Valentine’s Day is a time when many of us reflect on the importance of our closest relationships. Whether they include family, friends or a significant other, science is not silent on the impact these relationships have on our health. A review of 148 studies reveals that strong social relationships are associated with a 50 percent increased likelihood of survival, regardless of medical condition. Other studies link low social support to an increased risk and incidence of heart disease. The newest research, however, explores the effect our most intimate relationships—with a romantic partner—have on heart health.
A study that looked at more than 6,000 people reports that being single is associated with heart disease. Specifically, people who were single had a 45 percent higher rate of death from heart disease than those who were married. A striking finding in this study was that even though the reason for being unmarried varied among the participants—some people had never married, others were divorced, separated or widowed—the risks were consistently lower in married people. From these results, the overall benefit of the spousal relationship on heart health seems clear.
Many factors may account for the positive effect of marriage on heart health, including:
- improved social support,
- a less sedentary lifestyle, and
- increased motivation to make healthy lifestyle changes.
The quality of marital relationships over time also influences heart disease risk factors. Men who described their relationships as “improving” had a lowering of risk factors compared to those in marriages categorized as “consistently good” or “deteriorating.”
In other words, marriage is generally good for your heart health and even better when you work to improve that relationship over time. So as you think about those closest to your heart on Valentine’s Day, do your heart a favor and take your sweetheart on a date.
Shawn Bender, PhD, is an assistant professor at the University of Missouri and a research health scientist at the Harry S. Truman Memorial Veterans’ Hospital.
When young people think about their muscles, they often focus on enhancing their muscle size and strength for cosmetic or athletic reasons. Those older than 50, however, need to be more concerned with just keeping the muscle they have. On average, people over the age of 50 lose 1 to 2 percent of their muscle mass each year, and after age 60, this number increases to 3 percent. Bed rest, lack of exercise and sedentary behavior in the elderly can speed up this gradual loss over time. Why is maintaining muscle so important for the elderly?
The simplest reason is that muscle is essential for all kinds of movement. Mobility is a crucial component of maintaining independence as we age. Adequate muscle mass and strength allow seniors to continue performing simple daily activities—things like bathing, getting dressed and preparing food—without assistance. Another less obvious reason is that muscle burns a large percentage of the energy that we get from the foods we eat. Losing muscle mass means that we do not use the energy from food as effectively, which can lead to chronic health conditions. In fact, loss of muscle mass is a major contributor to the increased rates of type 2 diabetes in older adults.
Current research has revealed, however, that muscle size is not the only, or even best measure of muscle health. Scientists have traditionally used the term “sarcopenia” to refer to aged-related loss of muscle mass, but many scientists are now focusing more on “dynapenia,” which indicates the loss of muscle function due to aging. New research is showing that how well muscle works can be just as important as how much muscle mass remains. In fact, a person with a smaller amount of muscle mass whose muscle function is good may be stronger and healthier than someone with more muscle mass but poor muscle function. This realization has led to new strategies for promoting muscle health in aging. Although maintaining muscle mass is still important, new approaches are targeting improvement in muscle function. These strategies go beyond simply lifting weights and look at ways to make the inner machinery of the muscle work better. Although nothing can completely stop the loss of muscle function with age, promising new nutritional and exercise therapies are emerging to substantially slow the decline, helping seniors stay active and independent for as long as possible.
Benjamin Miller, PhD, is an associate professor in the department of Health and Exercise Science at Colorado State University. He co-directs the Translational Research in Aging and Chronic Disease (TRACD) Laboratory.
Another physiology-filled year on the I Spy Physiology blog is almost over. This year, we’ve explored dozens of topics, ranging from skin cancer, gut health and spinal cord injury to the mystery of how hibernating animals’ muscles remain strong. We’ve celebrated women in science and smiled at the thought of turkeys running on treadmills. Today, we’re highlighting the 10 most-read posts of 2017.
