Release Date 15 MAY 2015
Draft Report Compiled by
In this issue:
1. Oil or fat?
2. Potassium improved blood pressure in teen girls, salt had no adverse effect
3. Diet swap has dramatic effects on colon cancer risk for Americans and Africans
4. Prevent type 2 diabetes blood-sugar spikes by eating more protein for breakfast
5. Vitamin D toxicity rare in people who take supplements, Mayo Clinic researchers report
6. Viruses: You’ve heard the bad — here’s the good
7. Green tea extract and exercise hinder progress of Alzheimer’s disease in mice
8. Strong statin-diabetes link seen in large study of Tricare patients
9. Naturally occurring amino acid could improve oral health
10. Antioxidant effects of coffee by-products 500 times greater than vitamin C
11. Prenatal exercise lowers risks of C-sections, higher birth weights
12. Campaign to reduce the harms of too much medicine comes to the UK
13. Infant antibiotic use linked to adult diseases
14. Anemia distorts regular method of diabetes diagnosis and questions its reliability
15. Link between vitamin E and exposure to air pollution
16. 30 minutes of physical activity 6 days a week linked to 40 percent lower risk of death in elderly men
Public Release: 27-Apr-2015
Oil or fat?
Saturated fatty acids might directly damage heart
Olive oil is universally considered a much healthier alternative to meat fat. Plant-derived oils (such as olive oil, canola oil, and vegetable oil) largely consist of unsaturated fatty acids, whereas animal fat is richer in the saturated ones. After a typical meal, carbohydrates are the primary source of energy production by the heart. Under fasting conditions, however, free fatty acids become the major energy producer. Saturated fat in a diet is known to be detrimental to heart health, but its impact on the cardiac muscle has been studied only recently.
Interestingly, while saturated fatty acids are toxic to cells, unsaturated fatty acids are not only harmless but also provide protection against the damage done by saturated fatty acids. Studies conducted on many cell lines have indicated that saturated fatty acids can cause cell death involving the “endoplasmic reticulum stress (ER stress)”, a cellular process known to be involved in the development of many diseases. A new paper, “Saturated fatty acids induce endoplasmic reticulum stress in primary cardiomyocytes“, just published in open access in “Endoplasmic Reticulum Stress in Diseases” by De Gruyter Open shows that there are striking differences in the accumulation of saturated and unsaturated fatty acids in cardiac muscle cells, and that saturated fatty acids induce the death of these cells through the ER stress. In stalking contrast, unsaturated fatty acids protect the same cells from such damage.
A research group from the Montreal Heart Institute in Canada, led by Dr. Nicolas Bousette, evaluated the impact of palmitate and oleate on cellular fatty acid absorption, triglyceride synthesis, intracellular lipid distribution, ER stress, and cell death in primary cardiomyocytes. This is the first time that such phenomena were observed in cells directly derived from the heart, validating a critical role for saturated fatty acids in the development of heart diseases. Given a primary role for lipid metabolism in the development of type II diabetes, the current finding might suggest a probable role for saturated fatty acids in the development of heart conditions among diabetic patients. The current results and future research in this direction might improve our understanding on the possible connection between intracardiomyocyte lipid accumulation and the development of diabetic cardiomyopathy.
The article is available fully in open access to read, download and share on De Gruyter Online
Public Release: 27-Apr-2015
Potassium improved blood pressure in teen girls, salt had no adverse effect
Eating 3,000 mg per day of salt or more appears to have no adverse effect on blood pressure in adolescent girls, while those girls who consumed 2,400 mg per day or more of potassium had lower blood pressure at the end of adolescence, according to an article published online by JAMA Pediatrics.
The scientific community has historically believed most people in the United States consume too much salt in their diets. The current Dietary Guidelines for Americans recommends limiting sodium intake to less than 2,300 mg per day for healthy individuals between the ages of 2 and 50. The relationship between dietary sodium and blood pressure in children and adolescents is largely unexamined in prospective studies, according to the study background.
Lynn L. Moore, D.Sc., M.P.H., of the Boston University School of Medicine, and coauthors examined the long-term effects of dietary sodium and potassium on blood pressure at the end of adolescence. The authors used data from the National Heart, Lung and Blood Institute’s Growth and Health Study and participants included 2,185 black and white girls (ages 9 to 10) who were followed up for 10 years.
The authors found no evidence that higher sodium intakes (3,000 to <4,000 mg per day and ?4,000 mg per day vs. < 2,500 mg per day) had an adverse effect on adolescent blood pressure. Some analysis showed that those girls consuming 3,500 mg per day or more of salt had generally lower diastolic blood pressures than girls who consumed less than 2,500 mg per day. Food consumption was based on self reports and blood pressure was measured annually.
Overall, girls in the highest category of potassium intake (2,400 mg per day or more) had lower late-adolescent systolic and diastolic blood pressure than those girls who consumed less potassium, the results show.
Girls who consumed the most sodium and potassium consumed the most calories too, along with the most dairy, fruits, vegetables and fiber, according to the results.
“This prospective study showed that black and white adolescent girls who consumed more dietary potassium had lower BPs [blood pressures] in later adolescence. In contrast, the data indicated no overall effect of sodium intake alone on BP, and, thus do not support the call for a global reduction in sodium intake among children and adolescents. This study emphasizes the need to develop methods for estimating salt sensitivity to be used in future studies of high-risk populations and points to the potential health risks associated with the existing low dietary potassium intakes among U.S. children and adolescents,” the study concludes.
