177 21 MAR 2014 / Compiled by Ralph Turchiano
• Detailed research references and further affiliations on each article are posted at http://www.healthreserachreport.me .
In This Issue:
- IBS and bloating: When the gut microbiota gets out of balance
- A tricky balancing act: Antibiotics versus the gut microbiota
- Discrepancies between trial results reported on clinical trial registry and in journals
- Study suggests potential association between soy formula and seizures in children with autism
- Tequila plant is possible sweetener for diabetics — helps reduce blood sugar, weight
- Honey is a new approach to fighting antibiotic resistance: How sweet it is!
- Primary androgen deprivation therapy ineffective for most men with early prostate cancer
- The precise reason for the health benefits of dark chocolate: Mystery solved
- Fried foods may interact with genes to influence body weight, say experts
- Stimulants Used to Treat ADHD Influence BMI Growth Patterns Through Childhood With a BMI Rebound in Late Adolescence
- New guidelines deem 13 million more Americans eligible for statins
- Studies of gut flora in infants and toddlers could lead to better health
IBS and bloating: When the gut microbiota gets out of balance
(March 10, 2014) Irritable bowel syndrome (IBS) belongs to the most widespread diseases in Western countries, causing up to sixty per cent of the workload of gastrointestinal physicians. One of the most frequent symptoms of IBS is bloating, which reduces quality of life considerably as patients perceive it as particularly bothersome. For quite a long time, IBS was believed to be a primarily psychological condition.
“Contrary to this view, recent findings suggest that IBS is linked to clearly detectable gut microbiota alterations. Additionally, bloating can be related to specific kinds of diet, thus opening up promising paths towards an efficient disease management,” says Professor Giovanni Barbara (University of Bologna, Italy).
This was one of the topics presented at the Gut Microbiota for Health World Summit in Miami, FL, USA. On March 8-9, 2014, internationally leading experts discussed the latest advances in gut microbiota research and its impact on health.
IBS is one of the most common gastrointestinal disorders, causing several symptoms, which include abdominal pain, bowel movements that cause discomfort, and — in nearly all patients — bloating. IBS affects up to 20 percent of the population in Western countries. This condition represents up to 10 percent of the workload of family physicians and up to 60 per cent of that of gastroenterology practitioners. Within the range of IBS troubles, it is bloating that bothers patients most.
A microbiota-based condition
For quite a long time, not only bloating, but IBS in general was frequently perceived as a mainly psychological condition, mostly affecting young, predominantly female and anxious patients with no detectable abnormalities in their bowels. Consequently, the disease burden was often attributed to an imaginary disorder, and the treatment was far from satisfactory.
“Thanks to new diagnostic insights and a rapidly growing knowledge about the role and function of the microbial communities living inside our guts, our view on IBS and its causes has changed considerably,” says Prof. Barbara, President of the European Society of Neurogastroenterology and Motility (ESNM). According to him, there is a lot of evidence showing that IBS is associated with an imbalanced composition of the gut microbiota. This means that the system of checks and balances between beneficial and potentially harmful bacteria, which characterizes a healthy gut microbiota, is disturbed in IBS patients.
“Probably the best example of this interaction is the discovery that IBS symptoms develop in up to 10 percent of previously healthy subjects after a single episode of gastroenteritis caused by an infection through bacterial pathogens like Salmonella, Shighella or Campylobacter, which can severely disrupt the microbiota balance,” says Prof. Barbara. An additional problem results from the fact that not only infections, but also the antibiotics that are used as a remedy, may increase the risk for IBS, as they, too, can alter the gut microbiota in a negative way.
Nutrition is key
Another important factor is nutrition. Food that is rich in carbohydrates, particularly fiber, tends to produce larger amounts of gas than a diet without these ingredients. In some individuals, this might lead to repeated bloating and flatulence. The potentially negative impact of this kind of nutrition applies in particular to individuals who already suffer from IBS. Recent studies show that such a “flatulogenic” diet (for example, bread, cereals and pastries made of whole wheat, and beans, soy beans, corn, peas, Brussels’ sprouts, cauliflower, broccoli, cabbage, celery, onions, leek, garlic, artichokes, figs, peaches, grapes and prunes) induces profound changes in the microbiota of IBS patients, thus prolonging and increasing the symptoms. However, at the same time, the gut microbiota of healthy subjects remained stable and unaffected by this kind of diet.1
“On the other hand, we now know for sure that diets containing low fiber content improve these symptoms significantly. Recent research results suggest that, compared to a normal Western diet, a diet low in so-called FODMAPs (fermentable oligosaccharides, disaccharides, monosaccharides and polyols) reduces symptoms of IBS, including bloating, pain and passage of wind,” says Prof. Barbara.
