they'll have implanted headphones and the implants will tell us what we need? Or why not implant display devices on the optic nerves and just show the test results by stimulating a pattern on optic nerves to cause us to see test result data?
Epicatechin and exercise boost memory in mice.
WASHINGTON, DC May 29, 2007 – A natural compound found in blueberries, tea, grapes, and cocoa enhances memory in mice, according to newly published research. This effect increased further when mice also exercised regularly.
"This finding is an important advance because it identifies a single natural chemical with memory-enhancing effects, suggesting that it may be possible to optimize brain function by combining exercise and dietary supplementation," says Mark Mattson, PhD, at the National Institute on Aging.
The compound, epicatechin, is one of a group of chemicals known as flavonols and has been shown previously to improve cardiovascular function in people and increase blood flow in the brain. Flavonols are found in some chocolate. Henriette van Praag, PhD, of the Salk Institute, and colleagues there and at Mars, Inc., showed that the combination of exercise and a diet with epicatechin also promoted structural and functional changes in the dentate gyrus, a part of the brain involved in the formation of learning and memory. The findings, published in the May 30 issue of The Journal of Neuroscience, suggest that a diet rich in flavonols may help reduce the incidence or severity of neurodegenerative disease or cognitive disorders related to aging.
You can also get epicatechin from fruits and tea. Anyone know a good table listing the epicatechin content of many foods?
A fatty acid found in fish slows tau protein accumulation in genetically modified mice.
Irvine, Calif. — A type of omega-3 fatty acid may slow the growth of two brain lesions that are hallmarks of Alzheimer’s disease, UC Irvine scientists have discovered. The finding suggests that diets rich in docosahexaenoic acid (DHA) can help prevent the development of Alzheimer’s disease later in life.
This study with genetically modified mice is the first to show that DHA, an omega-3 fatty acid, can slow the accumulation of tau, a protein that leads to the development of neurofibrillary tangles. Such tangles are one of two signature brain lesions of Alzheimer’s disease. DHA also was found to reduce levels of the protein beta amyloid, which can clump in the brain and form plaques, the other Alzheimer’s lesion.
Previous studies have shown that DHA may have therapeutic value for Alzheimer’s patients, but this research is among the first to show that it may delay the onset of the disease. DHA is found in fish, eggs, organ meats, micro-algae, fortified foods and food supplements.
Since fisheries around the world are getting depleted by excessive demand for fish we really need genetically engineered crop plants that contain more omega 3 fatty acids such as DHA and EPA (eicosapentanoic acid). Monsanto, Dupont, BASF and other companies are chasing this goal.
Big coffee drinkers experience less cognitive decline as they age.
Six hundred and seventy six healthy men born between 1900 and 1920 from Finland, Italy and the Netherlands participated in a 10-year prospective cohort study.
...
Results:Men who consumed coffee had a 10-year cognitive decline of 1.2 points (4%). Non-consumers had an additional decline of 1.4 points (P<0.001). An inverse and J-shaped association was observed between the number of cups of coffee consumed and cognitive decline, with the least cognitive decline for three cups of coffee per day (0.6 points). This decline was 4.3 times smaller than the decline of non-consumers (P<0.001).Conclusions:Findings suggest that consuming coffee reduces cognitive decline in elderly men.
This makes sense. Recall my recent post High Caffeine Diets Reduce Heart Risk In Over 65s. Also recall my other related recent post Reduced Blood Flow And Inflammation Precede Alzheimers Put those two together. If something reduces the risk of heart disease it probably improves circulation overall. Well, circulatory problems might well be the root cause of Alzheimer's Disease. If coffee slows the aging of the vascular system then it will reduce both heart disease and Alzheimer's.
Coffee isn't the only candidate for delivering that benefit. Tea and dark chocolate (even more so cocoa powder) have many of the same compounds.
Mars, the makers of Dove chocolates, has just put out a press release describing recent research on the health effects of cocoa. Flavanols in chocolate boost circulation in the brain.