Scholarly articles highlight the need for more research about women’s responses to illness and disease risk. In that vein, our most popular post this year looked at the relationship between sex-specific hormones and asthma. Posts about the danger of e-cigs—especially in the under-21 set—and how muscle rebuilds during the daunting feat of cycling the 500-mile Colorado Trail rounded out the top three. Take a look at this year’s top 10:
- When Hormones Take Your Breath Away
- The Trouble with E-Cigs: Why They May Pose More Harm than Good
- Muscle Rebuilding on the Colorado Trail
- Beer Does a Body Good?
- Meet Karyn Hamilton, Health and Exercise Science Professor
- Dog Gazing: Bond between Hound and Human
- Why Does Air Pollution Affect More Women than Men?
- When Vampires Attack: How Your Body Reacts to Extreme Blood Loss
- Microvesicles and Blood Vessels and Exercise, Oh My!
- The Hispanic Paradox: Why Are Some Ethnic Groups Living Longer than Others?
We’d love to hear what you’d like us to feature next year. Share your thoughts in the comments or send us an email. And don’t forget to follow our blog in 2018.
– Erica Roth
If you tend to see the proverbial glass as half empty instead of half full, you may want to rethink your position. Looking on the bright side and expecting good things to happen may have a positive effect on your physical health. An optimistic outlook on life may reduce your cardiovascular disease risk, lower blood pressure and improve overall health and longevity. It can also reduce sensitivity to pain and may help people manage chronic pain more easily.
You may be skeptical or cautiously optimistic about this. How can simple optimism lead to good health? The answer is still not entirely clear, but scientists are slowly uncovering the biological details. They’ve learned that the body’s response to stress may be an important factor.
When the body is stressed, it sends biological messengers called stress hormones into the bloodstream to tell different organs to respond in various ways. One of the major stress hormones is cortisol. When cortisol is high, the body responds by making unhealthy amounts of certain substances (such as cholesterol) that can harm the heart. These substances may damage and cause inflammation in the blood vessels. Inflammation may also lead to more damage in the circulatory system. This unfavorable chain of events may increase the risk of heart disease.
People who look on the bright side may be more likely to have markers of good health—including lower stress hormone levels—even when they face stressful situations. One study found rats with pessimistic behavior traits had more inflammation than their optimistic counterparts. Lower cortisol and inflammation levels may be due to decreased activity of the fight-or-flight nervous response, although more research is needed.
Motivation may also play a role in boosting the health of optimists. People who think positively may be more motivated and tend to make more of an effort in social interactions than those who are pessimistic. This can lead to healthier social connections and an increase in beneficial behaviors such as exercising regularly and following a healthy diet. The motivational aspects of optimism (or pessimism) may also affect a person’s behavioral response to stress.
December 21 is “Look on the bright side” day. Try a visualization exercise to boost your optimism. It may have a positive effect on your overall health.
– Audrey Vasauskas
Shaina Willen, MD, of Vanderbilt University Medical Center, presents her poster at the Physiological and Pathophysiological Consequences of Sickle Cell Disease conference.
Sickle cell disease (SCD) is a lifelong disorder of the red blood cells. It’s caused by a mutation in a single gene and affects about 100,000 people in the U.S. Normal red blood cells are round, a shape that helps the cells carry oxygen around the body. But red blood cells in people with SCD can become abnormally shaped like a crescent (sickle), which can cause blood cells to get stuck in blood vessels and interfere with blood flow, leading to severe pain.
Scientists and medical doctors who specialize in SCD gathered last month in Washington, D.C., for the American Physiological Society conference “Physiological and Pathophysiological Consequences of Sickle Cell Disease.” They discussed new research into the causes of the disease and new therapies that can treat and even prevent SCD-related pain episodes. Read on to learn more about their findings.
Certain patients with SCD may have a higher risk than others of developing complications—such as increased pain, stroke, eye problems and kidney disease—but finding out which patients have a higher risk is challenging. New research from Vanderbilt University Medical Center has uncovered a genetic marker that may be able to identify which patients are more likely to have these complications.
