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Published on Leave a comment on Vitamin B12 and the Aging Brain

Another piece of the puzzle on how the brain ages. Vitamin B12 is important for brain health, and higher levels are associated with slower rates of brain changes associated with aging. And the opposite is true with homocysteine levels - increased levels are associated with faster rates of brain changes that are associated with aging (such as higher rates of total brain tissue volume loss). Keep in mind that these effects were modest, but this also raises the question of whether long-term B12 supplementation would benefit everyone or only those with a deficiency? From Medscape:

Vitamin B12 May Slow Brain Aging

Individuals with increased levels of circulating homocysteine have faster rates of brain changes associated with aging than other people, whereas higher levels of vitamin B12 are associated with slower rates of brain aging, new research suggests.

Babak Hooshmand, MD, PhD, Center for Alzheimer Research–Aging Research Center, Karolinska Institutet, Stockholm, Sweden, and colleagues found that total brain volume losses were lower in individuals with higher baseline vitamin B12 levels, whereas the opposite was true of those with increased homocysteine levels.

"Vitamin B12 and tHcy [total homocysteine] might be independent predictors of markers of brain aging in elderly individuals without dementia," the investigators write. They add, "[I]f the association is causal, supplementation with B vitamins may be effective for prevention of brain damage due to increased levels of total homocysteine. Adequately timed and powered randomized clinical trials are needed to determine efficient treatment guidelines." The research was published online April 27 in JAMA Psychiatry.

The researchers examined data on 501 participants aged 60 years and older from the Swedish National Study on Aging and Care, in Kungsholmen. All participants were free of dementia at baseline. Of these, 299 underwent repeated structural brain MRI between 2001 and 2009....Venous blood samples were collected at baseline, from which circulating levels of vitamin B12, red blood cell folate, and sulfur amino acids were determined. These were correlated with changes in brain tissue volumes and total white matter hyperintensity (WMH) over 6 years.

He also pointed to the single-center, randomized VITACOG study, in which 271 individuals older than 70 years who had mild cognitive impairment received supplementation with high-dose folic acid and vitamins B6 and B12. "They lost less brain compared to people who had normal homocysteine and normal vitamin levels, meaning that those with high levels of homocysteine or with clinical or biochemical vitamin deficiency can benefit from supplementation," said Dr Hooshmand.

Published on Leave a comment on Increase Fruit Intake During Pregnancy and Boost Baby’s Cognitive Development?

Increasing fruit and fruit juice consumption during pregnancy leads to better cognitive development in babies? New research found that six or seven servings of fruit or fruit juice a day prenatally was associated with 6 or 7 points higher IQ at one year of age. Interestingly, fruit flies show a similar effect. But postnatal (after birth) fruit intake did not enhance cognitive outcomes in human babies or Drosophila fruit flies. But now, will these results in the babies hold up over time?

The US Department of Agriculture (USDA) and US Department of Health and Human Services recommend 2 cups (3–4 servings) of fruit per day for active women. One cup of fruit (2 servings) consists of either 1 cup of raw or cooked fruit, 1 cup (8 oz) of 100% fruit juice, or a small whole fruit. Note that the results of the study support an increased consumption of fruit to 6–7 servings or 3 cups per day for pregnant women.From Science Daily:

Prenatal fruit consumption boosts babies' cognitive development

The benefits of eating fruit can begin as early as in the womb....The study, published in the journal EbioMedicine, found that mothers who consumed more fruit during pregnancy gave birth to children who performed better on developmental testing at one year of age. Piush Mandhane, senior author of the paper and associate professor of pediatrics at the University of Alberta's Faculty of Medicine & Dentistry, made the discovery using data from the Canadian Healthy Infant Longitudinal Development (CHILD) Study--a nationwide birth cohort study involving over 3,500 Canadian infants and their families.

"We wanted to know if we could identify what factors affect cognitive development," Mandhane explains. "We found that one of the biggest predictors of cognitive development was how much fruit moms consumed during pregnancy. The more fruit moms had, the higher their child's cognitive development."

