Caffeine jump-starts your day and puts a bounce in your step. It can help you focus, improve your mood and maybe even help you live longer.
But how much is too much?
Caffeine, a natural stimulant, can be found in a variety of foods, such as coffee beans, tea leaves, cacao beans, guarana berries and yerba maté leaves. It also can be synthetically created and added to beverages such as soda and energy drinks. Research shows that about 90% of U.S. adults consume some form of caffeine every day.
One of the most popular ways people consume it is through coffee. Because of that, most caffeine research centers around this drink, said Dr. Greg Marcus, associate chief of cardiology for research and a professor of medicine at the University of California, San Francisco.
Researchers investigated the effects of strength training on bone density in vegans.
They found that vegans who engaged in a form of resistance training such as lifting weights had a similar bone density to omnivores who engaged in weight training.
They recommend vegans include resistance training as a part of a plant-based lifestyle.
Veganism is a growing practice with the number of people following a vegan diet or lifestyle in the United States increasing from around 1% in 2014 to roughly 10% in 2022, as reported in Medical News Today (MNT)
However, in addition to its health benefits, research has also indicated a link between the vegan diet and a higher susceptibility to fractures and low bone mineral density.
A study simulating a population of 30 million people 65 and older found that wrist-wearable devices are more cost-effective than traditional electrocardiograms and pulse palpation for atrial fibrillation (AF) screening, and that they are associated with a reduction in stroke incidence
Researchers believe their findings could provide a rationale for integrating wrist-worn wearables into AF screening programs for populations beginning at age 50, which is well below the typically recommended age of 65
Screening individuals for atrial fibrillation (AF) using wearable devices is more cost-effective than screening using conventional methods such as 12-lead electrocardiogram (ECG) and pulse palpation, or than no screening at all, researchers from Massachusetts General Hospital (MGH) have found.
In a study in JAMA Health Forum, the team reported that use of contemporary wrist-worn wearables was also associated with a reduction in stroke incidence and could help to detect less frequent AF episodes through its ability to monitor for potentially irregular heart rhythm on a near-continuous basis.
Monoamine neurotransmitters such as serotonin and dopamine play important roles in our cognitive and emotional functions. Their evolutionary origins date back to metazoans, and while the function of related genes is strongly evolutionarily conserved, genetic variation within and between species has been reported to have a significant impact on animal mental characteristics such as sociality, aggression, anxiety, and depression.
A research group led by Dr Daiki Sato and Professor Masakado Kawata has previously reported that the vesicular monoamine transporter 1 (VMAT1) gene, which transports neurotransmitters to secretory vesicles in neurons and secretory cells, has evolved through natural selection during human evolution. In particular, the 136th amino acid locus of this gene has evolved in the human lineage from asparagine (Asn) to threonine (Thr), and moreover, a new allele (isoleucine, Ile) has emerged and increased in its frequencies around the world. Previous reports suggested that people with the Ile genotype are less prone to depression and anxiety than those with the Thr genotype, but it was unclear how these human-specific mutations function in the brain and lead to changes in neuropsychiatric behavior.
Social isolation rewires the brain in myriad ways, potentially leading to anxiety, depression, addiction, and other behavioral changes. The findings were presented at Neuroscience 2021, the annual meeting of the Society for Neuroscience and the world’s largest source of emerging news about brain science and health.
Humans are a highly social species who crave social contact for their well-being. Loneliness induced by social isolation can cause significant neurological and behavioral changes that may lead to health issues. Given the widespread experience of loneliness during the COVID-19 pandemic, there is a need to better understand and prevent the long-term effects of social isolation. Scientists are just beginning to understand these changes and hope to find ways to curb their negative effects.
Today’s new findings show:
Young mice exposed to chronic social isolation demonstrated a long-term deficit in social recognition and an altered circuit between the prefrontal cortex and nucleus accumbens (Yong-Seok Lee, Seoul National University College of Medicine).