Another interesting observation Prof. Barbara points to is that those IBS patients who have several clear-cut gut symptoms have also more profound changes in their gut microbiota, as compared to other patients whose bowel physiology is less disturbed, but instead combined with mood disorders. This suggests that the troubles of the second group are more socially grounded and mood-related, whereas the condition of the patients belonging to the first group is predominantly physiologically based — IBS proper, so to speak.
What further developments can doctors and patients expect? “It is amazing to see how quickly gut microbiota research has gained center stage within gastroenterology in the course of the past few years,” says Prof. Barbara. “This is due to its crucial role not only for IBS, but for gastrointestinal health in general. In order to further improve diagnosis and treatment, we have to identify more of the various functions of the intestinal bacteria. With regard to clinical applications, bacterial functions are even more important than their types.”
A tricky balancing act: Antibiotics versus the gut microbiota
(March 10, 2014) Antibiotics are valuable, potentially life-saving tools that have significantly reduced human morbidity and mortality. Unfortunately, antibiotics may also have unintended consequences from their off-target effects that may increase the risk of many long-term conditions. Recent epidemiologic studies have detected a possible link between antibiotic use in childhood and weight gain1 — with disruption to the normal gut microbiota considered the most likely cause.
“Infancy is an important time in the development of the human microbiota and these studies provide evidence that early exposure to antibiotics may disrupt the early-life microbiota and lead to changes in growth and metabolic development,” says Dr Laura Cox (New York University, USA). “In animal studies, we are carefully trying to understand how the intestinal microbiota influences body composition and metabolism and what impact antibiotics might have.”
Her talk was one of the topics presented at the Gut Microbiota for Health World Summit in Miami, FL, USA. On March 8-9, 2014, internationally leading experts discussed the latest advances in gut microbiota research and its impact on health.
Antibiotics came into widespread use after the Second World War, with substantial public health benefits. Use of antibiotics has increased markedly, with infants and children averaging one course of antibiotics every year. Longstanding concerns over the broadening and sometimes inappropriate use of antibiotics (e.g. self-medication, use in viral infections, empirical use of broad-spectrum agents in cancer patients with neutropenia) have focussed primarily on the development of bacterial resistance, but it seems clear that antibiotics can also affect the bacteria we need in our guts, as well as those we want to eradicate. This, it seems, could have serious long-term consequences to our health.
Microbiota beyond the gut
The intestinal microbiota, composed of trillions of microbial cells, undertakes many vital immune, hormonal and metabolic functions. Disruption to normal colonization — through the over-use of antibiotic therapy — could, it has been suggested, be fueling the dramatic increase in conditions such as obesity, type 1 diabetes, inflammatory bowel disease, allergies and asthma, which have more than doubled in prevalence in many populations. Evidence is also mounting that microbiota resilience decreases with each subsequent course of antibiotics2 and that, once disrupted, the normal microbiota may never recover completely or it may be replaced by resistant organisms.3,4
“We are just beginning to understand the roles that the intestinal microbiota plays in normal growth and development,” says Dr Cox, “and further studies in both humans and experimental animal models are needed to characterize the potential impact of antibiotics on the microbiota and host physiology.”
Body composition and metabolism
The spotlight has recently fallen on the role of the gut microbiota in normal growth and development, with scientists now concerned that altering the microbial balance in the gut with antibiotics may lead to weight gain. Low doses of antibiotics have been used for decades in the agricultural industry to promote weight gain in farm animals, and researchers have reported similar changes in body fat and tissue composition in laboratory animals given low-dose antibiotics.5 Studies are currently underway using sub-therapeutic antibiotic treatment as a tool to disrupt the microbial ecosystem and alter host body composition with the aim of identifying organisms within the microbiota that could either promote or protect against obesity.
“We are working hard to understand the link between antibiotic exposure, gut microbiota and body composition,” explains Dr Cox. “Ultimately, our aim is to develop microbiota restoration strategies following antibiotic treatment to rebalance the gut microbiota and promote healthy growth and development.”
The microbial communities that reside in the human gut and their impact on human health and disease are one of the most exciting new areas of research today. To address the most recent advances in this rapidly developing field, scientists and health-care professionals from all over the world came together at the Gut Microbiota for Health World Summit in Miami, Florida, USA, on March 8-9, 2014. The meeting was hosted by the Gut Microbiota & Health Section of the European Society of Neurogastroenterology and Motility (ESNM) and the American Gastroenterological Association (AGA) Institute, with the support of Danone.
