“I’m not flexible enough to do yoga!” In my 12 years as a yoga instructor, this is the excuse I have heard most often for why people aren’t practicing yoga. My initial response is usually, “That’s exactly why you should be practicing yoga!” However, I am also an assistant professor of physiology, and I know that the benefits of yoga go far beyond flexibility. Participating in yoga regularly imparts a number of benefits— from weight management to stress reduction—to our physical and mental health.
One very important side benefit of yoga that is linked to both physical and mental health is breath control. Slow, deep, conscious abdominal (belly) breathing, especially during difficult poses, trains us to use the same type of breathing in challenging scenarios off the mat, such as giving a presentation, taking an exam or performing a difficult task.
Why do deep, yogic belly breaths help us through stressful situations? Recent studies suggest that this type of breathing can decrease firing of the sympathetic nervous system while increasing activity of the parasympathetic nervous system. The spike in heart rate and blood pressure, sweaty palms and voice tremors you might experience when you speak in front of an audience, for example, are due to activation of your sympathetic nervous system—the “fight-or-flight” response. This nervous response is great if you are running from a bear in the woods. But in real life these changes can lead to short-term memory problems and high anxiety levels that may interfere with giving a presentation or taking a test.
If you approach stressful situations with abdominal breaths, however, you help shut down the fight-or-flight reaction and increase the parasympathetic nervous response. Called a relaxation response, your heart rate slows down and your blood pressure returns to normal. Once you’re relaxed, you can approach the task at hand in a calm, collected way.
Many types of yoga incorporate physical movements with deep abdominal breathing. The physical demands of these movements have the potential to cause the fight-or-flight response, but by combining these poses with yogic breathing, we learn how to control our breath in seemingly stressful situations. So the next time someone tells me they are not flexible enough to do yoga I will ask them if they can take a deep breath. If they say yes, then I know they are ready to go!
September is National Yoga Month. Check out a yoga class or festival near you.
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
Although walnuts are recommended as an effective way to control appetite in people with diabetes, just how they regulate appetite has only recently been discovered. In a new study published in the journal Diabetes, Obesity and Metabolism, researchers examined the brains of 10 obese volunteers who drank breakfast smoothies for five days. Some of the volunteers drank smoothies containing walnuts, while others drank nut-free smoothies that looked and tasted identical. One month later, the participants repeated the study, but this time those who received walnut smoothies during the first trial drank the nut-free beverage and vice versa. Neither the volunteers nor the researchers knew which smoothie the participants consumed during each phase of the study.
At the end of each five-day trial, the volunteers—on an empty stomach—looked at images of “desirable” high-fat foods such as cake and onion rings, healthy foods like fruits and vegetables, and non-edible things like rocks or trees. The people who consumed the walnut smoothies consistently showed more activity in the area of the brain associated with regulating the behavior of eating and feeling satisfied (satiety) when they looked at the high-fat foods. By stimulating this area of the brain called the insula, the researchers think that walnuts promote weight loss by reducing cravings. In fact, the study participants reported feeling less hunger and feeling like they could eat less food after their walnut trial as compared to their nut-free trial.
In addition to reducing food cravings, walnuts are low in saturated fats and high in omega-3 fatty acids and are good sources of fiber and protein. The next time you have the urge to snack, grab a handful of walnuts.
Karen Sweazea, PhD, is an associate professor in the School of Nutrition & Health Promotion and the School of Life Sciences at Arizona State University.
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.