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As the weather cools and the kids settle back into school, you may find yourself worrying that you and your family will become victims of cold and flu season. The good news is that you don’t need to let a runny nose or sore throat put you on the sidelines. The 30 tips—plus one bonus idea—found here can boost your immunity and decrease your odds of getting sick. You’ll also learn lots of ways to speed your recovery if you do end up feeling under the weather.
Taking a proactive approach to immunity doesn’t just pay dividends during cold and flu season. Creating and maintaining a strong immune system this month also protects against viral, fungal, and bacterial invaders 365 days a year.
Eating for Strong Immunity
1. Snack smarter by focusing on healthy foods
Research shows that regularly munching on nutrient-dense foods can help enhance immune function and may even contribute to a longer life, while less healthy fare can compromise your defenses. Just try a few of the following options:
2. Focus on fats
Specifically monounsaturated and omega-3 fats, both of which help to tame systemic inflammation and free your immune system to defend against pathogens. Scientists have known for some time that diets high in unhealthy fats impair immunity by decreasing the function of T-cells. What’s more, good-for-you fats help your body absorb fat-soluble nutrients such as vitamins A, D, and E.
Enjoy more almonds, avocados, and olive oil (rich in monounsaturated fats), as well as salmon, halibut, sardines, and other cold-water fish (high in omega-3 fats). In general, healthy fats should make up roughly 30 percent of your daily caloric intake.
3. Add a side of leafy greens
Research in the journal Nature Immunology shows that leafy greens (e.g., spinach, collard greens, and Swiss chard) help the body produce innate lymphoid cells (ILCs), digestive immune cells that play an important role in protecting the body from infection.
4. Make sure that you’re getting enough protein
The amino acids in protein form the building blocks of all the body’s cells, including your immune cells. If you don’t eat enough protein, you’ll manufacture fewer white blood cells to combat antigens. How much is enough? The general rule of thumb is to consume 0.8-1 gram of protein per kilogram (kg) of body weight.
5. Think oats for your heart — and your immune system
The fiber in oats activates NK cells, thanks to their high beta-glucan content. Oats are also a great source of vitamin E and B vitamins. Steel-cut oats boast twice the beta-glucan as rolled oats.
6. Eat more shiitake mushrooms
Beta-glucans in shiitakes help guard against everyday ailments, but the mushrooms have also shown an impressive ability to improve human immunity, according to research published in the Journal of the American College of Nutrition.
7. Enjoy Brazil nuts
These high-fat, satisfying nuts are one of the best food sources of selenium, a mineral that plays a key role in immune health, including flu prevention and reduced cancer risk. They are best stored in the fridge.
8. Start juicing
Carly de Castro, one of the founders of the Los Angeles-based chain Pressed, transformed her health simply by adding a green juice to her daily regimen. De Castro, along with Hedi Gores and Hayden Slater, shares her full story, juicing tips, and collection of recipes in Juice.
9. Consider going Paleo
“Humans should mimic the diet followed by people during the Paleolithic era,” says Mariel Lewis, in her book Paleo Smoothies. “During this time the human diet focused on eating high-protein foods (a low-glycemic diet), fruits and vegetables (containing healthy phytochemicals, vitamins, and minerals, which tend to promote proper immunity and make you healthier), and long-chain omega-3 fatty acids (which calm down inflammation).”
10. Have a cuppa the leafy stuff
In a Harvard study, people who drank 5 cups of black tea per day for two weeks had 10 times more virus-fighting interferon in the blood than others who drank a placebo hot beverage.
11. Use 100% whey protein powder
Whey protein can help fight off colds and flu because it boasts beta-glucans and immunoglobulins — two building blocks that protect your immune system. Try: Bluebonnet Nutrition Whey Protein Isolate Powder.
12. Feast on pomegranate
The seeds and the juice contain high levels of antioxidant compounds that have been shown to deter the growth of certain cancer cells. The juice, in particular, provides the most concentrated source of antioxidants.
13. Bolster immune-boosting bacteria in your gut
Fermented foods such as kefir, sauerkraut, and kimchi provide good gut bugs that can help reduce gastrointestinal woes, stave off respiratory infections, and enhance immunity, according to research.
14. Season fish and poultry dishes with citrus zest
Citrus boasts antimicrobial properties and adds a nutritional punch of vitamin C and flavonoids with anti-inflammatory capabilities.
15. Drink up!
Staying hydrated helps immune cells function properly. Opt for half your body weight in ounces of pure water every day.
16. Sip some soup, especially chicken soup, if you’re sick
It’s not just an old wives’ tale: A study in the journal Chest shows that even store-bought chicken soup helps block inflammatory cells and thin mucus.
Simple Immune-Optimizing Habits
17. Tune in to some soothing tunes
Research shows that listening to “environmental music” for just 30 minutes increases the immune system’s production of illness-fighting immunoglobulin A (IgA).
