Five Foods to Support Your Immune System

by Andrea Zengion, ND, LAc

Fall is approaching, school has begun, and it’s time to think about preparing for cold and flu season. Without a doubt, the most important medicine we take each day is our food, and the following are some great choices to keep your immune system healthy.

1. Medicinal Mushrooms
Numerous types of mushrooms have been shown to gently stimulate immune function, especially when taken over long periods of time. While many mushrooms are good for you, a few are used medicinally specifically to boost the immune system. Three that stand out are shiitake, maitake and reishi mushrooms.

Many studies have shown that shiitake mushrooms effectively increase counts of certain types of immune cells, enabling the body to better fight infection. They are also antimicrobial, meaning that they can help to kill certain bacteria and viruses. Shiitake have a rich, earthy flavor and can be used in a variety of dishes, including soups, stir fries and sauces. Maitake have a more mild flavor than shiitake. They may also be used in many different dishes [see recipe below] and can be used as a substitute in recipes that call for button, morel or crimini mushrooms.

Reishi is also used as an immune support, and has been shown to help treat long-term infection, like chronic bronchitis. It is most often taken as a tea, and all of these mushrooms are available in supplement form. If you’re choosing to take mushrooms as supplements, the most effective form is a hot water extract, which may be drunk as tea or taken in capsules.

2. Black Elderberries
With their sweet taste (when cooked!) and antiviral properties, black elderberry is a great choice for kids and those looking for a gentle way to stave off colds and flus. Black elderberry fruit has been used for many years as a naturopathic flu remedy, usually made into a syrup. It contains lots of vitamin C and can be taken both for prevention of colds and flus or as an acute treatment. If you find them fresh, avoid the unripe berries—and eat them cooked.

3. Garlic
Garlic is a well known antimicrobial food. It is given to treat infection, as it is active against viruses, bacteria, parasites and fungi, but also seems to increase the potency of certain immune cells. Garlic also has a host of other health benefits (it’s anti-inflammatory, protects against heart disease and helps regulate blood sugar, to name a few). A variety of different compounds give it such a wide range of therapeutic effects, and the greatest number of these are found in raw garlic (bruschetta, anyone?). Using it fresh provides the most benefit overall, but in terms of the immune system, eating it cooked can also be helpful.

4. Sauerkraut, Other Fermented Foods
In naturopathic medicine, we often talk about how the digestive system is the foundation for the body’s overall health. The digestive tract is home to much of the immune system, so keeping it healthy is hugely important. One key factor in digestive health is having balanced intestinal flora. Many of us think of yogurt when we think of foods that provide good probiotic flora, but another good choice is sauerkraut or other fermented foods. Besides being a good source of flora, sauerkraut also provides glutamine, which acts as food to the cells of the colon. Sauerkraut juice is also an old naturopathic remedy for stomach flu.

5. Dark-Colored Vegetables
Dark, leafy greens, brightly pigmented roots, and orange, green or red vegetables generally tend to contain high amounts of a variety of nutrients. One of the most important of these is beta-carotene, which is both a strong antioxidant and increases levels of certain types of immune cells. Beta-carotene, and similar carotenoids, occurs in a wide variety of brightly colored vegetables. Some common examples are yams, tomatoes, spinach, carrots, kale, collard greens, apricots and squashes. Cooking actually seems to make carotenoids more available, so steaming your vegetables, or even better, cooking them in soup, can allow your body to make better use of these foods.

…And one to avoid

Refined Sugar
Sweets may feel like comfort food, but eating refined sugars dampens your body’s response to infections. Studies show that eating too much sugar causes immune cells to work less efficiently, meaning that the body is not able to respond as quickly or as strongly to infection. When you’re starting to feel under the weather, it’s really important to avoid sugars, as they can reduce the activity of cells which fight infection. To make sure your immune system is working as well as possible, it’s important not only to eat fewer sugary foods, but also to look for hidden sugar by reading labels. All kinds of processed foods may be sweetened, from pasta sauces to salad dressings.

The food you eat helps to set the stage for your overall health, immunity and well-being. We at San Francisco Natural Medicine are happy to help you plan a strategyfor maintaining good health this winter. Call for an appointment to tonify your immune system and prepare for cold and flu season.

Immune-Boosting Maitake Mushroom Pesto

Chop Maitake in a food processor, saute on medium heat (without oil) until the water in the fresh mushrooms is released, stir in some olive oil, a little garlic and salt and pepper to taste. Some fresh parsley is nice too.

Uses For Maitake Pesto:
Over pasta with grated cheese, on toasted bread or garlic bread as an appetizer, sprinkled on pizza.