Western high-fat diet can cause chronic pain,

 A typical Western high-fat diet can increase the risk of painful disorders common in people with conditions such as diabetes or obesity, according to a groundbreaking paper authored by a team led by The University of Texas Health Science Center at San Antonio, also referred to as UT Health San Antonio.

Moreover, changes in diet may significantly reduce or even reverse pain from conditions causing either inflammatory pain - such as arthritis, trauma or surgery - or neuropathic pain, such as diabetes. The novel finding could help treat chronic-pain patients by simply altering diet or developing drugs that block release of certain fatty acids in the body.

The paper, more than five years in the making, was published in the June edition of the journal Nature Metabolism by a collaborative team of 15 local researchers, headed by first co-authors Jacob T. Boyd, MD, PhD, and Peter M. LoCoco, PhD, of the Department of Endodontics at UT Health San Antonio.

In all, 11 of the co-authors are from UT Health San Antonio, including seven current or former students of its Graduate School of Biomedical Sciences; three represent the Department of Chemistry at the University of Texas at San Antonio; and one is from the Department of Neurology with the South Texas Veterans Health Care System.

"This study exemplifies team science at its best - multiple scientists and clinicians with complementary expertise working together to make lives better," said Kenneth M. Hargreaves, DDS, PhD, professor and chair of the Department of Endodontics at UT Health San Antonio, and senior author of the paper.

Fatty acids and pain

Chronic pain is a major cause of disability around the world. But although fat-reduction often is advised to manage diabetes, auto-immune disorders and cardiovascular diseases, the role of dietary lipids, or fatty acids, in pain conditions has been relatively unknown.

In the new paper, Dr. Boyd and his colleagues used multiple methods in both mice and humans to study the role of polyunsaturated fatty acids in pain conditions. They found that typical Western diets high in omega-6 polyunsaturated fats served as a significant risk factor for both inflammatory and neuropathic pain.

Omega-6 fats, mainly found in foods with vegetable oils, have their benefits. But Western diets associated with obesity are characterized by much-higher levels of those acids in foods from corn chips to onion rings, than healthy omega-3 fats, which are found in fish and sources like flaxseed and walnuts.

Generally, unhealthy foods high in omega-6 fats include processed snacks, fast foods, cakes, and fatty and cured meats, among others.

Reversal of this diet, especially by lowering omega-6 and increasing omega-3 lipids, greatly reduced these pain conditions, the researchers found. Also, the authors demonstrated that skin levels of omega-6 lipids in patients with Type 2 diabetic neuropathic pain were strongly associated with reported pain levels and the need for taking analgesic drugs.

"This paper is a high-profile contribution for a huge unmet translational need as there are no treatments altering the nature of this neurological disease," said José E. Cavazos, MD, PhD, professor of neurology, assistant dean and director of the National Institutes of Health-designated South Texas Medical Scientist Training Program at UT Health San Antonio.

In an editorial accompanying the paper, Duke University researchers Aidan McGinnis and Ru-Rong Ji wrote, "This comprehensive and elegant study from Boyd et al. may serve as a foundation for new clinical trials and ultimately provide new avenues for the clinical treatment of neuropathies."

Caloric restriction alters microbiome, enhancing weight loss

Researchers at UCSF have found that extreme caloric restriction diets alter the microbiome in ways that could help with weight loss but might also result in an increased population of Clostridiodes difficile, a pathogenic bacterium that can lead to severe diarrhea and colitis.

Such diets, which allow people only 800 calories per day in liquid form, are an effective approach to weight loss in people with obesity. The unexpected results of this study raise the question of how much the microbiome influences weight loss and which bacteria are significant in that process. The study appears in the June 23, 2021, issue of Nature.

"Our results underscore that the role of calories in weight management is much more complex than simply how much energy a person is taking in," said Peter Turnbaugh, PhD, an associate professor of microbiology and immunology and a senior author on the study. "We found that this very-low-calorie diet profoundly altered the gut microbiome, including an overall decrease in gut bacteria."

Turnbaugh and his research team leveraged a clinical trial looking at a very-low-calorie liquid diet. That trial, which resulted in successful weight loss for many of the participants, was led by Joachim Spranger, MD, a professor of endocrinology and metabolic diseases at Charité Universitätsmedizin in Berlin, and co-senior author on the Nature study.