18. Sleep well
During a trial at the University of North Texas, students who suffered from insomnia produced fewer antibodies after receiving a seasonal flu shot. If you’re having trouble getting enough zzzs, try melatonin — it’s a powerful antioxidant that helps enhance the response of the immune system’s T-helper cells and also regulates inflammation.
19. Avoid smoky environments, whenever possible
Not only does tobacco smoke trigger inflammation, but it also raises the risk of upper respiratory infections.
20. Take a walk
Simply starting your day with a brisk, 30-minute walk can get you energized and jump-start your immunity.
21. Make your own household sanitizer
Mix 8 oz. of water and 30 drops of rosemary or tea tree essential oil. Pour in a spray bottle and use on doorknobs, phones, cutting boards, or any place viruses are likely to linger.
Stock a “Stay-Well” Medicine Cabinet
Derived from the wood of larch trees, larch arabinogalactan (larch for short) is a natural source of dietary fiber, but studies have found that it also possesses powerful therapeutic benefits for immunity, and is a proven ally against the common cold. It has also been shown to enhance the effectiveness of several vaccines, including those for tetanus and pneumonia.
Created via a proprietary fermentation process, EpiCor transforms baker’s yeast into a complex ingredient comprising dozens of compounds and metabolites that work together to strengthen immunity. A 12-week randomized, double-blind trial of 116 people who hadn’t gotten a flu vaccine found that a daily dose of EpiCor reduced their number of colds or cases of the flu. And if they did happen to get sick, they weren’t under the weather for as long as those taking a placebo.
24. Medicinal mushrooms (maitake, reishi, and cordyceps)
Research shows that these fungal superstars are rich sources of lentinan, which helps fight infection, and beta-glucan. Maitake D-Fraction (made by Mushroom Wisdom) has been clinically shown to help stimulate cancer-fighting immune cells.
25. Immune-boosting herbs (garlic, oregano, olive leaf, elderberry, andrographis, and astragalus)
Pick one of the above or try a combination formula designed to support immune health. Each of these herbs has been shown in studies to support immune function in some way, including boosting the body’s resistance to illness; easing cold and flu symptoms; or speeding recovery from colds and flu.
Research suggests that taking probiotic supplements may greatly protect against a variety of pathogens, including staph bugs, E. coli, salmonella, and even the superbug Clostridium difficile. Researchers from the University of Florida reported that a trio of specific probiotic strains — Lactobacillus gasseri, Bifidobacterium bifidum, and Bifidobacterium longum — trigger a beneficial shift in the bacterial composition of the gut. This may enhance immunity, especially in older adults.
Made from an extract of duck heart and liver, this homeopathic remedy is said to work best when taken at the first sign of flu-like symptoms. Several double-blind studies have found that it effectively eases flu symptoms and shortens suffering.
28. Zinc and Vitamin C
According to a review of 13 studies, taking 75 mg of zinc each day can shorten the duration of the common cold by up to 42 percent. And when Israeli doctors gave vitamin C to a group of competitive swimmers with upper respiratory infections, 47 percent of those taking a daily dose of C experienced less severe symptoms and a more rapid recovery than those who didn’t supplement with the vitamin. Camu Camu, a small fruit found deep in the Amazonian rainforest, is one of the most concentrated plant-based sources of vitamin C, according to research in the Journal of Cardiology.
Found in protein-rich foods such as nuts, red meat, eggs, milk, cheese, beans, and sardines, this essential amino acid has been shown to help prevent and treat viral infections such as cold sores, shingles, human papilloma viral infection, and genital herpes.
Replete with high amounts of protein, fat-soluble vitamins and minerals, and transfer factors including immunoglobulin antibodies, supplemental bovine-derived colostrum has been shown to enhance selected immunity in adults.
31. Try the Sunshine Strategy
Studies suggest that boosting your immunity with vitamin D might help to ward off common cold-weather illness such as the flu. In fact, the active form of vitamin D appears to temper the damaging inflammatory response of some white blood cells, while also boosting immune cells’ production of microbe-fighting proteins. Dubbed the “sunshine vitamin,” D may also help you live longer. Researchers at the University of California, San Diego, have found that people with low levels of vitamin D were twice as likely to die prematurely compared to those with high blood levels of the fat-soluble vitamin. According to the authors of the study, daily doses of up to 4,000 IU are both safe and effective. If you are extremely low in the vitamin, you may need even higher doses-as much as 10,000 IU daily- for a period of time. Ask your doctor to check your blood levels of vitamin D with a simple blood test.
According to the Vitamin D Council, signs that suggest low vitamin D levels are tiredness, general aches and pains, weakness, pain in your bones, frequent infections, and difficulty getting around. People at the highest risk of a deficiency include those with darker skin; people who spend a lot of time indoors and/or cover their skin all of the time; older people, whose thinner skin may mean they can’t produce enough vitamin D; anyone who lives in the Northern part of the United States or in Canada; and people who are obese.