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Health and Fitness, Microbiology, Nutrition, Public Health, Research, Stanford News

Can low-fiber diets’ damage to our gut-microbial ecosystems get passed down over generations?

Can low-fiber diets' damage to our gut-microbial ecosystems get passed down over generations?

fast food decisionsUh-oh.

A study conducted in mice raises suspicions that we humans may be halfway down the road to the permanent loss of friendly gut-dwelling bacteria who’ve been our constant companions for hundreds of millennia. That’s probably not good.

Virtually all health experts agree that low-fiber diets are sub-optimal. One big reason: Fiber, which can’t be digested by human enzymes, is the main food source for the friendly bacteria that colonize our colons. Thousands of distinct bacterial species thrive within every healthy mammal’s large intestine. Far from being victimized by these colonic cohabitants, we’d be hard put to live without them. They fend off pathogens, train our immune systems, help us digest food we’d otherwise be unable to use and even guide the development of our tissues.

From a news release I wrote about the new study, which was spearheaded by Stanford microbiology/nutrition explorers  (and husband/wife team) Justin Sonnenburg, PhD, and Erica Sonnenburg, PhD, and published in Nature:

[Previous] surveys of humans’ gut-dwelling microbes have shown that the diversity of bacterial species inhabiting the intestines of individual members of hunter-gatherer and rural agrarian populations greatly exceeds that of individuals living in modern industrialized societies. … In fact, these studies indicate the complete absence, throughout industrialized populations, of numerous bacterial species that are shared among many of the hunter-gatherer and rural agrarian populations surveyed, despite those groups’ being dispersed across vast geographic expanses ranging from Africa to South America to Papua New Guinea.

Another piece of information: The proliferation of nearly fiber-free, processed convenience foods since the mid-20th century has resulted in average-per-capita fiber consumption in industrialized societies of about 15 grams per day. That’s as little as one-tenth of the intake among the world’s dwindling hunter-gatherer and rural agrarian populations, whose living conditions and dietary intake presumably most closely resemble those of our common human ancestors.

Perhaps the most significant sources of our intestinal bacterial populations is our immediate family, especially our mothers during childbirth and infancy. So, if our low-fiber diets are depleting our intestinal ecosystems, could that depletion get passed down from one generation to the next?

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Bioengineering, Immunology, Public Health, Research

Working towards a lifelong, universal flu vaccine

Working towards a lifelong, universal flu vaccine

4919795171_771ae41b50_b_flickr_BlakePatterson_300x247To prepare for holiday socializing, I always roll up my sleeve to get an annual flu shot. I would much rather share food and gifts than a virus with my friends and family. And I don’t want to spend my precious vacation time sick.

However, seasonal flu vaccines are not always effective. There are thousands of strains of influenza virus and each can mutate over the course of the flu season. Seasonal vaccines only protect against a few of the most likely strains. As a result, flu-associated deaths range from 3,000 to 49,000 Americans per flu season, according to the U.S. Centers for Disease Control and Prevention.

Scientists have long sought a lifelong vaccine that would be effective against any variety of influenza, and they are now making significant progress towards this goal.

I recently spoke with Ian Wilson, PhD, a leading structural and computational biologist at the Scripps Research Institute, about his team’s universal flu vaccine research. He told me:

Our research has identified a good target for such a vaccine on a protein called hemagglutinin (HA) that is present on the surface of all influenza viruses. The HA protein has two major components: the head portion, which mutates and varies from strain to strain, and the stem, which is similar across most flu strains. We know that the HA stem is the virus’s most vulnerable spot, and provokes the greatest breadth of immune response. So a synthetic version of the stem was designed, called a mini-HA that mimicked the HA stem.

A key part of Wilson’s flu research took place at the Stanford Synchrotron Radiation Lightsource at SLAC National Accelerator Laboratory, where the scientists used a technique called x-ray crystallography to look at the atomic structure of the mini-HA at each stage of its development. I wrote a recent news article about their efforts.

Though this is important research, more work needs to be done. “We still need to perform human trials and also want to develop a vaccine that protects against all types of influenza that cause human pandemics,” Wilson said.

Jennifer Huber, PhD, is a science writer with extensive technical communications experience as an academic research scientist, freelance science journalist, and writing instructor.

Previously: Working to create a universal flu vaccineScience Friday-style podcast explains work toward a universal flu vaccine and Experts and 8-year-olds agree: It’s worth getting a flu shot
Photo by Blake Patterson

Global Health, Public Health, Research, Stanford News

A moment in the sun for the tsetse fly – and the Stanford researcher studying its effect on Africa

A moment in the sun for the tsetse fly - and the Stanford researcher studying its effect on Africa

tsetse flyThanks to a study published earlier this year, the tsetse fly has garnered attention from The Economist, The Guardian, Humanosphere, and – most recently – from the Department of Medicine’s Annual Report.