A special cocoa made to retain naturally occurring compounds called flavanols may have the potential to help maintain healthy brain function and chart the course for future research that could lead to new solutions for preventing cognitive decline and dementia, according to a panel of scientists who presented new data at the annual meeting of the American Association for the Advancement of Science (AAAS).
The enhanced brain blood flow from cocoa mentioned below might reduce the odds of developing Alzheimer's disease and other forms of dementia associated with old age.
During the session entitled "The Neurobiology of Chocolate: A Mind- Altering Experience?," a panel of scientists presented evidence from several recent studies that demonstrated the enhanced brain blood flow after study participants consumed a specially formulated flavanol-rich cocoa beverage that was supplied by Mars, Incorporated. One study, conducted by Ian A. Macdonald, PhD, from the University of Nottingham Medical School in the United Kingdom, found that the consumption of this cocoa resulted in regional changes in blood flow in study participants, suggesting that cocoa flavanols may have therapeutic potential for the treatment of vascular impairments within the brain itself.
"Our study showed that acute consumption of this particular flavanol-rich cocoa beverage was associated with increased blood flow to grey matter for 2 to 3 hours," Macdonald said. "This raises the possibility that certain food components like cocoa flavanols may be beneficial in increasing brain blood flow and enhancing brain function among older adults or for others in situations where they may be cognitively impaired, such as fatigue or sleep deprivation."
Mars has their own method of processing cocoa called CocoaPro that retains more of the bioflavonoids found in cocoa. While choosing one brand of chocolate over another might help it is more important to eat cocoa in a form that is least diluted. For example, milk chocolate is most diluted. Dark chocolate is less diluted. Semisweet chocolate is even less diluted. The less sugar and the more cocoa the stronger the dose.
In a January 2007 edition of the American Journal of Clinical Nutrition, A David Smith of University of Oxford surveys recent reports on the health effects of higher folic acid consumption. In a nutshell: Folic acid appears to slow brain aging for those who have lots of B-12 but for those with B-12 deficiency higher folic acid consumption makes the brain decline more rapidly.
Interestingly, Morris et al report both a "good" and a "not-so-good" side of folate. In agreement with current knowledge, they found that a low vitamin B-12 status is associated with macrocytosis, anemia, and cognitive impairment. The key finding in this report concerns interactions between folate status and vitamin B-12 status. The "good news" is that, in subjects with a normal vitamin B-12 status, high serum folate (>59 nmol/L) was associated with protection from cognitive impairment. This finding is remarkable in a population with a much higher mean folate concentration (39 nmol/L) than that seen in countries where there is no mandatory folate fortification. A similar result was reported for Latinos living in California, where higher red blood cell folate concentrations after fortification were associated with protection from cognitive impairment and dementia (11). Simply put, if your vitamin B-12 status is good, folate supplementation is good for you!
So good so far. But there's a gray lining in that silver cloud. Higher folic acid consumption appears to lower cognitive function in those with low B-12 in their blood serum.
The "not-so-good" news from the study by Morris et al is that the relation between high serum folate and cognitive impairment was reversed in subjects who had a low vitamin B-12 status. Those with a low vitamin B-12 status (serum cobalamin <148 pmol/L) and high serum folate (>59 nmol/L) had an odds ratio for cognitive impairment of 5 compared with those whose vitamin B-12 status and folate status were both normal. This group, which had a low vitamin B-12 status and a high serum folate concentration also had an odds ratio close to 5 for anemia. Thus, the simple interpretation is that the cognitive impairment and anemia usually associated with low vitamin B-12 status are made much worse by a high folate status.
This result supports the theory of some nutrition researchers that folic acid supplementation doesn't just mask B-12 deficiency. Folic acid makes the damaging effects of B-12 deficiency worse. One of the effects of B-12 deficiency is neurological damage.
You might think you are not at risk of B-12 deficiency because you eat lots of meat or perhaps you take a B-12 supplement. You might be right. But some people have an impaired ability to absorb B-12. So without a blood test you can't be absolutely sure that your B-12 status is fine.
4% of the elderly in this one study had both high folic acid and low B12.
