UF Health Podcasts

Stepping inside a perfectly air-conditioned room during the summer sends a pleasant tingle across your skin. It’s refreshing, and a sensation whose mechanisms are now becoming less of a mystery.

A new study in mice from researchers at the University of Michigan is shedding light on how your skin knows the temperature is cool outside — and why your brain cares. The team successfully “traced” the entire pathway that handles cool temperatures, from skin to brain, making it the first time scientists have fully mapped a temperature-sensing neural circuit. Notably, cooler temperatures have their own dedicated neural pathway, meaning your body doesn’t just lump “not-hot” into one category. Rather, it evolved separate routes to detect hot and cold.

Here’s how it works: When the skin feels something in the 59 to 77°F range, tiny molecular “thermometers” get triggered. These activate primary sensory neurons, which ping the spinal cord. There, a previously unknown player steps in: an amplifier neuron, whose job it is to prevent the signal from getting lost in the noise. Then, the signal zooms up to the brain, giving you that delicious “ahh” moment when a cool breeze brushes by on a hot day.

Why does this matter? Well, more than 70% of people on chemo report cold-induced pain, which can happen soon after an infusion. Because the pathway studied here is not involved in that particular type of pain, understanding it better could help scientists figure out which kind is, and how to fix it — without affecting your ability to enjoy the crisp AC during a grocery store run. And, because we must say it: That sounds pretty cool.

Scores of Americans increase exercise in the fight to lose weight. Yet, scientists say sedentary behavior isn’t the primary cause of the American obesity epidemic. For that, look to the scourge of the modern supermarket — processed foods.

Indeed, scientists say Americans actually burn more calories than people in developing countries living traditional lifestyles.

A study by scientists at Duke University analyzed data from 34 different populations around the world, totaling more than 4,000 people. These included everyone from Norwegian office workers to Tanzanian hunter-gatherers.

Participants’ physical activity was tracked, and the data offered some surprising findings.

Scientists saw that energy expenditure in developed countries is higher than in developing nations, which was unexpected. Sedentary behavior is often associated with wealthier nations. This finding contradicts the idea that less physical activity is linked to obesity.

In the 25 nations where dietary data is available, the study found that those who ate ultraprocessed foods were, on average, heavier.

These foods include packaged cookies or cakes, ice cream with preservatives, processed meats like hot dogs or luncheon meats, and sugary drinks.

This finding, by itself, isn’t surprising. But it is when coupled with the increased energy consumption in nations where obesity is more prevalent.

None of this suggests you shouldn’t exercise anyway. Doing so prevents heart disease, improves mental health and extends life. And burning calories on a treadmill or bicycle still helps you lose weight … although perhaps not as much as any of us would like.

In case you need to hear it: Drinking alcohol at any age is harmful to our health. And, once you turn the page to 65 years old, drinking comes at an even greater cost.

Because older adults tend to have less muscle mass and retain less water in their tissues, imbibing a cocktail or other drink of choice can send their blood alcohol concentration soaring. This means it takes fewer drinks to feel intoxicated. And, though you can stumble at any age, inebriation for older adults leads to a risk of severe injury … and often a long recovery.

A federal survey reported that 12% of older adults reported indulging in at least four drinks during a single sitting over the past month. That number comes out to about 7 million people.

For even the most active among us, alcohol affects nearly every organ system in the body. This includes muscles, blood vessels, the digestive system, the heart and the brain. Drinking alcohol also increases our chances of developing chronic conditions, like dementia, diabetes, cancer, hypertension and heart disease. One key point: It worsens outcomes for older folks dealing with chronic disease.

It’s also important to keep any prescription medications for conditions like diabetes in mind. When the alcohol mixes with the medication, the latter becomes less effective and the side effects can cause a host of issues.

Experts also recommend that adults 65 and older should consume no more than one drink per day and no more than seven per week. Although abstinence doesn’t have to be the answer, those committed to aging healthily should try to avoid multiple drinks in a day.

If you think about it, that’s a small price to pay for a better quality of life — today and tomorrow.

You’re sitting at the airport, filled with excitement. People pass by laden with suitcases. Someone sprints behind you, desperate to make a connecting flight. You’re one airborne nap away from some much-needed rest and relaxation.