To investigate the microbial connection between this very-low-calorie diet and shedding pounds, Spranger's team collected and sequenced fecal samples from 80 participants - all of whom were post-menopausal women - before and after the trial, which lasted 16 weeks. The team then worked with members of the Turnbaugh lab to analyze the data and to transplant the samples into mice that had been raised in sterile environments.

The researchers allowed these mice to continue eating the same amount of food and found, to their surprise, that the rodents that had received a transplant of the post-diet microbiome lost weight.

"We drove weight loss just by colonizing these mice with a different microbial community," Turnbaugh said.

The next step was to identify bacteria that could be responsible for the weight loss. To do that, Jordan Bisanz, PhD, a former postdoctoral fellow in the Turnbaugh lab and a first author on the study, sequenced the gut microbiomes of the test mice and compared them to those of control mice.

Bisanz discovered a bacterial factor behind changes in weight the team had observed: higher levels of C. difficile.

In the gut, C. difficile is associated with the process of fat metabolism. Initially, fats are digested with the help of bile salts. These bile salts are then broken down by bacteria other than C. difficile, producing what are called secondary bile salts. These bacterial metabolites keep the growth of C. difficile under control. In other words, people who are eating less, particularly less fat, can produce less bile, which in turn leads to fewer secondary bile acids and less of a check on the population of C. difficile.

"Ordinarily we would predict increased inflammation or even colitis following an increase in C. difficile," said Turnbaugh, who is also an investigator at the Chan Zuckerberg Biohub, Curiously, when he and his team examined the mice, they found only mild inflammation. That lack of inflammation suggests that C. diff could have important effects on metabolism that are distinguishable from the bacterium's ability to drive severe intestinal disease.

At the same time, Turnbaugh notes, it's not at all certain what would happen if someone stayed on the diet for a longer period of time and whether that could result in a full-blown C. difficile infection, which can be life threatening if it gets out of control.

"Let's be clear; we are definitely not promoting C. difficile as a new weight loss strategy," said Turnbaugh. "We've got a lot of biology left to unpack here." The data raise a lot of interesting and unexplored questions about what role C. difficile is playing beyond the severe inflammatory conditions associated with it, he said.

It's important to understand whether diet-induced changes to C. difficile level are harmful in humans, and how the balance between different microbial species in the gut is affected by different dietary choices, Turnbaugh said. Ultimately, that knowledge could allow clinicians to add or remove specific microbes in a patient's gut to help maintain a healthy body weight.

"Multiple lines of research shows that the gut microbiome can either hinder or enhance weight loss," said Turnbaugh. "We want to better understand how common weight loss diets might impact the microbiome and what the downstream consequences are for health and disease."

Starting the day off with chocolate could have unexpected benefits

Researchers find time of day eating milk chocolate can impact regulation of body weight

BRIGHAM AND WOMEN'S HOSPITAL

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WHO Frank A. J. L. Scheer, PhD, MSc, Neuroscientist and Marta Garaulet, PhD, Visiting Scientist, both of the Division of Sleep and Circadian Disorders, Departments of Medicine and Neurology, Brigham and Women's Hospital. Drs. Scheer and Garaulet are co-corresponding authors of a new paper published in The FASEB Journal.

WHAT Eating milk chocolate every day may sound like a recipe for weight gain, but a new study of postmenopausal women has found that eating a concentrated amount of chocolate during a narrow window of time in the morning may help the body burn fat and decrease blood sugar levels.

To find out about the effects of eating milk chocolate at different times of day, researchers from the Brigham collaborated with investigators at the University of Murcia in Spain. Together, they conducted a randomized, controlled, cross-over trial of 19 postmenopausal women who consumed either 100g of chocolate in the morning (within one hour after waking time) or at night (within one hour before bedtime). They compared weight gain and many other measures to no chocolate intake.

Researchers report that among the women studied:

• Morning or nighttime chocolate intake did not lead to weight gain;
• Eating chocolate in the morning or in the evening can influence hunger and appetite, microbiota composition, sleep and more;
• A high intake of chocolate during the morning hours could help to burn fat and reduce blood glucose levels.
• Evening/night chocolate altered next-morning resting and exercise metabolism.