Morris et al found that {approx}4% of the elderly persons they studied had a combination of low vitamin B-12 status and high folate status. If the same proportion of all elderly persons in the United States is affected, then {approx}1.8 million elderly might be at increased risk of cognitive impairment and anemia because of an imbalance between folate and vitamin B-12.
If you are deficient in B-12 you are at increased risk of neural damage already. The inability to absorb B-12 rises with age. But periodic B-12 injections can restore B-12 levels. So those with B12 deficiency are best off treating their problem with diet and with injections if necessary.
Dr Jane Durga of the University of Wageningen in the Netherlands just published a paper in :Lancet finding late middle age and early elderly people who take daily folic acid have higher performing brains.
Researchers found that men and post-menopausal women aged between 50 and 70 who took daily doses had the mental abilities of those almost five years their junior.
The supplements also helped maintain speed of information processing, reactions involving movement and overall brain power. These abilities decline with age, and their loss has been linked to a higher risk of dementia.
The study, led by Dr. Jose Luchsinger of Columbia University Medical Center in New York, looked at 965 people age 65 and older in Manhattan. Those with higher levels of folate through diet and supplements were less likely to get the devastating brain ailment, the study found.
In an attempt to reduce the incidence of neural tube defects the US Food and Drug Administration mandated the fortification of many grains with folic acid in 1998. But since whole grains used in whole grain breads are not fortified a popular shift toward the use of whole grains and the attempts by many women to reduce carbohydrate consumption to control weight have reduced the concentration of folic acid in the blood of American women since 2000.
Now, it seems, even that first sign of progress is eroding — an apparent victim of dietary shifts, obesity and the stubborn resistance of women in their childbearing years to taking a multivitamin. In a report issued Jan. 5, the CDC found that among women in their childbearing years, blood folate levels had declined 16% by 2004 from the levels recorded in 2000.
The March of Dimes is calling for a doubling of grain folic acid fortification. But as the first article above shows, some scientists are afraid higher folic acid consumption will cause net harm to millions who do not absorb enough B-12.
It might be a good idea to get your blood B-12 tested. If you are deficient then you can change your diet or get a periodic B-12 shot or try taking a B-12 supplement. Once you have enough B-12 then boosting your folic acid is probably a good idea. My advice: Get the folic acid from beans and greens. You'll derive numerous other benefits that way. If you avoid animal products in your diet then get B-12 in a supplement or in highly fortified foods (e.g. Total cereal).
Hate brain aging as much as I do? Eat a few servings of vegetables a day to slow your rate of cognitive decline.
CHICAGO - Eating vegetables, not fruit, helps slow down the rate of cognitive change in older adults, according to a study published in the October 24, 2006, issue of Neurology, the scientific journal of the American Academy of Neurology.
In determining whether there was an association between vegetables, fruit and cognitive decline, researchers from Rush University Medical Center studied 3,718 residents in Chicago, Illinois, who were age 65 and older. Participants completed a food frequency questionnaire and received at least two cognitive tests over a six-year period.
“Compared to people who consumed less than one serving of vegetables a day, people who ate at least 2.8 servings of vegetables a day saw their rate of cognitive change slow by roughly 40 percent, said study author Martha Clare Morris, ScD, associate professor at Rush University Medical Center in Chicago, Illinois. “This decrease is equivalent to about 5 years of younger age.”
Of the different types of vegetables consumed by participants, green leafy vegetables had the strongest association to slowing the rate of cognitive decline. The study also found the older the person, the greater the slowdown in the rate of cognitive decline if that person consumed more than two servings of vegetables a day. Surprisingly, the study found fruit consumption was not associated with cognitive change.
Maybe vitamin E makes vegetables more beneficial for the brain than fruits.
“This was unanticipated and raises several questions,” said Morris. “It may be due to vegetables containing high amounts of vitamin E, which helps lowers the risk of cognitive decline. Vegetables, but not fruits, are also typically consumed with added fats such as salad dressings, and fats increase the absorption of vitamin E. Further study is required to understand why fruit is not associated with cognitive change.”
Then again, maybe other compounds in vegetables protect the brain.
Harvard epidemiologist Meir Stampfer thinks this study was well done.
