Zinc might help to stave off respiratory infection symptoms and cut illness duration
A zinc supplement might help stave off the symptoms of respiratory tract infections, such as coughing, congestion, and sore throat, and cut illness duration, suggests a pooled analysis of the available evidence, published in the open access journal BMJ Open.
But the quality of the evidence on which these findings are based is variable, and it's not clear what an optimal formulation or dose of this nutrient might be, caution the researchers.
Respiratory tract infections include colds, flu, sinusitis, pneumonia and COVID-19. Most infections clear up by themselves, but not all. And they often prove costly in terms of their impact on health services and time taken in sick leave.
Zinc has a key role in immunity, inflammation, tissue injury, blood pressure and in tissue responses to lack of oxygen.
As a result, it has generated considerable interest during the current pandemic for the possible prevention and treatment of COVID-19 infection.
In response to calls for rapid evidence appraisals to inform self-care and clinical practice, the researchers evaluated zinc for the prevention and treatment of SARS-CoV-2, the virus responsible for COVID-19, and other viral respiratory tract infections.
When that review was published, the results of several relevant clinical trials weren't yet available, so this current review brings the available evidence up to date.
The review includes 28 clinical trials involving 5446 adults, published in 17 English and Chinese research databases up to August 2020. None of the trials specifically looked at the use of zinc for the prevention or treatment of COVID-19.
The most common zinc formulations used were lozenges followed by nasal spraysand gels containing either zinc acetate or gluconate salts. Doses varied substantially, depending on the formulation and whether zinc was used for prevention or treatment.
Pooled analysis of the results of 25 trials showed that compared with dummy treatment (placebo), zinc lozenges or nasal spray prevented 5 respiratory tract infections in 100 people a month.
These effects were strongest for curbing the risk of developing more severe symptoms, such as fever and influenza-like illnesses. But this is based on only three studies.
On average, symptoms cleared up 2 days earlier with the use of either a zinc spray or liquid formulation taken under the tongue (sublingual) than when a placebo was used.
During the first week of illness, participants who used sublingual or nasal spray zinc were nearly twice as likely to recover as those who used placebo: 19 more adults out of 100 were likely to still have symptoms a week later if they didn't use zinc supplements.
While zinc wasn't associated with an easing in average daily symptom severity, it was associated with a clinically significant reduction in symptom severity on day 3.
Side effects, including nausea and mouth/nose irritation, were around 40% more likely among those using zinc, but no serious side effects were reported in the 25 trials that monitored them.
However, compared with placebo, sublingual zinc didn't reduce the risk of developing an infection or cold symptoms after inoculation with human rhinovirus, nor were there any differences in illness duration between those who used zinc supplements and those who didn't.
Nor was the comparative effectiveness of different zinc formulations and doses clear. And the quality, size, and design of the included studies varied considerably.
"The marginal benefits, strain specificity, drug resistance and potential risks of other over-the-counter and prescription medications makes zinc a viable 'natural' alternative for the self-management of non-specific [respiratory tract infections], the researchers write.
"[Zinc] also provides clinicians with a management option for patients who are desperate for faster recovery times and might be seeking an unnecessary antibiotic prescription," they add.
"However, clinicians and consumers need to be aware that considerable uncertainty remains regarding the clinical efficacy of different zinc formulations, doses and administration routes, and the extent to which efficacy might be influenced by the ever changing epidemiology of the viruses that cause [respiratory tract infections]," they caution.
And how exactly zinc might exert its therapeutic effects on respiratory infections, including COVID-19, warrants further research, they conclude.
Drinking alcohol to stay healthy? That might not work, says new study
Ulrich John of University Medicine (Germany), November 2, 2021
Increased mortality risk among current alcohol abstainers might largely be explained by other factors, including previous alcohol or drug problems, daily smoking, and overall poor health, according to a new study publishing November 2nd in PLOS Medicine by Ulrich John of University Medicine Greifswald, Germany, and colleagues.
Previous studies have suggested that people who abstain from alcohol have a higher mortality rate than those who drink low to moderate amounts of alcohol. In the new study, researchers used data on a random sample of 4,028 German adults who had participated in a standardized interview conducted between 1996 and 1997, when participants were 18 to 64 years old. Baseline data were available on alcohol drinking in the 12 months prior to the interview, as well as other information on health, alcohol and drug use. Mortality data were available from follow-up 20 years later.