Diet swap has dramatic effects on colon cancer risk for Americans and Africans
Scientists have found dramatic effects on risk factors for colon cancer when American and African volunteers swapped diets for just two weeks.
Western diets, high in protein and fat but low in fibre, are thought to raise colon cancer risk compared with African diets high in fibre and low in fat and protein.
The new study, published in Nature Communications today, confirms that a high fibre diet can substantially reduce risk, and shows that bacteria living in the gut play an important role in this effect.
Colon cancer is the fourth commonest cause of death from cancer worldwide, accounting for over 600,000 deaths per year. Colon cancer rates are much higher in the western world than in Africa or the Far East, yet in the United States, African Americans shoulder the greatest burden of the disease.
To investigate the possible roles of diet and gut bacteria, an international team including scientists from the University of Pittsburgh and Imperial College London carried out a study with a group of 20 African American volunteers and another group of 20 participants from rural South Africa. The two groups swapped diets under tightly controlled conditions for two weeks.
The volunteers had colonoscopy examinations before and after the diet swap. The researchers also measured biological markers that indicate colon cancer risk and studied samples of bacteria taken from the colon.
At the start, when the groups had been eating their normal diets, almost half of the American subjects had polyps — abnormal growths in the bowel lining that may be harmless but can progress to cancer. None of the Africans had these abnormalities.
After two weeks on the African diet, the American group had significantly less inflammation in the colon and reduced biomarkers of cancer risk. In the African group, measurements indicating cancer risk dramatically increased after two weeks on the western diet.
Professor Jeremy Nicholson, the team leader from the Department of Surgery and Cancer at Imperial College London, said: “We can’t definitively tell from these measurements that the change in their diet would have led to more cancer in the African group or less in the American group, but there is good evidence from other studies that the changes we observed are signs of cancer risk.
“The findings suggest that people can substantially lower their risk of colon cancer by eating more fibre. This is not new in itself but what is really surprising is how quickly and dramatically the risk markers can switch in both groups following diet change. These findings also raise serious concerns that the progressive westernization of African communities may lead to the emergence of colon cancer as a major health issue.”
Professor Stephen O’Keefe at the University of Pittsburgh, who directed the study, said: “Studies on Japanese migrants to Hawaii have shown that it takes one generation of westernization to change their low incidence of colon cancer to the high rates observed in native Hawaiians. Our study suggests that westernization of the diet induces changes in biomarkers of colon cancer risk in the colonic mucosa within two weeks. Perhaps even more importantly, a change in diet from a westernized composition to a ‘traditional African’ high fiber low fat diet reduced these biomarkers of cancer risk within two weeks, indicating that it is likely never too late to change your diet to change your risk of colon cancer.”
The study found that a major reason for the changes in cancer risk was the way in which the bacteria in the gut — known as the microbiome — altered their metabolism to adapt to the new diet. In the American group, the researchers found that the African diet led to an increase in the production of butyrate, a byproduct of fibre metabolism that has important anti-cancer effects.
Dr James Kinross, a colorectal surgeon and a member of the research group at Imperial, said: “The gut microbiome is being increasingly recognized as an important contributor to human health. This research shows that gut bacteria are critically important for mediating the link between diet and colon cancer risk. This means we can look to develop therapies targeting gut bacteria as a way to prevent and treat cancer.”
The study was funded by the National Institutes of Health in the US and the National Institute for Health Research Imperial Biomedical Research Centre in the UK.
Public Release: 29-Apr-2015
Prevent type 2 diabetes blood-sugar spikes by eating more protein for breakfast
COLUMBIA, Mo. — Individuals with Type 2 Diabetes have difficulty regulating their glucose — or blood sugar — levels, particularly after meals. Now, University of Missouri researchers have found that Type 2 diabetics can eat more protein at breakfast to help reduce glucose spikes at both breakfast and lunch.
“People often assume that their glucose response at one meal will be identical to their responses at other meals, but that really isn’t the case,” said Jill Kanaley, professor and associate chair in the MU Department of Nutrition and Exercise Physiology. “For instance, we know that what you eat and when you eat make a difference, and that if people skip breakfast, their glucose response at lunch will be huge. In our study, we found those who ate breakfast experienced appropriate glucose responses after lunch.”
Kanaley and her colleagues monitored Type 2 diabetics’ levels of glucose, insulin and several gut hormones — which help regulate the insulin response — after breakfast and lunch. The participants ate either high-protein or high-carbohydrate breakfasts, and the lunch included a standard amount of protein and carbohydrates.
The researchers found eating more protein at breakfast lowered individuals’ post-meal glucose levels. Insulin levels were slightly elevated after the lunch meal, which demonstrated that individuals’ bodies were working appropriately to regulate blood-sugar levels, Kanaley said.
“The first meal of the day is critical in maintaining glycemic control at later meals, so it really primes people for the rest of the day,” Kanaley said. “Eating breakfast prompts cells to increase concentrations of insulin at the second meal, which is good because it shows that the body is acting appropriately by trying to regulate glucose levels. However, it is important for Type 2 diabetics to understand that different foods will affect them differently, and to really understand how they respond to meals, they need to consistently track their glucose. Trigger foods may change depending on how much physical activity people have gotten that day or how long they have waited between meals.”