Emotional stress is known to trigger or worsen physical symptoms of disease, including some types of pain. A group of researchers from California found that stress and the anticipation of pain causes blood vessels to become narrower (vasoconstriction). In people with SCD, vasoconstriction can be dangerous because abnormally shaped (sickled) cells may be more likely to get stuck in the blood vessels and block blood flow.
A healthy digestive system is typically filled with various types of bacteria that aid in digestion. However, researchers from Howard University found that people with SCD are more likely to have higher levels of one specific bacterium, Veillonella. Veillonella link together to form a film in the digestive tract, which can attract red blood cells. When red blood cells stick to the film, it can block blood flow to the rest of the body, which causes increased pain. This discovery may help scientists find a way to rebalance gut bacteria levels and reduce symptoms.
These studies are just a few examples of the high-caliber SCD research being done. Read more highlights from this year’s conference:
Alzheimer’s drugs may improve red blood cell function and quality of life
Scientists explore ways to create red blood cells outside the body and prevent sickling
– Erica Roth
The market for electronic cigarettes (e-cigs) and vaping has surged in popularity within the past five years, while traditional cigarette sales have declined. From 2012 to 2013, e-cig sales more than doubled to $1.7 billion. By 2015, sales were estimated at $3.7 billion.
Although manufacturers claim that e-cigs are safer than traditional cigarettes, their use has been associated with clear health risks. E-cigs may seem like they are producing harmless water vapor, but that vapor has been shown to contain a mix of cancer-causing chemicals. Some of the toxin levels are comparable to those in cigarettes.
E-cigs are associated with cellular damage and decreased cough reflex sensitivity after just one use. Cough reflex—triggered by chemical or mechanical irritants—protects the upper respiratory system from infection by getting rid of respiratory secretions (mucus) and foreign material from the lungs. Decreased cough reflex sensitivity may increase the risk of infection because mucus and foreign material aren’t always cleared immediately from the airways. Studies on animals have found that nicotine-containing e-cig fluid may cause changes in the lungs similar to what humans experience with chronic obstructive pulmonary disease (COPD). COPD is a condition often seen in long-term smokers. These changes include narrowing of the airways, more mucus production and increased inflammation. E-cig vapor has also been linked to substantial DNA damage and increased cancer risk and decreased lung function.
More and more research is providing evidence that e-cigs pose serious health risks. One of the greatest concerns is the potential serious long-term consequences in teenagers. Teens are easy targets for tobacco and e-cig advertisers and may also be easily swayed into becoming lifelong tobacco users. Because of the potential health risks of e-cigs, the American Academy of Pediatrics recommends raising the legal purchasing age for both traditional cigarettes and e-cigs from 18 to 21. Marketing strategies of e-cigs try to make e-cigs look socially acceptable to young adults and teens by promoting candy-inspired flavors and vapor tricks on social media. The tendency for the e-cig market to prey on young adult consumers is particularly troubling because the brain is developing critical circuitry that relates to lifelong habits during this time. Users younger than 21 tend to remain nicotine users for life.
The Great American Smokeout sponsored by the American Cancer Society, is November 16. This event is designed to help smokers make a plan to quit, whether it’s traditional tobacco products or e-cigs. Their health depends on it.
Leigh Graziano, MS, is a second-year medical student at the Alabama College of Osteopathic Medicine. She works with Audrey Vasauskas, PhD, on research on pulmonary arterial hypertension, which is high blood pressure in your lungs. In her free time, Leigh enjoys yoga, mountain biking and fishing.
In the U.S., we focus much attention on the health behaviors that can help us live a longer life: the “secrets” of centenarians and long-lived animal species such as the naked mole rat, the optimal amount of exercise to help us maintain muscle tone and independence, and the best eating style—whether it’s eating like we live in the Mediterranean, restricting calories or something in between. Yet part of the U.S. population seems to be unlocking the keys to increased longevity despite having risk factors traditionally linked to a shorter lifespan.
