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Published on 1 Comment on Obesity Markers Found In Urine

You can deceive yourself by calling yourself "big-boned" or "hefty", but your urine doesn't lie! Researchers found 29 biological markers in urine that are associated with body mass. These biological markers in urine are a "metabolic signature" of obesity. Note: Body mass index (BMI) is a measure of body fat based on height and weight that applies to adult men and women. From Medical Xpress:

Urine profiles provide clues to how obesity causes disease

Scientists have identified chemical markers in urine associated with body mass, providing insights into how obesity causes disease. Being overweight or obese is associated with higher risk of heart disease, stroke, diabetes and cancer, but the mechanisms connecting body fat and disease are not well understood.

The new study, led by Imperial College London, shows that obesity has a 'metabolic signature' detectable in urine samples, pointing to processes that could be targeted to mitigate its effects on health. 

Urine contains a variety of chemicals known as metabolites, from a vast range of biochemical processes in the body. Technologies that analyse the metabolic makeup of a sample can therefore offer huge amounts of information that reflects both a person's genetic makeup and lifestyle factors.

The Imperial researchers analysed urine samples from over 2,000 volunteers in the US and the UK. They found 29 different metabolic products whose levels correlated with the person's body mass index, and how they fit together in a complex network that links many different parts of the body.

Some of these metabolites are produced by bacteria that live in the gut, highlighting the potentially important role these organisms play in obesity. Altered patterns of energy-related metabolites produced in the muscles were also identified as being linked to obesity.

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Since so many people are taking Vitamin D supplements because of its supposed health benefits, the question becomes - how much is too much? For those desiring to take vitamin D supplements, what is a good maintenance dosage to take daily? That question has not been answered from the studies I've seen other than 1000 units per day is safe. However, sunlight is the best and safest source of vitamin D (even though that makes dermatologists nuts because of their concern with sunlight leading to skin cancer).From Science Daily:

Vitamin D toxicity rare in people who take supplements, researchers report

Over the last decade, numerous studies have shown that many Americans have low vitamin D levels and as a result, vitamin D supplement use has climbed in recent years. Vitamin D has been shown to boost bone health and it may play a role in preventing diabetes, cancer, cardiovascular disease and other illnesses. In light of the increased use of vitamin D supplements, Mayo Clinic researchers set out to learn more about the health of those with high vitamin D levels. They found that toxic levels are actually rare.

A vitamin D level greater than 50 nanograms per milliliter is considered high. Vitamin D levels are determined by a blood test called a serum 25-hydroxyvitamin D blood test. A normal level is 20-50 ng/mL, and deficiency is considered anything less than 20 ng/mL, according the Institute of Medicine (IOM).

The researchers analyzed data collected between 2002 and 2011 from patients in the Rochester Epidemiology Project...Of 20,308 measurements, 8 percent of the people who had their vitamin D measured had levels greater than 50 ng/mL, and less than 1 percent had levels over 100 ng/mL.

"We found that even in those with high levels of vitamin D over 50 ng/mL, there was not an increased risk of hypercalcemia, or elevated serum calcium, with increasing levels of vitamin D," says study co-author Thomas D. Thacher, M.D., a family medicine expert at Mayo Clinic. Hypercalcemia, or high blood calcium, can occur when there are very high levels of vitamin D in the blood. Too much calcium in the blood can cause weakness, lead to kidney stones, and interfere with the heart and brain, and even be life threatening.

The Mayo researchers also found that women over age 65 were at the highest risk of having vitamin D levels above 50 ng/mL. The result was not surprising because that's a group that often takes vitamin D supplements, Dr. Thacher says. Another notable outcome: The occurrence of high vitamin D levels over 50 ng/mL increased during the 10-year period of the study, from nine per 100,000 people at the start of the study up to 233 per 100,000 by the end.

Only one case over the 10-year study period was identified as true acute vitamin D toxicity; the person's vitamin D level was 364 ng/mL. The individual had been taking 50,000 international units (IU) of vitamin D supplements every day for more than three months, as well as calcium supplements. The IOM-recommended upper limit of vitamin D supplementation for people with low or deficient levels is 4,000 IU a day. 

Some natural sources of vitamin D include oily fish such as mackerel and salmon, fortified milk, and sunlight.

