terça-feira, 16 de janeiro de 2018

Could a high-salt diet cause cognitive decline and dementia?


A study in mice found a high-salt diet directly leads to cognitive decline and dementia

A study in mice found a high-salt diet directly leads to cognitive decline and dementia
A new gut-brain connection has been revealed in a study from scientists at Weill Cornell Medicine. The research found that mice fed a high-salt diet directly led to cognitive impairment, dementia, and reduced blood flow in regions of the brain commonly associated with learning and memory.

The study examined mice administered diets with food containing either four or eight percent salt, which equated to between eight and 16 times more salt than a normal healthy diet. These are extremely high levels of salt and only comparable to an extraordinarily high level of human consumption.

The negative results were dramatic, with a 28 percent drop in blood flow in the cortex, and a 25 percent drop in the hippocampus after just eight weeks. The mice on the high-salt diet also performed significantly worse on several behavioral tests, including a maze test, nest building and an object recognition test.

The impaired blood flow in the brain was found to be related to a reduction in the production of nitric oxide, a gas generated by endothelial cells. This reaction to the high-salt diet was shown to be reversible, with cerebral blood flow normalizing four weeks after returning to a regular diet.

Further study homed in on the mechanism that could be causing this response, and it was revealed that it all began with an adaptive immune reaction in the gut. In response to the high salt intake, white blood cells overproduced interleukin 17 (IL-17), a protein known to reduce nitric oxide in endothelial cells.
Perhaps the most intriguing part of the study came when the researchers administered a drug called ROCK inhibitor Y27632 that reduced levels of IL-17 and prevented the reduction in nitric oxide production. The mice responded positively to the treatment, improving in both cognitive tests and behavioral observations.

"The IL-17-ROCK pathway is an exciting target for future research in the causes of cognitive impairment," says Giuseppe Faraco, first author of the study. "It appears to counteract the cerebrovascular and cognitive effects of a high-salt diet, and it also may benefit people with diseases and conditions associated with elevated IL-17 levels, such as multiple sclerosis, rheumatoid arthritis, inflammatory bowel disease and other autoimmune diseases."

Of course, it is worth noting that this study was just in mice, and the levels of salt the animals were fed was extremely high. In humans the only current cognitive impairment known to be caused by salt intake is related to high-blood pressure and hypertension resulting in what is called vascular dementia.

What was notable in this mouse study is that the dementia developed in the animals was irrespective of blood pressure. If these effects do translate to humans then it means that high salt intake could be having a damaging effect on our cognitive abilities that builds over long periods of time.

The study was published in the journal Nature Neuroscience.
Source: Weill Cornell Medicine
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segunda-feira, 15 de janeiro de 2018

Best and worst foods to prevent colon-rectal cancer

Asthma costs the US economy more than $80 billion per year

Asthma costs the U.S. economy more than $80 billion annually in medical expenses, missed work and school days and deaths, according to new research published online in the Annals of the American Thoracic Society.
In "The Economic Burden of Asthma in the United States, 2008-2013," researchers from the Centers for Disease Control and Prevention analyzed data from the Medical Expenditure Panel Survey, the most comprehensive source of data on health care use, expenditures, payment source and health insurance coverage in the U.S.

"The cost of asthma is one of the most important measures of the burden of the disease," said Tursynbek Nurmagambetov, PhD, lead study author and health economist at the Centers for Disease Control and Prevention. "Cost studies can influence health policy decisions and help decision makers understand the scale, seriousness and implications of asthma, so that resources can be identified to improve disease management and reduce the burden of asthma."