Among the study participants, 447 (11.10%) had not drunk any alcohol in the 12 months prior to the baseline interview. Of these abstainers, 405 (90.60%) were former alcohol consumers and 322 (72.04%) had one or more other risk factor for higher mortality rates, including a former alcohol-use disorder or risky alcohol consumption (35.40%), daily smoking (50.00%), or fair to poor self-rated health (10.51%). The 125 alcohol abstinent persons without these risk factors did not show a statistically significantly difference in total, cardiovascular or cancer mortality compared to low to moderate alcohol consumers, and those who had stayed alcohol abstinent throughout their life had a hazard ratio of 1.64 (95% CI 0.72-3.77) compared to low to moderate alcohol consumers after adjustment for age, sex and tobacco smoking.
"The results support the view that people in the general population who currently are abstinent from alcohol do not necessarily have a shorter survival time than the population with low to moderate alcohol consumption," the authors say. "The findings speak against recommendations to drink alcohol for health reasons."
John adds, "It has long been assumed that low to moderate alcohol consumption might have positive effects on health based on the finding that alcohol abstainers seemed to die earlier than low to moderate drinkers. We found that the majority of the abstainers had alcohol or drug problems, risky alcohol consumption, daily tobacco smoking or fair to poor health in their history, i.e., factors that predict early death."
Quercetin helps to reduce the risk of pancreatic cancer
Univ. of Hawaii and Univ. of Southern California, November 1, 2021
Quercetin, which is found naturally in apples and onions, has been identified as one of the most beneficial flavonols in preventing and reducing the risk of pancreatic cancer. Although the overall risk was reduced among the study participants, smokers who consumed foods rich in flavonols had a significantly greater risk reduction.
This study, published in the American Journal of Epidemiology, is the first of its kind to evaluate the effect of flavonols – compounds found specifically in plants – on developing pancreatic cancer. According to the research paper, “only a few prospective studies have investigated flavonols as risk factors for cancer, none of which has included pancreatic cancer. “
Researchers from Germany, the Univ. of Hawaii and Univ. of Southern California tracked food intake and health outcomes of 183,518 participants in the Multiethnic Cohort Study for eight years. The study evaluated the participants' food consumption and calculated the intake of the three flavonols quercetin, kaempferol, and myricetin. The analyses determined that flavonol intake does have an impact on the risk for developing pancreatic cancer.
The most significant finding was among smokers. Smokers with the lowest intake of flavonols presented with the most pancreatic cancer. Smoking is an established risk factor for the often fatal pancreatic cancer, notes the research.
Among the other findings were that women had the highest intake of total flavonols and seventy percent of the flavonol intake came from quercetin, linked to apple and onion consumption.
It is believed that these compounds may have anticancer effects due to their ability to reduce oxidative stress and alter other cellular functions related to cancer development.
“Unlike many of the dietary components, flavonols are concentrated in specific foods rather than in broader food groups, for example, in apples rather than in all fruit,” notes the research study. Previously, the most consistent inverse association was found between flavonols, especially quercetin in apples and lung cancer, as pointed out in this study. No other epidemiological flavonol studies have included evaluation of pancreatic cancer.
While found in many plants, flavonols are found in high concentrations in apples, onions, tea, berries, kale, and broccoli. Quercetin is most plentiful in apples and onions.
Researcher explains the psychology of successful aging
University of California at Los Angeles, November 2, 2021
Successful aging can be the norm, says UCLA psychology professor Alan Castel in his new book, "Better with Age: The Psychology of Successful Aging" (Oxford University Press). Castel sees many inspiring role models of aging. French Impressionist Claude Monet, he notes, began his beloved water lily paintings at age 73.
Castel cites hundreds of research studies, including his own, combined with personal accounts from older Americans, including Maya Angelou, Warren Buffett, John Wooden, Bob Newhart, Frank Gehry, David Letterman, Jack LaLanne, Jared Diamond, Kareem Abdul-Jabbar, John Glenn and Vin Scully.
Castel notes that architect Gehry designed conventional buildings and shopping malls early in his career, and decades later designed the creative buildings he would only dream about when he was younger. Others who did much of their best work when they were older include Mark Twain, Paul Cezanne, Frank Lloyd Wright, Robert Frost and Virginia Woolf, he writes.