Kanaley said that although it would be helpful for individuals with high blood sugar to eat more protein, they do not need to consume extreme amounts of protein to reap the benefits.
“We suggest consuming 25 to 30 grams of protein at breakfast, which is within the range of the FDA recommendations,” Kanaley said.
Public Release: 30-Apr-2015
Vitamin D toxicity rare in people who take supplements, Mayo Clinic researchers report
Rochester, Minn. — 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.
Their study appears in the May issue of Mayo Clinic Proceedings.
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, a National Institutes of Health-funded medical records pool that makes Olmsted County, Minn., the home of Mayo Clinic, one of the few places worldwide where scientists can study virtually an entire geographic population to identify health trends.
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.
“We were surprised by that degree of dramatic increase in vitamin D levels,” Dr. Thacher says.
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.
It’s important for doctors to ask their patients about the doses of vitamin D supplements that they are using, Dr. Thacher says, because even capsules containing as much as 50,000 IU of vitamin D are available without prescription. If taken on a daily basis, that amount could lead to toxicity.
Some natural sources of vitamin D include oily fish such as mackerel and salmon, fortified milk, and sunlight.
“Our bodies will naturally produce vitamin D when our skin is exposed to sunlight, however, we don’t recommend excessive exposure to sun due to the risk of skin cancer,” Dr. Thacher added.
In an accompanying editorial in Mayo Clinic Proceedings, Dr. Michael F. Hollick, Ph.D., M.D., describes vitamin D’s dramatic medical history, the need for judicious dosing, but the importance of vitamin D supplementation in those with low or deficient levels.
“The evidence is clear that vitamin D toxicity is one of the rarest medical conditions and is typically due to intentional or inadvertent intake of extremely high doses,” writes Hollick, a professor of medicine, physiology and biophysics at Boston University School of Medicine.
Public Release: 30-Apr-2015
Viruses: You’ve heard the bad — here’s the good
American Society for Microbiology
“The word, virus, connotes morbidity and mortality, but that bad reputation is not universally deserved,” said Marilyn Roossinck, PhD, Professor of Plant Pathology and Environmental Microbiology and Biology at the Pennsylvania State University, University Park. “Viruses, like bacteria, can be important beneficial microbes in human health and in agriculture,” she said. Her review of the current literature on beneficial viruses appeared ahead of print April 24 in the Journal of Virology, which is published by the American Society for Microbiology.
In sharp contrast to the gastrointestinal distress it causes in humans, the murine (mouse infecting) norovirus plays a role in development of the mouse intestine and its immune system, and can actually replace the beneficial effects of certain gut bacteria when these have been decimated by antibiotics. Normal, healthy gut bacteria help prevent infection by bacteria that cause gastrointestinal illness, but excessive antibiotic intake can kill the normal gut flora, and make one vulnerable to gastrointestinal disease. However, norovirus infection of mice actually restored the normal function of the immune system’s lymphocytes and the normal morphology of the intestine, said Roossinck.
Mammalian viruses can also provide immunity against bacterial pathogens. Gamma-herpesviruses boost mice resistance to Listeria monocytogenes, an important human gastrointestinal pathogen, and to Yersinia pestis, otherwise known as plague. “Humans are often infected with their own gamma-herpes viruses, and it is conceivable that these could provide similar benefits,” said Roossinck.
Latent herpesviruses also arm natural killer cells, an important component of the immune system, which kill both mammalian tumor cells, and cells that are infected with pathogenic viruses.
The gastrointestinal tracts of mammals are plush with viruses. So far, little is known about how these viruses affect their hosts, but their sheer number and diversity suggest that they have important functions, said Roossinck. For example, GI viruses that infect bacteria–known as phage–may modulate expression of bacterial genes involved in host digestion.
Recent research shows that bacteriophage stick to the mucus membranes of many metazoans (the class “Animalia,” which includes everything from worms to wombats). And mucus membranes, Roossinck points out, are the points of entry for many bacterial pathogens, suggesting that they provide the first line of defense against invading bacteria.
Viruses also provide a variety of services for plants. A few plants grow in the hot soils surrounding the geysers and the “Artists’ Paintpots” of Yellowstone National Park. One such plant, which is a type of tropical panic grass, is a symbiosis that includes a fungus that colonizes the plant, and a virus that infects that fungus. All three members of this symbiosis are necessary for survival in soils simmering at more than 122 degrees Fahrenheit.
In the laboratory, Roossinck has created symbioses between the same virus-infected fungus and other plants. This has enabled every plant her group has tested to survive at these elevated soil temperatures, including tomato, she says, noting that she has pushed the soil temperature to 140 degrees without killing the plant.
Investigators have also found that certain viruses can render some plants drought tolerant, and at least one example of virally-conferred cold tolerance has been discovered– discoveries that could become useful for expanding the ranges of crops.
Plants are often infected with “persistent viruses” that are passed down from generation to generation, perhaps over thousands of years, with viruses that are transmitted to nearly 100 percent of their plant progeny, but that have never been shown to be transmitted from one plant to another. “One such virus, white clover crytpic virus, suppresses formation of nitrogen-fixing nodules when adequate nitrogen is present in the soil, saving the plant from producing a costly organ when it is not needed” said Roossinck.
Other beneficial viruses are the ancient retroviruses that long ago made a permanent home in the genome, or that left genes therein, said Roossinck. “The mammalian genes for syncitin, essential in the establishment of the placenta, are retroviral env genes that were incorporated on several different occasions,” Roossinck writes. “They even function differently in ruminants compared to other mammals… these elements are considered viral fossils that can help us understand the deep evolution of viruses.”