The study examined data from 688 Edmonton children, and controlled for factors that would normally affect a child's learning and development such as family income, paternal and maternal education, and the gestational age of the child. Using a traditional IQ scale as a model, the average IQ is 100 and the standard deviation is 15; two thirds of the population will fall between 85 and 115. Mandhane's study showed that if pregnant mothers ate six or seven servings of fruit or fruit juice a day, on average their infants placed six or seven points higher on the scale at one year of age.

To further build on the research, Mandhane teamed with Francois Bolduc, an associate professor in the Faculty of Medicine & Dentistry's Division of Pediatric Neurology, who researches the genetic basis of cognition in humans and fruit flies....."Flies are very different from humans but, surprisingly, they have 85 per cent of the genes involved in human brain function, making them a great model to study the genetics of memory," says Bolduc....In a subsequent series of experiments, he showed that flies born after being fed increased prenatal fruit juice had significantly better memory ability, similar to the results shown by Mandhane with one-year-old infants. He believes it suggests that brain function affected by fruit and the mechanisms involved have been maintained through evolution, and conserved across species.

Published on Leave a comment on Exercise As Anticancer Therapy?

We've all heard of immunotherapy as a possible future treatment for many cancers, but other possible treatments are also being tested. Two possibilities caught my eye.

The first study is looking at exercise for advanced prostate cancer - to extend life, and the other is testing a vaccine for those with prostate cancer who haven't yet treated it (they've just been doing "active surveillance" instead).  And since the studies are occurring now, and people are still joining, then the results are still unknown and won't be known for years.

But one can hope.... Exercise as anticancer therapy? A vaccine after cancer diagnosis?

From Medical Xpress: Exercise, future anticancer therapy?

At age 70, Alfred Roberts plays hockey twice a week. Nothing special, right? Except that for three years he has had advanced prostate cancer, which has spread to his bones. "I've always been active. Hockey keeps me in shape and keeps my mind off things. I've got friends that have played until age 80, and my goal is to beat them!" said the veteran stick handler.

Several studies have demonstrated the benefits of exercise to improve the quality of life of people with cancer. But Dr. Fred Saad, urologist-oncologist and researcher at the University of Montreal Hospital Research Centre (CRCHUM), goes further. He believes that physical exercise has a direct effect on cancer, as effective as drugs, for treating patients with prostate cancer, even in advanced stages of the disease.

"Typical patients with metastases often become sedentary. It is thought that this affects cancer progression," he said. Together with Robert Newton, professor at the Edith Cowan University Exercise Medicine Research Institute in Australia, Dr. Saad is leading the first international study which aims to demonstrate that exercise literally extends the life of patients with metastatic prostate cancer....In the coming weeks, some sixty hospitals across the world will begin recruiting patients. In total, nearly 900 men with advanced prostate cancer will participate.

"We will study exercise as if it were a drug added to standard treatments. All patients will be treated within the latest scientific knowledge for this type of cancer. They will continue to follow their therapies and take their medications. But half of the patients will receive psychosocial support with general recommendations on physical exercise. The other half will also follow a high intensity exercise program," he explained.

The exercise medicine expert Professor Robert Newton has designed a specific strength and cardiovascular training program for patients in the "exercise" group. "They will have an hour of aerobic and resistance training three times a week. An exercise specialist will supervise them for the first 12 months, and then they will continue without direct supervision. We will evaluate quality of life, appetite, and treatment tolerance in relation to their improved physical condition," said Professor Newton, who is co-director of the Edith Cowan University, Exercise Medicine Research Institute.

The hypothesis is that exercise has a direct impact on cancer progression in addition to helping patients better tolerate therapy. Ultimately, they will live longer. The results of this large study, which involves some one hundred researchers in Canada, the US, Australia, Ireland, the Netherlands, and the UK, will not be known for five years. Could the findings be extended to other types of cancer? It is too early to tell, but researchers are betting that exercise could well become the next anticancer therapy. Alfred Roberts is also convinced that exercise helps defy the odds: "As long as I can skate, I'll play hockey!"