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This nice general summary of what scientists know about the microbial community within us was just published by a division of the NIH (National Institutes of Health). Very simple and basic. From the National Institute of General Medical Sciences (NIGMS):

Facts about our microbial menagerie

Trillions of microorganisms inhabit us -- inside and out. Scientists are surveying these microbial metropolises to learn more about their role in health. Microbiologists Darren Sledjeski of the National Institutes of Health (NIH) and Andrew Goodman of Yale University share a few details of what researchers have learned so far.

1. The majority of the microbes that inhabit us are bacteria. The rest of the microbial menagerie is fungi and viruses, including ones that infect the bacteria! Collectively, our resident microorganisms are referred to as the human microbiota, and their genomes are called the human microbiome.

2. Our bodies harbor more bacterial cells than human ones. Even so, the microbiota accounts for less than 3 percent of a person's body mass. That's because our cells are up to 10,000 times bigger in volume than bacterial cells.

3. Your collection of bacteria has more genes than you do. Scientists estimate that the genomes of gut bacteria contain 100-fold or more genes than our own genomes. For this reason, the human microbiome is sometimes called our second genome.

4. Most of our microbes are harmless, and some are helpful. For example, harmless microbes on the skin keep infectious microbes from occupying that space. Microbes in the colon break down lactose and other complex carbohydrates that our bodies can't naturally digest.

5. Different microbes occupy different parts of the body. Some skin bacteria prefer the oily nooks near the nose, while others like the dry terrain of the forearm. Bacteria don't all fare well in the same environment and have adapted to live in certain niches.

6. Each person's microbiota is unique. The demographics of microbiota differ among individuals. Diet is one reason. Also, while a type of microbe might be part of one person's normal microbial flora, it might not be part of another's, and could potentially make that person sick.

7. Host-microbial interactions are universal. Microbial communities may vary from person to person, but everyone's got them, including other creatures. For this reason, researchers can use model organisms to tease apart the complexities of host-microbial interactions and develop broad principles for understanding them. The mouse is the most widely used animal model for microbiome studies.

8. The role of microbiota in our health isn't entirely clear. While it's now well accepted that the microbial communities that inhabit us are actively involved in a range of conditions -- from asthma to obesity -- research studies have not yet pinpointed why or how. In other words, the results may suggest that the presence of a bacterial community is associated with a disease, but they don't show cause and effect.

9. Most of our microbes have not been grown in the lab. Microbes require a certain mix of nutrients and other microbes to survive, making it challenging to replicate their natural environments in a petri dish. New culturing techniques are enabling scientists to study previously uncultivated microbes.

10. The impact of probiotic and prebiotic products isn't clear. Fundamental knowledge gaps remain regarding how these products may work and what effects they might have on host-microbial interactions. A new NIH effort to stimulate research in this area is under way.

11. There's even more we don't know! Additional areas of research include studying the functions of microbial genes and the effects of gut microbes on medicines. The more we learn from these and other studies, the more we'll understand how our normal microbiota interacts with us and how to apply that knowledge to promote our health.

Lactobacilli. Credit: Wikipedia.

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Another study finding negative effects of air pollution - this time high levels of traffic-related air pollution is linked to slower cognitive development among 7 to 10 year old children in Barcelona, Spain. From Science Daily:

Air pollution linked to slower cognitive development in children

Attendance at schools exposed to high levels of traffic-related air pollution is linked to slower cognitive development among 7- to 10-year-old children in Barcelona, according to a new study.

The researchers measured three cognitive outcomes (working memory, superior working memory, and attentiveness) every 3 months over a 12-month period in 2715 primary school children attending 39 schools. By comparing the development of these cognitive outcomes in the children attending schools where exposure to air pollution was high to those children attending a school with a similar socio-economic index where exposure to pollution was low, they found that the increase in cognitive development over time among children attending highly polluted schools was less than among children attending paired lowly polluted schools, even after adjusting for additional factors that affect cognitive development.

Thus, for example, there was an 11.5% 12-month increase in working memory at the lowly polluted schools but only a 7.4% 12-month increase in working memory at the highly polluted schools. These results were confirmed using direct measurements of traffic related pollutants at schools.

