Table of contents for Shape Immunity in Shape Immunity

The immune system, one of the many marvels of the human body, is sprawling, vigilant, and on the clock 24-7. It includes bone marrow, which produces immune cells; lymph nodes to filter out viruses; and the spleen, which detects damaged red blood cells and some of the blood’s unwelcome microorganisms. The system has cells that engulf and eat bacteria, and others that destroy those infected by a virus. This far-flung network even has its own checks and balances, to make sure that its responses are proportionate. How your immune system responds to a virus or other invader comes down to some luck of the draw; its abilities are based on a mix of genetics, age, sex, environment, and infection history. Yet that doesn’t mean you don’t have any control over…

The benefits of exercise are well documented: It reduces the risks of developing certain ailments such as heart disease, it helps keep weight under control, and it even has proven links to mental well-being and brain health. Research over the past few decades has found that regular workouts can help sharpen the body’s defenses and strengthen the immune system. “The immune system actually needs exercise to do its job properly,” says David Nieman, DPH, a professor of biology at Appalachian State University and the director of the Human Performance Lab in Kannapolis, North Carolina. He compares the body to the military, with the immune cells functioning like a special class of soldiers. When the body is at rest, the immune-cell foot soldiers are able to handle their considerable duties just…

You likely already know the signs of a cold—runny nose, congestion, sneezing, cough—but how do you know it’s just a run-of-the-mill illness and not something more serious? Here, doctors explain how to tell if you have the common cold or a condition that requires a little more medical attention, such as the flu, strep throat, or mononucleosis. YOU’VE HAD SYMPTOMS FOR LONGER THAN FOUR DAYS The common cold tends to clear up on its own in three to four days, says Melisa Lai-Becker, M.D., site chief of emergency medicine at Cambridge Health Alliance. It starts with a scratchy throat, congestion, and runny nose, and then a cough usually develops. While your cough and postnasal drip may linger, most head cold symptoms should disappear after four days. “With a cold, you…

Ever wish you could tell that cold to just chill out? The average American is afflicted with two or three colds per year, according to the Centers for Disease Control and Prevention (CDC). While they’re frustratingly common—and contagious—colds are a bit like snowflakes. No two are the same. “There are no official stages of a cold. Each is individual and follows its own path. Some last for hours, others for days or even weeks,” says Adam Splaver, M.D., a cardiologist in Hollywood, Florida. But there are some general trends in cold symptoms, timelines, and treatment methods. From “How long does a cold last?” to “How do I feel better faster?” we spoke to medical experts for a complete guide to (fighting back against) the common cold. HOW DO I CATCH…

Inflammation is one of the hottest health topics of the year. But until now, the focus has been solely on the damage it causes. As it turns out, that’s not the whole story. Researchers have recently discovered that inflammation can actually make us healthier. It has powerful healing effects and is a critical component of the immune system, says Joanne Donoghue, Ph.D., an exercise physiologist at the New York Institute of Technology College of Osteopathic Medicine. You need it to generate muscle, heal from injuries, and even power through a tough day. The way it works is this: “Whenever you strength-train or do cardiovascular exercise, you’re creating minitraumas in your muscles,” Donoghue explains. That triggers inflammation, which prompts the release of chemicals and hormones to repair the affected tissue and…

There are a lot of questions about vitamins these days. We used to think of them as another good way to stay healthy, along with exercise and eating right. But then a couple of years ago, some research found that supplements might not help reduce our risk of disease after all. And most of us were left wondering whether to take our vitamins or toss them. Well after experts took a closer look, we have some answers. You shouldn’t give up on vitamins completely, they say, but you do need to be smart about which ones you take. “There are a lot of worthless supplements out there, but there are many really good ones too,” notes Mark Moyad, M.D., the director of preventive and alternative medicine at the University of…

During cold and flu season, or in the midst of a global health crisis, we’re all a little sensitive when someone sneezes near (or on) us in line at the grocery store. So how can you keep yourself safe from others’ germs? There are ways to stack the odds in your favor: Get your flu shot, eat nutritious foods, wash your hands, get lots of sleep—and do yoga! Yes, yoga. Each of the following poses can be helpful in warding off the flu and colds, as well as managing the symptoms should you fall prey. They take only a few minutes, so try to do them right before bed three times a week, or every day if you feel something coming on. Not only will you reap the protective benefits…

You know the ways that stress wreaks havoc on your body: Your muscles tighten, your energy levels drop, and your blood pressure shoots up. But ringing in your ears? Running to the bathroom? These could be signs you just need to calm down too. Here, 10 of the weirdest ways that cortisol messes with your body. YOUR BRAIN SHORT-CIRCUITS High stress situations—you know, like that work presentation tomorrow—can trigger the release of adrenaline and other fight-or-flight hormones. While those chemicals heighten your brain’s alertness and threat-detection centers (which can be good), they temporarily kneecap your noodle’s cortical networks, which are responsible for contemplation, critical thinking, and planning, explains Erno Hermans, Ph.D., of Radboud University in the Netherlands. That happens because your body is conserving energy for a physical confrontation (which,…