From Medscape:  A Treatment Vaccine for Low-Risk Prostate Cancer

A Louisiana-based biopharmaceutical company is betting that its experimental immunotherapeutic vaccine can keep previously untreated prostate cancer in check. The company, OncBioMune Pharnaceuticals, Inc, in Baton Rouge, is planning to test the vaccine, dubbed ProscaVax, in a phase 2 trial for patients with previously untreated prostate cancer and in a second trial for patients with recurrent or hormone-refractory disease. The trial of a treatment vaccine in untreated, low-risk prostate cancer patients is novel.

Published on Leave a comment on Avoid Triclosan For Your Gut Health?

Try to avoid triclosan. Read labels (especially soaps, personal care, and household cleaning products) and avoid anything that says it contains triclosan, or is anti-bacterial, anti-fungal, anti-microbial, or anti-odor. We easily absorb triclosan into our bodies, and it has been detected in our urine, blood, and breast milk. Among its many negative effects (e.g., here and here) is that it is now linked to disruption of gut bacteria.

The gut microbiome performs vital functions in our bodies. Deviation from the normal microbiome (our microbial communities being out of whack) is known as dysbiosis. Dysbiosis has been associated with human diseases, including diabetes, heart disease, arthritis, and malnutrition. The researchers used zebrafish because they are commonly used to study impacts of various chemicals on gut microbial communities. So yes, the findings are valid and match what other studies have found. So please try to avoid triclosan. From Science Daily:

Common antimicrobial agent rapidly disrupts gut bacteria

A new study suggests that triclosan, an antimicrobial and antifungal agent found in many consumer products ranging from hand soaps to toys and even toothpaste, can rapidly disrupt bacterial communities found in the gut.The research was published in PLOS ONE by scientists from Oregon State University. It was based on findings made with zebrafish, which researchers believe are an important animal model to help determine possible human biological and health impacts of this antimicrobial compound.

Triclosan was first used as a hospital scrub in the 1970s and now is one of the most common antimicrobial agents in the world, found in shampoos, deodorants, toothpastes, mouth washes, kitchen utensils, cutting boards, toys, bedding, socks and trash bags. It continues to be used in medical settings, and can be easily absorbed through the skin.

"However, there's now a growing awareness of the importance of the bacteria in our gut microbiome for human health, and the overuse of antibiotics that can lead to the rise of 'superbugs.' There are consequences to constantly trying to kill the bacteria in the world around us, aspects we're just beginning to understand."

In the new study, researchers found that triclosan exposure caused rapid changes in both the diversity and composition of the microbiome in the laboratory animals. It's not clear what the implication may be for animal or human health, but scientists believe that compromising of the bacteria in the intestinal tract may contribute to the development or severity of disease. Some bacteria were more susceptible to the impact of triclosan than others, such as the family Enterobacteriaceae; and others were more resilient, such as the genus Pseudomonas.

The gut-associated microbiome performs vital functions for human health, prevents colonization with pathogens, stimulates the development of the immune system, and produces micronutrients needed by the host. Dysfunction of this microbiome has been associated with human disease, including diabetes, heart disease, arthritis and malnutrition, the scientists pointed out in their study.

Triclosan has been a concern in part because it is so widely used, and it's also readily absorbed through the skin and gastrointestinal tracts, showing up in urine, feces and breast milk. It also has been associated with endocrine disruption in fish and rats, may act as a liver tumor promoter, and can alter inflammatory responses.

Published on Leave a comment on Can A Healthy Lifestyle Prevent Cancer?

Another new study about lifestyle and the risk of cancer. Many earlier studies have established some lifestyle factors that increase cancer risk: smoking, alcohol use, obesity, and physical inactivity. In this study the researchers found that about 20% to 40% of cancer cases and about half of cancer deaths can be potentially prevented through lifestyle modification.