Social isolation in adolescent mice led to increased cocaine use and relapse rates, as well as sex-dependent structural changes in the prefrontal cortex and nucleus accumbens (Lisa A. Briand, Temple University).
Social isolation in young rats led to an increase in weight, anxiety, and dopamine release in the nucleus accumbens, but exercise mitigated anxiety and weight gain (Enrique U. Pérez-Cardona, University of Puerto Rico at Carolina).
Lower social rank in mice is predictive of greater alcohol intake, but social isolation increases intake for all mice — regardless of rank — and increases the excitability of the basolateral amygdala (Reesha R. Patel, Salk Institute for Biological Studies).
A socially monogamous prairie vole model mimicked human responses after the loss of a partner; these behavioral changes may be linked to disturbances in the brain’s oxytocin system (Adam S. Smith, University of Kansas).
“This research shows that social isolation impacts many brain regions and affects many different behaviors, resulting in increased risk for disease,” said Alexa H. Veenema, the director of the Neurobiology of Social Behavior Laboratory and an associate professor at Michigan State University. “The pandemic has had a tremendous effect on our mental health. This research will provide us with insights about which specific neural circuits mediate the behavioral effects induced by social isolation. We can then find ways to restore these neural circuits, counteracting the consequences of social isolation”
Back in March of 2018 I produced a humor post of apparently steamy paperback book covers that were, in fact, altered and reproduced by librarians. You can revisit them – here is the link. Maybe you remember it. In any event I had occasion to revisit the subject and in exploring them, thought that you might like to see some more. Here they are.
Even moderate physical activity has a positive effect on the brain. DZNE researchers led by Dr. Dr. Ahmad Aziz deduce this from examinations of 2,550 participants of the Bonn “Rhineland Study”. According to their findings, certain areas of the brain are larger in physically active individuals than in those who are less active. In particular, brain regions that have a relatively high oxygen demand benefit from this effect. The research results are published in Neurology®, the medical journal of the American Academy of Neurology.
Exercise keeps body and mind healthy – but little is known about exactly how and where physical activity affects our brains. “In previous research, the brain was usually considered as a whole,” says Fabienne Fox, neuroscientist and lead author of the current study. “Our goal was to take a more detailed look at the brain and find out which regions of the brain physical activity impacts most.”
Taking blood pressure readings from both arms and using the higher reading would more accurately capture who has high blood pressure – and is at increased risk for cardiovascular disease and death – than relying on readings from a single arm, new research suggests.
While current recommendations call for using the higher arm reading, there was previously no evidence in the scientific literature to support the practice, which isn’t routinely followed, according to the study. The findings appeared this week in the American Heart Association journal Hypertension.
“If you are only doing one arm, you can’t know which is the higher-reading arm,” said lead study author Christopher Clark, a clinical senior lecturer in primary care at the University of Exeter Medical School in Devon, England. “And if you don’t catch high blood pressure, you can’t treat it. We can now support the adoption of using the higher reading from both arms.”
Nearly half of U.S. adults have high blood pressure, also known as hypertension. Blood pressure is considered high if the systolic reading – the top number – is 130 mmHg or more, or the diastolic reading – the bottom number – is 80 mmHg or more. High blood pressure is a risk factor for heart disease, heart attacks and strokes.
In a 2019 scientific statement detailing proper blood pressure measurement, the AHA recommended taking readings from both arms during an initial patient visit and using the arm with the higher reading for measurements at subsequent visits. The statement also called for making sure to use the proper cuff size based on the patient’s arm circumference, among other guidance.
Chemicals produced by microbes in the digestive tract may be partly responsible for the increased heart disease risk associated with higher consumption of red meats such as beef and pork, a new study suggests, according to the American Heart Association (AHA).
Cardiovascular disease – which includes heart attacks and strokes – is the leading cause of death in the U.S. and around the world. As people age, their cardiovascular disease risk increases.
But risks can be lowered by eating a diet emphasizing fruits and vegetables, legumes, nuts, whole grains, lean protein and fish, staying physically active, getting enough sleep, maintaining a healthy body weight, not smoking and properly managing blood pressure, cholesterol and blood sugar levels.