"There are a lot of myths about aging, and people often have negative stereotypes of what it means to get old," Castel said. "I have studied aging for two decades, and have seen many impressive role models of aging, as well as people who struggle in older age. This book provides both science behind what we can to do age well and role models of successful aging. While some books focus on how to try to prevent or delay aging, 'Better with Age' shows how we can age successfully and enjoy the benefits of old age. I have combined the lessons the psychology of aging teaches us with insights from some of the people who have succeeded in aging well."
Castel cites a 1979 study by Harvard University social psychologist Ellen Langer in which men in their 70s and 80s went to a week-long retreat at a motel that was re-designed to reflect the décor and music from 1959. The men, who were all dependent on family members for their care, were more independent by the end of the week, and had significant improvements in their hearing, memory, strength and scores on intelligence tests. Some played catch with a football. One group of the men, who were told to behave like they were 20 years younger, showed greater flexibility, and even looked younger, according to observers who saw photos of them at the start and end of the week.
In another study, researchers analyzed Catholic nuns' diary entries made in the 1930s and 1940s, when the nuns were in their 20s, and determined their level of happiness from these diaries. More than 50 years later, 75 percent of the most cheerful nuns survived to age 80, while only 40 percent of the least happy nuns survived to 80. The happiest nuns lived 10 years longer than the least happy nuns.
Happiness increases our lives by four to 10 years, a recent research review suggested. "As an added bonus," Castel writes, "those additional years are likely to be happy ones."
Successful aging involves being productive, mentally fit, and, most importantly, leading a meaningful life, Castel writes.
What are the ingredients of staying sharp and aging successfully, a process which Castel says can start at any age? He has several recommendations.
Tips for longevity
Walking or other physical exercise is likely the best method to ensure brain and body health, Castel writes.
In a large 2011 study, older adults were randomly assigned to a group that walked for 40 minutes three times a week or a stretching group for the same amount of time. After six months and again after one year, the walking group outperformed the stretching group on memory and cognitive functioning tests. Too much running, on the other hand, can lead to joint pain and injuries.
In addition, after one year, those who walked 40 minutes a day three times a week showed a 2 percent increase in the volume of the hippocampus—an important brain region involved in memory. Typically, Castel notes, the hippocampus declines about 1 percent a year after age 50. "Walking actually appears to reverse the effects of aging," Castel says in the book.
Balance exercises are proven to prevent falls, can keep us walking and may be the most essential training activity for older adults, Castel writes. Each year, more than two million older Americans go to the emergency room because of fall-related injuries. A 2014 British study found that people who could get up from a chair and sit back down more than 30 times in a minute were less likely to develop dementia and more likely to live longer than those who could not. A good balance exercise is standing on one leg with your eyes open for 60 seconds or more, and then on the other leg. Those who did poorly on this were found in a study to be at greater risk for stroke and dementia.
Like walking, sleep is valuable free medicine. Studies have shown a connection between insomnia and the onset of dementia.
People who speak more than one language are at reduced risk for developing dementia, research has shown; there is some evidence being bilingual or multilingual can offset dementia by five years, Castel writes.
One study found that among people between 75 and 85, those who engaged in reading, playing board games, playing musical instruments and dancing had less dementia than those who did none of those activities. "Lifelong reading, especially in older age, may be one of the secrets to preserving mental ability," Castel writes.
Set specific goals. Telling yourself to "eat healthy" is not very likely to cause a change; setting a goal of "eating fewer cookies after 7 p.m." is better. Similarly, "walk four days a week with a friend" is a more useful goal than "get more exercise" and "call a friend or family member every Friday morning" is better than "maintain friendships."
How can we improve our memory? When Douglas Hegdahl was a 20-year-old prisoner of war in North Vietnam, he wanted to learn the names of other American prisoners. He memorized their names, capture dates, methods of capture and personal information of more than 250 prisoners to the tune of the nursey rhyme, "Old MacDonald Had a Farm." Today, more than four decades later, he can still recall all of their names, Castel writes.
Social connections are also important. Rates of loneliness among older adults are increasing and chronic loneliness "poses as large a risk to long-term health and longevity as smoking cigarettes and may be twice as harmful for retirees as obesity," Castel writes. The number of Americans who say they have no close friends has roughly tripled in the last few decades. There is evidence that people with more social support tend to live longer than those who are more isolated, and that older adults who lead active social lives with others are less likely to develop dementia and have stronger immune systems to fight off diseases. "Staying sharp," Castel writes, "involves staying connected—and not to the Internet."