Discrepancies between trial results reported on clinical trial registry and in journals
During a one year period, among clinical trials published in high-impact journals that reported results on a public clinical trial registry (ClinicalTrials.gov), nearly all had at least 1 discrepancy in the study group, intervention, or results reported between the 2 sources, including discrepancies in the designated primary end points for the studies, according to a study in the March 12 issue of JAMA.
The 2007 Food and Drug Administration (FDA) Amendments Act expanded requirements for ClinicalTrials.gov, mandating results reporting within 12 months of trial completion for all FDA-regulated medical products. “To our knowledge, no studies have examined reporting and accuracy of trial results information. Accordingly, we compared trial information and results reported on ClinicalTrials.gov with corresponding peer-reviewed publications,” write Jessica E. Becker, A.B., of the Yale University School of Medicine, New Haven, Conn., and colleagues.
The researchers identified 96 trials reporting results on ClinicalTrials.gov that were published in high-impact journals from July 1, 2010 and June 30, 2011. For 70 trials (73 percent), industry was the lead funder. Cohort, intervention, and efficacy end point information was reported for 93 percent to 100 percent of trials in both sources. However, 93 of 96 trials had at least one discordance among reported trial information or reported results.
Among trials reporting each cohort characteristic (enrollment and completion, age/sex demographics) and trial intervention information, discordance ranged from 2 percent to 22 percent and was highest for completion rate and trial intervention, for which different descriptions of dosages, frequencies, or duration of intervention were common.
Among 132 primary efficacy end points described in both sources, results for 23 percent could not be compared and 16 percent were discordant. The majority (n = 15) of discordant results did not alter trial interpretation, although for 6 the discordance did. Overall, 52 percent of primary efficacy end points were described in both sources and reported concordant results.
Among 619 secondary efficacy end points described in both sources, results for 37 percent could not be compared, whereas 9 percent were discordant. Overall, 16 percent of secondary efficacy end points were described in both sources and reported concordant results.
“… because articles published in high-impact journals are generally the highest-quality research studies and undergo more rigorous peer review, the trials in our sample likely represent best-case scenarios with respect to the quality of results reporting. Our findings raise questions about accuracy of both ClinicalTrials.gov and publications, as each source’s reported results at times disagreed with the other. Further efforts are needed to ensure accuracy of public clinical trial result reporting efforts.”
Study suggests potential association between soy formula and seizures in children with autism
MADISON — A University of Wisconsin-Madison researcher has detected a higher rate of seizures among children with autism who were fed infant formula containing soy protein rather than milk protein.
The study found excess seizures among girls and in the total sample of 1,949 children. The soy-seizure link reached borderline significance among boys, who comprised 87 percent of the children described in the database under study.
Seizures — caused by uncontrolled electrical currents in the brain — occur in many neurological disorders including epilepsy, Alzheimer’s disease, Down syndrome and autism.
About 25 percent of infant formula sold in the United States is based on soy protein.
Study author Cara Westmark, a senior scientist in the UW-Madison department of neurology, says her investigation was sparked by mouse studies of a drug that, it was hoped, would inhibit seizures by blocking signals that excite nerve cells. “It was pure serendipity that we happened to look at soy,” she says.
To simplify the mouse study, she replaced the standard lab chow, which had a variable composition, with a diet containing purified ingredients. Unexpectedly, that diet reduced the rate of seizures by 50 percent compared to standard chow, Westmark says.
“We were intrigued that a dietary alteration was as effective as many medicines in reducing seizure incidence and wanted to pursue that finding,” she says. “We found that the main difference between the diets was the protein source. The standard diet was soy-based, while the purified diet was casein, or dairy, based.”
The mechanism of action is unknown, but Westmark points to the high level of plant-derived estrogens in soy products as a possible cause of the excess seizures.
People eat a lot of soy products, and when Westmark began to look for the effect in people, she decided to focus on infants, who may consume nothing but formula. Knowing that people with autism have a higher rate of seizures, Westmark turned to a database from the Simons Foundation Autism Research Initiative.
And that led to the new study, published today in the journal PLOS ONE, which showed that children with autism who were fed soy formula had 2.6 times as many febrile seizures as the children fed non-soy formula in the database. That means 4.2 percent of the soy group had a seizure associated with a fever, compared to 1.6 percent of the others.
To put it another way, the vast majority of both groups did not have seizures. “This is not saying that all autistic children who eat soy-based formula are going to develop seizures,” says Westmark.
And yet that increase is worrying, Westmark says. “The prevalence of autism is increasing and currently affects one American child in 88. Soy is a widespread ingredient in many food products and 25 percent of infant formulas are soy based, so this is something that needs to be studied. If the child is lactose intolerant, there are alternatives that a pediatrician can recommend.”
