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Author: Sima

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Interesting, but does it really mean anything? Just change to a new toothbrush monthly.From Science Daily:

Up to 3,000 times the bacterial growth on hollow-head toothbrushes

Solid-head power toothbrushes retain less bacteria compared to hollow-head toothbrushes, according to new research.

Lead author and professor at the UTHealth School of Dentistry, Donna Warren Morris, R.D.H., M.Ed., notes that microbial counts were lower in the solid-head toothbrush group than in the two hollow-head toothbrush groups in 9 out of 10 comparisons. "Toothbrushes can transmit microorganisms that cause disease and infections. A solid-head design allows for less growth of bacteria and bristles should be soft and made of nylon," Morris said. 

The study was conducted over a three-week period where participants brushed twice daily with one out of three randomly assigned power toothbrushes. Participants used non-antimicrobial toothpaste and continued their flossing routine throughout the study, but refrained from using other dental products like mouthwash.

During the study the brush heads were exposed to five categories of oral microorganisms: anaerobes and facultative microorganisms, yeast and mold, oral streptococci and oral enterococci anaerobes, Porphyromonas gingivalis andFusobacterium species.

The article also states that there is no present or published study that has demonstrated that bacterial growth on toothbrushes can lead to systematic health effects, but as Morris stated, several microorganisms have been associated with systemic diseases.

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Published on 1 Comment on Stick With a Weight Loss Diet for Best Results

Two write-ups about the same large study.The good news is that there is no one diet that works - the key is to stick with the diet. From Science Daily:

Comparison of named diet programs finds little difference in weight loss outcomes

In an analysis of data from nearly 50 trials including about 7,300 individuals, significant weight loss was observed with any low-carbohydrate or low-fat diet, with weight loss differences between diet programs small, findings that support the practice of recommending any diet that a patient will adhere to in order to lose weight.

Bradley C. Johnston, Ph.D., of the Hospital for Sick Children Research Institute, Toronto, and McMaster University, Hamilton, Ontario, and colleagues conducted a meta-analysis to assess the relative effectiveness of different popular diets in improving weight loss. 

The meta-analysis included 59 articles that reported 48 randomized clinical trials (7,286 individuals; median age, 46 years; median weight, 207.5 lbs.). In the diet-class analysis adjusted for exercise and behavioral support, all treatments were superior to no diet at 6-month follow-up. Compared with no diet, low-carbohydrate diets had a median difference in weight loss of 19.2 lbs. and low-fat diets had similar estimated effects (17.6 lbs.).

At 12-month follow-up, the estimated average weight losses of all diet classes compared with no diet were approximately 2.2 to 4.4 lbs. less than after 6-month follow-up. The diet classes of low fat (16 lbs.) and low carbohydrate (16 lbs.) continued to have the largest estimated treatment effects.

Weight loss differences between individual diets were minimal. "Our findings should be reassuring to clinicians and the public that there is no need for a one-size-fits­ all approach to dieting because many different diets appear to offer considerable weight loss benefits. 

From Medical Xpress:

Any diet works, if you stick to it, study finds

At six month follow-up, people on low-carbohydrate diets lost 19 more pounds than those who were not on a diet, while those on low-fat diets lost 17 more pounds than those on no diet. After 12 months about two to three pounds of that difference was gone, and there was no difference between low-carbohydrate and low-fat diets.

Behavioural support in a diet made a difference at six months, enhancing weight loss by about seven pounds, while exercise was significant at 12 months, improving weight loss by about four and half pounds.

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Same research study is discussed as in the last post (Your Bacteria All Over Your Home), but different write-up with more and different details. From Washington Post:

Hotel rooms aren’t yucky – you colonize them with your own personal bacteria within hours

When you move from one house to another, you take all your bacteria with you. In fact, your family's microbiome (or your eco-system of inner and outer bacteria) lays claim to hotel rooms with hours. Our bacterial signatures are so persistent and so unique, a new study published Thursday in Science reports, that they could even be used in forensic investigations — and eventually become more useful to police than an old-fashioned fingerprint. And the same research that could track down a serial killer could also help you raise healthier kids.

In studying seven families as they moved from one house to another, the microbiologists had one major takeaway: Bacteria move from your body to your living space at incredible speed.