The findings suggest that the developing brain may be vulnerable to traffic-related air pollution well into middle childhood, a conclusion that has implications for the design of air pollution regulations and for the location of new schools. While the authors controlled for socioeconomic factors, the accuracy of these findings may be limited by residual confounding, that is, the children attending schools where traffic-related pollution is high might have shared other unknown characteristics that affected their cognitive development.

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Long-term air pollution can cause damage to the brain: covert brain infarcts ("silent strokes") and smaller brain volume (equal to one year of brain aging).

The authors of a study looking at 900 men in the Boston area concluded that, on average, participants who lived in more polluted areas had the brain volume of someone 1 year older vs participants who lived in less polluted areas, and they also had a 46% higher risk for silent strokes. While the mechanisms of how air pollution may affect brain aging is unclear, the researchers think that inflammation resulting from the deposit of fine particles in the lungs is important. From Science Daily:

Long-term exposure to air pollution may pose risk to brain structure, cognitive functions

Air pollution, even at moderate levels, has long been recognized as a factor in raising the risk of stroke. A new study led by scientists from Beth Israel Deaconess Medical Center and Boston University School of Medicine suggests that long-term exposure can cause damage to brain structures and impair cognitive function in middle-aged and older adults. 

Writing in the May 2015 issue of Stroke, researchers who studied more than 900 participants of the Framingham Heart Study found evidence of smaller brain structure and of covert brain infarcts, a type of "silent" ischemic stroke resulting from a blockage in the blood vessels supplying the brain.

The study evaluated how far participants lived from major roadways and used satellite imagery to assess prolonged exposure to ambient fine particulate matter, particles with a diameter of 2.5 millionth of a meter, referred to as PM2.5. These particles come from a variety of sources, including power plants, factories, trucks and automobiles and the burning of wood. They can travel deeply into the lungs and have been associated in other studies with increased numbers of hospital admissions for cardiovascular events such as heart attacks and strokes.

Study participants were at least 60 years old and were free of dementia and stroke. The evaluation included total cerebral brain volume, a marker of age-associated brain atrophy; hippocampal volume, which reflect changes in the area of the brain that controls memory; white matter hyperintensity volume, which can be used as a measure of pathology and aging; and covert brain infarcts.

The study found that an increase of only 2µg per cubic meter in PM2.5, a range commonly observed across metropolitan regions in New England and New York, was associated with being more likely to have covert brain infarcts and smaller cerebral brain volume, equivalent to approximately one year of brain aging...."This is concerning since we know that silent strokes increase the risk of overt strokes and of developing dementia, walking problems and depression."

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For years doctors said babies "didn't feel pain like adults" (they said it was just a "reflex") and so all sorts of procedures and operations were done on infants without pain relief medication. This research shows those doctors were wrong and not giving infants pain relief medications is just cruel. From Medical Xpress:

Babies feel pain 'like adults'

The brains of babies 'light up' in a very similar way to adults when exposed to the same painful stimulus, a pioneering Oxford University brain scanning study has discovered. It suggests that babies experience pain much like adults.

The study looked at 10 healthy infants aged between one and six days old and 10 healthy adults aged 23-36 years....During the research babies, accompanied by parents and clinical staff, were placed in a Magnetic Resonance Imaging (MRI) scanner where they usually fell asleep. MRI scans were then taken of the babies' brains as they were 'poked' on the bottom of their feet with a special retracting rod creating a sensation 'like being poked with a pencil' - mild enough that it did not wake them up. These scans were then compared with brain scans of adults exposed to the same pain stimulus.

The researchers found that 18 of the 20 brain regions active in adults experiencing pain were active in babies. Scans also showed that babies' brains had the same response to a weak 'poke' (of force 128mN) as adults did to a stimulus four times as strong (512mN). The findings suggest that not only do babies experience pain much like adults but that they also have a much lower pain threshold.

'This is particularly important when it comes to pain: obviously babies can't tell us about their experience of pain and it is difficult to infer pain from visual observations. In fact some people have argued that babies' brains are not developed enough for them to really 'feel' pain, any reaction being just a reflex - our study provides the first really strong evidence that this is not the case.' The researchers say that it is now possible to see pain 'happening' inside the infant brain and it looks a lot like pain in adults.

As recently as the 1980s it was common practice for babies to be given neuromuscular blocks but no pain relief medication during surgery [1]. In 2014 a review of neonatal pain management practice in intensive care highlighted that although such infants experience an average of 11 painful procedures per day 60% of babies do not receive any kind of pain medication [2].