“Viruses are beyond a doubt the coolest things I have ever encountered,” said Roossinck. “They do truly amazing things with very little genetic information. I was always a little disturbed at the bad rap they get, so it was very exciting for me to find good ones.”
Public Release: 4-May-2015
Green tea extract and exercise hinder progress of Alzheimer’s disease in mice
Comprehensive study of EGCG, a compound found in green tea, could lead to treatments of Alzheimer’s in humans
University of Missouri-Columbia
COLUMBIA, Mo. — According to the National Institutes of Health (NIH), Alzheimer’s disease (AD) may affect as many as 5.5 million Americans. Scientists currently are seeking treatments and therapies found in common foods that will help stave off the disease or prevent it completely. Now, University of Missouri researchers have determined that a compound found in green tea, and voluntary exercise, slows the progression of the disease in mice and may reverse its effects. Further study of the commonly found extract could lead to advancements in the treatment and prevention of Alzheimer’s disease in humans.
“In Alzheimer’s patients, amyloid-beta peptide (A-beta) can accumulate and clump together causing amyloid plaques in the brain,” said Todd Schachtman, professor of psychological sciences in the College of Arts and Science at MU. “Symptoms can include increased memory loss and confusion, agitation and a lack of concern for your environment and surroundings. We looked at ways of preventing or postponing the onset of the disease which we hope can eventually lead to an improvement of health status and quality of life for the elderly.”
Increases in inflammation have been linked to Alzheimer’s disease patients and recent studies have suggested the benefits of dietary antioxidants in reducing the risk of AD. Based on previous research conducted at Mizzou, researchers decided to investigate the effects of voluntary exercise and epigallocatechin-3-gallate (EGCG), a green tea extract, on memory function and A-beta levels in mice known to show plaque deposits and behavior deficits.
First, mice were placed in the center of a specialized maze and allowed to move around with the aim of finding the right hole, or “goal box.” Schachtman and his research team, including Jennifer Walker, a graduate student in psychology, and Agnes Simonyi, research associate professor in biochemistry, watched the mice to determine whether or not they could find the goal box, demonstrating memory and cognition.
In the second test, small “nestlets,” or squares containing materials to create nests, were placed in the habitats for different groups of mice. A day later, nests were scored based on shape and the amount of material used.
“Mice exhibiting symptoms of the disease had nests that were poorly formed or erratic,” said Schachtman. “Further, we found that mice with Alzheimer’s symptoms, much like people, can be apathetic about their habitat, or have forgotten how to ‘nest’ appropriately.”
Researchers then administered EGCG in the drinking water of the mice and gave them access to running or exercise wheels. After re-administering the maze and nesting tests, they found remarkable improvements in the cognitive function and retention in the Alzheimer’s affected mice that were given EGCG and were allowed to exercise.
Finally, a team of biochemists led by Grace Sun, professor emerita of biochemistry in the School of Medicine and the College of Agriculture, Food and Natural Resources at MU, and including Walker and Deepa Ajit, a postdoctoral fellow, analyzed mouse brain tissues to determine the effects of EGCG and exercise on A-beta levels in affected regions of the brain.
“Oral administration of the extract, as well as voluntary exercise, improved some of the behavioral manifestations and cognitive impairments of Alzheimer’s,” said Sun, who also serves as the director of the Alzheimer’s Disease Program at MU funded by the National Institutes of Health. “We also are excited to see a decrease in A-beta levels in the brains of the affected mice as well as improvements in behavior deficits in mice with AD.”
Consumption of natural products as potential remedies to prevent and treat diseases and to maintain human health is an ancient one, said Sun. Future studies of green tea extracts and other botanicals, also known as nutraceuticals, are being explored at MU and through collaborations with other international institutions.
Public Release: 7-May-2015
Strong statin-diabetes link seen in large study of Tricare patients
Increased diabetes risk for those on cholesterol-lowering drugs
Veterans Affairs Research Communications
In a database study of nearly 26,000 beneficiaries of Tricare, the military health system, those taking statin drugs to control their cholesterol were 87 percent more likely to develop diabetes.
The study, reported online April 28, 2015, in the Journal of General Internal Medicine, confirms past findings on the link between the widely prescribed drugs and diabetes risk. But it is among the first to show the connection in a relatively healthy group of people. The study included only people who at baseline were free of heart disease, diabetes, and other severe chronic disease.
“In our study, statin use was associated with a significantly higher risk of new-onset diabetes, even in a very healthy population,” says lead author Dr. Ishak Mansi. “The risk of diabetes with statins has been known, but up until now it was thought that this might be due to the fact that people who were prescribed statins had greater medical risks to begin with.”
Mansi is a physician-researcher with the VA North Texas Health System and the University of Texas Southwestern in Dallas.
In the study, statin use was also associated with a “very high risk of diabetes complications,” says Mansi. “This was never shown before.” Among 3,351 pairs of similar patients–part of the overall study group–those patients on statins were 250 percent more likely than their non-statin-using counterparts to develop diabetes with complications.
Statin users were also 14 percent more likely to become overweight or obese after being on the drugs.
Mansi points out that other studies have arrived at a similar finding through different research methods.
The study also found that the higher the dose of any of the statins, the greater the risk of diabetes, diabetes complications, and obesity.
