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norexia nervosa is a serious eating disorder, affecting over 3 million Americans. New research published in Psychosomatic Medicine suggests that people with this debilitating disease may have very different gut microbial communities than those found in healthy individuals.
Moreover, researchers at the University of North Carolina (UNC) School of Medicine speculate that this bacterial imbalance could be linked to some of the psychological symptoms related to the disorder, which has the highest mortality rate of any mental health issue.
The research, led by Ian Carroll, PhD, senior author of the paper and assistant professor of medicine in the UNC Center for Gastrointestinal Biology and Disease, suggests that gut bacteria, the trillions of bacteria that affect digestive health and immunity, could play a prominent role in the symptoms of anorexia nervosa.
It is known that microbial diversity is a sign of better overall health. Previous studies have also suggested that the abundance and diversity of gut microbiota could also affect the so-called "gut-brain axis."
In previous research, scientists took gut microbial communities from an obese person and put them into germ-free mice, which are maintained in sterile conditions and lack intestinal microbiota. The result was a greater weight gain in mice with these bacteria than in germ-free mice that had been colonized with gut microbiota from a lean person. This suggests that gut microbes could mediate weight gain or loss.
In other experiments where gut bacteria were added to germ-free mice, altered behavior resulted, especially in relation to anxiety and stress.
Less diverse microbial communities in those with very low weight
The UNC team wanted to study this relationship further to find out if altering gut microbiota could help patients with anorexia nervosa to maintain weight and stabilize mood over time.
They collected fecal samples from 16 women with anorexia nervosa after they were first admitted into the UNC Center of Excellence for Eating Disorders, and then again on discharge from the center after their weight was restored. The samples were analyzed for composition and diversity of gut microbiota.
They also collected gut microbiota from 12 healthy individuals for comparison.
Susan Kleiman, a graduate student in Carroll's lab and first author of the paper, found significant changes in the gut bacteria populations between admission and discharge.
The samples taken at admission had fewer different types of bacteria, making the intestinal communities much less diverse. On discharge, the microbial diversity had increased but was still significantly less diverse than that of the healthy individuals.
As the microbial communities in patients with anorexia improved during clinical care and weight gain, the moods of patients also improved, suggesting a link between the two.
Learn more about anorexia nervosa
The next question is whether improving microbial abundance and diversity could help relieve symptoms related to the eating disorder.
To help them find out, Carroll and a team of researchers have received a 5-year, $2.5-million grant from the National Institutes of Mental Health (NIMH) to further study the relationship between gut microbiota and anorexia nervosa.
The team will characterize the microbiotas of a large number of people with anorexia nervosa as they enter UNC's clinic and when they are discharged, normally when they reach about 85% of their ideal body weight.
Then they will put those gut bacteria in germ-free mice, to investigate how the microbiota from anorexia nervosa patients affects the biology and behavior of the mice.
If the bacteria have a detrimental effect on the mice, it is possible that cultivating a healthy microbiota could be used in therapy for people with anorexia nervosa.
Carroll says:
"We're not able to say a gut bacterial imbalance causes the symptoms of anorexia nervosa, including associated symptoms, such as anxiety and depression. But the severe limitation of nutritional intake at the center of anorexia nervosa could change the composition of the gut microbial community.
These changes could contribute to the anxiety, depression, and further weight loss of people with the disorder. It's a vicious cycle, and we want to see if we can help patients avoid or reverse that phenomenon."
Treatments for anorexia nervosa need improvement. The process of weight gain and renourishment can be extremely uncomfortable, so that after leaving the hospital, patients often begin to lose weight again and face readmission.
If specific alterations in the microbiota can help decrease the discomfort of renourishment, enable better weight regulation and positively affect behavior, this could lead to better outcomes for patients.
Carroll points out that this will not be "the magic bullet for people with anorexia nervosa," because other important factors are involved. But he believes that if the gut microbiota is associated with a variety of health and brain-related issues, it could make a difference for people with anorexia nervosa.