Of 213,994 respondents to the survey over a six-year period, the study identified 10,237 people with treated asthma. The researchers defined treated asthma as having at least one medical encounter for asthma or having a prescription for at least one asthma medicine filled during a calendar year. Based on the pooled sample, researchers estimated average annual numbers and costs for the U.S. population.
Based on the 2008-2013 pooled sample, the study estimated (all costs are expressed in 2015 U.S. dollars):
  • About 15.4 million people in the U.S. had treated asthma each year.
  • The total annual cost of asthma in the U.S., including medical care, absenteeism and mortality, was $81.9 billion.
  • The annual per-person medical cost of asthma was $3,266. Of that, $1,830 was for prescriptions, $640 for office visits, $529 for hospitalizations, $176 for hospital outpatient visits and $105 for emergency room care.
  • Asthma-related mortality cost $29 billion per year, representing on average 3,168 deaths.
  • Missed work and school days combined cost $3 billion per year, representing 8.7 million workdays and 5.2 million school days lost due to asthma.
  • People with no health insurance had significantly lower per person total medical expenditure for asthma compared to insured people.
According to the authors, the study likely underestimated the total cost of asthma to the U.S. economy because their analysis did not include people whose asthma went untreated. The study also did not include nonmedical costs associated with asthma, including transportation expenses, time lost waiting for appointments and diminished productivity while functioning at work or school with asthma.

"The findings of the paper highlight the critical need to support and further strengthen asthma control strategies," Dr. Nurmagambetov said. "CDC's National Asthma Control Program was founded in 1999 to help reduce the burden of asthma in the United States. In order to reduce asthma-related ER visits, hospitalizations, absenteeism and mortality, we need to support guidelines-based care, expand self-management education and reduce environmental asthma triggers at homes."

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domingo, 14 de janeiro de 2018

New warning system discovered in the immune defense

Researchers at Linköping University in Sweden have discovered a previously unknown warning system that contributes to the body's immune system. Mitochondria in the white blood cells secrete a web of DNA fibres that raises the alarm. The results have been published in the scientific journal PNAS, and may lead to increased knowledge about autoinflammatory diseases and cancer.

White blood cells are major components of the body's immune defence, and the research group has shown that several types of these cells react against small DNA fragments that are similar to the DNA from bacteria and viruses. The white blood cells spray out a web consisting of mitochondrial DNA (mtDNA) strands. Mitochondria are present in all cells and normally produce the energy needed by the cell, by burning sugar and fat to form water and carbon dioxide.

The web that the mitochondria release sends signals to the surrounding cells that the body is under attack, and cause other white blood cells to release a signal substance known as "interferon type 1." This substance helps the immune system to combat the infection.
Previous studies have shown that the level of mtDNA in the blood can be elevated after certain inflammatory diseases and after some surgical traumas.

"We show that the white blood cells in the immune system can release mtDNA outside the cells in an active process in response to infectious agents such as bacteria and viruses. The discovery raises the possibility of further studies in which we will try to reduce the release of mtDNA, and in this way reduce the inflammation that it causes," explains Björn Ingelsson, researcher and associate lecturer at the Department of Clinical and Experimental Medicine at Linköping University. He has conducted the research together with Professor Emeritus Anders Rosén and other co-workers.

Other types of web formed by white blood cells in the immune system (known as "neutrophils") have been previously known. These cells release meshes coated with antibacterial proteins. However, the formation of the newly discovered mtDNA webs differs fundamentally from that of the other types of web. The researchers have shown that the mtDNA webs are activated within a couple of minutes, which is faster than the neutrophil-based meshes. The latter also lack the signal function that the mtDNA webs have. Further, the mtDNA webs survive in the blood longer before being dissolved.
But surely this is a positive process in which the immune defence works to remove the intruding bacteria or viruses?

"Well, of course it's positive that the defence mechanisms are activated. But remember that you can have too much of a good thing. If an unintentional secretion of mtDNA occurs, or if the secreted mtDNA is not removed from the blood, undesired inflammation may occur, and it is this side-effect we want to prevent," says Björn Ingelsson.
High levels of interferon type 1, the signal substance activated by the mtDNA webs, occur in several autoimmune diseases and several types of cancer. The researchers believe that it may be possible to quantify the secreted mtDNA molecules and interpret the warning signals, and in this way understand these diseases better.
The research has been financed with support from Linköping Medical Society, Linköping University, Region Östergötland, the Ingrid Asp Foundation and the Swedish Cancer Society.