A key strength of Mansi’s study was the use of a research method known as propensity score matching. Out of the total study population, the researchers chose 3,351 statin users and paired them with non-users who were very similar, at baseline, based on array of 42 health and demographic factors. The only substantial difference, from a research standpoint, was the use of statins. This helped the researchers isolate the effects of the drugs.
“This approach helps us to make comparisons that are fair and balanced,” says Mansi.
On a wider scale, looking at the overall comparison between the study’s roughly 22,000 nonusers and 4,000 users, and statistically adjusting for certain factors, the researchers found a similar outcome: Users of statins were more than twice as likely to develop diabetes.
The researchers examined patient records for the period between October 2003 and March 2012.
About three-quarters of the statin prescriptions in Mansi’s data were for simvastatin, sold as Zocor.
Mansi stresses that the study doesn’t definitively show that statins cause diabetes, nor does it mean people should stop using the drugs, which are widely prescribed to help people lower their cardiac risk factors.
“No patient should stop taking their statins based on our study, since statin therapy is a cornerstone in treatment of cardiovascular diseases and has been clearly shown to lower mortality and disease progression,” he says. “Rather, this study should alert researchers, [clinical] guideline writers, and policymakers that short-term clinical trials might not fully describe the risks and benefits of long-term statin use for primary prevention.”
Primary prevention refers to warding off disease in the first place.
Mansi urges further trials, similar to his group’s, to better understand the long-term effects of statin use.
Overall, besides driving further research, Mansi says he hopes the results will help inform conversations between patients and providers about the risks and benefits of statins.
“I myself am a firm believer that these medications are very valuable for patients when there are clear and strict indications for them,” he says. “But knowing the risks may motivate a patient to quit smoking, rather than swallow a tablet, or to lose weight and exercise. Ideally, it is better to make those lifestyle changes and avoid taking statins if possible.”
Public Release: 7-May-2015
Naturally occurring amino acid could improve oral health
ANN ARBOR — Arginine, a common amino acid found naturally in foods, breaks down dental plaque, which could help millions of people avoid cavities and gum disease, researchers at the University of Michigan and Newcastle University have discovered.
Alexander Rickard, assistant professor of epidemiology at the U-M School of Public Health, and colleagues, discovered that in the lab L-arginine — found in red meat, poultry, fish and dairy products, and is already used in dental products for tooth sensitivity–stopped the formation of dental plaque.
“This is important as bacteria like to aggregate on surfaces to form biofilms. Dental plaque is a biofilm,” Rickard said. “Biofilms account for more than 50 percent of all hospital infections. Dental plaque biofilms contribute to the billions of dollars of dental treatments and office visits every year in the United States.”
Dental biofilms are the culprits in the formation of dental caries (cavities), gingivitis and periodontal disease. Surveys indicate that nearly 24 percent of adults in the United States have untreated dental caries, and about 39 percent have moderate-to-severe periodontitis, a number that rises to 64 percent for those over age 65.
Most methods for dental plaque control involve use of antimicrobial agents, such as chlorhexidine, which are chemicals aimed at killing plaque bacteria, but they can affect sense of taste and stain teeth. Antimicrobial treatments have been the subject of debate about overuse in recent years.
Pending further clinical trials to verify their lab findings, the researchers said L-arginine could take the place of the current plaque-controlling biocide substances including chlorhexidine and other antimicrobials.
“At present, around 10-to-15 percent of adults in the Western world have advanced periodontitis, which can lead to loose teeth and even the loss of teeth. Therefore, there is a clear need for better methods to control dental plaque,” said Nick Jakubovics, a lecturer at Newcastle University’s School of Dental Sciences.
Their findings are reported in the current issue of PLOS ONE.
The mechanism for how L-arginine causes the disintegration of the biofilms needs further study, the researchers said. It appears arginine can change how cells stick together, and can trigger bacteria within biofilms to alter how they behave so that they no longer stick to surfaces, they said.
In conducting their research, team members used a model system they introduced in 2013 that mimics the oral cavity. The researchers were able to grow together the numerous bacterial species found in dental plaque in the laboratory, using natural human saliva.
“Other laboratory model systems use one or a small panel of species,” Rickard said. “Dental plaque biofilms can contain tens to hundreds of species, hence our model better mimics what occurs in the mouth, giving us great research insight.”
Public Release: 7-May-2015
Antioxidant effects of coffee by-products 500 times greater than vitamin C
Coffee silverskin (the epidermis of the coffee bean) is usually removed during processing, after the beans have been dried, while the coffee grounds are normally directly discarded.
University of Granada
It has traditionally been assumed that these by-products – coffee grounds and coffee silverskin, have few practical uses and applications. Spent coffee grounds are sometimes employed as homemade skin exfoliants or as abrasive cleaning products. They are also known to make great composting agents for fertilizing certain plants. But apart from these limited applications, coffee by-products are by and large deemed to be virtually useless. As such, practically all of this highly contaminating ‘coffee waste’ ends up in landfills across the globe and has a considerable knock-on effect on the environment.
However, a UGR research team led by José Ángel Rufíán Henares set out to determine the extent to which these by-products could be recycled for nutritional purposes, thereby reducing the amount of waste being generated, as well as benefitting coffee producers, recycling companies, the health sector, and consumers.