The study, Westmark says, was not the kind of randomized clinical trial that can prove causation. “We can say that we have a potential association between the use of soy-based formula and seizures in autistic children; we can’t say that this is cause and effect. We were fortunate to be granted access to the SFARI database, but it was not set up to answer the questions we were asking.”
Although it’s possible that seizures could also be more frequent among children who consume soy formula but do not have a developmental disability, “There is no data available at this time to support that,” Westmark says. Still, the study raises concerns, since seizures cause neurological damage and repeated seizures — epilepsy — can develop into a lifelong problem.
“This needs to be studied more thoroughly,” Westmark says. “If soy formula is lowering the threshold for seizures or increasing the incidence of seizures, we need to know that.”
Tequila plant is possible sweetener for diabetics — helps reduce blood sugar, weight
DALLAS, March 16, 2014 — A sweetener created from the plant used to make tequila could lower blood glucose levels for the 26 million Americans and others worldwide who have type 2 diabetes and help them and the obese lose weight, researchers said here today.
The main reason it could be valuable, they explained, is that agavins, a natural form of sugar found in the agave plant, are non-digestible and can act as a dietary fiber, so they would not raise blood glucose. Their report was part of the 247th National Meeting of the American Chemical Society (ACS), the world’s largest scientific society.
The meeting, attended by thousands of scientists, features more than 10,000 reports on new advances in science and other topics. Being held at the Dallas Convention Center and area hotels, it continues through Thursday.
“We have found that since agavins reduce glucose levels and increase GLP-1, they also increase the amount of insulin,” said Mercedes G. López, Ph.D. GLP-1 (glucagon-like peptide-1) is a hormone that slows the stomach from emptying, thereby stimulating production of insulin. She added, “Agavins are not expensive and they have no known side effects, except for those few people who cannot tolerate them.” In addition, agavins, like other fructans, which are made of the sugar fructose, are the best sugars to help support growth of healthful microbes in the mouth and intestines, she said.
López, who is with Centro de Investigación y de Estudios Avanzados, Biotechnology and Biochemistry Irapuato, Guanajuato, Mexico, also noted that agavins can help people feel fuller, which could help them eat less.
Agavins contain fructoses, which begs the question: Are agavins like high-fructose corn syrup, a processed sweetener that has gotten a lot of bad press recently? López pointed out that, indeed, high-fructose corn syrup is loaded with fructose sugars and, therefore, can raise blood sugar levels. But agavins are fructans, which are fructoses linked together in long, branched chains. The human body can’t use them in that configuration, so they don’t affect blood sugar, she explained. Agavins also sometimes get confused with agave nectar or agave syrup, which appears on many health-food store shelves. These products contain fructans that have been broken down into individual fructoses, so they are much more similar to high-fructose corn syrup.
Also, she and her team said agavins are better than artificial sweeteners, which are absorbed by the body and can cause side effects, like headaches. “One slight downside, however, is that agavins are not quite as sweet as their artificial counterparts,” she said.
Of course, the agave’s claim to fame is as the plant from which tequila is made. López explained that agavins are the only carbohydrates used to produce the drink. All ethanol in tequila comes from the fermentation of glucose and fructose generated after agave pines are cooked. But because the agavins are converted to ethanol, agavins are not found in the finished product.
López said that in the study, her team fed a group of mice a standard diet and added agavins to their daily water. They weighed the mice daily and checked their glucose blood levels weekly. Most mice that drank agavins ate less, lost weight and their blood glucose levels decreased when compared to other sweeteners such glucose, fructose, sucrose, agave syrup and aspartame.
“This study represents the first attempt to evaluate agavins as sweeteners in spite of their lower sweetness compared to sugar,'” she said.
Honey is a new approach to fighting antibiotic resistance: How sweet it is!
DALLAS, March 16, 2014 — Honey, that delectable condiment for breads and fruits, could be one sweet solution to the serious, ever-growing problem of bacterial resistance to antibiotics, researchers said here today.
Medical professionals sometimes use honey successfully as a topical dressing, but it could play a larger role in fighting infections, the researchers predicted. Their study was part of the 247th National Meeting of the American Chemical Society (ACS), the world’s largest scientific society.
The meeting, attended by thousands of scientists, features more than 10,000 reports on new advances in science and other topics. It is being held at the Dallas Convention Center and area hotels through Thursday.
“The unique property of honey lies in its ability to fight infection on multiple levels, making it more difficult for bacteria to develop resistance,” said study leader Susan M. Meschwitz, Ph.D. That is, it uses a combination of weapons, including hydrogen peroxide, acidity, osmotic effect, high sugar concentration and polyphenols — all of which actively kill bacterial cells, she explained. The osmotic effect, which is the result of the high sugar concentration in honey, draws water from the bacterial cells, dehydrating and killing them.