"This is a sound paper and contributes to our understanding of cognitive decline," said Dr. Meir Stampfer of Harvard's School of Public Health.
"The findings specific for vegetables and not fruit add further credibility that this is not simply a marker of a more healthful lifestyle," said Stampfer, who was not involved in the research.
Some of the commentary about this study answers a curiosity question I've had of late: Most people eat few berries and so population studies on the health effects of fruit consumption do not capture the effects of berry consumption on aging.
Matt Kaeberlein, who conducts research on the biochemical processes of aging at the University of Washington, was surprised the study didn't show any beneficial effect of eating fruit on cognitive decline.
Studies in animals, he said, show that berries—particularly blueberries, strawberries and cranberries—seem to protect memory in aging animals. And a diet high in fruits and vegetables has been linked to protection against heart disease, cancer, stroke, diverticulosis, diabetes and obesity.
Morris agreed that animal research indicates that berries may help preserve memory but that too few people in the study consumed berries regularly to determine if they helped preserve memory and other cognitive functions.
I'm going to keep eating a few bags of dried cranberries every week.
Brain aging is the worst kind of aging. Death of brain cells amounts to the death of part of who you are. Decline in cognitive function is the worst sort of decline in an economy where brain work keeps rising in value while physical work declines in value.
Even worse, brain rejuvenation is going to be the hardest part of body rejuvenation. 20 or 30 years from now if your kidneys or liver or lungs get too old the technology will be available to grow replacements. Or if your heart has lost a lot of muscle cells then stem cell therapies might be able to repair the heart in place. But the brain is a much tougher problem.
The study author Martha Clare Morris above has previously found other dietary factors that influence the rate of brain aging. See my posts Fish In Diet Slows Rate Of Cognitive Decline and Faster Brain Decline With More Fat And Copper In Diets.
Vitamin E is not the only plausible vitamin in green leafy vegetables that might be responsible for the brain protective effects reported above. Also see my post Folic Acid Slows Cognitive Decline With Age. To get lots of folic acid eat greens and beans.
Apple juice and the curcumin in curry might both have protective effects against Alzheimer's Disease.
Want to lower your Alzheimer's risk by 76%?
In a large epidemiological study, researchers found that people who drank three or more servings of fruit and vegetable juices per week had a 76 percent lower risk of developing Alzheimer’s disease than those who drank juice less than once per week.
The study by Qi Dai, M.D., Ph.D., assistant professor of Medicine, and colleagues appears in the September issue of The American Journal of Medicine.
The researchers followed a subset of subjects from a large cross-cultural study of dementia, called the Ni-Hon-Sea Project, which investigated Alzheimer’s disease and vascular dementia in older Japanese populations living in Japan, Hawaii and Seattle, Wash.
For the current study, called the Kame Project, the researchers identified 1,836 dementia-free subjects in the Seattle population and collected information on their dietary consumption of fruit and vegetable juices. They then assessed cognitive function every two years for up to 10 years.
After controlling for possible confounding factors like smoking, education, physical activity and fat intake, the researchers found that those who reported drinking juices three or more times per week were 76 percent less likely to develop signs of Alzheimer’s disease than those who drank less than one serving per week.
The benefit appeared particularly enhanced in subjects who carry the apolipoprotein E ÿ-4 allele, a genetic marker linked to late-onset Alzheimer’s disease – the most common form of the disease, which typically occurs after the age of 65.
A diet that cuts Alzheimer's risk probably cuts stroke and heart disease risk as well.
Researchers have found that vitamins C, E, and beta carotene do not provide a neuroprotective effect against Alzheimer's. Non-Steroidal Anti-Inflammatory Drugs (NSAIDs) also have been found to provide little or no benefit. The researchers behind this study suspected that perhaps polyphenols in foods provide benefit.
Dai began to suspect that another class of antioxidant chemicals, known as polyphenols, could play a role. Polyphenols are non-vitamin antioxidants common in the diet and particularly abundant in teas, juices and wines. Most polyphenols exist primarily in the skins and peels of fruits and vegetables. Recent studies have shown that polyphenols (like resveratrol in wine) extend maximum lifespan by 59 percent and delay age-dependent decay of cognitive performance in animal models.