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Taking loads of vitamin B could increase your risk of lung cancer

Specifically, the study found that taking high doses of B6 (20 milligrams or more per day averaged over a period of 10 years) increased the likelihood that male smokers would develop lung cancer by more than 30 percent above an already high risk. Taking 55 micrograms of B12 a day, also averaged over a period of 10 years, increased the likelihood that male smokers would develop lung cancer by more than 40 percent. Smoking is the leading cause of lung cancer, so if the study’s results hold up to further scrutiny, popping mega doses of B6 and B12 may be like pouring gasoline on a fire.

The men most likely to increase their risk of lung cancer were consuming a lot more vitamin B6 and B12 than you'd find in your typical multivitamin. Multivitamins typically only contain the Recommended Dietary Allowance (RDA), a rough estimate of how much the average American needs to consume to ward off a vitamin deficiency. But the men who showed the greatest increased risk for lung cancer were exceeding the RDA by a lot—15 times more than the RDA for vitamin B6; 20 times more than the RDA for vitamin B12. And while B vitamins are important in helping the body make new DNA and repair existing DNA, they also interact with the pathway that allows lung cancer to spread.

“When you disrupt this pathway, it stands to reason that there can be consequences,” says lead author Theodore Brasky, a researcher at The Ohio State University Comprehensive Cancer Center.
For a long time, the consequences researchers focused on were the health risks associated with too few B vitamins, not too many. A lack of folic acid (vitamin B9) in pregnant women, for example, is associated with poor neurological development of the fetus. There wasn’t much concern that we would over-consume B vitamins. Unlike, say, vitamin A or vitamin D—which both get stored in our fat and can lead to dangerous overdoses—B vitamins are water soluble. Under the worst-case scenario, many researchers thought, vitamin popping Americans were simply peeing away their paychecks.

That theory began to change when studies released in 2009 and 2010, including one clinical trial, suggested that B vitamins had a potential for harm—especially when it comes to lung cancer. But the results of those studies weren’t consistent. The clinical trial originally set out to determine the impact of vitamins B6, B9 and B12, both alone and in combination, on heart disease—not lung cancer. It was only when the researchers analyzed the long-term data that they spotted an increased likelihood of lung cancer in patients consuming B9 and B12 together. The researchers didn't separate out men and women, and they couldn't go back to determine whether B9, B12, or the combination of the two was to blame. But those studies inspired Brasky and his colleagues to pull data from the SEER cancer registryfor more information.

The SEER (Surveillance, Epidemiology, and End Results) database, which began in 1973, collects and publishes data related to cancer incidence and survival from people based across the United States. As part of the program, participants answer detailed information about diet, health and lifestyle. Brasky and his colleagues drew on data from the VITamins and Lifestyle (VITAL) Study, which is specifically designed to look at the role—good or bad—that supplements play in determining cancer risk.

“It was designed exactly to answer these questions,” says Brasky.
VITAL participants fill out questionnaires that delve deeply into their dietary supplement habits, including multivitamins, minerals (like calcium and magnesium), and non-vitamin, non-mineral supplements like black cohosh, ginseng, or gingko biloba. They're also asked questions about dosing, allowing the study to average daily intake over 10 years. So, if a participant took a multivitamin with 10 micrograms of B6 per day, but they’d only taken it for a year, this would be represented as an average of 1 microgram per day in the study.

Multivitamins were not associated with risk, but individual supplements—which tend to be sold at levels much higher than RDA—were. Higher doses of Vitamins B6 and B12 seemed to be correlated with an increased risk of lung cancer among men who smoke.
There are some caveats. The first is that the study only looked at individuals between the ages of 50 and 76, which means we don’t know if the effects replicate in younger people. This is also an observational study—participants had to report their own habits, so we have to consider that they might have over- or underestimated their supplement usage. And while there are eight B Vitamins—B1 (Thiamine), B2 (Riboflavin), B3 (Niacin), B5 (Pantothenic acid), B6 (Pyridoxine), B7 (Biotin), B9 (Folic Acid), and B12 (Cobalamin)—the study only found risks associated with individual supplements of B6 and B12, and even then, that risk was exclusively in men who smoke. There was no association found in non-smokers, former smokers, men who only consumed vitamins B12 and B6 in the lower doses of a multivitamin, or in women.