Approximately 55 million people in the U.S. are of Hispanic descent, and on average, they live two years longer than non-Hispanic whites. The Hispanic population in the U.S. has a lower overall risk of dying from 7 of the top 10 leading causes of death, including cancer and heart disease. Known as the “Hispanic paradox,” these positive health outcomes are often achieved among immigrant populations and in people with a greater likelihood living in poverty, having less education and health insurance, being overweight and several other factors that can negatively affect health. Additionally, rates of illness and death from other chronic conditions such as diabetes and liver disease remain higher among Hispanics than whites.
In an effort to boost longevity across ethnicities, scientists are studying how these unlikely circumstances—being high risk in certain areas, yet having a longer lifespan—can coexist. Theories include:
- A study of lung disease in Hispanics suggests that their genes may protect against chronic obstructive pulmonary disease (COPD), an inflammatory lung disease, in addition to other factors.
- Hispanics who come to live in the U.S. are generally younger than the average population and stay healthier.
- With the exception of people from Puerto Rico, immigrants from Hispanic cultures smoke less than the overall population, leading to less lung disease. One study found that Hispanics in New Mexico are diagnosed less often with COPD than those living in other areas. Puerto Ricans, however, tend to smoke more and have a higher asthma risk.
- A diet rich in beans and lentils, common in some Hispanic cultures, may curb inflammation to reduce chronic health risks.
- Researchers think the strong family ties and support system seen in extended Hispanic families may play a role in staying healthy, particularly in the area of mental health.
Researchers continue to study Hispanic populations in the U.S. to try to find concrete reasons behind the Hispanic paradox to help them live even longer, healthier lives. During National Hispanic Heritage Month, we celebrate Hispanic heritage and culture in the U.S.—and all that these communities can teach us about living a healthier and longer life!
– Erica Roth and Stacy Brooks
Early humans were probably jacks of all trades when it came to food—they ate what was available, and the amount of carbohydrates, proteins and fats in their diet varied dramatically depending on where they lived. Except for honey, there were likely no sweeteners to “spice” up their meals. That all changed 200 years ago when table sugar—a combination of the sugar molecules glucose and fructose—began to be manufactured. This provided a steady supply of inexpensive sweeteners to the general population. From that time on, the amount of sweeteners humans ate began to rise drastically. It’s no coincidence that obesity and diabetes rates increased a few decades later. The cost of sweeteners were further reduced (and the availability increased) with the introduction of high-fructose corn syrup (HFCS) 40 years ago. HFCS is a processed form of glucose that can be easily added to many beverages and foods.
High sugar intake may cause physiological changes in the body that can interfere with the way organs are supposed to function and the way the body burns energy (metabolism) attained through food. The average non-obese person has a very low blood fructose concentration that may be as much as 100 times lower than blood glucose levels. Consuming fructose-laden desserts and sodas quickly increases blood fructose levels, flooding liver cells that are not used to such high doses. Fructose is rapidly broken down into easily processed substances (metabolites) that can be building blocks for fats.
Consuming a lot of fructose often leads to a marked increase in fat-forming enzymes and fatty deposits in the liver. Coincidentally, a decade after HFCS was widely introduced, a new metabolic disease—nonalcoholic fatty liver disease (NAFLD)—cropped up. NAFLD has been linked to overconsumption of fructose and added sugars. A fatty liver is associated with high triglycerides and “bad” cholesterol, increasing the risk for cardiovascular disease and obesity.
The good news is that these associations between added sweeteners, particularly fructose, and metabolic diseases have resulted in serious efforts to reduce consumption, like Mexico’s tax on sugary drinks and New York City’s (unsuccessful) attempt to ban sales of large sodas. In light of these efforts, people in the U.S. now seem to be eating less added sugars.
It is important to remember that moderate consumption of added fructose is most likely fine for most people. Fructose is the sweetest of the naturally occurring sugars and a little goes a long way. This is one case where “less is more.”
Ronaldo Ferraris, PhD, is a professor of pharmacology, physiology & neuroscience at the New Jersey Medical School at Rutgers University. He studies intestinal epithelial biology and cell differentiation as well as integrative regulatory processes involving sugar sensing, transport and metabolism in the small intestine.