In an article published in the academic journal Food Science and Technology, the researchers demonstrate the powerful antioxidant and antimicrobial properties of the coffee grounds and silverskin, which are highly rich in fibre and phenols. Indeed, their findings indicate that the antioxidant effects of these coffee grounds are 500 times greater than those found in vitamin C and could be employed to create functional foods with significant health benefits.
Moreover, Professor Rufián Henares points out: “They also contain high levels of melanoidins, which are produced during the roasting process and give coffee its brown colour. The biological properties of these melanoidins could be harnessed for a range of practical applications, such as preventing harmful pathogens from growing in food products.” However, he also adds: “If we are to harness the beneficial prebiotic effects of the coffee by-products, first of all we need to remove the melanoidins, since they interfere with such beneficial prebiotic properties.”
The researchers conclude that processed coffee by-products could potentially be recycled as sources of new food ingredients. This would also greatly diminish the environmental impact of discarded coffee by-products.
The Ministry of Economics and Finance has recently allocated a new research project to the team under the ‘State R&D programme’, in order to enable them to conduct further studies in the area and re-assess the potential value of coffee by-products.
Public Release: 12-May-2015
Prenatal exercise lowers risks of C-sections, higher birth weights
University of Alberta
Pregnant women who exercise can significantly lower the risk of undergoing Caesarean sections and giving birth to large babies, a University of Alberta study has found.
Prenatal exercise has been suggested to be a means to prevent childhood obesity through a “normalization” in birth weight (ie. reducing the risk of having a large baby at birth). University of Alberta researchers conducted a meta-analysis to analyze 28 randomized control studies encompassing 5,322 women that looked at the influence of maternal exercise on baby outcomes.
“We found that women who exercised had a 31 per cent reduction in the risk of having a large baby without changing the risk of having a small baby or an earlier baby,” said lead researcher Margie Davenport, an assistant professor in the Faculty of Physical Education and Recreation. “Further, the risk of having a Caesarean section was reduced by 20 per cent.” The findings, recently published in Obstetrics & Gynecology, are important because babies who are born large tend to be heavier as children and into adulthood
Public Release: 12-May-2015
Campaign to reduce the harms of too much medicine comes to the UK
· Patients should be encouraged to ask if tests are really needed
· Doctors should discuss potential harms of treatment with patients
· Experts will develop lists of common practices that should be stopped
A US initiative to get doctors to stop using interventions with no benefit is being launched in the UK this week.
The Academy of Medical Royal Colleges, which represents all medical royal colleges in the UK, is launching a Choosing Wisely programme in partnership with specialty organisations, including The BMJ, to help tackle the threat to human health posed by overdiagnosis and the waste of resources on unnecessary care.
In The BMJ today, Dr Aseem Malhotra and colleagues set out the aims of the project and explain why doing nothing can often be the best approach.
Unnecessary care occurs when people are diagnosed and treated for conditions that will never cause them harm, and there’s growing evidence that many people are overdiagnosed and overtreated for a wide range of conditions such as prostate and thyroid cancers, asthma, and chronic kidney disease.
Participating organisations will be asked to identify five tests or procedures commonly used in their field, whose necessity should be questioned and whose risks and benefits should be discussed with patients before using them.
These will be compiled into lists, and the “top five” interventions for each specialty should not be used routinely or at all.
So far, more than 60 US specialist societies have joined the Choosing Wisely initiative, say the authors. It has also been adopted by other countries, including Australia, Germany, Italy, Japan, Netherlands and Switzerland – a clear sign that wasteful medical practices are a problem for all health systems.
A culture of “more is better,” where the onus is on doctors to “do something” at each consultation has bred unbalanced decision making, argue the authors. “This has resulted in patients sometimes being offered treatments that have only minor benefit and minimal evidence despite the potential for substantial harm and expense.”
This culture threatens the sustainability of high quality healthcare and stems from defensive medicine, patient pressures, biased reporting in medical journals, commercial conflicts of interest, and lack of understanding of health statistics and risk, they add.
Rather than focusing on a system of payment by results – which encourages doctors and hospitals to do more – they suggest that guideline committees “should increasingly turn their efforts towards the production of tools that help clinicians to understand and share decisions on the basis of best evidence.”
They acknowledge that shared decision making “does not guarantee lower resource use” and that reducing wasteful and harmful healthcare “will require commitment from both doctors and patients, in addition to objective evidence of effectiveness.”
But they say it is time for action “to translate the evidence into clinical practice and truly wind back the harms of too much medicine.”
Public Release: 13-May-2015
Infant antibiotic use linked to adult diseases
New study may lead to recommendations for antibiotic usage and a clinical test for measuring gut microbe development in children
University of Minnesota
A new study led by researchers at the University of Minnesota has found a three-way link among antibiotic use in infants, changes in the gut bacteria, and disease later in life. The imbalances in gut microbes, called dysbiosis, have been tied to infectious diseases, allergies and other autoimmune disorders, and even obesity, later in life.
The study, led by Biomedical Informatics and Computational Biology program graduate student fellow Pajau Vangay, also developed a predictive model with potential clinical importance for measuring healthy development of bacteria in the gut of young children. The findings were published today in the scientific journal Cell Host & Microbe.
Antibiotics are by far the most common prescription drugs given to children. They account for about one-fourth of all medications prescribed to children, with a third of these prescriptions considered unnecessary. Other studies have shown profound short- and long-term effects of antibiotics on the diversity and composition of the bacteria in our bodies, called our microbiome.
