What can we do to stay healthy and fend off germs? This topic has been on all our minds lately. An American researcher explains how to keep our immune systems in tip-top shape, how nutrition can help with this, and tells us her eight top tips.
“Most people don’t think about their immunity until they get sick. Now we know how important it is to have a strong immune system,” says Penny Kris-Etherton, PhD, Distinguished Professor of Nutrition at Penn State University, and Immediate Past Chair of the Lifestyle Council for the American Heart Association. Dr. Kris-Etherton studies the role of nutrition in preventing disease. We sought her advice to help all of us better understand how the immune system works, and what you can do to keep yours in tip-top shape.
How your immune system works
Your immune system is your body’s natural defense against things that could make you sick. When you encounter something like a bacteria or virus, your immune system springs into action recognizing the harmful invaders, producing antibodies to target them and helping you heal should you get sick. A strong immune system can help prevent you from getting sick as often and can also help fight off illness more quickly and with less down time if you do get sick. We are born with some level of immunity (called innate immunity). Our bodies learn the rest over time, which is called adaptive or acquired immunity.
If your immune system is weakened, then your defenses just aren’t operating at their peak. This could be for any number of reasons. For example, our immune systems become less efficient as we age. “Because of this, older people are more susceptible to getting sick and have to be even more cautious, even if they do all the right things to stay healthy,” shares Dr. Kris-Etherton.
Your “immunity engine” maintenance plan
Our immune systems are extremely complicated and consist of different organs, cells, and proteins. This complicated machinery requires a well-balanced maintenance plan to keep it running at its best. But what does a maintenance plan consist of? You can support your immune system with a healthy diet, good hydration, and regular exercise. Maintaining a healthy weight, enough sleep, and good stress management also help your defenses. Drinking as little alcohol as possible and not smoking give your defenses a fighting chance, too.
While we can’t always control the germs we encounter out in the world, the good news is we can control these lifestyle factors. No matter your age, embracing healthier habits can directly pay off for immune health.
8 ways to strengthen your immunity
Okay, what specific things can you do? Avoiding germs and washing your hands regularly is always advisable. But it turns out that good hygiene is just the beginning. Dr. Kris-Etherton offers these eight tips to help keep your immunity engine humming along. Of course, there is no single magic bullet here, but the combination can make a real difference in maintaining a healthy immune system.
- Eat more fruits and veggies
“We know good nutrition aligns with good immune health,” says Dr. Kris-Etherton. Fruits and vegetables contain critical, immune-supporting nutrients. These include vitamins A and C, iron, selenium, and zinc. Dark green, red, yellow, and orange vegetables are sources of vitamin A. Red peppers, cabbage, and blackcurrants are super sources of vitamin C. Cruciferous vegetables like broccoli, cauliflower, and cabbage are also sources of selenium. Spinach and fennel are great sources of iron. Mushrooms and herbs are a good source of zinc. Aim to fill half your plate with fruits and vegetables. The more colorful and varied your diet, the better!
- Power with protein
Protein plays a role in helping your body heal and recover. Plant protein from pulses, grains or nuts and seeds can contribute here. Good sources of animal protein are lean meat, poultry, and eggs. But also remember that fish is an all-round health booster. “You especially want to try fish rich in healthy fats, like salmon, mackerel, and herring, which contain omega-3 fatty acids and vitamin D, both of which have beneficial effects on immune health,” Dr. Kris-Etherton advises. Aim for two or more servings of fish a week.
- Choose healthy hydration
As Dr. Kris-Etherton puts it: “The body needs fluids to function and to keep things going. Too little fluid quickly leads to poor performance. The goal is to drink at least 1.5 liters a day. Water is the best way to quench your thirst. But unsweetened coffee, tea, and other low-calorie beverages are also okay.
- Don’t rush to supplement
A varied diet usually provides your body with all the nutrients it needs. Plus, it’s more natural and tastes better. That’s why Dr. Kris-Etherton recommends mainly eating fresh food. Food supplements are only necessary in exceptional cases. For example, for at-risk groups, people with certain illnesses and people who need supplements to help fill nutritional gaps. When choosing supplements, always check with your health care provider or nutritionist.
- Break a sweat
The best way to keep your immune system up to speed is to exercise regularly. Regular exercise can help you achieve a healthy weight, improve your heart health, and lower your blood pressure – which all work to support a healthy immune system. “What’s more, regular moderate exercise can help reduce the length and severity of upper respiratory infections, like the common cold,” Dr. Kris-Etherton adds. Get at it! Shoot for at least 30 minutes of activity a day most days of the week.
- Get enough sleep
Strengthening your immune system while you sleep? Nothing could be easier. “There is growing evidence that poor sleep habits can increase your risk for poor heart health, which leads to poor health overall,” says Dr. Kris-Etherton. Most adults should get at least seven hours of shut-eye each night. It’s time well spent, as resting gives your body an opportunity to fight off any invaders. But not all sleep is created equal! Get high-quality sleep by keeping your bedroom dark and quiet and switching off your electronic devices.
- Stay on top of stress
What stresses you out also stresses out your immune system. “There is research showing that stress can affect immune function,” says Dr. Kris-Etherton. So good stress regulation pays off twice: for you and for your immune system. Make stress reduction a daily practice and find ways to relax. Even 15 minutes can work wonders!
- Steer clear of harmful habits
It’s great to establish healthy habits. But it’s even more important to avoid those that might hurt your immunity. If you smoke less or not at all, you’ll do your immune system a big favor. Eating too many processed foods, which tend to be high in added sugar, salt, and saturated fat won’t help your immune system at all. “Ultra-processed, high calorie foods are often lacking in nutrients and can promote disturbances in the gut such as inflammation, which has been associated with suppressed immunity,” Dr. Kris-Etherton explains. Avoiding too much alcohol is also important. If you choose to drink, you should have no more than one drink per day.
A domino effect
Implementing all eight of these tips is challenging. But you don’t have to tackle everything at once. Just start with a small change first. Often, one new habit fuels another. A healthy diet will help you sleep better, which gives you more energy for exercise or helps you manage stress, and so on. Exercise is another great place to start. Small, realistic steps are what lead to big, lasting changes. Before you know it, you’ll be well on your way! “Lead a healthy life as best you can,” says Dr. Kris-Etherton. “That’s the best thing you can do.”
Note: Since everyone’s health history and nutritional needs are so different, please make sure that you talk with your doctor and a registered dietitian to get advice about the diet and exercise plan that‘s right for you.