I've received quite a few emails asking me about natural ways to boost one's immune system. Most of these questions came as a result of the current Swine Flu outbreak, which continues to progress worldwide. A lot of the information out there about Swine Flu is alarmist and meant to frighten people. I think it's much more useful to be vigilant about our personal well-being than to be scared about it, so I've been giving people some practical advice that can be applied year round.
Illnesses like the common cold and the flu typically enter our bodies through the respiratory tract, so the first step to staying healthy is protecting the respiratory system. If the mucus membranes in the nose and throat stay strong and intact, the immune system won't have to be tested by these viruses. You've heard it a million times before, but regularly washing your hands is the best way to keep active viruses away from your respiratory system. Wash with warm water and hand soap for at least 10 seconds before you eat, after you get off the subway, when you get home from work, and before going to bed. Avoid antibacterial soaps: they don't protect you against viruses and they can dry out the skin on your hands, making them more hospitable to some viruses.
Start making a habit of gargling regularly with warm saltwater. This remedy has been used for ages to treat sore throats, but a saltwater gargle will also keep your mouth and throat clean and will reduce any inflammation caused by viruses that have found their way into your system. A NOTE OF WARNING: if you have hypertension you should NOT gargle with saltwater.
There are several foods you can add to your diet that either have known antiviral or immunity boosting effects. Garlic does both. Your best bet is to consume a clove of raw garlic a day, but if that isn't practical you will still benefit greatly from eating cooked garlic in your food. Other immunity-boosting foods include mushrooms (especially shitake), carrots, sweet potatoes, and beef. Mushrooms are a superfood, full of many of the vitamins and minerals our bodies run on, while carrots and sweet potatoes are rich in Vitamin A. Vitamin A protects mucus membranes and works best when eaten in vegetable from instead of as a supplement. Beef is an excellent source of the mineral zinc, which plays an integral role in immune function. Oysters are another great source of zinc.
You also want to increase your vitamin C intake by eating more citrus, strawberries, pineapple, and potatoes. Leafy green vegetables can be a good source of vitamin C when eaten raw, but don't make an entire meal out of raw vegetables.
Finally, stay away from sugar! Viruses and bacteria love a sugar-loaded organism, so please avoid refined sugar if you feel the least bit sick.
The best way to get your vitamins and minerals is through the foods you eat, but occasionally it's necessary to take a supplement when you know your immune system is more vulnerable. Multivitamins are a good first line of defense since they contain most of the vitamins and minerals needed to keep you healthy. You'll certainly get enough Vitamin A (in addition to the foods you eat) from a multivitamin. Vegetarians and people who get sick easily would benefit from taking an extra 30mg of zinc every day, in addition to taking a multivitamin. During cold and flu season, everyone would benefit from taking an extra 1000mg of vitamin C each day.
Perhaps the most important supplement you can take to boost your immune system is vitamin D. In the past few years there have been several studies on the effects of vitamin D in combating influenza, with some researchers suggesting that the flu is an opportunistic virus that only afflicts people with vitamin D deficiencies. Few multivitamins contain enough vitamin D to keep you healthy, and it is difficult to get an adequate amount of vitamin D from dietary sources alone. The best source of vitamin D is the sun, but unless you live in the tropics or you work outdoors all day you are probably not getting your daily dose of sunshine. Take 2000 IUs of Vitamin D-3 each day to supplement your diet and sun exposure.
There are also some single-herb supplements that you may want to consider taking, including reishi mushrooms, echinacea, goldenseal, and royal jelly. There is a ton of literature available on each of these supplements and I can answer questions about them if anyone is looking for more information.
Check out http://www.iherb.com/ for some trustworthy brands for vitamins, minerals, and other supplements.
During the SARS outbreak in 2003, people in Hong Kong, Taiwan, and Mainland China were treated in both biomedical hospitals and TCM (Traditional Chinese Medicine) hospitals. In April of that year the Associated Press began to report that the TCM hospitals were seeing some positive results using herbs, while biomedical hospitals had spotty results using antiviral medications that were developed to treat the flu and certain forms of hepatitis. Buoyed by these results, biomedical hospitals in Hong Kong began to administer Chinese herbs, a practice they had abandoned in the 1940s. Meanwhile the general population began taking these same herbs prophylactically. By the end of May the number of new cases per week dropped by two-thirds and the outbreak was well on its way to being contained.
The following World Health Organization clinical study published in 2004 confirmed a lot of the anecdotal evidence that was seen in these hospitals: http://www.who.int/medicinedocs/en/d/Js6170e/13.html
I'm certainly not prepared to say that the use of herbal medicine stopped the outbreak of SARS. Many elderly and immune-deficient people still died from the disease after taking Chinese herbs, and people began to respond well to antiviral medication once medical authorities refined their approach. The U.S., for example, reported no known deaths from SARS. But I strongly believe that many of these herbal remedies strengthened the immune systems of people who were not yet affected by SARS, which left the virus with fewer and fewer hosts from which to spread. The point here is that a population with a strong collective immunity was able to effectively protect itself from a spreading epidemic.
Herbal medicine is a tricky science and I don't recommend you go out and buy Chinese herbs because you read a specific formula is good at boosting the immune system. I also don't recommend taking single-herb supplements like Astragalus, Andrograhis, and Isatidis. These Chinese herbs have proven immunity-boosting and antiviral properties, but they are most effective when they are taken as an ingredient in an herbal formula. Chinese herbal formulas contain more than one active ingredient, so it's important that you know what you're taking and that it's been recommended by someone who was a background in herbal medicine. If you're interested in taking Chinese herbs, write or call me and we can discuss what I think would be best for you.