“Diseases related to metabolism and the immune system are increasing dramatically, and in many cases we don’t know why,” said the study’s senior author Dan Knights, a computational biologist and assistant professor in the University of Minnesota’s Department of Computer Science and Engineering and Biotechnology Institute. “Previous studies showed links between antibiotic use and unbalanced gut bacteria, and others showed links between unbalanced gut bacteria and adult disease. Over the past year we synthesized hundreds of studies and found evidence of strong correlations between antibiotic use, changes in gut bacteria, and disease in adulthood.”
Knights and his colleagues developed a framework to map how antibiotics may be acting in the gut to cause disease later in life. In the case of allergies, for example, the use of antibiotics may eradicate key gut bacteria that help immune cells mature. These cells would have been essential for keeping the immune system at bay when confronted with allergens. Even if these bacteria return, the immune system remains impaired. Related to obesity, antibiotic-induced changes in the gut microbiota resulted in increased levels of short-chain fatty acids that affect metabolism.
The study also examined the development of bacteria in the gut. Researchers demonstrated that an infant’s age could be predicted within 1.3 months based on the maturity of their gut bacteria. This finding could lead to a clinical test and interventions for children whose microbiome is developmentally delayed due to antibiotics or other factors.
“We think these findings help develop a roadmap for future research to determine the health consequences of antibiotic use and for recommendations for prescribing them,” Knights said. “The clinical test we demonstrated would also allow us to think about interventions at an early age.”
Public Release: 13-May-2015
Anemia distorts regular method of diabetes diagnosis and questions its reliability
The use of glycated haemoglobin (sugar-bound haemoglobin, or HbA1c) is now in almost universal use to assist doctors in the diagnosis of type 2 diabetes. However new research published in Diabetologia (the journal of the European Association for the Study of Diabetes) highlights how anaemia–a common condition in the general population, especially in women–can lead to a false diagnosis of diabetes based on HbA1c, when a person’s blood sugar control is actually normal. The research is by Dr Emma English, University of Nottingham, UK, and colleagues.
In recent years, there has been a move towards the use of HbA1c for the diagnosis of type 2 diabetes (T2D). The World Health Organization (WHO) and the American Diabetes Association (ADA) have both advocated the use of HbA1c for diagnosing this condition, at a value of 6.5% (48 mmol/mol). In the UK and most of Europe, the same cut off is used.
Following the recommendations of WHO to use HbA1c as the diagnostic method for T2D, the UK (via its government’s Department of Health) issued expert guidance stating that one of the major issues affecting this technique was anaemia, which affects the levels of haemoglobin (Hb) in the blood. WHO defines anaemia in adults as 120 g/l Hb in non-pregnant women and 130 g/l in men. With approximately 29% of non-pregnant women worldwide having anaemia (latest estimate from 2011), this translates to a significant number of people where the use of HbA1c for diagnosis of diabetes is unsuitable. The latest WHO estimate for anaemia prevalence in men was 13%, likely to be higher in elderly men, although data are scarce.
In this systematic review, the authors aim to address the above questions by assessing the available evidence on the impact of abnormalities of erythrocyte (red blood cell) indices and anaemia on HbA1c levels around the WHO/ADA diagnostic cut off point of 48 mmol/mol (6.5%).The review of research between 1990 and 2014 included studies which had at least one measurement of HbA1c and glucose, and at least one index of anaemia involving non-pregnant adults not diagnosed with diabetes. The authors identified 12 studies suitable for inclusion, the majority of which focused on iron deficiency anaemia and, in general, demonstrated that the presence of iron deficiency with or without anaemia led to an increase in HbA1c values compared with controls, with no corresponding rise in blood glucose, thus rendering any diagnosis of diabetes in such individuals unreliable without further tests.
The authors say: “HbA1c is likely to be affected by iron deficiency and iron deficiency anaemia with a spurious increase in HbA1c values. This may lead to confusion when diagnosing diabetes using HbA1c. This review clearly identifies the need for more evidence, especially in identifying the types and degrees of anaemia likely to have significant impact on the reliability of HbA1c.”
While further evidence is gathered, the authors make several recommendations regarding clinical practice, including:
1. During monitoring of people with diabetes, when glucose and HbA1c measurements give different results, consider abnormalities related to anaemia or iron deficiency.
2. Iron deficiency, as well as iron deficiency anaemia, may be sufficient to cause a change in HbA1c values; this is highly relevant in women of childbearing age.
3. If abnormalities such as anaemia are identified, consider correction of the abnormality (for example using iron supplementation if caused by iron deficiency) before using HbA1c for diagnosis or monitoring. The studies included in this review suggest that it may take up to 6 months after treatment is initiated to normalise haemoglobin levels.
Calling for more research in view of the relatively small number of studies they were able to include in their review, the authors conclude: “The key questions that are still to be answered are whether anaemia and red blood cell abnormalities will have a significant impact on the diagnosis of diabetes using HbA1c in the general population–something that is now widely performed.”
Public Release: 14-May-2015
Link between vitamin E and exposure to air pollution
King’s College London
A new study from King’s College London and the University of Nottingham has found an association between the amount of vitamin E in the body, exposure to particulate pollution and lung function. The paper adds to growing evidence from previous studies suggesting that some vitamins may play a role in helping to protect the lungs from air pollution. Although the new study did not specifically demonstrate a protective effect, it is the first to show a clear link between vitamin E concentrations in the blood and exposure to fine particulate pollution in the general population.