For some cancers the the effect is even larger - for example, approximately 80% to 90% of lung cancer deaths could be avoided if Americans adopted the lifestyle of the low-risk group, mainly by quitting smoking. For other cancers, from 10% to 70% of deaths could be prevented. Bottom line: making some lifestyle changes could change a person's cancer risk.

From Science Daily: Can a healthy lifestyle prevent cancer?

A large proportion of cancer cases and deaths among U.S. individuals who are white might be prevented if people quit smoking, avoided heavy drinking, maintained a BMI between 18.5 and 27.5, and got moderate weekly exercise for at least 150 minutes or vigorous exercise for at least 75 minutes, according to a new study published online by JAMA Oncology. Cancer is a leading cause of death in the United States.

Mingyang Song, M.D., Sc.D., of Massachusetts General Hospital, Harvard Medical School and the Harvard T.H. Chan School of Public Health, Boston, and Edward Giovannucci, M.D., Sc.D., of the Harvard T.H. Chan School of Public Health and Harvard Medical School, Boston, analyzed data from two study groups of white individuals to examine the associations between a "healthy lifestyle pattern" and cancer incidence and death.

A "healthy lifestyle pattern" was defined as never or past smoking; no or moderate drinking of alcohol (one or less drink a day for women, two or less drinks a day for men); BMI of at least 18.5 but lower than 27.5; and weekly aerobic physical activity of at least 150 minutes moderate intensity or 75 minutes vigorous intensity. Individuals who met all four criteria were considered low risk and everyone else was high risk. The study included 89,571 women and 46,399 men; 16,531 women and 11,731 had a healthy lifestyle pattern (low-risk group) and the remaining 73,040 women and 34,608 men were high risk.

The authors suggest about 20 percent to 40 percent of cancer cases and about half of cancer deaths could potentially be prevented through modifications to adopt the healthy lifestyle pattern of the low-risk group.The authors note that including only white individuals in their PAR estimates may not be generalizable to other ethnic groups but the factors they considered have been established as risk factors in diverse ethnic groups too.

Published on Leave a comment on Get Active and Lower Risk of Developing Cancer

A recent study pooled the data from over a million Europeans and Americans and found that higher levels of leisure-time physical activity was associated with a reduced risk of developing cancer in 13 of the 26 cancers looked at.

For that group of 13 cancers, the cancer risk reduction ranged from 10% to 42%. And most of these associations (leisure-time physical activity and lower risk of cancer) were evident regardless of body size or smoking history. Bottom line: getting active may lower your cancer risk.

From Science Daily: Physical activity associated with lower risk for many cancers

Higher levels of leisure-time physical activity were associated with lower risks for 13 types of cancers, according to a new study published online by JAMA Internal Medicine. Physical inactivity is common, with an estimated 51 percent of people in the United States and 31 percent of people worldwide not meeting recommended physical activity levels. Any decrease in cancer risk associated with physical activity could be relevant to public health and cancer prevention efforts.

Steven C. Moore, Ph.D., M.P.H., of the National Cancer Institute, Bethesda, Md., and coauthors pooled data from 12 U.S. and European cohorts (groups of study participants) with self-reported physical activity (1987-2004). They analyzed associations of physical activity with the incidence of 26 kinds of cancer.The study included 1.4 million participants and 186,932 cancers were identified during a median of 11 years of follow-up.

The authors report that higher levels of physical activity compared to lower levels were associated with lower risks of 13 of 26 cancers: esophageal adenocarcinoma (42 percent lower risk); liver (27 percent lower risk); lung (26 percent lower risk); kidney (23 percent lower risk); gastric cardia (22 percent lower risk); endometrial (21 percent lower risk); myeloid leukemia (20 percent lower risk); myeloma (17 percent lower risk); colon (16 percent lower risk); head and neck (15 percent lower risk), rectal (13 percent lower risk); bladder (13 percent lower risk); and breast (10 percent lower risk). Most of the associations remained regardless of body size or smoking history, according to the article. Overall, a higher level of physical activity was associated with a 7 percent lower risk of total cancer.