In addition, several studies have shown that honey inhibits the formation of biofilms, or communities of slimy disease-causing bacteria, she said. “Honey may also disrupt quorum sensing, which weakens bacterial virulence, rendering the bacteria more susceptible to conventional antibiotics,” Meschwitz said. Quorum sensing is the way bacteria communicate with one another, and may be involved in the formation of biofilms. In certain bacteria, this communication system also controls the release of toxins, which affects the bacteria’s pathogenicity, or their ability to cause disease.
Meschwitz, who is with Salve Regina University in Newport, R.I., said another advantage of honey is that unlike conventional antibiotics, it doesn’t target the essential growth processes of bacteria. The problem with this type of targeting, which is the basis of conventional antibiotics, is that it results in the bacteria building up resistance to the drugs.
Honey is effective because it is filled with healthful polyphenols, or antioxidants, she said. These include the phenolic acids, caffeic acid, p-coumaric acid and ellagic acid, as well as many flavonoids. “Several studies have demonstrated a correlation between the non-peroxide antimicrobial and antioxidant activities of honey and the presence of honey phenolics,” she added. A large number of laboratory and limited clinical studies have confirmed the broad-spectrum antibacterial, antifungal and antiviral properties of honey, according to Meschwitz.
She said that her team also is finding that honey has antioxidant properties and is an effective antibacterial. “We have run standard antioxidant tests on honey to measure the level of antioxidant activity,” she explained. “We have separated and identified the various antioxidant polyphenol compounds. In our antibacterial studies, we have been testing honey’s activity against E. coli, Staphylococcus aureus and Pseudomonas aeruginosa, among others.”
Primary androgen deprivation therapy ineffective for most men with early prostate cancer
WASHINGTON — A study of more than 15,000 men with early stage prostate cancer finds that those who received androgen deprivation as their primary treatment instead of surgery or radiation did not live any longer than those who received no treatment.
The research team, led by scientists at Georgetown Lombardi Comprehensive Cancer Center, say that the risks of serious adverse events associated with the treatment — which has been linked to impaired cognition, heart disease, diabetes and other disorders — “mitigates against any clinical or policy rationale for use of primary androgen deprivation therapy in these men.”
The findings, reported Monday in the Journal of Clinical Oncology, draw from cancer registries linked with extensive electronic medical records in three, large integrated health plans. The men included in the study had prostate cancer that had not spread beyond the organ (localized) and did not have surgery or radiation therapy, considered curative treatment.
Androgen deprivation therapy suppresses the production of testosterone, the male hormone said to fuel growth of prostate cancer. The therapy improves survival when given with radiation for later stages of disease, and is considered the standard of care for men who have metastatic prostate cancer. Effectiveness of primary androgen deprivation therapy (PADT) has not been established.
“This study is the most comprehensive study on the effectiveness of PADT for men who forgo radiation and surgery for their localized prostate cancer, and it tells us there is no strong reason to use it in most patients,” says the study’s lead investigator, Arnold Potosky, PhD, a professor of oncology and director of health services research at Georgetown Lombardi. “We found only a small survival benefit for primary androgen deprivation therapy compared to no therapy in men diagnosed with higher-risk localized prostate cancer.”
Use of primary androgen deprivation therapy for early stage prostate cancer is widespread. Despite the lack of randomized clinical trials to test its effectiveness, recent studies have reported it as the second most common treatment, after radiotherapy, for clinically localized prostate cancer among older men age 65 and older. The study did not compare androgen deprivation therapy directly to either surgery or radiation therapy, the two main curative treatment options for prostate cancer.
While the study did not probe the reasons why physicians prescribe the treatment in this setting, it was much more common in older men and those with higher risk of disease progression. Potosky speculates that men and their doctors may feel the treatment is a useful option to delay progression of prostate cancer for men who are not good candidates for, or who prefer to avoid, surgery or radiation due to their side-effects.
“Primary androgen deprivation therapy may be preferable to some men with early stage prostate cancer who would prefer to do something rather than watch and wait for further signs of progression to occur later and then need treatments,” Potosky adds. “However, using PADT by itself immediately after diagnosis in the hopes of limiting cancer’s progression does not extend survival, according to this study.”
The researchers are now using their database of 15,170 patients to examine rates of potential side effects from the treatment.
“Given the aging American population, more men are likely to be faced with prostate cancer so its is very important to understand the whether the risks of primary androgen deprivation therapy outweigh the survival benefit,” he says. “Ultimately, this is a decision for men and their doctors to make together, and we hope that our study provides some helpful information to guide these decisions.”