"Our findings highlight that not only 'what' but also 'when' we eat can impact physiological mechanisms involved in the regulation of body weight," said Scheer.

"Our volunteers did not gain weight despite increasing caloric intake. Our results show that chocolate reduced ad libitum energy intake, consistent with the observed reduction in hunger, appetite and the desire for sweets shown in previous studies," said Garaulet.

A low Omega-3 index is just as strong a predictor of early death as smoking

A new research paper published in the American Journal of Clinical Nutrition last week showed that a low Omega-3 Index is just as powerful in predicting early death as smoking

WRIGHT ON MARKETING & COMMUNICATIONS

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A new research paper published in the American Journal of Clinical Nutrition last week showed that a low Omega-3 Index is just as powerful in predicting early death as smoking. This landmark finding is rooted in data pulled and analyzed from the Framingham study, one of the longest running studies in the world.

The Framingham Heart Study provided unique insights into cardiovascular disease (CVD) risk factors and led to the development of the Framingham Risk Score based on eight baseline standard risk factors--age, sex, smoking, hypertension treatment, diabetes status, systolic blood pressure, total cholesterol (TC), and HDL cholesterol.

CVD is still the leading cause of death globally, and risk can be reduced by changing behavioral factors such as unhealthy diet, physical inactivity, and use of tobacco and alcohol. Therefore, researchers in this study say biomarkers integrating lifestyle choices might help identify individuals at risk and be useful to assess treatment approaches, prevent morbidity, and delay death.

Among the diet-based biomarkers are fatty acids (FAs), whether measured in plasma or red blood cell (RBC) membranes. The FAs most clearly associated with reduced risk for CVD and for total mortality (i.e., death from any cause) are the omega-3 FAs, EPA and DHA, which are typically found in fish like salmon and herring, as well as omega-3 supplements like fish and algal oil.

In a 2018 report that included 2500 participants in the Framingham Offspring Cohort followed for a median of 7.3 years (i.e., between ages ?66 and 73), the baseline RBC EPA + DHA content [the omega-3 index (O3I)] was significantly and inversely associated with risk for death from all causes.

In fact, individuals with the highest Omega-3 Index were 33% less likely to succumb during the follow-up years compared with those with the lowest Omega-3 Index. Similar associations have been seen in the Women's Health Initiative Memory Study, the Heart and Soul Study, and the Ludwigshafen Risk and Cardiovascular Health Study.

The Omega-3 Index measures the amount of EPA and DHA in red blood cell membranes and is a marker of omega-3 status. An optimal Omega-3 Index is 8% or higher, an intermediate Omega-3 Index is between 4% and 8%, and a low Omega-3 Index is 4% and below. Most Americans have an Omega-3 Index below 4%, which puts them a significantly higher risk of early death.

According to researchers in this study, the finding that any FA-based metric would have predictive power similar to that of the well-established standard risk factors was unexpected, and it suggests that RBC FAs--via imperfectly understood mechanisms--somehow reflects an in vivo milieu that consolidates into one measure the impact on the body of all these standard risk factors.

"It is interesting to note that in Japan, where the mean Omega-3 Index is greater than 8%, the expected life span is around five years longer than it is in the United States, where the mean Omega-3 Index is about 5%. Hence, in practice, dietary choices that change the Omega-3 Index may prolong life," said Michael McBurney, PhD, FCNS-SCN, lead researcher in this study. "In the final combined model, smoking and the Omega-3 Index seem to be the most easily modified risk factors. Being a current smoker (at age 65) is predicted to subtract more than four years of life (compared with not smoking), a life shortening equivalent to having a low vs. a high Omega-3 Index."

"The information carried in the concentrations of four red blood cell fatty acids was as useful as that carried in lipid levels, blood pressure, smoking, and diabetic status with regard to predicting total mortality," said Dr. Bill Harris, who was also an author on this study. "This speaks to the power of the Omega-3 Index as a risk factor and should be considered just as important as the other established risk factors, and maybe even more so."