This isn’t the first study to find that the lung cancer risks of vitamin B12 are unevenly distributed. An earlier study also found a subtle but present increase in lung cancer risk with high consumption of B12, based on blood serum levels of the vitamin. When the researchers broke apart the data by gender, they found that the risk was actually only present in men.

“If we had to put out a guess, sex hormones are important in the regulation of the same pathway,” says Brasky. “The way I see it, either having estrogen is good and protective, or having more testosterone is harmful. Men seem to have a higher risk.”
It’s dangerous to alter one’s behavior based on the strength of a single study. And Brasky’s study, while intriguing, is not conclusive. And even if you take the results to heart, the findings don't really suggest you should stop taking B12. Quitting smoking would be the better course of action.

That said, unless you’re deficient—people with Crohn’s disease, celiac disease, vegans, and the elderly are especially at risk—most of us simply don’t need to take vitamin B supplements. And as this study and others suggest, the fact that something is water soluble (and not immediately toxic) doesn't mean it can't hurt us in some insidious way. So the supplements you take because you'd rather be safe than sorry might do more than give you very expensive pee. They might actually be making you sick.

sábado, 13 de janeiro de 2018

3 Daily Habits That Will Change Your Life

It's not the big things that take out most leaders and creative pros, it's the little ones. Over time, they forget to do the small things that position them to bring their best effort to the table every day. While everything might look fine to those around them, the decay has already begun and they are on the path of slow decline.

As author Gretchen Rubin wrote, "What you do every day matters more than what you do once in a while." Without a set of daily practices to keep you aligned and energized, your talents will eventually fail you.
While there are many practices that you can implement to help you stay at the top of your game, there are a few "keystone practices" that can pull your creative world together and set you up to be prolific, brilliant, and healthy.

Daily Study

You can't draw water from an empty well. Do you take time each day to fill yours? The quality of input that you curate often determines the quality of your creative output. As Steve Jobs once quipped, "creativity is just connecting things", but to do so you obviously need things to connect.

I encourage you to set aside time each morning or evening to fill your well, to read inspiring or challenging books, to watch videos or listen to talks, or to otherwise fill your well so that you have something to draw from when engaging in your work.

Reflection and Journaling

It's not enough to simply absorb a lot of stimuli. If you're not taking the time to make connections and consider how those stimuli might apply to your life and work, they will be quickly forgotten. Take fifteen minutes at some point during your day - preferably right after your study time - to reflect on how what you're learning and seeing might apply to the projects you're working on. Reflect on any patterns that you're noticing. Consider how different things you're reading - even across disciplines - might apply to each other. Often the best ideas result from "crossing the streams."

One exercise that has been tremendously helpful in my life (and the lives of many creative people I've interviewed) is known as Morning Pages, which is a practice prescribed by Julia Cameron in her book The Artist's Way. Essentially, it consists of free-writing three pages of stream of consciousness thought as your very first act of the day. It's not journaling, it's just free-writing. The objective is to get all of the chatter out of your brain before you begin the day so that it isn't clogging the works and preventing you from thinking clearly.

A Daily Walk

Finally, consider getting out of your office once a day for a short walk. It's not only good for your health to move around a bit, but it's also good for your creative productivity. The variety of stimuli that you'll encounter will often jog new insights, and the break from "the grind" will allow your mind to form patterns out of loose connections that are often overlooked in the hustle of your workspace.
Whatever they are, make sure that you have a set of practices to ground you and help you maintain stability in the midst of uncertainty. The infrastructure you build is into your day is what will sustain you when life and work are stretching you beyond your limits.

3 steps to happiness, according to a Buddhist monk

Matthieu Ricard is not someone who uses spirituality as a way to get famous — in fact, learning to accept the fame that's been given to him and use it as an opportunity for good was turning point.
Ricard, 71, is a Tibetan Buddhist monk who moved to the Himalayas from France in his 20s and became a monk at age 30. His first got the media's attention in 1997 when he co-authored a book with his father Jean-François, a renowned philosopher. Since then, he's given two TED Talks that went viral online, and written multiple bestsellers. He gives his share of any of his projects' proceeds to his charity, Karuna-Shechen, which provides health care and educational services to underserved communities in India, Nepal, and Tibet.