As you board the plane and take your seat, you notice a fussing baby a few rows over. Your seatmate is playing games on his phone with the sound on. The flight attendant’s voice crackles over the announcement system. You settle in, prepared to endure this oh-so-human cacophony in order to start your vacation.

But it’s the sound we often don’t notice that we might need to pay more attention to.

Despite its ability to fade into the background, the airplane’s engine noise is far from quiet. Inside an airplane’s cabin, the noise typically hovers between 75 and 85 decibels. But during takeoff and landing, the engines can peak at more than 110 decibels. Every three-decibel surge corresponds to double the intensity of the sound reaching our ears. And, for a baseline: Fifty years ago, the National Institute for Occupational Safety and Health set sound exposure recommendations of 85 decibels for an eight-hour shift for workers. Now, experts say prolonged noise can also be a risk to our hearing.

What can you do? Well, consider your seat location. Avoid seats near the wings and the rear of the plane, as they’re closer to the engines. Earplugs and head phones can help, as can drinking fluids. By sipping water, you lessen the feeling of ear pressure changes whose discomfort can be amplified by the noise.

So plug in, drink up and enjoy the flight. You’re almost there.

The decision to bring a new pet into your household is a big one, not to be taken lightly. Whether you’re considering a cat, a dog, or some other species, you’ll want to be sure your lifestyle is conducive to meeting the pet’s needs. You should also prepare to make some adjustments to your environment, schedule and finances. It’s important that the pet’s needs be met, but you also need to be able to cover the expenses of responsible pet ownership, from food to veterinary care when needed. On this archived episode of Animal Airwaves Live, Dr. Wendy Mandese, a primary care and dentistry veterinarian, will cover what you need to know before and after you offer a forever home to a new family member.

Losing weight in your 40s can help you fit back into your favorite-but-increasingly-snug-jeans. Beyond flattering your figure, however, midlife weight loss carries a host of other benefits — like adding years to your life.

A recent study found even modest weight loss in your 40s can significantly reduce your risk of developing serious health issues and increase life expectancy. Researchers tracked more than 23,000 adults in their 40s for up to 35 years, gaining insight into the effects of midlife weight loss. Participants who went from overweight to a healthy weight saw a 48% reduced risk of chronic disease and a 19% lower risk of death.

Notably, even modest weight loss was shown to significantly reduce the risk of developing serious health issues while still conveying the benefits of a longer life.

The study was conducted before many of today’s newest surgical and medicinal weight loss interventions were available. That means the study results apply to those who lost weight the old-fashioned way — via diet and exercise.

Losing weight and keeping it off can be a challenge, but researchers emphasized the benefits of putting in the work. As an added incentive, the study found that those who lost weight also typically had lower blood pressure and cholesterol compared with those who remained overweight.

But patience is key. Researchers noted that realizing the full benefit of even modest weight loss in your 40s can take decades to be realized.

So, if you’ve noticed your jeans fitting a bit tighter, know that losing weight could be more than just a cosmetic improvement. It just might be a step toward a longer, healthier life — and it’s never too late to get in shape.

This is a story of tomb curses and a deadly fungus. It’s also a lesson in how science, funded by the federal government, provides hope in the search for new treatments against a cancer that can strike anyone, leukemia.

The fungus is Aspergillus flavus (Pronounced ASS-per-JILL-us FLAY-vus), or A. flavus (A FLAY-vus). It grows worldwide, even in the inky darkness of the tomb.

In the 1920s, a series of untimely deaths by the team that opened the tomb of King Tutankhamun (TOO-tan-KAH-mun) created the myth of a curse that followed anyone entering Tut’s burial chamber.

Decades later, some suggested the curse was actually the work of A. flavus, which is toxic and sometimes deadly.

Then, in the 1970s, a group of 12 scientists entered the tomb of the 15th Century Polish king, Casimir IV (KAZ-uh-meer the Fourth), in Kraków after receiving permission from the local archbishop. Within months, 10 were dead. Again, talk turned to a deadly curse. But scientists found A. flavus around the king’s remains.

More recently, a team led by University of Pennsylvania scientists on the hunt for cancer-killing compounds had a look at this fungal villain. Not a bad idea, considering mold gave us penicillin.

The team’s recent study shows that compounds in the fungus can be modified to enhance its anticancer properties.