"Also, animal studies and cell culture studies confirmed that some polyphenols from juices showed a stronger neuroprotective effect than antioxidant vitamins. So we are now looking at polyphenols," Dai said.
The researchers intend to check blood polyphenol levels to see if high polyphenols correlate with low Alzheimer's risk.
The nomenclature here may seem confusing. Catechins in tea are both polyphenols and flavonoids. Polyphenols are a larger set of chemical compounds which includes flavonoids as a subset. Then within the subset called flavonoids exists the smaller subset catechins. Fruits have flavonoids called anthocyanins. Tea and wine (and presumably dark grape juice) contain flavonoids called catechins.
Obvious question: Was the protective effect against Alzheimer's seen in this study due to catechins from tea and grape juice or from anthocyanins found in fruits? Or perhaps from other flavonoids called flavones and flavonols? Or other polyphenols? Or some combination of the above? I'm sorry I do not have an answer for you.
One obvious question: Drink the juice or eat whole fruits and vegetables? Well, juices appear to work (see above) and are quicker to consume. But perhaps the people who consume more fruit and vegetable juices also eat more fruits and vegetables. It is not clear what confounding factors these researchers controlled for.
Writing in the article, Qi Dai, MD, PhD, states, “We found that frequent drinking of fruit and vegetable juices was associated with a substantially decreased risk of Alzheimer’s disease. This inverse association was stronger after adjustments for potential confounding factors, and the association was evident in all strata of selected variables. These findings are new and suggest that fruit and vegetable juices may play an important role in delaying the onset of Alzheimer’s disease”.
I find it really surprising that these researchers could find an influence from juices above the background of all the other factors that will influence polyphenol content of diet.
Enormous amounts of other research has been done on the health benefits of polyphenols including flavonoids. Green tea catechins might reduce the risk of prostate cancer.
Anaheim, Calif. – After a year's oral administration of green tea catechins (GTCs), only one man in a group of 32 at high risk for prostate cancer developed the disease, compared to nine out of 30 in a control, according to a team of Italian researchers from the University of Parma and University of Modena and Reggio Emilia led by Saverio Bettuzzi, Ph.D.
...
The 600 mg-per-day dosage of caffeine-free, total catechins (50 percent of which is EGCG) given to participants in the Italian study is one or two times the amount of green tea consumed daily in China, where ten to 20 cups a day is normal.
I do not want to drink 10, let alone 20, cups of green tea a day. I'd rather take some caffeine-free catechin capsules. Better yet, I'd rather figure out which fruits and vegetables would deliver the same benefits and eat them instead.
Green tea is very popular in Japan and its consumption there might be the cause of lower Alzheimer's in Japanese in Japan as compared to Japanese in America.
Another paper which reported a reduction in blood plasma peroxide free radicals with green tea extract found a higher concentration of catechin polyphenols per cup of green tea.
"We believe we have shown for the first time the course change of both green tea catechin levels in human plasma as well as human plasma lipid peroxide levels after oral green tea catechin supplementation, " said Teruo Miyazawa, Ph.D., biodynamic chemistry professor at the Tohoku University Graduate School of Life Science and Agriculture and the study's principal investigator.
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In the study, 18 healthy male subjects between the ages of 23 and 41 ingested green tea extracts in tablet form (including 254 milligrams of catechins per subject - one cup of green tea contains about 100 to 150 milligrams of catechin). All of the subjects avoided tea and tea-related beverages for 12 hours prior to the testing. Blood samples were taken one hour before and after the catechin ingestion.
I'd love to see a massive comparison study of a wide range of fruits and vegetables, juices, teas, and cocoa (which also contains catechins) where the effects of each food on blood plasma peroxides, blood pressure, and other indicators were compared. What are the most potent foods to eat?
Black tea was found to be the biggest source of catechin polyphenols among elderly Dutch men.