"Everyone thinks hotels are icky," said Jack Gilbert,, corresponding author of the study and environmental microbiologist at Argonne National Laboratory, "but when one young couple we studied moved into a hotel, it was microbiologically identical to their home within 24 hours." And unpublished further research reveals that the time frame is even swifter than that. "No matter what you do to clean a hotel room," Gilbert said, "your microbial signal has wiped out basically every trace of the previous resident within hours."

What's more, the researchers were able to determine how much individuals in a family interacted, what rooms they used, and even when they'd last been to one part of the house or another. This has obvious applications in forensic science. "We could go all J. Edgar Hoover on this and make a database of microbial fingerprints of people all over the world," Gilbert said, "and it's far more sophisticated than a standard fingerprint, which is just a presence or absence indication. We can see who they are, where they're from, the diet they're eating, when they left, who they may have been interacting with. It gets pretty crazy."

Gilbert and his colleagues are already working with police in Hawaii, hoping to look at the microbiome left on dead bodies. "If someone is, shall we say, recently and inappropriately deceased," Gilbert said, "we can look at their bacterial colonies and try to identify who the last person to come into contact with them was, and when." Based on some promising animal studies, he said, it could be possible. "An actual fingerprint is rarely left on a body," Gilbert said, "but a microbial fingerprint certainly is."

The Home Microbiome Study has more immediate applications, too. Gilbert, a father of two, hopes that fellow parents will use these and future findings to raise their offspring in healthier microbiomes. Before the age of two, the human microbiome remains in flux. Different species of bacteria compete to gain permanent spots — and once the race is run, you're basically stuck with the winners. Research in animals has shown that bacterial exposure in youth can impact physical and mental development and health for the rest of an organism's life.

"Let's say a kid grows up in an apartment block, without going outside much," Gilbert said. "They're just getting this same human bacteria fed back to them, day after day." More exposure is most certainly the better route.

For starters, get a dog. Partway through the study, Gilbert did just that. "We saw dogs acting as a super-charged conduit," he said, "transferring bacteria between one human and another, and bringing in outdoor bacteria. They just run around distributing microbes all willy-nilly." Sure enough, his family saw their home's microbiome benefit from the new addition.

We now know that most bacteria are beneficial to us — and that some can even prevent allergies."Imagine if we could engineer our home environments, optimize our carpeting and air conditioning systems, to bring in the really good bacteria," he said. 

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Exciting research! From Science Daily:

Home is where the microbes are

A person's home is their castle, and they populate it with their own subjects: millions and millions of bacteria. Scientists have detailed the microbes that live in houses and apartments. The study was conducted by researchers from the U.S. Department of Energy's Argonne National Laboratory and the University of Chicago. 

The results shed light on the complicated interaction between humans and the microbes that live on and around us. Mounting evidence suggests that these microscopic, teeming communities play a role in human health and disease treatment and transmission.

"We know that certain bacteria can make it easier for mice to put on weight, for example, and that others influence brain development in young mice," said Argonne microbiologist Jack Gilbert, who led the study. "We want to know where these bacteria come from, and as people spend more and more time indoors, we wanted to map out the microbes that live in our homes and the likelihood that they will settle on us.

The Home Microbiome Project followed seven families, which included eighteen people, three dogs and one cat, over the course of six weeks. The participants in the study swabbed their hands, feet and noses daily to collect a sample of the microbial populations living in and on them. They also sampled surfaces in the house, including doorknobs, light switches, floors and countertops. Then the samples came to Argonne, where researchers performed DNA analysis to characterize the different species of microbes in each sample.

They found that people substantially affected the microbial communities in a house -- when three of the families moved, it took less than a day for the new house to look just like the old one, microbially speaking.

Regular physical contact between individuals also mattered -- in one home where two of the three occupants were in a relationship with one another, the couple shared many more microbes. Married couples and their young children also shared most of their microbial community.

Within a household, hands were the most likely to have similar microbes, while noses showed more individual variation. Adding pets changed the makeup as well, Gilbert said -- they found more plant and soil bacteria in houses with indoor-outdoor dogs or cats.

In at least one case, the researchers tracked a potentially pathogenic strain of bacteria called Enterobacter, which first appeared on one person's hands, then the kitchen counter, and then another person's hands. "It's also quite possible that we are routinely exposed to harmful bacteria -- living on us and in our environment -- but it only causes disease when our immune systems are otherwise disrupted."

Home microbiome studies also could potentially serve as a forensic tool, Gilbert said. Given an unidentified sample from a floor in this study, he said, "we could easily predict which family it came from."