Physical activity was associated with a 5 percent higher risk of prostate cancer and a 27 percent higher risk of malignant melanoma, an association that was significant in regions of the U.S. with higher levels of solar UV radiation but not in regions with lower levels, the results showed.

The authors note the main limitation of their study is that they cannot fully exclude the possibility that diet, smoking and other factors may affect the results. Also, the study used self-reported physical activity, which can mean errors in recall."These findings support promoting physical activity as a key component of population-wide cancer prevention and control efforts," the authors conclude.

Published on Leave a comment on Father Passes Down More Than DNA to Baby

That a male's preconception behaviors and exposure to all sorts of environmental contaminants (alcohol, drugs, medicines, chemicals at work, pesticides, etc) has effects on sperm and is linked to birth defects has been known for decades. What is new is the focus on epigenetics, or as some researchers call it: inherited paternal epigenetics. Three different paternal influences that affect the fetus and child (thus paternal experiences influence what the child inherits) are discussed in a review article: paternal age, environmental factors, and alcohol consumption.The researchers also found that environmental effects during the lifetime of a father can affect not only his immediate offspring, but also future generations.

What is epigenetics? Researchers in the study summarized it as: "Epigenetics are heritable alterations in gene expression that do not involve changes in the germline DNA sequence. It works primarily through three mechanisms: DNA methylation, histone modification, and microRNA (miRNA) expression."

Huh? This means that in epigenetics, the DNA doesn't change, but external or environmental factors switch genes on and off and affect how cells read genes. In other words, it's how the environment can alter gene expression without changing the genetic code. Epigenetic change is a regular and natural occurrence, but can also be influenced by several factors: age, the environment/lifestyle (such as diet, alcohol consumption, and chemical exposure), and disease state.  For example, what you eat and how much you drink (alcohol), where you live, what chemicals you're exposed to, how you exercise, even aging – all of these can eventually cause chemical modifications around the genes that will turn those genes on or off over time. Additionally, in certain diseases such as cancer or Alzheimer’s, various genes will be switched into the opposite state, away from the normal/healthy state. From Science Daily:

Fathers' age, lifestyle associated with birth defects

A growing body of research is revealing associations between birth defects and a father's age, alcohol use and environmental factors, say researchers at Georgetown University Medical Center. They say these defects result from epigenetic alterations that can potentially affect multiple generations. The study, published in the American Journal of Stem Cells, suggest both parents contribute to the health status of their offspring -- a common sense conclusion which science is only now beginning to demonstrate, says the study's senior investigator, Joanna Kitlinska, PhD, an associate professor in biochemistry, and molecular and cellular biology.

"We know the nutritional, hormonal and psychological environment provided by the mother permanently alters organ structure, cellular response and gene expression in her offspring," she says. "But our study shows the same thing to be true with fathers -- his lifestyle, and how old he is, can be reflected in molecules that control gene function," she says. "In this way, a father can affect not only his immediate offspring, but future generations as well."

For example, a newborn can be diagnosed with fetal alcohol spectrum disorder (FASD), even though the mother has never consumed alcohol, Kitlinska says. "Up to 75 percent of children with FASD have biological fathers who are alcoholics, suggesting that preconceptual paternal alcohol consumption negatively impacts their offspring."

The report is a review of evidence, human and animal, published to date on the link between fathers and heritable epigenetic programming. Among the studies reviewed are ones that find: - Advanced age of a father is correlated with elevated rates of schizophrenia, autism, and birth defects in his children; - A limited diet during a father's pre-adolescence has been linked to reduced risk of cardiovascular death in his children and grandchildren; - Paternal obesity is linked to enlarged fat cells, changes in metabolic regulation, diabetes, obesity and development of brain cancer; - Psychosocial stress on the father is linked to defective behavioral traits in his offspring; and - Paternal alcohol use leads to decreased newborn birth weight, marked reduction in overall brain size and impaired cognitive function.