Essentially, these modified compounds might block the uncontrolled cell division that is cancer’s signature. The molecules identified were shown to affect leukemia cells.

The researchers say they’re explorers, learning how to defeat disease from nature’s pharmacy. While it’s no supernatural solution, there is poetic justice in working toward a possible cure for the future from a (debunked) curse of the past.

You’ve flossed your teeth and are putting final touches on your makeup when you get an alert letting you know your stress is off the charts.

In a brilliant twist on multitasking, scientists at Tufts University say they have created a dental floss with that can sense and measure the stress hormone cortisol in saliva.

And it does so with extreme accuracy. Down to forty-eight thousandths of picograms (PEE-koh-gram) per milliliter. A picogram, in case you were wondering, is one-trillionth of a gram.

While the product is in its infancy, smart floss could be a game-changer in stress testing. Chronic stress is a big health problem. It contributes to heart disease, mental health issues and weakens immunity.

Doctors typically measure a patient’s stress with psychiatric tests or questionnaires. But some become nervous around doctors and the results aren’t necessarily scientific.

For a more exact measure, the gold standard recommendation is for a patient to take a blood test. While accurate, that’s hardly convenient.

Here’s how the floss works: The FDA-approved suture thread contains tiny molecular templates designed to recognize cortisol. When cortisol binds to them, it alters the sensor’s electrical signal.

In its current state, the signal goes to a small portable device for analysis. For consumers, a much smaller version of the device must be developed. And it needs to be tested by home users, rather than in a lab.

Still, the researchers believe smart floss could someday be used to screen for a host of health issues from the comfort of our bathroom. And that kind of convenience is a stress buster.

Papa and Nana may be lighting up, and they aren’t the only ones.

Record numbers of older adults are getting high on marijuana. A recent New York University analysis of survey results found that in 2023, 7% of adults 65 and older reported using marijuana in the past month.

That number is up almost 46% from 2021, when just 4.8% reported using cannabis.

Back in 2006 and 2007, only about 1% of older adults reported using the drug in the past month.

The trend is hardly surprising: Most Americans now live in a state that has legalized marijuana use for medical or recreational use. Or both.

It’s important because many adults with chronic diseases, including heart disease, diabetes, cancer and high blood pressure, reported using marijuana, which can complicate the management of those diseases.

The study relied upon answers from more than 15,000 people who took part in the National Survey on Drug Use and Health.

The NYU researchers noted sharper increases in marijuana use by white, married, college-degree holders and those with an income of at least $75,000 a year.

Older women also saw a steep increase in use, although older men remain more likely to use the drug.

The researchers made no judgment about whether older adults’ increasing marijuana use is good or bad. But they noted that the physiological changes accompanying aging can include more sensitivity to psychoactive substances, so using the drug can be dangerous if the user isn’t aware of the risks.

Also important to know: Marijuana can also interact with prescription medicines in a way that may cause unwanted side effects or make them less effective.

An unorthodox combination may someday help relieve cancer patients’ depression and anxiety.

A treatment with one dose of psilocybin [sai-luh-sai-bin] — a psychedelic, natural chemical found in mushrooms — along with therapy, gave cancer patients relief from depression and anxiety for more than two years.

In the phase 2 clinical trial in Maryland, 28 patients with cancer and major depression had supervision and support from a therapist before, during and after one “trip” on a 25-milligram dose of psilocybin. The study was published in the journal Cancer.

That dose is enough to cause hallucinations and other effects, such as altered consciousness, visual distortion and deep introspective thoughts, for several hours.

Cancer is a life-threatening diagnosis. Estimates of how many cancer patients also then live with anxiety or depression, or both, range between 20 and 50%.

Of the patients in the study, 54% showed a significant reduction in their depression, as noted in clinical interviews two years later. And 50% saw a  sustained reduction in their depression and were in remission. Forty-three percent of the patients reported reduced anxiety after two years.

An ongoing randomized, double-blind trial is now evaluating how two 25-milligram doses of psilocybin work against depression and anxiety versus a placebo.

The mental strain of depression and anxiety can affect how well one follows medical treatment as well as quality of life. Other studies have found that being depressed results makes dying from cancer more likely.

So, while it may feel like a throwback to the 1960s, the method may be a modern way to help cancer patients.