While anorexia nervosa mostly starts during adolescence, a Spotlight from Medical News Today has previously investigated how eating disorders can affect people of any age.
offee and diabetes are two of the most commonly covered topics in current medical news. The latest research looks in detail at some of coffee's ingredients and their potential effects on diabetes.
The prevalence of coffee and diabetes in modern media makes a great deal of sense: almost 1 in 10 Americans are diabetic, and more than half of American adults drink coffee daily.
The US spends roughly $40 billion on coffee per year, and in 2012, the total estimated cost of diagnosed diabetes in America was $245 billion.
Any links between these two unlikely bedfellows are likely to be chased down with vigor.
Recent research published in the American Chemical Society's Journal of Natural Products gives us a glimpse into the potential benefits of some of coffee's natural compounds in the management of type 2 diabetes.
Type 2 diabetes
Individuals with type 2 diabetes have a resistance to insulin. Insulin normally helps control the amount of glucose in the blood. If levels are high, it instructs the liver and muscles to absorb more.
Diabetes causes the body to stop reacting to insulin as it should. Insulin is released, but the liver and muscle cells no longer absorb the excess glucose. In the early phases of the disease, an increased amount of insulin is produced in an effort to convince the body to take on more glucose.
As the disease progresses, insulin-producing cells in the pancreas slowly die off through overuse.
The health implications of diabetes can be dire: damage to large blood vessels in the heart, brain and legs. Also, damage to smaller blood vessels can cause problems in the kidneys, eyes, feet and nerves.
The chemistry of coffee
All in all, there are more than 1,000 distinct chemical compounds in coffee. This impressive recipe includes quinic acid, 3,5-dicaffeoylquinic acid, acetylmethylcarbinol, dimethyl disulfide, putrescine, niacin, trigonelline, theophylline and our old friend and foe, caffeine.
Each of coffee's ingredients has the potential to affect human biology. More than likely, the majority of compounds, in the tiny amounts they are present in coffee, will not have a great effect on the body.
Having said that, there is no reason not to study each of these molecules in an effort to get to grips with the myriad of effects that coffee appears to exert on us.
Coffee and diabetes
Research into coffee and its ability to prevent or slow the onset of type 2 diabetes has garnered a fair amount of attention. A recent review of the literature concluded that habitual coffee drinking does seem to lower the risk of type 2 diabetes.
The next challenge is to tease apart the many components of coffee to pinpoint the active ingredients. As the bewildering list of chemicals above infers, this may be a gargantuan task.
Recent research conducted by Søren Gregersen and colleagues at the Department of Endocrinology and Internal Medicine at Aarhus University Hospital in Denmark may have narrowed the search.
Gregersen and his team looked at the effect of a number of coffee's constituents on rat cells in vitro. Most of the compounds did not have significant effects, but cafestol and caffeic acid threw out some intriguing results.
When surgeon Alan Bauman started his hair restoration practice in Boca Raton, Fla., in the late 1990s, about 10% of his patients were women. Now, he says, half are. Joseph Greco, a hair loss specialist in Sarasota, Fla., says his share of female patients has gone from 25% to 60% in the last decade alone.
There's no reason to think more women these days are losing hair. Almost all women lose some hair as they age and some women – just like some men – are genetically predisposed to lose a lot. Women rarely go bald, but what starts with a widening part, noticeable shedding or a shrinking pony tail can become significant, scalp-exposing hair thinning for about one third of women, studies show.
How women feel about that may be changing, says Melissa Piliang, a dermatologist specializing in hair loss at the Cleveland Clinic.
"I think there is an increased awareness and an increased interest in treatment," Piliang says. "For our grandmothers' generation, women over 50 were considered old. Now women that age are considered pretty young. Many also have jobs in which appearance is important."
And, it's fair to say, many also are seeing marketing for an increasing array of hair restoration products and procedures aimed at women – including a pricey but unproven treatment that both Bauman and Greco specialize in. It involves scalp injections with something called platelet-rich plasma (PRP).