The media has been fond of calling Ricard "the happiest man alive," a title Ricard tries to discourage, after Ricard's gamma brain waves were measured to be the strongest in a 2000 University of Wisconsin study.
He's also a confidante of the Dalai Lama, and serves as his French translator.

I recently had a chance to speak with Ricard for Business Insider's podcast "Success! How I Did It," around the release of his latest book, "Beyond the Self."
And though we discussed the arc of his life, he also shared lessons that particularly resonated with me.

There are two types of success

While Ricard now spends most of his time in isolation, he was born to famous socialites, a writer and a painter, who held parties with the likes of the composer Igor Stravinsky and photographer Henri Cartier-Bresson.

Even at a young age he could tell that all of the indicators of external success — influence, respect, wealth — were not always accompanied by happiness. When he devoted his life to Buddhism as a young man, he realized that happiness is a skill, a honed way of viewing the world, that does not automatically accompany the trappings of this external success.

Ricard said that he instead prefers the type of success he calls "personal flourishing," which is "fulfilling my deepest aspiration."
And by "deepest aspiration," he means something much more existential than aspiring to a big paycheck or lavish home. He's referring to a success defined by self-fulfillment for the purpose of positively affecting others. "So to transform yourself to serve others," he said.

It is sometimes the most rational choice to trust your intuition

"Go with your gut," sounds like reckless, foolish advice. But one of Ricard's stories made me realize there are times to trust your intuition.
As a young man, Ricard studied molecular genetics under a Nobel laureate at the prestigious Pasteur Institute. He would take breaks from his studies to pursue his growing interest in Buddhism, and traveled to Darjeeling to learn from spiritual masters. Ricard ultimately received his PhD, but when it came time to decide what to do with his life, the decision was easy.

"It was not at all a hard decision," Ricard said, of his choice to begin a path to monkhood. "I never had any agitation." He compared it to fruit that has ripened on a tree: "At some point you don't have to pull and break the branch to get the fruit. It's just touch it and it falls in your hands."

He had given himself plenty of time throughout his travels back and forth between India and France to decide what felt right to him, and when it was time, he didn't make a list of pros and cons for each option — he followed his heart and acted without hesitation. Ricard said that since that point, he has made every major decision in his life the same way.

It is necessary to accept what you cannot change

Ricard wrote the book "The Monk and the Philosopher" primarily as a bonding experience with his aging father. But when the attention followed, he decided to follow the Dalai Lama's example and use celebrity as a way to spread lessons about happiness and fulfillment.

Then, after the Independent covered the findings of the meditation study Ricard participated in, they named him "the happiest man in the world" in 2007. No matter how many times Ricard objected, the phrase kept appearing in outlets around the world.
The title came up when Ricard was with one of his teachers, and he said his teacher told him, "Just leave. Make use of it for a good purpose, for the human project." That is, if people insist on calling him "the happiest man in the world," then use that opportunity to teach them how to be happier.

Experts raise concerns over raw meat diets for cats and dogs

Experts are warning dog and cat owners to be aware of the risks associated with feeding their pets raw meat-based diets (RMBDs), instead of the more conventional dry or canned pet foods.
In the Vet Record today, a team of researchers based in The Netherlands say these diets may be contaminated with bacteria and parasites, and as such may pose a risk to both animal and human health.

Feeding RMBDs to companion animals has become increasingly popular across the world, yet claims of health benefits are not backed by evidence, and several studies have reported possible risks.
Of most concern, however, is the risk to public or animal health due to contamination of RMBDs with zoonotic bacteria and parasites, that can pass between animals and humans.
So a team led by Paul Overgaauw at Utrecht University set out to determine the presence of four zoonotic bacteria and two parasite species in commercial RMBDs, available in most pet shops and supermarkets.

They analysed 35 commercial frozen RMBDs from eight different brands, widely available in The Netherlands. Escherichia coli O157 was isolated from eight products (23%), Listeria species were present in 15 products (43%) and Salmonella species in seven products (20%). Both E coli O157 and Salmonella infections in humans have been linked with serious illnesses.