Marcy* is a vice president at a Fortune 500 company and a mom of two school-age children. She is an active volunteer in her community and in others—she flew to Houston for a week to help rebuild after a hurricane. She is also a world traveler, a leader at her church, a gardener, a runner, and a hot-yoga enthusiast. Oh, and she hasn’t taken a single sick day since 2007. It isn’t that Marcy never gets sick. She just never gets sick enough. “We are given a bucket of PTO [personal time off] days, and whether you use them for vacation or staying home sick, the company doesn’t care,” the executive explains. “I’m not going to waste them sitting at home nursing a cold. To me, PTO days are for…

When you’ve got the flu, the only true cure is rest and time—there’s no food or drink that will magically make your symptoms go away. But making sure you’re staying hydrated and eating nutrient-rich foods can help ensure you don’t feel any worse than you already do and may help ease your discomfort and get you back on your feet faster. Because you may not feel like eating much at all when you’re under the weather, we asked two nutritionists about foods and beverages that go down easy and pack the biggest immunity boosting, symptom-soothing benefits. Here’s what they recommend—based on research and their own experiences—adding to your sick-day routine. ELECTROLYTE BEVERAGES “Staying hydrated is the most important thing when you have the flu, especially if you’re running a fever…

During cold and flu season, and especially in the midst of a global health crisis, keeping the immune system working at its best to stave off illness and infections has never been more important. For many of us this means seriously upping our handwashing game, packing sanitizer everywhere, keeping a reasonable distance, and side-eyeing anyone in public with a cough. (For the love of Nyquil, cough into your elbow!) But research is pointing to a new weapon in the cold-fighting arsenal—and it’s no further than the bedroom. Preventing the common cold may be as simple as getting enough sleep, says a study published in the journal Sleep. Researchers asked 164 healthy adults to wear a small device that monitors sleep-wake cycles for a week. They then shot a live cold…

GREAT GREENS ELIXIR Start your morning on a nutrition high note with this drink sweetened with apples. 2 cored and chopped apples1 cup baby spinach leaves1 cup roughly torn romaine2 cups filtered water (or unsweetened coconut water)1½ cups chopped cucumber⅓ cup chopped celery⅓ cup flat-leaf parsleyJuice from 1 lemon 1. Blend all ingredients. 2. After blending, pour through a fine-mesh sieve or cheesecloth, pressing on solids to get all juices out. (Freeze the pulp in an ice cube tray to use in a vegetable soup base.) TROPICAL GOLDEN SMOOTHIE Pineapple and mango, with protein-rich kefir and a hint of coconut, make this a refreshing way to keep hunger at bay between meals. 1½ cups frozen pineapple chunks½ cup frozen mango chunks1½ cups plain kefir½ cup unsweetened coconut water1 tablespoon chia…

In the months that Melody Lehrman, a contract recruiter in Stratford, Connecticut, has been home full-time because of Covid-19, her health behaviors have changed dramatically. Hour-long walks with her dog have fallen by the wayside, and she has often been up past midnight, snacking and checking her phone. On the plus side, Lehrman, 43, has also kept some healthy habits, including sneaking veggies into family meals (one trick: she mixes chopped kale or spinach into meatballs and burgers). She has also been spending more time outside with her 9-year-old daughter, Amber, to keep their bodies moving, and in the spring bought a paddleboard and kayak for family outings. When Lehrman attended a small in-person yoga class and it made her feel better mentally and physically, she vowed to keep it…

Scientists, after extensive studies, are finally beginning to fully understand the effect that light has on our internal systems. “The light receptors in our eyes communicate directly with the brain, synchronizing the circadian clocks that affect our immunity, appetite, mood, energy, and even pain tolerance,” says Charles Czeisler, M.D., Ph.D., the chief of the Division of Sleep and Circadian Disorders at Brigham and Women’s Hospital. Exposing yourself to the right rays at the right time has a huge impact on every aspect of your health. THE LIGHT-BRAIN CONNECTION When light enters your eyes, it’s transmitted directly to a small cluster of brain cells in your hypothalamus, called the suprachiasmatic nucleus (SCN). Your SCN is your body’s master clock, says Dan Pardi, Ph.D., a former researcher in the departments of neurology…

In March 2018, I went to the emergency room with an upset stomach. For days, I’d been experiencing constant abdominal aches—an annoying cycle of pain that I couldn’t seem to shake. I decided it had to be appendicitis. Something small, something manageable. I’d be back to work the next day, taking calls, going on runs, meeting my friends for dinner. I was so very wrong. Hours later and entirely alone, I was told the news that would change my life forever: I had cancer. It was everywhere. And I was terrified. Next I had to make the tough phone call to my parents: “Mom, Dad, I’m calling you from the hospital. Also, I have cancer.” GETTING DIAGNOSED Three days later—and now with my parents by my side—I finally got an…

If you find yourself reaching for a packet of Emergen-C every time you feel a tickle in your throat, you’re certainly not alone. The fizzy orange powder—a mix of vitamins C and B, along with other nutrients—has become a mainstay of medicine cabinets, winter-weather survival kits, travel packing lists, and even wedding weekend goodie bags. “A lot of patients ask me about these products, and many of them can be very adamant about how certain they are that it helps them,” William Curry, M.D., a professor of internal medicine at the University of Alabama at Birmingham, told Health magazine in 2018. Because Emergen-C is a supplement, it can’t make specific health claims. (In fact, its manufacturer settled a lawsuit in 2014 after it was accused of doing just that, without…