The 806 male participants, averaging age 71 in 1985, were followed until 1995, with complete dietary and medical examinations in 1985 and 1990. Epidemiological evaluation of the health effects of catechins has previously been difficult due to the lack of information on the exact catechin composition of foods. For this study, the authors measured the catechin content of 120 frequently consumed plant foods, using the data to divide the subjects into low, medium and high quintiles of catechin consumption.
Among the men in the highest quintile, 87% of catechins in the diet came from black tea; whereas those in lower quintiles ate more foods in which catechins were less concentrated. High catechin intake was associated with other practices characteristic of a healthy lifestyle, such as refraining from smoking, eating more fruits and vegetables, and increased activity levels.
For examples of more on the health benefits of tea see these research reports: Tea Intake Is Inversely Related to Blood Pressure in Older Women and Black and Green Tea Polyphenols Attenuate Blood Pressure Increases in Stroke-Prone Spontaneously Hypertensive Rats.
Green tea is hardly the only food that can improve blood flow and reduce blood free radicals. For example, see the research paper: Wine Polyphenols Decrease Blood Pressure, Improve NO Vasodilatation, and Induce Gene Expression. The "NO" in the title refers to Nitric Oxide which is a naturally occurring vasodilator (i.e. it makes blood vessels widen which lowers blood pressure). Nitric oxide deficiency is, in all likelihood, a cause of high blood pressure. Some drugs release NO as their mechanism of action. Viagra and Cialis work by releasing NO to cause blood to flow in the right places for male sexual function. Minoxidil, the anti-hair loss drug, has the "nox" in its name because it too is an NO releaser. But better to raise your vascular NO by diet before resorting to drug use. The foods that'll improve NO will also deliver other benefits.
Martha Clare Morris, Sc.D., associated professor at the Institute for Healthy Aging at Rush University Medical Center, and her colleagues assessed the connection between dietary fat and dietary copper intake in 3,718 Chicago residents age 65 years and older. Participants underwent cognitive testing at the beginning of the study, after three years and after six years. An average of one year after the study began, they filled out a questionnaire about their diets. The dietary recommended allowance of copper for adults is .9 milligrams per day. Organ meats, such as liver, and shellfish are the foods with the highest copper levels, followed by nuts, seeds, legumes, whole grains, potatoes, chocolate and some fruits. Copper pipes may also add trace amounts of the metal to drinking water.
Cognitive abilities declined in all participants as they aged. Overall, copper intake was not associated with the rate of this decline. However, among the 604 individuals (16.2 percent of the study group) who consumed the most saturated and trans fats, cognitive function deteriorated more rapidly with the more copper they had in their diets. “The increase in rate for the high-fat consumers whose total copper intake was in the top 20 percent (greater than or equal to 1.6 milligrams per day) was equivalent to 19 more years of age,” the authors write.
This sounds like a stronger argument for reducing saturated and trans fats than for reducing copper in the diet. We already have plenty of reasons to avoid saturated and trans fats. Here's another one.
Here is more evidence for the benefit of fish for reducing the rate of brain aging.
CHICAGO – Consuming fish at least once a week was associated with a 10 percent per year slower rate of cognitive decline in elderly people, according to a new study posted online today from Archives of Neurology, one of the JAMA/Archives journals. The study will be published in the December print edition of the journal.
Martha Clare Morris, ScD, of Rush University Medical Center, and colleagues analyzed six years of data from an ongoing study of Chicago residents, 65 years and older, first interviewed between 1993 and 1997 and every three years in two follow-up interviews. Interviews included four standardized cognitive tests and dietary questions on the frequency of consumption of 139 different foods, as well as questions of daily activities, exercise levels, alcohol consumption and medical history.
Morris found dietary intake of fish was inversely associated with cognitive decline over six years in this older, biracial community study. "The rate of decline was reduced by 10 percent to 13 percent per year among persons who consumed one or more fish meals per week compared with those with less than weekly consumption. The rate reduction is the equivalent of being three to four years younger in age," she said.
The benefit might not be from omega 3 fatty acids.
Although fish is a direct source of omega-3 fatty acids, which have been shown to protect against Alzheimer's disease and stroke, the dietary intake of omega-3 fatty acids was not associated with cognitive change in this study.