A 2016 study focused on "super-agers"—people in their 70s whose memories are like those of people 40 years younger. Many of them said they worked hard at their jobs and their hobbies. The hard work was challenging, and not always pleasurable, leaving people sometimes feeling tired and frustrated. Some researchers believe this discomfort and frustration means you are challenging yourself in ways that will pay off in future brain and other health benefits.
Research has shown that simply telling older adults they are taking a "wisdom test" rather than a "memory test" or "dementia screening" actually leads to better results on the identical memory test, Castel writes.
If you are concerned about your memory, or that of a loved one, it may be wise to see a neurologist, Castel advises.
Castel, 42, said he is struck by how many older adults vividly recall what is most important to them.
As Castel quotes the Roman philosopher and statesman Cicero: "No old man forgets where he has hidden his treasure."
Researchers find phthalates in wide variety of fast foods
George Washington University Milken Institute School of Public Health, October 29, 2021
A team of researchers from The George Washington University Milken Institute School of Public Health, the Southwest Research Institute and the Chan School of Public Health, has found phthalates in a wide variety of fast foods. In their paper published in Journal of Exposure Science and Environmental Epidemiology, the group describes how they collected samples of fast food from several restaurants and tested them for phthalates and other chemicals meant to replace them—and what they found.
Phthalates are esters of phthalic acid and are commonly used to make plastic substances more flexible. Prior research has shown that they can also increase durability and longevity making them popular for plastics makers. Researchers have found that consumption of phthalates can disrupt the endocrine system and by extension levels of hormones in the body. Research has also shown that they can lead to asthma in children and increased obesity.
In this new effort, the researchers built on prior work they conducted looking at urine samples of volunteers where they found that those who ate more fast food, tended to have more phthalates in their system. To learn more about the link between fast food and phthalate levels, the researchers visited six fast food restaurants in and around San Antonio, Texas, and collected 64 food items to be used as test samples. They also asked for a pair of the plastic gloves that were used by food preparers at the same establishments and obtained three of them.
In studying the food samples, the researchers found DnBP in 81% of the samples and DEHP in 70% of them. They also noted that the foods with the highest concentrations of phthalates were meat-based, such as cheeseburgers or burritos. The team also found DINCH, DEHT and DEHA, chemicals that have begun replacing phthalates in many of the samples they collected. They note that it is not known if such replacements are harmful to humans if ingested.
The researchers did not attempt to find out how the phthalates were making their way into the fast foods but suspect it is likely from residue on rubber gloves used by cooks who prepare them. It is also possible, they note, that they are coming from plastic packaging.
Removing digital devices from the bedroom can improve sleep for children, teens
Penn State University, November 2, 2021
Removing electronic media from the bedroom and encouraging a calming bedtime routine are among recommendations Penn State researchers outline in a recent manuscript on digital media and sleep in childhood and adolescence.
The manuscript appears in the first-ever special supplement on this topic in Pediatricsa nd is based on previous studies that suggest the use of digital devices before bedtime leads to insufficient sleep.
The recommendations, for clinicians and parents, are:
1. Make sleep a priority by talking with family members about the importance of sleep and healthy sleep expectations;
2. Encourage a bedtime routine that includes calming activities and avoids electronic media use;
3. Encourage families to remove all electronic devices from their child or teen's bedroom, including TVs, video games, computers, tablets and cell phones;
4. Talk with family members about the negative consequences of bright light in the evening on sleep; and
5. If a child or adolescent is exhibiting mood or behavioral problems, consider insufficient sleep as a contributing factor.
"Recent reviews of scientific literature reveal that the vast majority of studies find evidence for an adverse association between screen-based media consumption and sleep health, primarily delayed bedtimes and reduced total sleep duration," said Orfeu Buxton, associate professor of biobehavioral health at Penn State and an author on the manuscript.
The reasons behind this adverse association likely include time spent on screens replacing time spent sleeping; mental stimulation from media content; and the effects of light interrupting sleep cycles, according to the researchers.
Buxton and other researchers are further exploring this topic. They are working to understand if media use affects the timing and duration of sleep among children and adolescents; the role of parenting and family practices; the links between screen time and sleep quality and tiredness; and the influence of light on circadian physiology and sleep health among children and adolescents.