The research also suggests that when a person (and their microbes) leaves a house, the microbial community shifts noticeably in a matter of days."You could theoretically predict whether a person has lived in this location, and how recently, with very good accuracy," he said.

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An interesting article that discusses research that finds advantages to being dyslexic. Perhaps think in terms of cognitive diversity. From Scientific American:

The Advantages of Dyslexia

With reading difficulties can come other cognitive strengths.

In our laboratory at the Harvard-Smithsonian Center for Astrophysics we have carried out studies funded by the National Science Foundation to investigate talents for science among those with dyslexia. The dyslexic scientist Christopher Tonkin described to me his sense of this as a sensitivity to “things out of place.”  He’s easily bothered by the weeds among the flowers in his garden, and he felt that this sensitivity for visual anomalies was something he built on in his career as a professional scientist.  Such differences in sensitivity for causal perception may explain why people like Carole Greider and Baruj Benacerraf have been able to perform Nobel prize-winning science despite lifelong challenges with dyslexia.

Why are there advantages in dyslexia?  Is it something about the brains of people with dyslexia that predisposes them to causal thinking? Or, is it a form of compensation, differences in the brain that occur because people with dyslexia read less? Unfortunately, the answer to these questions is unknown.

One thing we do know for sure is that reading changes the structure of the brain. An avid reader might read for an hour or more a day, day in and day out for years on end. This highly specialized repetitive training, requiring an unnaturally precise, split-second control over eye movements, can quickly restructure the visual system so as to make some pathways more efficient than the others.

My colleagues and I suggested that one reason people with dyslexia may exhibit visual talents is that they have difficulty managing visual attention⁠. It may at first seem ironic that a difficulty can lead to an advantage, but it makes sense when you realize that what we call “advantages” and “disadvantages” have meaning only in the context of the task that needs to be performed.

For example, imagine you’re looking to hire a talented security guard. This person’s job will be to spot things that look odd and out of place, and call the police when something suspicious —say, an unexpected footprint in a flowerbed— is spotted. If this is the person’s task, would you rather hire a person who is an excellent reader, who has the ability to focus deeply and get lost in the text, or would you rather hire a person who is sensitive to changes in their visual environment, who is less apt to focus and block out the world?

Tasks such as reading require an ability to focus your attention on the words as your eyes scan a sentence, to quickly and accurately shift your attention in sequence from one word to the next.  But, to be a good security guard you need an opposite skill; you need to be able to be alert to everything all at once, and though this isn’t helpful for reading, this can lead to talents in other areas.

A series of studies by an Italian team led by Andrea Facoetti have shown that children with dyslexia often exhibit impairments in visual attention. In one study,Facoetti’s team measured visual attention in 82 preschool children who had not yet been taught to read. The researchers then waited a few years until these children finished second grade, and then examined how well each child had learned reading. They found that those who had difficulty focusing their visual attention in preschool had more difficulty learning to read.

These studies raise the possibility that visual attention deficits, present from a very early age, are responsible for the reading challenges that are characteristic of dyslexia. If this theory is upheld, it would also suggest that the observed advantages are not an incidental byproduct of experience with reading, but are instead the result of differences in the brain that were likely present from birth.

If this is indeed the case, given that attention affects perception in very general ways, any number of advantages should emerge.  While people with dyslexia may tend to miss details in their environment that require an attentional focus, they would be expected to be better at noticing things that are distributed more broadly.  To put this another way, while typical readers may tend to miss the forest because its view is blocked by all the trees, people with dyslexia may see things more holistically, and miss the trees, but see the forest.

Among other advantages observed, Gadi Geiger and his colleagues at MIT found that people with dyslexia can distribute their attention far more broadly than do typical readers, successfully identifying letters flashed simultaneously in the center and the periphery for spacings that were much further apart. They also showed that such advantages are not just for things that are visual, but that they apply to sounds as well. In one study, simulating the sounds of a cocktail party, they found that people with dyslexia were able to pick out more words spoken by voices widely-distributed in the room, compared with people who were proficient readers.