Published on Leave a comment on Reduce Chronic Inflammation With Food

As we know, chronic inflammation is linked to cancer and other diseases. It is long-term persistent low-grade inflammation, and it has a "wear and tear" effect on the body. What causes chronic inflammation? Being overweight or obese, sedentary lifestyle, Western (low fiber, high processed foods and meat) diet, chronic illnesses, viruses or bacteria (e.g., gum disease), smoking, air pollution, stress, excessive alcohol intake. It often does not have symptoms, but doctors can test for C-reactive protein levels (CRP), which increase when the body is inflamed. So you absolutely want to lower chronic inflammation if you can.

High dietary intake of fruits and vegetables, which are rich in polyphenols, has been linked through many studies with reduced risk for diseases that are associated with chronic inflammation, such as cardiovascular disease, type II diabetes, cancers, Alzheimer’s disease, and Parkinson’s disease. Polyphenols are a class of chemicals or micronutrients found in many foods, especially fruits and vegetables.

New research looked at 31 polyphenols (alone and in some mixtures) to see which lowered inflammation the most. They found that some mixtures of polyphenols actually had more than an additive effect - that it's more than a sum of the individual polyphenols. They found that the polyphenols resveratrol, isorhamnetin, and curcumin were the most anti-inflammatory. Isorhamnetin is a flavonol that occurs in apples, onions and green tea; curcumin is from the Indian spice turmeric; and resveratrol is present in the skin of red, purple and black grapes, and in especially high concentrations in Itadori tea (from Japanese knotweed). Another important anti-inflammatory polyphenol is vanillic acid, which is found in vanilla, wine, whole wheat, and berries.

Just remember that it is better to eat a variety of fruits and vegetables rather than taking supplements. Foods are more than just one or 2 isolated ingredients, but consist of many micronutrients, microbes, etc , and when eating a varied diet, a person typically has mixtures of many polyphenols in their system at once. The research finds that these polyphenol mixtures interact with one another. Studies  typically find real foods to be superior to supplements in beneficial health effects. From Science Daily:

What foods can help fight the risk of chronic inflammation?

A new study by the University of Liverpool's Institute of Ageing and Chronic Disease has identified food stuffs that can help prevent chronic inflammation that contributes to many leading causes of death. Inflammation occurs naturally in the body but when it goes wrong or goes on too long, it can trigger disease processes. Uncontrolled inflammation plays a role in many major diseases, including cancer, heart disease, diabetes and Alzheimer's disease.

Diets rich in fruits and vegetables, which contain polyphenols, protect against age-related inflammation and chronic diseases. Polyphenols are abundant micronutrients in our diet, and evidence for their role in the prevention of degenerative diseases such as cancer and cardiovascular diseases is already emerging. The health effects of polyphenols depend on the amount consumed and on their bioavailability.

T-cells, or T-lymphocytes, are a type of white blood cell that circulate around our bodies, scanning for cellular abnormalities and infections. They contribute to cell signalling molecules (cytokines) that aid cell-to-cell communication in immune responses and stimulate the movement of cells towards sites of inflammation, infection and trauma. Cytokines are modulated by fruit and vegetable intake.

The study, conducted by Sian Richardson and Dr Chris Ford from the University's Institute of Ageing and Chronic Disease, examined the different potencies of the polyphenols. Sian Richardson, said: "The results of our study suggest that (poly)phenols derived from onions, turmeric, red grapes, green tea and açai berries may help reduce the release of pro-inflammatory mediators in people at risk of chronic inflammation. "Older people are more susceptible to chronic inflammation and as such they may benefit from supplementing their diets with isorhamnetin, resveratrol, curcumin and vanillic acid or with food sources that yield these bioactive molecules."