“Most of the focus on red meat intake and health has been around dietary saturated fat and blood cholesterol levels,” study co-author Meng Wang said in a news release. Wang is a postdoctoral fellow at the Friedman School of Nutrition Science and Policy at Tufts University in Boston.
“Based on our findings, novel interventions may be helpful to target the interactions between red meat and the gut microbiome to help us find ways to reduce cardiovascular risk,” she said.
Let’s not beat around the bush: Blueberries are good for you according to the American Heart Association.
This will come as no surprise to many Americans, who have found their thrill with blueberries in ever-rising numbers. It’s easy to understand why. Not only do they taste great, but studies keep suggesting more reasons to embrace them.
“They’re the kind of things we should be eating,” said Eric Decker, professor of food science at the University of Massachusetts Amherst. “But sometimes these things get overpromised.”
Vaguely defined terms such as “superfood” get used a lot with blueberries, whose popularity has been fueled by careful marketing. “Anytime you start talking about ‘superfoods’ and ‘super fruits,’ it’s probably a little overexaggerated,” Decker said.
People with a condition that restricts blood flow to the legs and feet may be able to improve their long-term walking ability by walking for exercise at a pace that feels painful or uncomfortable, new research suggests.
The study, published Wednesday in the Journal of the American Heart Association, found people with peripheral arterial disease, or PAD, who walked at a speed that caused painful symptoms increased their walking speed and leg function more than those who walked for exercise at a more comfortable pace.
“We were surprised by the results because walking for exercise at a pace that induces pain in the legs among people with PAD has been thought to be associated with damage to leg muscles,” senior study author Dr. Mary McDermott said in a news release. She is a professor of medicine and preventive medicine at Northwestern University’s Feinberg School of Medicine in Chicago.
“Exercise that induces leg pain is beneficial, though difficult,” she said. “We now are working to identify interventions that can make the higher intensity exercise easier – and still beneficial – for people with PAD.”
An estimated 8 to 10 million U.S. adults have PAD, a condition characterized by reduced blood and oxygen flow stemming from a narrowing of the arteries that take blood from the heart to the rest of the body. The condition typically affects the legs and feet, causing symptoms during walking such as cramping, weakness, fatigue, aching, and pain or discomfort that fade within 10 minutes after resting.
If you’re 45 years old, that means that you’ve completed 45 rotations around the sun. But, how old are you really?
Humanity has been interested in slowing the aging process and finding the “fountain of youth” since the dawn of time, but conversations about longevity are especially relevant as life expectancy in the U.S. has decreased by more than a year since 2020.
“Thanks to science, the mysteries of aging are now being revealed,” says Douglas E. Vaughan, MD, chair of Medicine and the Irving S. Cutter Professor of Medicine at Northwestern University Feinberg School of Medicine, and co-director of Potocsnak Longevity Institute at Northwestern Medicine with Northwestern Medicine Infectious Disease Physician Frank J. Palella, MD. “The biology that drives the aging process is being demystified right in front of our eyes to the point that it’s conceivable to think about slowing the pace of aging, turning the clock back and altering the course of someone’s lifespan.”
Biological Versus Chronological Age
Chronological age is how long you have existed. Biological age is how old your cells are.
Sometimes these two numbers are the same for people, but everyone ages at different rates.
Your healthspan is the period of life where you are free of any aging-related disease. Dr. Vaughan and the Potocsnak Longevity Institute are aiming to increase the human healthspan by slowing down the aging process to push back the onset of aging-related diseases.
For many diseases, the most important risk factor is biological age, meaning that if your cells are older, they are more susceptible to a variety of diseases, such as:
“For most people, if you live long enough, you’re going to get an aging-related disease like high blood pressure,” says Dr. Vaughan. “There’s a quantifiable alteration and deterioration in function as you age.”
Aging on a Cellular Level
You can see some signs of aging with the naked eye — gray hair, wrinkles, limited mobility — but aging really happens on a cellular level.