Our study suggests that not only do babies experience pain but they may be more sensitive to it than adults,' said Dr Slater. 'We have to think that if we would provide pain relief for an older child undergoing a procedure then we should look at giving pain relief to an infant undergoing a similar procedure.'

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The Center for Public Integrity, a nonpartisan, nonprofit investigative news organization has just published a number of articles about how companies have added thousands of ingredients to foods with little or no government oversight. This loophole is a decades old law that allows an additive to be "generally recognized as safe" or GRAS without the FDA getting involved. This is why there are some additives in American foods that are NOT allowed in Europe or other countries. And that is why I always read the ingredient lists of foods. I even hate to buy foods that have the nice sounding "natural ingredients" in the ingredient list. What are these so-called natural ingredients that have been concocted in some lab and added to our foods? Does anyone know?  Some earlier posts on this issue: August 19, 2014 and June 16, 2014 . The following are excerpts from the April 14, 2015 story from NPR:

Why The FDA Has Never Looked At Some Of The Additives In Our Food

Companies have added thousands of ingredients to foods with little to no government oversight. That's thanks to a loophole in a decades-old law that allows them to deem an additive to be "generally recognized as safe" — or GRAS — without the U.S. Food and Drug Administration's blessing, or even its knowledge.

The loophole was originally intended to allow manufacturers of common ingredients like vinegar and table salt — when added to processed foods — to bypass the FDA's lengthy safety-review process. But over time, companies have found that it's far more efficient to take advantage of the exemption to get their products on shelves quickly. Some of these products contain additives that the FDA has found to pose dangers. And even ingredients the agency has agreed are GRAS are now drawing scrutiny from scientists and consumer groups that dispute their safety.

Critics of the system say the biggest concern, however, is that companies regularly introduce new additives without ever informing the FDA. That means people are consuming foods with added flavors, preservatives and other ingredients that are not reviewed at all by regulators for immediate dangers or long-term health effects. The vast majority of food additives are safe. Some, however, have proved to cause severe allergic reactions or other long-term health effects. Scientists and advocates worry about the growing number of ingredients that the FDA doesn't know about and is not tracking.

Rather than going through the painstaking FDA-led review process to ensure that their new ingredients are safe, food companies can determine on their own that substances are "generally recognized as safe." They can then ask the FDA to review their evaluation — if they wish. Or they can take their ingredients straight to market, without ever informing the agency."FDA doesn't know what it doesn't know," said Steve Morris of the Government Accountability Office, which published a report in 2010 that found that "FDA's oversight process does not help ensure the safety of all new GRAS determinations."

For a company to determine that an ingredient is "generally recognized as safe," it must establish that the additive's safety is commonly understood by qualified scientific experts. But some ingredients defy consensus, as consumers, scientific groups and sometimes even the FDA have pointed out. Even GRAS additives that have been used in food for decades are now coming under fire as their uses expand and scientific research emerges that casts doubt on their safety. This is true of one of the most known — and vilified — GRAS additives: partially hydrogenated oil, a form of trans fat. Widely used in food products including fried foods and cake mixes, trans fats have been named by public health experts as a contributor to heart disease, stroke and Type 2 diabetes. Despite strong pushback from industry, the FDA in November 2013 made a tentative determination that artificial trans fats should not have GRAS status, and the agency is likely to make that determination final this summer.

But it's the ingredients the public doesn't know about that have critics of the GRAS system most worried. Researchers for the Pew Charitable Trusts and the Natural Resources Defense Council say that allowing companies to make safety determinations without telling the FDA makes it nearly impossible to identify whether there are health effects caused by long-term exposure to certain ingredients.

Their concerns are heightened because safety decisions often rest in the hands of a small group of scientific experts selected by companies or consulting firms with a financial incentive to get new ingredients on the market. Several of these scientists, a Center for Public Integrity investigation found, previously served as scientific consultants for tobacco companies during the 1980s and 1990s, when the tobacco industry fought vigorously to defend its products.

The GRAS loophole was born in 1958. Americans were growing concerned about the increased use of preservatives and other additives in food, so Congress passed — and President Dwight Eisenhower signed — the first law regulating ingredients added to food.