Whether or not observations of such advantages —measured in the laboratory— have applications to talents in real life remains an open question. But, whatever the reason, a clear trend is beginning to emerge: People with dyslexia may exhibit strengths for seeing the big picture (both literally and figuratively) others tend to miss.  Thomas G. West has long-argued that out-of-the-box thinking is historically part and parcel of dyslexia, and more recently physicians Brock and Fernette Eide have advanced similar arguments. Sociologists, such as Julie Logan of the Cass Business School in London agree.  Logan found that dyslexia is relatively common among business entrepreneurs; people who tend to think differently and see the big picture in thinking creatively about a business.

Whatever the mechanism, one thing is clear: dyslexia is associated with differences in visual abilities, and these differences can be an advantage in many circumstances, such as those that occur in science, technology, engineering and mathematics. It’s only when everything is all the same that nothing productive can get done. Neurological differences similarly drive the engine of society, to create the contrasts between hot and cold that lead to productive work. Impairments in one area can lead to advantages in others, and it is these differences that drive progress in many fields, including science and math.

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Eating more tomatoes is doable, tastes delicious, and reduces prostate cancer risk! From Science Daily:

Fighting prostate cancer with tomato-rich diet

Men who eat over 10 portions a week of tomatoes have an 18 percent lower risk of developing prostate cancer, new research suggests. With 35,000 new cases every year in the UK, and around 10,000 deaths, prostate cancer is the second most common cancer in men worldwide. Rates are higher in developed countries, which some experts believe is linked to a Westernised diet and lifestyle.

To assess if following dietary and lifestyle recommendations reduces risk of prostate cancer, researchers at the Universities of Bristol, Cambridge and Oxford looked at the diets and lifestyle of 1,806 men aged between 50 and 69 with prostate cancer and compared with 12,005 cancer-free men.

The NIHR-funded study, published in the medical journal Cancer Epidemiology, Biomarkers and Prevention, is the first study of its kind to develop a prostate cancer 'dietary index' which consists of dietary components -- selenium, calcium and foods rich in lycopene -- that have been linked to prostate cancer. Men who had optimal intake of these three dietary components had a lower risk of prostate cancer.

Tomatoes and its products -- such as tomato juice and baked beans -- were shown to be most beneficial, with an 18 per cent reduction in risk found in men eating over 10 portions a week. This is thought to be due to lycopene, an antioxidant which fights off toxins that can cause DNA and cell damage. 

The researchers also looked at the recommendations on physical activity, diet and body weight for cancer prevention published by the World Cancer Research Fund (WCRF) and the American Institute for Cancer Research (AICR). Only the recommendation on plant foods -- high intake of fruits, vegetables and dietary fibre -- was found to be associated with a reduced risk of prostate cancer. 

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If taking Clostridia as a probiotic for food allergies works, it would be amazing for food allergy sufferers. Very exciting research. From Time:

The Bacteria That May One Day Cure Food Allergies

Every round of antibiotics a person takes will wipe out strains of bacteria inside the body, some of which are eliminated forever. Considering how early and how often antibiotics are administered to kids—coupled with our increasingly antimicrobial lifestyles—we’ve become more prone to allergies and other ailments, the hygiene hypothesis goes. There’s no cure for food allergies, just lifestyle adjustments and abstention. But Nagler and her team may have the germ of an idea for treatment using gut bacteria, according to a new mice study published in the Proceedings of the National Academy of Sciences.

The team dosed two groups of mice with peanut allergens. One group of mice had been bred to be entirely without gut germs; the other group had sparsely populated gut bacteria due to treatment with antibiotics. Both groups of mice had higher levels of the allergen in their bloodstream compared to mice with healthy gut-bacteria populations.

After giving those same mice a mix that contained the bacteria strain Clostridia, their allergen levels plummeted. Infusing the mice with another group of intestinal bacteria, Bacteroides, didn’t help—so the researchers think the effect is special to Clostridia. “These bacteria are very abundant and they reside very close to the epithelial lining, so they’re in intimate contact with the immune system,” Nagler says.

Next, they’ll transfer gut bacteria from food-allergic infants and healthy infants into germ-free mice, Nagler says. “If we give back Clostridia to a mouse that has the bacteria of an allergic child, can we now reverse susceptibility in that mouse?”

This is a more in-depth article of the research. From Science Daily:

Gut bacteria that protect against food allergies identified

The presence of Clostridia, a common class of gut bacteria, protects against food allergies, a new study in mice finds. The discovery points toward probiotic therapies for this so-far untreatable condition. Food allergies affect 15 million Americans, including one in 13 children, who live with this potentially life-threatening disease that currently has no cure, researchers note.