In addition, neither consumption of fruit and vegetables nor overall cardiovascular health appeared to account for the study findings, the researchers said.
However, see below for another report that demonstrates a mechanism by which omega 3 fatty acid DHA reduces inflammation and protects brain cells from damage and cell death.
Morris has previously reported that consumption of foods high in vitamin E reduces the incidence of Alzheimer's Diseaes.
Louisiana State University researcher Nicolas G. Bazan has just recently discovered a mechanism by which omega 3 fatty acid DHA protects the brain from neurotoxins and prevents cell death.
Their study shows that docosahexaenoic acid (DHA), an omega-3 fatty acid found in coldwater fish such as mackerel, sardines and salmon, reduces levels of a protein known to cause damaging plaques in the brains of Alzheimer's patients.
What's more, the researchers discovered that a derivative of DHA, which they dubbed "neuroprotectin D1" (NPD1), is made in the human brain. That natural substance plays a key role, too, in protecting the brain from cell death, the study showed.
A time-dependent release of endogenous free DHA followed by NPD1 formation occurs, suggesting that a phospholipase A2 releases the mediator’s precursor. When NPD1 is infused during ischemia-reperfusion or added to RPE cells during oxidative stress, apoptotic DNA damage is down-regulated. NPD1 also up-regulates the anti-apoptotic Bcl-2 proteins Bcl-2 and BclxL and decreases pro-apoptotic Bax and Bad expression. Moreover, NPD1 inhibits oxidative stress-induced caspase-3 activation. NPD1 also inhibits IL-1 -stimulated expression of COX-2. Overall, NPD1 protects cells from oxidative stress-induced apoptosis.
I just decided to have salmon for lunch.
According to a recent report in the American Journal of Clinical Nutrition, folate, a B vitamin found in foods like leafy green vegetables and citrus fruit, may protect against cognitive decline in older adults. The research was conducted by scientists at the Jean Mayer USDA Human Nutrition Research Center on Aging at Tufts University.
A team led by Katherine L. Tucker, PhD, director and professor of the Nutritional Epidemiology Program at the Friedman School of Nutrition Science and Policy at Tufts, studied a group of Boston-area men who were members of the ongoing Normative Aging Study (NAS). Tucker and her colleagues found that men who obtained more folate in their diets showed significantly less of a decline in verbal fluency skills over the course of three years than did men with lower dietary folate intake.
High folate levels, both in the diet and in the blood, also appeared to be protective against declines in another category of cognitive skills known as spatial copying. To test this, the 50- to 85-year-old study participants were asked to copy various shapes and figures, and their drawings were assessed for accuracy. "The men took a series of cognitive tests at the beginning of the study period and then repeated those tests three years later," explained Tucker. "We compared their first and second scores, reviewed their responses to dietary questionnaires, and took blood samples in order to see if nutrient levels in the diet and the blood were related to changes in cognitive performance."
In an earlier study with the same NAS group, which corroborated the findings of other investigators, the Tufts research team observed that high homocysteine--a known blood marker of cardiovascular disease risk--was associated with lower cognitive test scores.
Since folate supplementation can help reduce blood levels of homocysteine, it was thought that this might explain folate's beneficial effects. However, in the current study, the effects of folate were independent of its impact on homocysteine, which turned out to be more strongly associated with tests of memory.
"Unlike our prior work with this population, in which we observed an association between low folate levels and lower cognitive test scores at one point in time, this study looks at the effects of these nutrients over time." Tucker says, "That is an important step in establishing causality."
So low folic acid (a.k.a. folate) causes faster general cognitive decline but high homocysteine causes faster memory decline. Well, vitamins B-12 and B-6 also help keep down homocysteine. A lot of old people have a diminished capacity to absorb B-12. and some even need periodic B-12 shots. High homocysteine is also strongly suspected as a risk factor for cardiovascular disease.
The journal article for this report:
Tucker KL, Qiao N, Scott T, Rosenberg I, Spiro A, III. American Journal of Clinical Nutrition. 2005; 82: 627. "High homocysteine and low B vitamins predict cognitive decline in aging men: the Veterans Affairs Normative Aging Study."