To restore confidence, the law set up a system requiring companies to submit new ingredients to an extensive FDA safety review before going to market..."There are plenty of ingredients that are receiving GRAS status the safety of which are in dispute." In the past five decades, the number of food additives has skyrocketed — from about 800 to more than 10,000. They are added to everything from baked goods and breakfast cereals to energy bars and carbonated drinks.

For the full investigation, head to the Center for Public Integrity's site. 

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Interesting findings - that squirming and fidgeting in ADHD children may be how they learn best and actually aids them in learning. So don't try to stop or suppress the fidgeting and squirming, but instead embrace it. I know of an excellent science teacher who would hand out small chunks of beeswax modeling clay to children who couldn't stop squirming and fidgeting in class - and this helped them focus and learn. From Science Daily:

Kids with ADHD must squirm to learn, study says

For decades, frustrated parents and teachers have barked at fidgety children with ADHD to "Sit still and concentrate!" But new research conducted at UCF shows that if you want ADHD kids to learn, you have to let them squirm. The foot-tapping, leg-swinging and chair-scooting movements of children with attention-deficit/hyperactivity disorder are actually vital to how they remember information and work out complex cognitive tasks, according to a study published in an early online release of the Journal of Abnormal Child Psychology.

The findings show the longtime prevailing methods for helping children with ADHD may be misguided. "The typical interventions target reducing hyperactivity. It's exactly the opposite of what we should be doing for a majority of children with ADHD," said one of the study's authors, Mark Rapport, head of the Children's Learning Clinic at the University of Central Florida. "The message isn't 'Let them run around the room,' but you need to be able to facilitate their movement so they can maintain the level of alertness necessary for cognitive activities."

The study at the UCF clinic included 52 boys ages 8 to 12. Twenty-nine of the children had been diagnosed with ADHD and the other 23 had no clinical disorders and showed normal development. Each child was asked to perform a series of standardized tasks designed to gauge "working memory," the system for temporarily storing and managing information required to carry out complex cognitive tasks such as learning, reasoning and comprehension... A high-speed camera recorded the kids, and observers recorded their every movement and gauged their attention to the task.

Rapport's previous research had already shown that the excessive movement that's a trademark of hyperactive children -- previously thought to be ever-present -- is actually apparent only when they need to use the brain's executive brain functions, especially their working memory.The new study goes an important step further, proving the movement serves a purpose. "What we've found is that when they're moving the most, the majority of them perform better," Rapport said. "They have to move to maintain alertness." By contrast, the children in the study without ADHD also moved more during the cognitive tests, but it had the opposite effect: They performed worse.

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Well worth reading in its entirety. In summary: Anyone who is physically capable of activity should try to reach at least 150 minutes of physical activity per week (walking is good) and have around 20 to 30 minutes of that be vigorous activity. This significantly lowers the risk of dying prematurely. (NOTE: the second study mentioned was in the April 8, 2015 post: Physical Activity That Makes You Sweat Is Good ) From the New York Times:

The Right Dose of Exercise for a Longer Life

Exercise has had a Goldilocks problem, with experts debating just how much exercise is too little, too much or just the right amount to improve health and longevity. Two new, impressively large-scale studies provide some clarity, suggesting that the ideal dose of exercise for a long life is a bit more than many of us currently believe we should get, but less than many of us might expect. The studies also found that prolonged or intense exercise is unlikely to be harmful and could add years to people’s lives.

The current broad guidelines from governmental and health organizations call for 150 minutes of moderate exercise per week to build and maintain health and fitness. But whether that amount of exercise represents the least amount that someone should do — the minimum recommended dose — or the ideal amount has not been certain.

In the broader of the two studies, researchers with the National Cancer Institute, Harvard University and other institutions gathered and pooled data about people’s exercise habits from six large, ongoing health surveys, winding up with information about more than 661,000 adults, most of them middle-aged. Using this data, the researchers stratified the adults by their weekly exercise time, from those who did not exercise at all to those who worked out for 10 times the current recommendations or more (meaning that the exercised moderately for 25 hours per week or more). Then they compared 14 years’ worth of death records for the group.

They found that, unsurprisingly, the people who did not exercise at all were at the highest risk of early death. But those who exercised a little, not meeting the recommendations but doing something, lowered their risk of premature death by 20 percent. Those who met the guidelines precisely, completing 150 minutes per week of moderate exercise, enjoyed greater longevity benefits and 31 percent less risk of dying during the 14-year period compared with those who never exercised.