Bauman, Greco and other practitioners – some of whom market PRP as a "vampire hair treatment," akin to the bloody "vampire facials" made famous by Kim Kardashian – say that substances in concentrated plasma, taken from a patient's own blood, can stimulate hair regrowth. They say the procedure is safe and produces noticeable results in most, but not all, male and female patients. A 20% to 25% increase in hair mass is typical, Bauman says.
But studies so far have been small and most have lacked the comparison groups that would show how PRP stacks up against other treatments or no treatment at all. "The early findings show promise, but more studies are needed to know whether this is a safe and effective treatment," the American Academy of Dermatology says.
Also, a lack of standardization – with each clinic using its own methods – "means it's buyer beware out there," Bauman says.
Those buyers are spending big bucks: Bauman charges $2,500 for a PRP treatment that he says needs to be repeated once a year on average. Greco says he repeats his version three times over the first 18 months for typical "female pattern hair loss" patients, charging $1,600 for the first treatment, $1,400 for the second and $1,000 for the third. Patients have an incentive to return because any new hair will fall out when treatment stops – just as it does with any treatment except for hair transplants.
But no one considers PRP the first-line treatment for women with hair loss.
That distinction goes to minoxidil, a liquid or foam applied to the scalp, available over the counter for years. The Food and Drug Administration approved a full-strength foam (a 5% solution) for women in 2014 and it is now sold as Women's Rogaine. The big advantage over older 2% versions is that it can be used once a day, instead of twice. It costs about $35 for a four-month supply.
Pililang says about 80% of women using minoxidil will stop losing hair and about half will regrow some. "It's not going to take someone who's 50 or 60 back to the hair they had at 20," she says.
"It doesn't work for everybody, but I tell my patients to use it diligently for six months and then look in the mirror and see how they feel," says Paradi Mirmirani, a dermatologist specializing in hair loss at Kaiser Permanente in Vallejo, Calif. Because hair loss caused by aging and genes gets worse over time, even maintaining hair "is a win," she says. "But patients have to decide whether it's worth the time and money."
The main side effects associated with minoxidil are scalp irritation and itching. And some women report unwanted facial hair growth – something that package instructions say might be prevented with careful application.
Another treatment that might work for some women: laser therapy with comb devices that sell for about $200 to $500 or caps that cost even more. These are FDA-approved for safety and recent studies suggest "a modest benefit," Mirmirani says.
Some women are candidates for hair transplant. But because women tend to lose hair all over their heads, not in the distinct bald spots common in men, finding lusher sections that can be moved to cover sparser areas is "more challenging," Piliang says.
Supplements such as biotin, marketed for hair health, are unproven, Piliang and Mirmirani say. But eating a healthy diet, protecting hair from the sun and not smoking can help, they say.
Also important to know: not all women's hair loss is the result of aging and genes. And some causes are treatable or temporary. Among them:
• Pregnancy. Many women see temporary hair loss after pregnancy.
• Stress. Hair also can shed after stressful or traumatic events.
• Iron deficiency, thyroid, hormone and immune disorders. Treating them can often stop any associated hair loss.
• Medications. Cancer drugs but also drugs used to treat acne, depression, blood clotting and other conditions can cause hair loss.
Authors of a small study conclude that "vitamin C supplementation represents an effective lifestyle strategy" for reducing the blood vessel constriction that is increased in overweight and obese adults.
The study of 35 obese or overweight adults compared the effects of vitamin C and exercise on the protein known as endothelin-1, which has a constricting action on small blood vessels.
The protein's activity is raised in overweight and obese people and because of this high endothelin-1 activity, small vessels are more prone to constricting, becoming less responsive to blood flow demand and increasing the risk of vascular disease.
The study's abstract is being presented at the American Physiological Society's 14th International Conference on Endothelin, taking place in Savannah, GA.