Four products (11%) contained the parasite Sarcocystis cruzi and another four contained Sarcocystis tenella. In two products (6%) Toxoplasma gondii was found. The Sarcocystes species are not zoonotic but pose a risk to farm animals. T gondii is an important zoonosis with a high disease burden in humans.
"Despite the relatively low sample size of frozen products in our study, it is clear that commercial RMBDs may be contaminated with a variety of zoonotic bacterial and parasitic pathogens that may be a possible source of bacterial infections in pet animals and if transmitted pose a risk for human beings," say the researchers.

"Cats and dogs that eat raw meat diets are also more likely to become infected with antibiotic-resistant bacteria than animals on conventional diets, which could pose a serious risk to both animal health and public health," they add.

They outline several ways in which pet owners and other household members can encounter such pathogens. For example, through direct contact with the food or with an infected pet; through contact with contaminated household surfaces; or by eating cross-contaminated human food.

They therefore suggest that pet owners should be informed about the risks associated with feeding their animals RMBDs, and should be educated about personal hygiene and proper handling of RMBDs.
Warnings and handling instructions should also be included on product labels and/or packages, they advise.

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Higher stress among minority and low-income populations can lead to health disparities

People with low incomes and racial/ethnic minority populations experience greater levels of stress than their more affluent, white counterparts, which can lead to significant disparities in both mental and physical health that ultimately affect life expectancy, according to a report from the American Psychological Association.

"Good health is not equally distributed. Socio-economic status, race and ethnicity affect health status and are associated with substantial disparities in health outcomes across the lifespan," said Elizabeth Brondolo, PhD, chair of an APA working group that wrote the report. "And stress is one of the top 10 social determinants of health inequities."

Stress-related illnesses and injuries are estimated to cost the United States more than $300 billion per year from accidents, absenteeism, employee turnover, lowered productivity and direct medical, legal and insurance costs, according to the report.
People with lower incomes report more severe (but not more frequent) stress and having had more traumatic events in their childhood, said the report. African-Americans and U.S.-born Hispanics also report more stress than their non-Hispanic white counterparts, stemming in part from exposure to discrimination and a tendency to experience more violent traumatic events.

And all that stress can lead to mental and physical health problems.
"Stress affects how we perceive and react to the outside world," Brondolo said. "Low socio-economic status has been associated with negative thinking about oneself and the outside world, including low self-esteem, distrust of the intentions of others and the perceptions that the world is a threatening place and life has little meaning. Stress is also known to contribute to depression."
Stress may also play a role in physical health disparities by affecting behavior. High levels of stress have been consistently associated with a wide variety of negative health behaviors, including smoking, drinking, drug use and physical inactivity. These behaviors and their outcomes (e.g., obesity) are closely linked to the onset and course of many diseases, including diabetes, cancer, cardiovascular disease and cognitive decline later in life, according to the report.

A 2016 analysis indicated that men whose income is in the top 1 percent live almost 15 years longer than those in the bottom 1 percent, according to the report. For women, that difference is almost 10 years.
A number of interventions at the individual, family, health care provider and community levels that could be useful in helping to ameliorate the negative effects of stress on low-income and minority populations and potentially address some of the health disparities are identified in the report. For instance, at the individual level, mind-body interventions, such as yoga or meditation, were found to be accepted by disadvantaged groups and showed some effectiveness at improving mental and physical health outcomes. Other interventions cited included improving the quality of communication between patients and their health care providers and teaching parenting skills to promote positive parent-child attachments.

The report concludes with a series of recommendations, including calling for additional multidisciplinary research on the interrelationship of barriers to health experienced by disadvantaged individuals. It also recommends improving psychology training programs to make sure clinicians are capable of adequately discussing and addressing the effects of inequality on individual health. Increasing awareness among the public and policymakers on the stress-inducing implications of persistent exposure to implicit biases and microaggressions is also important, according to the report.

"Disparities in both stress and health may not be visible to those who have more advantages or who have relatively limited direct contact with those affected," said Brondolo. "A well-informed community is critical to improving the health of racial/ethnic and poor communities."