Statement Following CDC ACIP Meeting from Nation’s Leading Doctors, Nurses and Public Health Leaders on Benefits of Vaccination

 

The following statement has been co-signed by the U.S. Department of Health and Human Services (HHS), Centers for Disease Control and Prevention (CDC), American Academy of Family Physicians (AAFP), American Academy of Pediatrics (AAP), American College of Obstetricians and Gynecologists (ACOG), American College of Physicians (ACP), American Heart Association, American Hospital Association (AHA), American Medical Association (AMA), American Nurses Association (ANA), American Public Health Association (APHA), Association of Public Health Laboratories, Association of State and Territorial Health Officials (ASTHO), Big Cities Health Coalition, Council of State and Territorial Epidemiologists, Infectious Diseases Society of America, and National Association of County and City Health Officials (NACCHO):

“As physicians, nurses, public health and health care professionals, and, for many of us, parents, we understand the significant interest many Americans have in the safety of the COVID-19 vaccines, especially for younger people. Today, the CDC Advisory Committee on Immunization Practices (ACIP) met to discuss the latest data on reports of mild cases of inflammation of the heart muscle and surrounding tissue called myocarditis and pericarditis following COVID-19 vaccination among younger people.

“The facts are clear: this is an extremely rare side effect, and only an exceedingly small number of people will experience it after vaccination. Importantly, for the young people who do, most cases are mild, and individuals recover often on their own or with minimal treatment. In addition, we know that myocarditis and pericarditis are much more common if you get COVID-19, and the risks to the heart from COVID-19 infection can be more severe.

“The vaccines are safe and effective, and they prevent COVID-19 illness. They will help protect you and your family and keep your community safe. We strongly encourage everyone age 12 and older who are eligible to receive the vaccine under Emergency Use Authorization to get vaccinated, as the benefits of vaccination far outweigh any harm. Especially with the troubling Delta variant increasingly circulating, and more readily impacting younger people, the risks of being unvaccinated are far greater than any rare side effects from the vaccines. If you get COVID-19, you could get severely ill and be hospitalized or even die. Even if your infection is mild, you or your child could face long-term symptoms following COVID-19 infection such as neurological problems or diminished lung function.”

“We recommend getting vaccinated right away if you haven’t yet. It is the best way to protect yourself, your loved ones, your community, and to return to a more normal lifestyle safely and quickly.”

Dr. Rachel Levine, Assistant Secretary for Health, U.S. Department of Health and Human Services

Dr. Rochelle Walensky, Director, U.S. Centers for Disease Control and Prevention

Dr. Ada Stewart, MD, FAAFP, President, American Academy of Family Physicians

Dr. Lee Savio Beers, MD, FAAP, President, American Academy of Pediatrics

Dr. Maureen G. Phipps, MD, MPH, FACOG, Chief Executive Officer, American College of Obstetricians and Gynecologists

Dr. George M. Abraham, MD, MPH, FACP, FIDSA, President, American College of Physicians

Dr. Mitchell S. V. Elkind, M.D., M.S., FAAN, FAHA, President, American Heart Association

Richard J. Pollack, President and Chief Executive Officer, American Hospital Association

Dr. Gerald E. Harmon, M.D., President, American Medical Association

Dr. Ernest J. Grant, PhD, RN, FAAN, President, American Nurses Association

Dr. Georges C. Benjamin, MD, Executive Director, American Public Health Association

Scott J. Becker, MS, Chief Executive Officer, Association of Public Health Laboratories

Dr. Michael Fraser, PhD, CAE, FCPP, Chief Executive Officer, Association of State and Territorial Health Officials

Chrissie Juliano, MPP, Executive Director, Big Cities Health Coalition

Janet Hamilton, MPH, Executive Director, Council of State and Territorial Epidemiologists

Dr. Barbara D. Alexander, MD, MHS, FIDSA, President, Infectious Diseases Society of America

Lori Tremmel Freeman, MBA, Chief Executive Officer, National Association of County and City Health Officials

For more information and resources on this rare side effect, visit CDC’s website here.