The researchers explain that exercise has been shown to reduce endothelin-1 activity, but including it in a daily routine can be challenging.
Daily dose as helpful as walking
Caitlin Dow, PhD, postdoctoral research fellow at the University of Colorado, Boulder, led the study to examine whether vitamin C supplements, which have been reported to improve vessel function, can also lower endothelin-1 activity.
The researchers found that daily supplementation of vitamin C at a time-release dose of 500 mg daily reduced endothelin-1-mediated vessel constriction as much as walking did.
The 35 sedentary, overweight/obese adults completed 3 months of either the supplementation (20 participants) or aerobic exercise training (15 participants).
Measures included forearm blood flow and responses to intra-arterial infusion of endothelin-1 before and after each intervention.
Vasoconstriction to endothelin-1 increased similarly - about two-fold - in response to both interventions.
Turning to the other end of the spectrum of physical fitness, a review in February 2013 found that vitamin C may help people under heavy physical stress, such as marathon runners, cut their chances of getting a cold.
In June 2013, it was reported that vitamin C consumption can cut the risk of people with asthma developing exercise-induced bronchoconstriction.
Researchers call the increase in morbidity and mortality due to prescription opioid abuse an "epidemic."
In 2013, the 16,200 deaths resulting from prescription opioid disorders exceeded the 14,774 deaths from use of all illicit drugs combined.
The team, led by Dr. Beth Han, PhD, of the Substance Abuse and Mental Health Services Administration in Rockville, MD, set out to assess national trends in and characteristics of nonmedical prescription opioid use and use disorders, and the national trend in related mortality.
To investigate prevalence and related risk factors, they looked at data from 472,200 participants in the 2003-2013 National Surveys on Drug Use and Health (NSDUH).
Nonmedical use of prescription opioids was defined as "use without a prescription or [...] with a prescription, simply for the experience or feeling caused by opioids."
Increase in disorders seen
Disorders were classed as dependence on or abuse of: alcohol, marijuana, cocaine, hallucinogens, heroin, inhalants, or nonmedical use of prescription pain relievers, sedatives or stimulants.
The researchers found increased trends in dependence, morbidity and mortality rates:
From 2003-2013, prescription opioid dependence rose from 0.4% to 0.6% in people aged over 12
Associated Emergency Department visits rose from 82.5 to 184.1 per 100,000 from 2004-2011
Prescription opioid related-deaths rose from 1.4 to 5.1 per 100,000 from 1999-2013
Drug overdose death rates involving prescription opioids increased from 4.5 per 100,000 in 2003 to 7.8 per 100,000 in 2013.
Medications were bought, stolen or given by friends or relatives, prescribed by physicians, or bought from drug dealers or strangers.
Who is affected?
Disorders were more common among non-Hispanic white users, although the most frequent users of prescription opioids were non-Hispanic black people.
Disorders were more common among people without a high school diploma, those who were disabled for work, people with major depressive episodes, those without health insurance and those with Medicaid coverage rather than private health insurance.
People with dependences on alcohol, marijuana, cocaine, hallucinogens, heroin, stimulants, sedatives and nicotine were also more prone to disorders - as were those who stole or bought drugs, compared with those who received them for free from friends or relatives.
A public health concern
The epidemic in increased high-intensity prescription opioid use represents a major public health concern.
Previous studies have shown a strong relationship between inappropriate opioid prescribing and negative health outcomes; the current trend has occurred at a time when the quantities of opioids prescribed has increased.
From 1999-2002, 57.6% of opioid users took an opioid stronger than morphine or morphine-equivalent; by 2011-12, this figure had increased to 80%.
Use of higher amounts of prescription opioids is a significant risk factor for overdose death.
The team recommends identifying at-risk users to prevent them from developing disorders. They also suggest identifying patterns of inappropriate receipt of prescription opioids. Patients with opioid-related disorders and associated substance use disorders - plus nicotine dependence and depression - should be screened for treatment.