Particulate matter (PM) is one of the main air pollutants thought to be damaging to human health. Previous studies have reported an inverse association between exposure to PM and lung function. However, the underlying mechanisms linking ambient air pollution to lung function are not yet fully understood.
The new data, published in the American Journal of Respiratory and Critical Care Medicine, looked at the association between lung function and a set of metabolites – chemical signatures circulating in the blood – and between these metabolites and exposure to PM10 and PM2.5 (particles smaller than 10 and 2.5 microns, respectively) determined as the concentrations of these pollutants at the participants’ residence.
Two-hundred and eighty metabolites were measured in the blood of over 5,500 fasting volunteers from the TwinsUK study who had also undergone a spirometry or lung test. This test determines the lung’s forced vital capacity (FVC), a measure of the amount of air you can exhale with force after you inhale as deeply as possible, and forced expiratory volume (FEV), a measure of the amount of air you can exhale with force in one breath.
A subset of this group of twins – around 500 participants – living in the Greater London area also had their long-term exposure to PM estimated from their postcode using computer modelling of air pollution across London. Participants completed a medical history and lifestyle questionnaire, including questions on whether they took vitamin supplements.
The profiling revealed 13 metabolites significantly associated with FVC, 10 of which were also identified for FEV. Of the metabolites associated with lung function, eight were also significantly associated with exposure to both PM2.5 and PM10. In all eight instances, a higher exposure to PM was found to correlate with lower levels of the metabolite and a lower FEV.
Among the eight metabolites identified were two well-known antioxidants, alpha tocopherol or a-tocopherol (biologically active form of Vitamin E) and a metabolite of ascorbic acid (Vitamin C) known as threonate. Both compounds have previously been linked to lung function as well as exposure to PM.
The strongest association both with PM2.5 and FEV was seen with vitamin E. Individuals with a higher exposure to PM2.5 had significantly lower levels of alpha-tocopherol and also had lower lung function. These findings provide further evidence supporting the theory that PM damages lungs through oxidative attack while alpha-tocopherol acts to minimise oxidative injury.
Dr Ana Valdes, Reader at the University of Nottingham and co-author of the study, explained: ‘Our work builds on a number studies exploring whether some vitamins can counteract the negative effect on lungs caused by air pollution. More work is needed to establish whether antioxidant supplements do indeed provide protection to the lungs in the general population.’
Professor Frank Kelly, Head of the Environmental Research Group at King’s College London and co-author of the study, said: ‘These new findings are consistent with previous reports which observed lower levels of vitamin E in people with lung conditions such as asthma. However, we do not yet fully understand which types of particulate pollution specifically damage the lungs or which vitamins best interfere with this pathway to reduce the level of damage.’
Public Release: 14-May-2015
30 minutes of physical activity 6 days a week linked to 40 percent lower risk of death in elderly men
Impact on health as good as giving up smoking, suggest researchers
Thirty minutes of physical activity–irrespective of its intensity–6 days a week is linked to a 40% lower risk of death from any cause among elderly men, finds research published online in the British Journal of Sports Medicine.
Boosting physical activity levels in this age group seems to be as good for health as giving up smoking, the findings suggest.
The researchers base their findings on people taking part in the Oslo Study, which invited almost 26,000 men born between 1923 and 1932 for a health check in 1972-3 (Oslo I).
Some 15,000 agreed. Their height, weight, cholesterol and blood pressure were all assessed, and they were asked whether they smoked.
They were also asked to respond to a validated survey (Gothenburg questionnaire) on their weekly leisure time physical activity levels.
These were categorised as sedentary (watching TV/reading); light (walking or cycling, including to and from work for at least 4 hours a week); moderate (formal exercise, sporting activities, heavy gardening for at least 4 hours a week); and vigorous (hard training or competitive sports several times a week).
Some 6000 of the surviving men repeated the process in 2000 (Oslo II) and were monitored for almost 12 years to see if physical activity level over time was associated with a lowered risk of death from cardiovascular disease, or any cause, and if its impact were equivalent to quitting smoking.
During the monitoring period, 2154 out of the 5738 men who had gone through both health checks died.
The analysis indicated that less than an hour a week of light physical activity was not associated with any meaningful reduction in risk of death from any cause. But more than an hour was linked to a 32% to 56% lower risk.
Less than an hour of vigorous physical activity, on the other hand, was linked to a reduction in risk of between 23% and 37% for cardiovascular disease and death from any cause.
The more time spent doing vigorous exercise the lower the risk seemed to be, falling by between 36% and 49%.
And men who regularly engaged in moderate to vigorous physical activity during their leisure time lived five years longer, on average, than those who were classified as sedentary.
Factoring in that the risk of death from heart disease/stroke rises with age, made only a slight difference to the results.
Overall, these showed that 30 minutes of physical activity–of light or vigorous intensity–6 days a week was associated with a 40% lower risk of death from any cause.
The impact would seem to be as good for health as quitting smoking among this age group, suggest the researchers.
This is an observational study so no definitive conclusions can be drawn about cause and effect, and the researchers point out that only the healthiest participants in the first wave of the study took part in the second wave, which may have lowered overall absolute risk.
But the differences in risk of death between those who were inactive and active were striking, even at the age of 73, they suggest.
More effort should go into encouraging elderly men to become more physically active, with doctors emphasising the wide range of ill health that could be warded off as a result, conclude the researchers.