###

Sleep apnea worsens heart disease, yet often untreated

American Heart Association scientific statement

AMERICAN HEART ASSOCIATION

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DALLAS, June 21, 2021 — Health care experts urge increased awareness of obstructive sleep apnea among people with cardiovascular disease or risk factors such as high blood pressure, according to a new scientific statement from the American Heart Association, published today in Circulation, the Association’s flagship journal.

Obstructive sleep apnea (OSA) occurs in 40% to 80% of people with cardiovascular disease, yet it is under-recognized and undertreated, according to the statement. OSA occurs when an upper airway obstruction causes repeated episodes of disrupted breathing during sleep. Symptoms include snoring, lapses in breathing, fragmented sleep and daytime sleepiness. In general, about 34% of middle-aged men and 17% of middle-aged women meet the criteria for OSA.

“Obstructive sleep apnea can negatively impact patients’ health and increase the risk of cardiovascular events and death. This statement is to encourage increased awareness, screening and treatment as appropriate for sleep apnea,” said Chair of the scientific statement writing group Yerem Yeghiazarians, M.D., FAHA, professor of medicine and the Leone-Perkins Family Endowed Chair in Cardiology at the University of California, San Francisco. 

Risk factors for OSA include obesity, large neck circumference, craniofacial abnormalities, smoking, family history and nighttime nasal congestion. OSA is associated with several cardiovascular complications, as detailed in Figure 2 of the statement:

• high blood pressure – OSA is present in 30-50% of people with high blood pressure, and up to 80% of those who have resistant, or hard-to-treat high blood pressure;
• heart rhythm disorders such as atrial fibrillation and sudden cardiac death;
• Stroke;
• worsening heart failure;
• worsening coronary artery disease and risk of heart attack;
• Pulmonary hypertension (PH) – as many as 80% of people with PH have OSA; and
• Metabolic syndrome and Type 2 diabetes.

While there’s no consensus that screening for OSA alters clinical outcomes, the high prevalence of OSA among people with cardiovascular disease, along with evidence that OSA treatment improves patient quality of life, are reasons to screen and provide treatment, according to the statement writing group.

“Patients report better mood, less snoring, less daytime sleepiness, improved quality of life  and work productivity with OSA treatment,” Yeghiazarians said. “In addition, screening advances have changed how we diagnose and treat obstructive sleep apnea. For example, many patients do not have to go to an overnight sleep study center anymore. There are now sleep devices approved by the FDA that patients use at home and send back to their doctor for assessment. And, while a continuous positive airway pressure (CPAP) machine is one form of treatment, there are numerous therapeutic options - from positional therapy and weight loss to oral appliances and surgery - depending on the cause and severity of someone’s OSA.”

The authors suggest:

• Screening for OSA in patients with resistant or difficult to control hypertension, pulmonary hypertension and atrial fibrillation that recurs despite treatment.
• Screening for OSA via a sleep study for some patients with heart failure, especially if sleep-disordered breathing or excessive daytime sleepiness are suspected.
• Treating patients diagnosed with OSA with available therapies, potentially including lifestyle and behavior modifications and weight loss.
• When possible, treating patients with severe OSA with a CPAP machine.
• Treating mild to moderate OSA cases with oral appliances that adjust the jaw and tongue placement during sleep to prevent obstructed breathing.
• Routine follow-up including overnight sleep testing to confirm if treatment is effective.

“Improvements in home diagnostic tools and more research on ways to identify cardiovascular risk in people with OSA are needed,” Yeghiazarians said. “Still, the overall message is clear: we need to increase awareness about screening for and treating OSA, especially in patients with existing cardiovascular risk factors.”

This scientific statement was prepared by the volunteer writing group on behalf of the American Heart Association’s Council on Clinical Cardiology; the Council on Peripheral Vascular Disease; the Council on Arteriosclerosis, Thrombosis and Vascular Biology; the Council on Cardiopulmonary, Critical Care, Perioperative and Resuscitation; the Stroke Council; and the Council on Cardiovascular Surgery and Anesthesia. 