What makes this flying pest so important? In the American Economic Review paper, Stanford’s Marcella Alsan, MD, PhD, showed that by spreading sleeping sickness the tsetse fly may have significantly affected Africa’s economic development.

In precolonial Africa, sleeping sickness killed livestock en masse in areas where the fly was prevalent. Alsan, a Stanford Health Policy core faculty member whose work focuses on the relationship between health and socioeconomic disparities, asserts that where cows and other livestock were not available in large numbers, farmers did not develop progressive agricultural methods. This produced lower crop yields and limited mobility for people and goods.

“Communicable disease has often been explored as a cause of Africa’s underdevelopment,” Alsan says in this Department of Medicine piece. “Although the literature has investigated the role of human pathogens on economic performance, it is largely silent on the impact of veterinary disease.”

Because fewer domesticated animals limited their transportation options and because sleeping sickness among humans thinned population densities, people living in tsetse-heavy areas of Africa were less likely to develop a centralized political system, making economic development more difficult. The lack of centralization continues to affect the continent today.

“The evidence suggests current economic performance is affected by the tsetse through the channel of precolonial political centralization,” Alsan wrote in the American Economic Review piece.

This work may help to determine why many African communities lack the development of wealthier countries. “It’s incredibly important to shine light on issues that are Africa-specific and therefore may not garner as much attention as those economic and medical issues that affect wealthier regions of the world,” Alsan noted.

Nicole Feldman is the communications associate at Stanford Health Policy.
Photo by David Dennis

Cancer, Pain, Palliative Care, Patient Care, Public Health, Stanford News

Ernest and Isadora Rosenbaum Library: A free, comprehensive guide to living with cancer

Ernest and Isadora Rosenbaum Library: A free, comprehensive guide to living with cancer

Spiegel in office - 600“What’s it like to be told you have cancer?” I asked a friend recently. She told me she was shocked to have received the news, and that this shock quickly gave way to a seemingly endless string of questions. How did I get cancer? What’s the best treatment? What will my care be like? What will the rest of my life be like?

As we talked, I learned that getting her the best care possible, although important, wasn’t the only thing she needed to survive. An equally important need was the peace of mind she regained when her doctors, caregivers and loved-ones helped her tackle her unanswered questions.

Addressing the questions and needs of cancer patients, like my friend, is the primary aim of the web-based Ernest and Isadora Rosenbaum Library at Stanford’s Center for Integrative Medicine.

Recently, I had the opportunity to talk about the library with the center’s medical director, psychiatrist David Spiegel, MD. Spiegel first came to know the late Ernest Rosenbaum, MD, through Rosenbaum’s work at San Francisco’s Mt. Zion Hospital. Rosenbaum treated cancer by addressing the patient as a whole – considering not just patients’ physical needs, but their emotional ones as well – and, at the time, his approach was groundbreaking. He wrote Everyone’s Guide to Supportive Cancer Care, Everyone’s Guide to Cancer Therapy and The Inner Fire decades before such support was recommended by the Institute of Medicine in its report, Lost in Transition, long before the National Cancer Institute had an Office of Cancer Survivorship, and before palliative care was widely talked about.

When Spiegel opened the Stanford Center for Integrative Medicine in 1998, Rosenbaum brought his cancer supportive care program to Stanford. There, Rosenbaum and colleagues gave and recorded talks and penned articles that address the many scientific and emotional aspects of cancer care.

Ernie and IzzyRosenbaum bequeathed his writings to Stanford when he passed away in 2010. Volunteer Vahe Katros did the hard work of bringing this material to the web, donating hundreds of hours to bring the website to life. “Vahe represents the best in those who volunteer to help cancer patients, and he shows how we can all help one another,” Spiegel said.

Visitors to the online library will find information on such things as coping with cancer, sources of support, the value of forgiveness and the role of creativity – “topics [that] Rosenbaum selected due to his being personally being involved in the struggles of thousands,” Spiegel explained. The library contains excerpts from Rosenbaum’s book, The Inner Fire, and will be expanded in 2016 to include writings from his unpublished final work and additional content.

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Health and Fitness, Patient Care, Public Health

Doctor’s visits should include exercise check, researchers urge

Doctor's visits should include exercise check, researchers urge

21189950643_4982e7769a_zEvidence on the health benefits of exercise abounds. Despite that, exercise is discussed in fewer than 40 percent of doctors’ exams in the United States, and that needs to change, a team of researchers including Stanford’s Kathy Berra, MSN, NP-BC, wrote last week in a piece in the Journal of the American Medical Association. Berra is affiliated with the Stanford Prevention Research Center.