As your cells age, they eventually enter a phase called senescence, when they lose their ability to regenerate and repair themselves. Environmental factors like stress, or genetic factors like family history can trigger senescence in your cells.
“In the last 20 years, we have unraveled the biology of senescence to the point where we are able to see a fingerprint of the molecular markers of biological age,” says Dr. Vaughan.
Chromosomes are structures that carry your DNA, which is the blueprint for your cells. Telomeres are groups of molecules called nucleotides on the ends of your chromosomes that act like bumpers, protecting your chromosomes from deterioration.
Every time your cells divide for normal repair and regeneration (which is all the time), your telomeres get shorter, which means they get shorter as you age. Research suggests that if you have shorter telomeres, you are more likely to die early or develop a disease like a neurodegenerative disorder.
In fact, there are people with short telomere syndromes (STS) who have genetic mutations that result in rapid aging due to short telomere lengths.
Humans have an estimated 30,000 genes, which carry the instructions for making proteins that make up your body and carry out all of its functions. Genes can be turned on or off like light switches. When your cells replicate and repair, a process called DNA methylation can occur. DNA methylation doesn’t alter or mutate your genes, but instead changes how you express your genes.
In short, DNA methylation can turn your genes on or off.
Examining DNA methylation is part of epigenetics, the study of how your genes are expressed based on your lifestyle and environment. This is important, because you don’t age in a vacuum. A variety of external factors contributes to how you age, including lifestyle, stress and even access to health care.
DNA methylation can also be a very precise predictor of your biological age.
“Someone who has diabetes will have a very different DNA methylation pattern than someone who doesn’t. Someone who smokes cigarettes will have a different DNA methylation pattern than someone who doesn’t,” says Dr. Vaughan. “DNA methylation can be reversed by lifestyle changes. You can alter your fate with diet and exercise, for example.”
Your actual age
Scientists may be able to measure your biological age in the not-so-distant future.
“We are not far away from having very precise measures that allow us to determine someone’s biological age,” says Dr. Vaughan. “We’re optimistic that we’ll soon be able to tinker with the biology of aging so that people can live longer healthspans.”
Heart health and your health in general are clearly tied to your psychological health. It should come as no surprise to regular readers here that eat less; move more; live longer works.
The American Heart Association has released a scientific statement addressing how psychological health can contribute to cardiovascular disease (CVD). Their analysis of science to date concluded that negative psychological health (depression, chronic stress, anxiety, anger, pessimism, and dissatisfaction with one’s current life) is linked to CVD risk and may play a direct role in both biological processes and downstream lifestyle behaviors that cause CVD. Conversely, positive psychological health can contribute to better cardiovascular health and reduced cardiovascular risk.The majority of research suggests interventions to improve psychological health can have a beneficial impact on cardiovascular health.
Get regular health check-ups that include basic screening for psychological health and seek help from a mental health professional if you have concerns. The study also recommends exercise, meditation, and other self-care as potential ways to promote both mental and physical health.
Napping, as well as sleeping too much or too little or having poor sleep patterns, appears to increase the risk for cardiovascular disease in older adults, new research shows.
The study, published Tuesday in the Journal of the American Heart Association, adds to a growing body of evidence supporting sleep’s importance to good health. The American Heart Association recently added sleep duration to its checklist of health and lifestyle factors for cardiovascular health, known as Life’s Essential 8. It says adults should average seven to nine hours of sleep a night.
“Good sleep behavior is essential to preserve cardiovascular health in middle-aged and older adults,” said lead author Weili Xu, a senior researcher at the Aging Research Center in the department of neurobiology, care sciences and society at the Karolinska Institute in Stockholm, Sweden. “We encourage people to keep nighttime sleeping between seven to nine hours and to avoid frequent or excessive napping.”
Prior research has shown poor sleep may put people at higher risk for a range of chronic illnesses and conditions affecting heart and brain health. These include cardiovascular disease, dementia, diabetes, high blood pressure and obesity. According to the Centers for Disease Control and Prevention, nearly 35% of U.S. adults say they get less than seven hours of sleep, while 3.6% say they get 10 or more hours.