Although the causes of food allergy -- a sometimes deadly immune response to certain foods -- are unknown, studies have hinted that modern hygienic or dietary practices may play a role by disturbing the body's natural bacterial composition. In recent years, food allergy rates among children have risen sharply -- increasing approximately 50 percent between 1997 and 2011 -- and studies have shown a correlation to antibiotic and antimicrobial use.

"Environmental stimuli such as antibiotic overuse, high fat diets, caesarean birth, removal of common pathogens and even formula feeding have affected the microbiota with which we've co-evolved," said study senior author Cathryn Nagler, PhD, Bunning Food Allergy Professor at the University of Chicago. "Our results suggest this could contribute to the increasing susceptibility to food allergies."

To test how gut bacteria affect food allergies, Nagler and her team investigated the response to food allergens in mice. ...This sensitization to food allergens could be reversed, however, by reintroducing a mix of Clostridia bacteria back into the mice. Reintroduction of another major group of intestinal bacteria, Bacteroides, failed to alleviate sensitization, indicating that Clostridia have a unique, protective role against food allergens.

To identify this protective mechanism, Nagler and her team studied cellular and molecular immune responses to bacteria in the gut. Genetic analysis revealed that Clostridia caused innate immune cells to produce high levels of interleukin-22 (IL-22), a signaling molecule known to decrease the permeability of the intestinal lining.

While complex and largely undetermined factors such as genetics greatly affect whether individuals develop food allergies and how they manifest, the identification of a bacteria-induced barrier-protective response represents a new paradigm for preventing sensitization to food. Clostridia bacteria are common in humans and represent a clear target for potential therapeutics that prevent or treat food allergies. 

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Interesting study that definitely needs follow-up to see if it also applies to women. Nice news for coffee drinkers - that coffee consumption may have protective effects against gum disease. From Medical Xpress:

Coffee drinkers—your gums may thank you

Coffee contains antioxidants. Antioxidants fight gum disease. Does coffee, then, help fight gum disease?  Lead author and 2014 DMD graduate Nathan Ng said, "We found that coffee consumption did not have an adverse effect on periodontal health, and, instead, may have protective effects against periodontal disease."

Coffee consumption was associated with a small but statistically significant reduction in number of teeth with periodontal bone loss. Researchers concluded that coffee consumption may be protective against periodontal bone loss in adult males—the group examined in the study.

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Several more articles on the benefits of exercise. From Science Daily:

Train your heart to protect your mind

Exercising to improve our cardiovascular strength may protect us from cognitive impairment as we age, according to a new study. "Our body's arteries stiffen with age, and the vessel hardening is believed to begin in the aorta, the main vessel coming out of the heart, before reaching the brain. Indeed, the hardening may contribute to cognitive changes that occur during a similar time frame," explained the first author of the study. "We found that older adults whose aortas were in a better condition and who had greater aerobic fitness performed better on a cognitive test. We therefore think that the preservation of vessel elasticity may be one of the mechanisms that enables exercise to slow cognitive aging."

The researchers worked with 31 young people between the ages of 18 and 30 and 54 older participants aged between 55 and 75. This enabled the team to compare the older participants within their peer group and against the younger group who obviously have not begun the aging processes in question. None of the participants had physical or mental health issues that might influence the study outcome.

The results demonstrated age-related declines in executive function, aortic elasticity and cardiorespiratory fitness, a link between vascular health and brain function, and a positive association between aerobic fitness and brain function. "Although the impact of fitness on cerebral vasculature may however involve other, more complex mechanisms, overall these results support the hypothesis that lifestyle helps maintain the elasticity of arteries, thereby preventing downstream cerebrovascular damage and resulting in preserved cognitive abilities in later life."

From Science Daily:

Physically fit kids have beefier brain white matter than their less-fit peers

A new study of 9- and 10-year-olds finds that those who are more aerobically fit have more fibrous and compact white-matter tracts in the brain than their peers who are less fit. 'White matter' describes the bundles of axons that carry nerve signals from one brain region to another. More compact white matter is associated with faster and more efficient nerve activity.

The analysis revealed significant fitness-related differences in the integrity of several white-matter tracts in the brain: the corpus callosum, which connects the brain's left and right hemispheres; the superior longitudinal fasciculus, a pair of structures that connect the frontal and parietal lobes; and the superior corona radiata, which connect the cerebral cortex to the brain stem."All of these tracts have been found to play a role in attention and memory," Chaddock-Heyman said. 