“The lack of physical activity counseling in clinical settings represents a lost opportunity to improve the health and well-being of patients, and with minimal cost,” the team wrote.

It can be as easy as having a medical assistant ask a patient if he or she exercises while measuring blood pressure, temperature and weight, Berra told me. Physicians or nurses can then follow up and offer congratulations for a job well done or offer suggestions to incorporate or improve exercise regimes, she said.

“It shows the patient you are really interested in them doing well, interested as much in activity as in giving them another pill,” she said.

Asking the patients to keep and exercise record can also be very effective, the researchers write. Health-care providers should then ask to see it on subsequent visits. “There’s a lot of competition for time during office visits, but it doesn’t have to take a long time,” Berra said.

The key is keeping the tone motivational and expressing genuine interest, she said. Clinicians can also offer a list of helpful apps or refer patients to a community gym or exercise program, they researchers wrote.

Berra said she added her voice to a nationwide chorus calling for health-care providers to get more involved in exercise advocacy.

Previously: Examining the long-term health benefits for women of exercise in adolescence, Study clarifies link between dieting, exercise and reduced inflammation
Photo by Dragan

Infectious Disease, Patient Care, Pediatrics, Public Health

Should doctors give up their white coats?

Should doctors give up their white coats?

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When you google ‘doctor,’ virtually every image shows a person in a long-sleeved white coat. The crisp white coat with a stethoscope around the neck has long symbolized the profession. However, there is controversy about whether doctors should give up their classic uniform, as described in a recent story in the Boston Globe.

Britain’s National Health Service banned white coats several years ago, requiring doctors to be bare below the elbows to avoid spreading infections. Many clinical departments in the United States have done the same. The argument goes something like this:

  • The sleeves of white coats are germ magnets.
  • Doctors don’t launder their white coats very often, so deadly infections can be spread from one patient to another.
  • Therefore, doctors shouldn’t wear long-sleeved white coats.

As a pediatric infectious disease specialist at Stanford, Charles Prober, MD, supports this theory. He told me during a recent interview: “In terms of the infectious disease risk, there is little question that one can carry bacteria or viruses on your clothing — whether it’s a white coat or the sleeve of your shirt, and one way to lessen that is to wash up to the elbows, especially when you’re going into high-risk environments like the ICU or nursery. Obviously you can only wash up to your elbows if they aren’t covered with something.

William Benitz, MD, division chief of neonatal and developmental medicine, agrees:

I find the summary reports highly credible and accept the contention that the long sleeves of white coats harbor infectious agents and carry them from patient to patient. We banned white coats in our NICU about 5 years ago, along with a mandate for baring arms to the elbow and hand cleansing upon entering any patient room. Part of the reason for the former is to reinforce and provide active visual evidence of the latter. We used to hear ‘but I won’t touch anything’ a lot, but that was often not so. Not an issue now.

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Education, Nutrition, Public Health, Research, Stanford News, Videos

Online Stanford nutrition course improves participants’ eating habits, study finds

Online Stanford nutrition course improves participants' eating habits, study finds

I’m a big fan of Stanford’s free online course on child nutrition and cooking. And it’s not just me: Since the course launched in early 2014, more than 200,000 people have enrolled and watched the quick, informative, charming videos about understanding nutrition and making healthy food for kids. My favorite video, above, shows how to cook toad-in-a-hole, a comfort food I’ve loved since my own childhood.

Recently, instructor Maya Adam, MD, and her colleagues tested the effect of completing the course. When they designed the course, they hoped it would improve participants’ eating habits. A few other institutions had seen promising results from smaller online nutrition courses, but none of those combined nutrition instruction with hands-on demos of how to actually put their advice into practice in the kitchen. Yet other research suggests that making this connection between the “why” and “how” of healthy eating is important, since many people say that their lack of cooking know-how keeps them from eating well.

The results of the study, which appears in the International Journal of Behavioral Nutrition and Physical Activity, showed that the course is a success. Based on data from 7,422 participants surveyed about their eating habits before and after taking the course, the material presented helped participants cook fresh foods at home more often and eat more fresh fruits and vegetables. After the course, participants were also more likely to say that their previous day’s dinner was enjoyable and healthy.

“This is part of a growing body of research suggesting that just learning to cook can lead to improved dietary intake, which has amazing implications for public health interventions aimed at preventing overweight and obesity,” Adam told me in an e-mail.