The precise reason for the health benefits of dark chocolate: Mystery solved
DALLAS, March 19, 2014 — The health benefits of eating dark chocolate have been extolled for centuries, but the exact reason has remained a mystery –– until now. Researchers reported here today that certain bacteria in the stomach gobble the chocolate and ferment it into anti-inflammatory compounds that are good for the heart.
Their findings were unveiled at the 247th National Meeting & Exposition of the American Chemical Society (ACS), the world’s largest scientific society. The meeting, attended by thousands of scientists, features more than 10,000 reports on new advances in science and other topics. It is being held at the Dallas Convention Center and area hotels through Thursday.
“We found that there are two kinds of microbes in the gut: the ‘good’ ones and the ‘bad’ ones,” explained Maria Moore, an undergraduate student and one of the study’s researchers.
“The good microbes, such as Bifidobacterium and lactic acid bacteria, feast on chocolate,” she said. “When you eat dark chocolate, they grow and ferment it, producing compounds that are anti-inflammatory.” The other bacteria in the gut are associated with inflammation and can cause gas, bloating, diarrhea and constipation. These include some Clostridia and some E. coli.
“When these compounds are absorbed by the body, they lessen the inflammation of cardiovascular tissue, reducing the long-term risk of stroke,” said John Finley, Ph.D., who led the work. He said that this study is the first to look at the effects of dark chocolate on the various types of bacteria in the stomach. The researchers are with Louisiana State University.
The team tested three cocoa powders using a model digestive tract, comprised of a series of modified test tubes, to simulate normal digestion. They then subjected the non-digestible materials to anaerobic fermentation using human fecal bacteria, according to Finley.
He explained that cocoa powder, an ingredient in chocolate, contains several polyphenolic, or antioxidant, compounds such as catechin and epicatechin, and a small amount of dietary fiber. Both components are poorly digested and absorbed, but when they reach the colon, the desirable microbes take over. “In our study we found that the fiber is fermented and the large polyphenolic polymers are metabolized to smaller molecules, which are more easily absorbed. These smaller polymers exhibit anti-inflammatory activity,” he said.
Finley also noted that combining the fiber in cocoa with prebiotics is likely to improve a person’s overall health and help convert polyphenolics in the stomach into anti-inflammatory compounds. “When you ingest prebiotics, the beneficial gut microbial population increases and outcompetes any undesirable microbes in the gut, like those that cause stomach problems,” he added. Prebiotics are carbohydrates found in foods like raw garlic and cooked whole wheat flour that humans can’t digest but that good bacteria like to eat. This food for your gut’s helpful inhabitants also comes in dietary supplements.
Finley said that people could experience even more health benefits when dark chocolate is combined with solid fruits like pomegranates and acai. Looking to the future, he said that the next step would be for industry to do just that.
Fried foods may interact with genes to influence body weight, say experts
Chances of obesity twice as likely for individuals at highest genetic risk
The results show that eating fried food more than four times a week had twice as big an effect on body mass index (BMI) for those with the highest genetic risk scores compared with lower scores. In other words, genetic makeup can inflate the effects of bad diet, says an accompanying editorial.
It is well known that both fried food consumption and genetic variants are associated with adiposity (fatness). However, the interaction between these two risk factors in relation to BMI and obesity has not been examined.
So a team of US researchers, led by Lu Qi, Assistant Professor at Harvard School of Public Health and Brigham and Women’s Hospital and Harvard Medical School, analysed interactions between fried food consumption and genetic risk associated with obesity in over 37,000 men and women taking part in three large US health trials.
They used food frequency questionnaires to assess fried food consumption (both at home and away from home) and a genetic risk score based on 32 known genetic variants associated with BMI and obesity.
Three categories of fried food consumption were identified: less than once a week, one to three times a week, and four or more times a week. Genetic risk scores ranged from 0 to 64 and those with a higher score had a higher BMI.
Height and body weight were assessed at the start of the trials, and weight was requested at each follow-up questionnaire. Lifestyle information, such as physical activity and smoking, was also collected.
The researchers found consistent interactions between fried food consumption and genetic risk scores on BMI.
Among participants in the highest third of the genetic risk score, the differences in BMI between individuals who consumed fried foods four or more times a week and those who consumed less than once a week were 1.0 kg/m2 in women and 0.7 kg/m2 in men.
For participants in the lowest third of the genetic risk score, the differences were 0.5 kg/m2 in women and 0.4 kg/m2 in men.
The authors stress that their results may have been affected by other unmeasured or unknown factors, despite carefully adjusting for several diet and lifestyle factors.
However, they say they indicate that the association between fried food consumption and adiposity may vary according to differences in genetic predisposition; and vice versa, the genetic influences on adiposity may be modified by fried food consumption.