The sweet spot for exercise benefits, however, came among those who tripled the recommended level of exercise, working out moderately, mostly by walking, for 450 minutes per week, or a little more than an hour per day. Those people were 39 percent less likely to die prematurely than people who never exercised. At that point, the benefits plateaued, the researchers found, but they never significantly declined. Those few individuals engaging in 10 times or more the recommended exercise dose gained about the same reduction in mortality risk as people who simply met the guidelines. They did not gain significantly more health bang for all of those additional hours spent sweating. But they also did not increase their risk of dying young.

The other new study of exercise and mortality reached a somewhat similar conclusion about intensity.  {NOTE: SEE APRIL 8, 2015 POST FOR DETAILS}

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The following is a list of nutrients that some researchers (from the Institute of Food Technology) think of as especially beneficial to the brain. Other researchers may (or probably will) focus on other nutrients. I am posting it even though I generally dislike articles that talk about "superfoods" or an itemized list of foods that one should eat to the exclusion of others. Because, of course, focusing on some nutrients may leave out many just as important nutrients.

Also, medical thinking changes over time and what was once considered "unhealthy" may later be considered a wonderful food (remember when eggs, nuts, and coconuts were almost considered evil?). And vice versa (remember when margarine with partially hydrogeneated oils and trans-fats was considered healthier than butter?) And study after study says it is better to eat the foods, rather than take supplements. So keep in mind that the following nutrients are found in whole foods and in a varied diet. And when they mention a specific food such as blueberries, remember that ALL berries have benefits (though they vary), so eat a variety of berries. Same with nuts - eat a variety and not just walnuts. From Science Daily:

Eight nutrients to protect the aging brain

Brain health is the second most important component in maintaining a healthy lifestyle according to a 2014 AARP study. As people age they can experience a range of cognitive issues from decreased critical thinking to dementia and Alzheimer's disease. In the March issue of Food Technology published by the Institute of Food Technologists (IFT), contributing editor Linda Milo Ohr writes about eight nutrients that may help keep your brain in good shape.

1. Cocoa Flavanols: Cocoa flavanols have been linked to improved circulation and heart health, and preliminary research shows a possible connection to memory improvement as well. A study showed cocoa flavanols may improve the function of a specific part of the brain called the dentate gyrus, which is associated with age-related memory (Brickman, 2014). {NOTE: good sources are cocoa and dark chocolate}

2. Omega-3 Fatty Acids: Omega-3 fatty acids have long been shown to contribute to good heart health are now playing a role in cognitive health as well....Foods rich in omega-3s include salmon, flaxseed oil, and chia seeds.

3. Phosphatidylserine and Phosphatidic Acid: Two pilot studies showed that a combination of phosphatidylserine and phosphatidic acid can help benefit memory, mood, and cognitive function in the elderly (Lonza, 2014). {NOTE: good sources are fish and meat}

4. Walnuts: A diet supplemented with walnuts may have a beneficial effect in reducing the risk, delaying the onset, or slowing the progression of Alzheimer's disease in mice (Muthaiyah, 2014).

5. Citicoline: Citicoline is a natural substance found in the body's cells and helps in the development of brain tissue, which helps regulate memory and cognitive function, enhances communication between neurons, and protects neural structures from free radical damage.... {NOTE: Citocoline is synthesized in the body from choline, so see foods high in choline}

6. Choline: Choline, which is associated with liver health and women's health, also helps with the communication systems for cells within the brain and the rest of the body. Choline may also support the brain during aging and help prevent changes in brain chemistry that result in cognitive decline and failure. A major source of choline in the diet are eggs. { NOTE: Good sources of choline are eggs, meat, fish, beans, and cruciferous vegetables.}

7. Magnesium: Magnesium supplements are often recommended for those who experienced serious concussions. Magnesium-rich foods include avocado, soy beans, bananas and dark chocolate.

8. Blueberries: Blueberries are known to have antioxidant and anti-inflammatory activity because they boast a high concentration of anthocyanins, a flavonoid that enhances the health-promoting quality of foods. Moderate blueberry consumption could offer neurocognitive benefits such as increased neural signaling in the brain centers.