Published on Leave a comment on Sugar and Cancer

Great article about cancer and sugar. Yes, there is more and more research recently finding a connection with sugar, raised insulin levels, and cancer (as in sugar feeds cancer). Do go read it. Some excerpts from the May 15 Sunday magazine of the NY Times:

AN OLD IDEA, REVIVED: STARVE CANCER TO DEATH

Today Boveri is celebrated for discovering the origins of cancer, but another German scientist, Otto Warburg, was studying sea-urchin eggs around the same time as Boveri. His research, too, was hailed as a major breakthrough in our understanding of cancer. But in the following decades, Warburg’s discovery would largely disappear from the cancer narrative, his contributions considered so negligible that they were left out of textbooks altogether.

By the time Warburg turned his attention from sea-urchin cells to the cells of a rat tumor, in 1923, he knew that sea-urchin eggs increased their oxygen consumption significantly as they grew, so he expected to see a similar need for extra oxygen in the rat tumor. Instead, the cancer cells fueled their growth by swallowing up enormous amounts of glucose (blood sugar) and breaking it down without oxygen. The result made no sense. Oxygen-fueled reactions are a much more efficient way of turning food into energy, and there was plenty of oxygen available for the cancer cells to use. But when Warburg tested additional tumors, including ones from humans, he saw the same effect every time. The cancer cells were ravenous for glucose.

Warburg’s discovery, later named the Warburg effect, is estimated to occur in up to 80 percent of cancers. It is so fundamental to most cancers that a positron emission tomography (PET) scan, which has emerged as an important tool in the staging and diagnosis of cancer, works simply by revealing the places in the body where cells are consuming extra glucose. In many cases, the more glucose a tumor consumes, the worse a patient’s prognosis.  ...continue reading "Sugar and Cancer"

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Published on 4 Comments on Treat Dandruff With a Scalp Probiotic?

Dandruff is a very common scalp disorder that has occurred for centuries. A new study found that the most abundant bacteria on the scalp are Propionibacterium and Staphylococcus, and that they have a reciprocal relationship with each other - when one is high, the other is low. When compared with a normal scalp, dandruff regions had decreased Propionibacterium and increased Staphylococcus. The researchers suggested that these findings suggest a new way to treat dandruff - to increase the Propionibacterium and decrease the Staphylococcus on the scalp. Stay tuned for possible future treatments using these findings. From Science Daily:

Bacteria the yin and yang of dandruff, says study

Dandruff is not caused by a fungus, as many believe, but by an imbalance between two competing bacteria that naturally colonise the human scalp, according to a study released Thursday. Think of Propionibacterium and Staphylococcus as the yin and yang of healthy hair: when they hold each other in check, so too is dandruff held at bay. But when one dominates the other, the tell-tale white flecks that settle on shoulders like snowdust begin to proliferate, a team of Chinese and Japanese researchers reported.

Dandruff is the most common scalp disorder on the planet, a tonsorial bane for about half the world's population. But experts have differed sharply over the years on its causes and possible cures....A team anchored by Zhang Menghui of Shanghai Jiao Tong University isolated a large number of variables in the ecosystem of the human scalp to see how they interact. In 59 Chinese volunteers aged from 18 to 60 years old, they measured levels of water, several dozen bacteria, sebum—an oily secretion that proliferates in adolescence and early adulthood....Participants washed their hair 48 hours in advance of the tests, and dandruff samples were taken from eight different sections of the scalp.

"Overall, fungi did not exhibit an important role in the severity of dandruff," they concluded.
"The relationship between the bacteria and the dandruff was significantly stronger."
But the scientists also noticed that prevalence of the pesky white particles was higher when the ratio of two dominant bacteria—which normally cancel each other out—was altered. "This study suggests that adjusting the balance of the bacteria on the scalp... might be a potential solution to lessen dandruff," they concluded.