After a healthy childhood, my best friend suddenly started having breathing difficulties when she was 20 years old. The doctor diagnosed her with asthma. With the help of inhaled medications, she was able to control her symptoms. But a year later, the medications were no longer effective and she started having monthly, life-threatening asthma attacks. The severe attacks became more frequent a few days before her menstrual period, and the symptoms disappeared days after her period ended. At that time, I wondered if hormones could be to blame.
As a graduate student investigating the role of male and female hormones in lung inflammation, I know now that asthma can be a hormone-related health issue. Unfortunately, many people are unaware of this relationship. Hormones are chemicals that travel as messengers around the body through the bloodstream. They affect many bodily functions and play a large role in a woman’s life cycle from birth through puberty, adulthood, pregnancy and menopause. In proper balance, hormones help the body communicate and thrive. But sometimes hormone levels can be too high or too low, causing serious health problems, especially in people with asthma.
Although more young boys have asthma than girls, the pattern is reversed in adults: More women have asthma than men. During puberty girls begin to produce higher levels of the sex hormones estrogen and progesterone, which rise and fall throughout their menstrual cycle. About one-third of females with asthma report premenstrual-related asthma symptoms, which may lead to severe attacks. A research study of girls ages 8 to 17 found that those who started menstruating at earlier ages developed more severe asthma after puberty, perhaps because their hormone levels began to change earlier in life. Studies have shown that hormonal changes can disturb the airways and inflammatory responses in the lungs. As hormone levels go up and down, new blood vessels in the lungs form and disappear, affecting the lungs’ ability to take in oxygen. In addition, female hormones do not just cause breathing problems in women with asthma, but also in those who smoke or are overweight.
Researchers are working to discover how sex hormones affect the lungs in order to develop personalized treatments for asthma. Ideally, specialized treatments in the future will be gender-specific and take into consideration a person’s hormonal status.
Nathalie Fuentes is a PhD candidate in the biomedical sciences program at Penn State College of Medicine. Her studies in Dr. Patricia Silveyra’s lab include the development of sex-specific therapies to treat lung diseases, sex differences in asthma-related lung inflammation triggered by ground-level ozone and the role of male and female sex hormones in lung disease. Nathalie is originally from Caguas, Puerto Rico.
What makes your father the best dad in the world? Maybe it’s his sense of humor or the times he has taken you to the movies or played catch in the yard. Or maybe it’s the fact that he made healthy lifestyle choices before you were born. Recent research suggests that your father’s health before you were conceived (preconception) may change the way your genes behave to affect your future health. It almost sounds like something out of a science fiction movie, but it’s real.
Studies tend to focus on the mother’s preconception health and the risks her baby might face later in life if she’s overweight. But a dad’s weight and early eating habits can also play a role, according to research published in the American Journal of Stem Cells. Researchers found that offspring of men who were obese before reproducing were more likely to have diabetes and be overweight. On the other hand, the researchers also found that fathers who had limited food resources in their early life caused genetic changes that protected their children—and even grandchildren—against cardiovascular disease.
Most people know that exercise is one of the healthiest lifestyle choices you can make to maintain your weight and keep your heart and even your brain healthy. However, research presented at the APS Integrative Biology of Exercise 7 meeting showed that offspring of men who exercised long term before conceiving had a higher likelihood of being obese and developing diabetes. This result was a huge surprise to the research team, but is it a reason to stop exercising? Not really. The study focused on how efficiently the body used energy on a high-fat diet. Limiting dietary fat and being active is still the way to go for most people.
Keeping stress levels low is also a good plan for dads-to-be. One study suggests that a man’s preconception stress may program his kids for mood disorders. Researchers found a pathway in the brain that transmits signals about stress hormones, and it may be passed down to the next generation. If the signal is passed on to you, then your father’s stress levels could affect your predisposition for anxiety and depression.
These studies represent clues to learning how genetic material is transformed as it passes through generations. It’s also a reminder that following a healthy diet, staying active and maintaining mental health is important for everyone at every age.
Happy Father’s Day!
– Erica Roth