Professor Lu Qi said: “Our findings emphasise the importance of reducing fried food consumption in the prevention of obesity, particularly in individuals genetically predisposed to adiposity.”
“This work provides formal proof of interaction between a combined genetic risk score and environment in obesity,” write Professor Alexandra Blakemore and Dr Jessica Buxton at Imperial College London in an editorial. However, the results “are unlikely to influence public health advice, since most of us should be eating fried food more sparingly anyway.”
In contrast, they stress that genetic information can be very valuable for treating ‘monogenic’ forms of obesity, caused by changes in a single gene. They say that it would therefore be “a great shame” to assume that genetics can be ignored in the management of obesity, and call for further studies “providing clinically useful predictions for individuals and enabling stratification of patients for appropriate care and treatment
March 17, 2014
Stimulants Used to Treat ADHD Influence BMI Growth Patterns Through Childhood With a BMI Rebound in Late Adolescence
ADHD Stimulant Treatment Initially Slowed BMI Growth Findings Are First to Link Childhood ADHD Treatment to Possible Later Obesity
A new study from researchers at Johns Hopkins Bloomberg School of Public Health found that children treated with stimulants for attention deficit hyperactivity disorder (ADHD) experienced slower body mass index (BMI) growth than their undiagnosed or untreated peers, followed by a rapid rebound of BMI that exceeded that of children with no history of ADHD or stimulant use and that could continue to obesity.
The study, thought to be the most comprehensive analysis of ADHD and stimulant use in children to date, found that the earlier the medication began, and the longer the medication was taken, the slower the BMI growth in earlier childhood but the more rapid the BMI rebound in late adolescence, typically after discontinuation of medication. Researchers concluded that stimulant use, and not a diagnosis of ADHD, was associated with higher BMI and obesity. The study was published in Pediatrics.
“Our findings should motivate greater attention to the possibility that longer-term stimulant use plays a role in the development of obesity in children,” said Brian S. Schwartz, MD, MS, Professor of Environmental Health Sciences, Epidemiology, and Medicine at the Bloomberg School of Public Health and lead author of the study. “Given the dramatic rise in ADHD diagnosis and stimulant treatment for it in recent decades, this is an interesting avenue of research regarding the childhood obesity epidemic, because the rises in each of these roughly parallel one another.”
Previous research has found substantial evidence that stimulant use to treat ADHD is associated with growth deficits, and some evidence of growth delays. However, the reported associations of ADHD with obesity in both childhood and adulthood was paradoxical and somewhat unexplained. The results of this study suggest it is likely due to the strong influence that stimulants have on BMI growth, with delays in early childhood and a strong rebound in late adolescence. The study also found longitudinal evidence that unmedicated ADHD is associated with higher BMIs, but these effects were small.
ADHD is one of the most common pediatric disorders, with a 9% prevalence among children in the U.S., and ADHD medication is the second most prescribed treatment among children. Over the past 30 years, treatment for ADHD with stimulants has increased rapidly. From 2007 to 2010, 4.2.% of children under age 18 had been prescribed stimulants in the past 30 days, more than five times the amount prescribed to the same-aged children between 1988 and 1984.
The study analyzed the electronic health records of 163,820 children, ages 3 to 18, in the Geisinger Health System, a Pennsylvania-based integrated health services organization. The research geographic area included 37 counties in central and northeastern Pennsylvania. There were an equal number of boys and girls. Nearly 7% — 11,080, or 6.8% — had an order for stimulants. (13,789, or 8.4%, received a diagnosis of ADHD. A total of 15,473 were prescribed stimulants, some for other reasons.) There were 201,854 orders for the ADHD medications used in the analysis. The median age at first stimulant use was 8.5 years. Median use was 183 days, with 50% of children taking stimulants for less than 6 months and 50% of children for more than 6 months.
The researchers compared the BMI trajectories of those who had never had a diagnosis or prescription (the “controls”) with three groups: 1.) those with a diagnosis but no stimulant prescription; 2.) those with orders for stimulants without an ADHD diagnosis and 3.) those with both an ADHD diagnosis and stimulant orders.
Those in group 3 had slower rates of BMI growth in early childhood, with more rapid rates during adolescence that eventually exceeded those of the controls. Those with a diagnosis of ADHD but no stimulant orders had more rapid BMI growth after age 10 versus the controls, but the effects were small.
“Stimulant use was strongly implicated,” said Dr. Schwartz. “The earlier stimulants were started and the longer they were used, the stronger was their influence on the degree of both the delayed BMI growth in early childhood and the rebound BMI growth in late adolescence. This is an important unintended consequence of stimulant use in childhood.”