Potato nutrients can help reduce sodium retention, may help reduce risk of hypertension

New study finds that individuals with higher cardiometabolic risk may benefit from adding more dietary potassium, via potatoes, to a typical American diet

ALLIANCE FOR POTATO RESEARCH AND EDUCATION

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June 21, 2021 -- A new study published in Nutrients investigated the effect of increased dietary potassium from a whole food source--baked/boiled potatoes and baked French fries--or a potassium supplement on blood pressure and other cardiovascular disease risk factors compared to a 'typical American' control diet (lower potassium intake) among 30 pre-hypertensive to hypertensive men and women. Results showed that including baked/boiled potato consumption as part of a typical American diet had the greatest benefit on reducing sodium retention, even more than the supplement, and resulted in a greater systolic blood pressure reduction compared to the control diet. Further, despite commonly held misbeliefs about French fries and their role in heart-healthy lifestyles, the authors observed that a 330-calorie serving of baked French fries, when eaten as part of a typical American diet, had no adverse effect on blood pressure or blood vessel function.

"While significant emphasis is often placed on reducing dietary sodium intakes to better control for blood pressure and cardiovascular disease risk, that's only half of the story," says Connie Weaver, PhD, the primary investigator. "Potassium plays just as an important role, and perhaps the ratio of potassium to sodium is most important in the context of the entire food matrix, as the potato meal resulted in a greater reduction of sodium retention than the potassium supplement alone."

Evidence on the effect of increased dietary potassium on blood pressure from clinical trials is extremely limited, and this is one of the first known controlled feeding interventions investigating dietary potassium as the primary variable of interest.

"It's important to establish clinical trials that follow observational research to establish a causal link between diet and health," notes Weaver. "For example, in this clinical study baked French fries had a null effect on blood pressure, which counters observational findings, at least in the short term, and helps to prioritize the importance of focusing on a total diet approach for maintaining health versus one that overemphasizes avoidance of any single food or food group."

Potatoes comprise roughly 20 percent of the vegetable intake in the American diet and help fill several nutrient gaps, including dietary fiber and potassium.1 Eating just one medium potato meets approximately 10 percent of an adult's daily potassium needs. According to the 2020-2025 Dietary Guidelines for Americans, potassium is an essential nutrient of concern, indicating most Americans aren't consuming enough. The mineral has been linked to improvements in cardiovascular and other metabolic health outcomes - including decreased blood pressure in those with hypertension. Overall, potatoes and French fries represent about 7 percent and 3 percent of potassium intake, respectively, in the United States.1

"Considering Americans fall significantly short in meeting daily potassium intakes, these findings show the importance of promoting, not restricting, whole food good-to-excellent sources of potassium in Americans' diets, like potatoes," Weaver said.

A Closer Look at the Study Methodology, Strengths and Limitations

Participants were randomly assigned to one of four 16-day dietary potassium interventions:

• Control diet including 2300 mg potassium/day (reflective of typical intake, considered to be 'low potassium')
• Control diet + 1000 mg of potassium from potatoes (baked, boiled, or pan-heated with no additional fat)
• Control diet + 1000 mg from baked French fries
• Control diet + 1000 mg from a potassium-gluconate supplement

Each diet was tailored to participants' specific caloric needs while all other nutrients were kept constant. Blood pressure was measured across multiple visits of each phase, and participants also collected daily urine/stool samples to assess potassium and sodium excretion and retention.

The strengths of the study include a highly controlled diet, cross-over design, and excellent compliance. However, the researchers note a few limitations as well, including the study's relatively small sample size, poor retention in study participation and relatively short study duration.

"All clinical studies are faced with limitations; however, despite those found in this study, the rigor of the study design is strong and unlike any other studies that have investigated the effect of a whole food - and potassium - on high blood pressure," Weaver notes. "Through our carefully controlled balance study, we could determine the mechanism by which potatoes reduced blood pressure. Overall, we concluded that boiled or baked potatoes can help reduce systolic blood pressure - and baked French fries have no adverse effects on blood pressure and can be included as part of an overall healthy diet."

The research manuscript, "Short-term randomized controlled trial of increased dietary potassium from potato or potassium gluconate: effect on blood pressure, microcirculation, and potassium and sodium retention in pre-hypertensive-to-hypertensive adults," is published in Nutrients (doi: https://doi.org/10.3390/nu13051610). Authors include Michael Stone, Berdine Martin and Connie Weaver of Purdue University. Funding was provided by the Alliance for Potato Research and Education.