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Health Policy, Infectious Disease, Microbiology, Public Health, Research, Stanford News

Excessive antibiotic use in flu season contributes to resistance

Excessive antibiotic use in flu season contributes to resistance

addiction-71573_1280The cold and flu season is upon us — and with that comes the potential overuse of antibiotics. All too often, physicians prescribe antibiotics for viral infections, which typically is ineffectual and can even be dangerous for elderly Medicare patients.

An estimated 2 million Americans are infected with drug-resistant organisms each year, resulting in 23,000 deaths and more than $20 billion in excess costs, according to the Centers for Disease Control and Prevention.

Excessive antibiotic use in cold and flu season is not only costly, but it also contributes to antibiotic resistance, writes Marcella Alsan, MD, PhD, and her co-authors in a study published in the December edition of Medical Care. The study’s objective was to develop an index of excessive antibiotic use in cold and flu season and determine its correlation with other indicators of clinically appropriate or inappropriate prescribing.

Alsan, a core faculty member at Stanford Health Policy, and senior author, Dartmouth economist Jonathan Skinner, PhD, concluded that flu-related antibiotic use was correlated with prescribing high-risk medications to the elderly.

“These findings suggest that excessive antibiotic use reflects low-quality prescribing,” the authors wrote. “They imply that practice and policy solutions should go beyond narrow, antibiotic specific, approaches to encourage evidence-based prescribing for the elderly Medicare population.”

To better understand patterns of antibiotic overuse and whether such patterns reflect prescribing quality, the authors developed a measure that isolates antibiotic prescribing in response to state-by-state influenza activity. They focused on the elderly, as national data on antibiotic use are readily available and because the interactions between multiple prescriptions are particularly important for this population.

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Global Health, Infectious Disease, Public Health, Public Safety

Stanford team develops a method to prevent the viral infection that causes dengue fever

Stanford team develops a method to prevent the viral infection that causes dengue fever

327708441_433edf50d4_zDengue fever is the most widespread and fastest growing mosquito-borne virus in the world. It infects an estimated 390 million people each year — nearly twice the number of people infected annually by malaria — and unlike malaria, there is no vaccine or treatment.

Despite the severity and worldwide frequency of the disease, dengue fever receives relatively little press in the United States. But soon this trend may change. Just recently an outbreak of dengue fever struck Hawaii’s Big Island and the reach of this tropical disease is expected to spread.

Now, a team of Stanford researchers led by Judith Frydman, PhD, have developed a new way to target the disease by using a drug compound that tinkers with a critical cellular pathway in the host, blocking the virus at multiple steps. Frydman is a professor of biology and of genetics.

A Stanford News story explains:

Frydman’s group focused on Hsp70, a type of protein found in most organisms and known as a “chaperone.” Hsp70’s main job is to help other proteins fold into their functional shape, and to then protect them from damage by environmental stresses. DENV (dengue fever), like many other viruses, also relies on Hsp70, to help replicate the viral genome, and ultimately produce the viral proteins it needs to take control of the host cells and spread infection.

Frydman’s team discovered that using a specific compound to inhibit Hsp70 in human blood cells blocks the virus without harming the cells. This compound is effective against different strains and types of dengue fever and it blocks other insect-borne diseases, including West Nile virus, yellow fever and tick-borne encephalitis.

“Our findings have major implications for our understanding of the interface between viral and chaperone biology, and provide a new way of thinking about strategies to develop a novel class of antivirals,” Frydman said.

Previously: Exploiting insect microbiomes to curb malaria and dengueFighting fire with fire? Using bacteria to inhibit the spread of dengue and Dengue fever in New Caledonia
Photo by Andy Simonds

In the News, Pain, Public Health

Pain: When the professional becomes personal

Pain: When the professional becomes personal

3199296759_e5130dc6c1_zFor 10 long months, Philip Pizzo, MD, suffered from incapacitating nerve pain. Even worse, top medical experts were stumped. He describes his ordeal in a recent essay in STAT News:

I tried everything — medication, physical therapy, deep-tissue massage, acupuncture — but nothing worked. Magnetic resonance imaging of my spine, hip, and pelvis didn’t show anything suspicious.

As a physician, a former dean of the School of Medicine, and chair of an Institute of Medicine panel on pain, Pizzo had known intellectually about the problem of chronic pain. Now he had experienced its unremitting intensity firsthand.

His pain was relieved by an unusual diagnosis and surgery, but Pizzo knows many others aren’t as fortunate.

“Nearly 100 million Americans suffer from chronic pain. We need to do more for them,” he writes.

Previously: Laughing through the pain: A comedy writer’s experience with chronic illness, “People are looking for better answers”: A conversation about chronic pain and  Study: Effects of chronic pain on relationships can lead to emotional distress
Photo by Kevin Dooley

 

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