New guidelines deem 13 million more Americans eligible for statins
DURHAM, N.C. – New guidelines for using statins to treat high cholesterol and prevent cardiovascular disease are projected to result in 12.8 million more U.S. adults taking the drugs, according to a research team led by Duke Medicine scientists.
The findings for the first time quantify the impact of the American Heart Association’s new guidelines, which were issued in November and generated both controversy and speculation about who should be given a prescription for statins.
In an analysis of health data published online March 19, 2014, in the New England Journal of Medicine, a team led by researchers at the Duke Clinical Research Institute found that most of the additional statin users under the new guidelines would be people older than age 60.
“We sought to do a principled, scientific study to try to answer how the new guidelines might affect statin use, particularly as they focused eligibility on patients with an increased risk of developing cardiovascular disease,” said lead author Michael J. Pencina, Ph.D., professor of biostatistics at DCRI. “By our estimate, there might be an uptake in usage as a result of the guidelines, from 43.2 million people to 56 million, which is nearly half of the U.S. population between the ages of 40 and 75.”
Pencina and colleagues from McGill University and Boston University used the National Health and Nutrition Examination Surveys (NHANES) for their analysis, focusing on 3,773 participants between the ages of 40-75 who had provided detailed medical information, including fasting cholesterol levels from blood tests.
The new guidelines expand the criteria for statin use to include people whose 10-year risk of developing cardiovascular disease, including stroke, is elevated based on a risk-assessment score.
The DCRI-led research team determined that the new guidelines could result in 49 percent of U.S. adults ages 40-75 being recommended for statin therapy, an increase from 38 percent.
The increase is much more pronounced among adults free of cardiovascular disease who are over age 60, with 77 percent recommended for statin use under the new guidelines vs. 48 percent under the previous standards. This contrasts with a modest increase from 27 percent to 30 percent among U.S. adults between the ages of 40 and 60.
Those most affected by the new recommendations are older men who are not on statins and do not have cardiovascular disease. Under the earlier guidelines, about 30.4 percent of this group of men between the ages of 60-75 were recommended for statin use. With the new guidelines, 87.4 percent of these men would be candidates for the therapy. Similarly for healthy women in this age group, those recommended for preventive statin use are projected to rise from 21.2 percent to 53.6 percent.
“The biggest surprise of the research was the age-dependent split for those affected by the new guidelines,” Pencina said. “We anticipated that the impact would be age-dependent, but not to the degree observed. The changes for both men and women in the older age groups where huge compared to those between the ages of 40 and 60.”
Overall, of the 12.8 million additional U.S. adults recommended for statin use under the new guidelines, 10.4 million are people who would be prescribed the drugs for preventive care. Of those preventive users, 8.3 million would be people over the age of 60.
The analysis also projects that an estimated 1.6 million adults previously eligible for statins under the old guidelines would no longer be candidates under the new standards. This group included primarily younger adults with elevated cholesterol but low 10-year risk of cardiovascular disease.
Pencina said an important limitation of the study is the necessary assumption that the new guidelines would be followed to the letter; in real life, people may be recommended for statins but decline to start the therapy.
“Recommendations are just that – recommendations,” Pencina said. “These guidelines correctly call for a thorough discussion between the doctor and patient about the risks and benefits of statins. It’s not like everybody who meets the guidelines should all of a sudden go on statins.”
Studies of gut flora in infants and toddlers could lead to better health
Breastfeeding until at least nine months of age increases prevalence in the gastrointestinal tract of Lactobacilli and Bifidobacteria, species which are known to contribute to development of a healthy immune system, according to a paper describing the establishment of the intestinal microbiota during the first three years of life. The research was published ahead of print in the journal Applied and Environmental Microbiology.
In the study, the investigators sampled the gut microbiota in the feces of 300 children at 9, 18, and 36 months of age. The nutritional factor with the greatest impact on the composition of the gut flora was the time of cessation of breast feeding.
“This is to our knowledge the first study to characterize the gut microbiota in such a large cohort of children for this duration,” says corresponding author Tine Rask Licht, of the Technical University of Denmark.
The investigators also examined the microbiota, seeking enterotypes, or characteristic microbial communities. While enterotypes tend to be stable in adults (absent antibiotic use or major changes in diet) the investigators found that one particular enterotype-like grouping was prevalent at 18 months and another at 36 months, but that children frequently flipped a few times between the two.
“This indicates that the microbiota is still not completely stably established until after this time,” says Licht.
“The research could ultimately lead to supplementation of infant formulas—or food for adults—with specific bacteria or carbohydrates expected to promote a healthy gut microbiota,” says Licht. She and her collaborators are currently involved in studies testing effects of such pro- and prebiotics in animal models as well as in humans, she says, noting that in Denmark, several multinational companies are also involved in this research.