From Science Daily:

Exercise may protect older women from irregular heartbeat

Increasing the amount or intensity of physical activity can cut the chances of older women developing a life-threatening irregular heartbeat, according to new research. Researchers found that post-menopausal women who were the most physically active had a 10 percent lower risk of developing atrial fibrillation (AF), compared to women with low levels of physical activity, even if they were obese. Obesity is an important risk factor for atrial fibrillation.

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Reading this article, I kept thinking of vampires and Transylvania. But the million dollar question is - will it work? From New Scientist:

Young blood to be used in ultimate rejuvenation trial

 In October, people with Alzheimer's disease will be injected with the blood of young people in the hope that it will reverse some of the damage caused by the condition.

The scientists behind the experiment have evidence on their side. Work in animals has shown that a transfusion of young mouse blood can improve cognition and the health of several organs in older mice. It could even make those animals look younger. The ramifications for the cosmetics and pharmaceutical industries could be huge if the same thing happens in people.

Disregarding vampire legends, the idea of refreshing old blood with new harks back to the 1950s, when Clive McCay of Cornell University in Ithaca, New York, stitched together the circulatory systems of an old and young mouse – a technique called heterochronic parabiosis. He found that the cartilage of the old mice soon appeared younger than would be expected.

It wasn't until recently, however, that the mechanisms behind this experiment were more clearly understood. In 2005, Thomas Rando at Stanford University in California and his team found that young blood returned the liver and skeletal stem cells of old mice to a more youthful state during heterochronic parabiosis. The old mice were also able to repair injured muscles as well as young mice (Nature, doi.org/d4fkt5). Spooky things seemed to happen in the opposite direction, too: young mice that received old blood appeared to age prematurely. In some cases, injured muscles did not heal as fast as would be expected.

Several other experiments have shown similar effects. In 2012, Amy Wagers at Harvard University showed that young blood can reverse heart decline in old mice.

Once the researchers had ruled out the effect of reduced blood pressure on the older mice, they identified a protein in the blood plasma called growth differentiation factor 11 (GDF11) that appeared to fall with age. To see if it was linked to the rejuvenating effects, the team gave old mice with enlarged hearts daily injections of GDF11 for 30 days. Their hearts decreased in size almost as much as they had in the parabiosis experiments (Cell, doi.org/q2f).

In both mice and humans, GDF11 falls with age. We don't know why it declines, but we know it is involved in several mechanisms that control growth. It is also thought to mediate some age-related effects on the brain, in part by activation of another protein that is involved in neuronal growth and long-term memory.

So the billion-dollar question is: would a GDF11 boost have the same effect in humans? Wyss-Coray thinks it will, having taken the next step of injecting young human blood plasma into old mice. His preliminary results suggest that human blood has similar rejuvenating benefits for old mice as young mouse blood does.

"We saw these astounding effects," he says. "The human blood had beneficial effects on every organ we've studied so far."

Now, the final step – giving young human blood plasma to older people with a medical condition – is about to begin. Getting approval to perform the experiment in humans has been relatively simple, says Wyss-Coray, thanks to the long safety record of blood transfusions. So in early October, a team at Stanford School of Medicine will give a transfusion of blood plasma donated by people under 30 to older volunteers with mild to moderate Alzheimer's.

Following the impressive results in animal experiments, the team hopes to see immediate improvements in cognition, but Wyss-Coray cautions that it is still very experimental. All researchers involved in the work agree that GDF11 is unlikely to be the only factor that keeps organs youthful. "It's too optimistic to think there would be just one factor," says Francesco Loffredo, who studies the effects of young blood in old animals at Harvard University. "It's much more likely to be several factors that exert these effects in combination."

Alessandro Laviano at the Sapienza University of Rome in Italy says that the research on diseases of ageing certainly holds promise, but he is more interested in the potential use of young blood in chronic disease. ...Before moving to clinical trials in people with cancer we need to learn more about the dynamics of the beneficial factors in blood, says Laviano, such as when they are at their peak. Do we reach a peak at 5 or 35 years? "We just don't know," he says.

An earlier related exciting study (from May 2014) in which it was found that "the blood of young mice has the ability to restore mental capabilities in old mice". From Science Daily:

Infusion of young blood recharges brains of old mice