Previous sleep duration studies show that sleeping too much or too little both may raise the risk for cardiovascular disease. But whether napping is good or bad has been unclear.
In the new study, researchers analyzed sleep patterns for 12,268 adults in the Swedish Twin Registry. Participants were an average of 70 years old at the start of the study, with no history of major cardiovascular events.
A questionnaire was used to collect data on nighttime sleep duration; daytime napping; daytime sleepiness; the degree to which they considered themselves a night person or morning person, based on the time of day they considered themselves most alert; and symptoms of sleep disorders, such as snoring and insomnia. Participants were followed for up to 18 years to track whether they developed any major cardiovascular problems, including heart disease and stroke.
People who reported sleeping between seven and nine hours each night were least likely to develop cardiovascular disease, a finding in keeping with prior research. Compared with that group, those who reported less than seven hours were 14% more likely to develop cardiovascular disease, and those who reported more than 10 hours were 10% more likely to develop cardiovascular disease.
Compared with people who said they never napped, those who reported napping up to 30 minutes were 11% more likely to develop cardiovascular disease. The risk increased by 23% if naps lasted longer than 30 minutes. Overall, those who reported poor sleep patterns or other sleep issues – including insomnia, heavy snoring, getting too much or too little sleep, frequent daytime sleepiness and considering themselves a night person – had a 22% higher risk
Study participants who reported less than seven hours of sleep at night and napping more than 30 minutes each day had the highest risk for cardiovascular disease – 47% higher than those reporting the optimal amount of sleep and no naps.
The jury is still out on whether naps affect cardiovascular risk across the lifespan, said Marie-Pierre St-Onge, center director for the Sleep Center of Excellence and an associate professor at Columbia University in New York City. She noted that the new research, which she was not involved in, was restricted to older adults.
Rather than trying to recoup sleep time by napping, people should try to develop healthier sleep habits that allow them to get an optimal amount of sleep at night, St-Onge said. This includes making sure the sleep environment is not too hot or cold or too noisy. Reducing exposure to bright light before going to sleep, not eating too late at night, getting enough exercise during the day and eating a healthful diet also help.
“Even if sleep is lost during the night, excessive napping is not suggested during the day,” Xu said. And, if people have persistent trouble getting enough sleep, they should consult a health care professional to figure out why, she said.
What are the chances you will contract Covid-19 on a plane flight? A study led by MIT scholars offers a calculation of that for the period from June 2020 through February 2021. While the conditions that applied at that stage of the Covid-19 pandemic differ from those of today, the study offers a method that could be adapted as the pandemic evolves.
The study estimates that from mid-2020 through early 2021, the probability of getting Covid-19 on an airplane surpassed 1 in 1,000 on a totally full flight lasting two hours at the height of the early pandemic, roughly December 2020 and January 2021. It dropped to about 1 in 6,000 on a half-full two-hour flight when the pandemic was at its least severe, in the summer of 2020. The overall risk of transmission from June 2020 through February 2021 was about 1 in 2,000, with a mean of 1 in 1,400 and a median of 1 in 2,250.
To be clear, current conditions differ from the study’s setting. Masks are no longer required for U.S. domestic passengers; in the study’s time period, airlines were commonly leaving middle seats open, which they are no longer doing; and newer Covid-19 variants are more contagious than the virus was during the study period. While those factors may increase the current risk, most people have received Covid-19 vaccinations since February 2021, which could serve to lower today’s risk — though the precise impact of those vaccines against new variants is uncertain.
Still, the study does provide a general estimate about air travel safety with regard to Covid-19 transmission, and a methodology that can be applied to future studies. Some U.S. carriers at the time stated that onboard transmission was “virtually nonexistent” and “nearly nonexistent,” but as the research shows, there was a discernible risk. On the other hand, passengers were not exactly facing coin-flip odds of catching the virus in flight, either.