A healthy immune system is a defense against pathogens, such as viruses, bacteria, and
carcinogens that can make you ill. Immune cells are found throughout your body – in your
tonsils, lymph nodes, spleen, thymus gland, and bone marrow. By focusing on nutrient-rich
foods instead of high-calorie foods like cookies and ice cream, you and your family can ward off
illness.

1. Go Fishing
For a stronger immune system, nutritionists suggest consuming at least two servings a week of
fatty seafood, such as sardines, salmon, herring, and mackerel. The omega-3 fatty acids in
these fish and in other foods such as walnuts, flaxseed, and canola oil are known to boost the
immune system and reduce inflammation in the body by increasing the activity of while blood
cells called macrophages, which engulf troublesome bacteria. Monounsaturated fats in foods
such as olive oil and wheat germ also protect our bodies from microorganisms, bacteria and
viruses. In fact, researchers have found that diets low in fat weaken the immune system and
increase depression.

2. Pick Protein
Zinc, a mineral abundant in meats like calf’s liver, beef and lamb, works with protein found in
meat to help to strengthen the immune system. (Vegetarians can get their zinc from whole grains
and fortified breakfast cereals.) In fact, certain types of immune cells, including white blood cells,
cannot function without zinc. Other proteins that can help reinforce your body’s defense system
include chicken, fish, tofu, eggs and dairy foods.

3. Reach for Plant Foods
By serving your family a variety of fruits and vegetables at meals and for snacks, you ensure
that their bodies get plenty of phytonutrients. These compounds help boost your immune
system, strengthen your heart and blood vessels, and even fight some cancers. In the winter
months, most markets offer a wonderful array of fresh choices, from winter squashes, greens
and root vegetables to cranberries. And you can always reach for canned and frozen fruits and
vegetables. Processed just after harvest, canned and frozen produce can actually sometimes
have more nutrients than produce that has spent days in transit.

4. Don’t Skimp on Citrus
Go ahead and indulge in leafy greens, bell peppers and citrus fruits like oranges and grapefruit,
all rich in vitamin C. This vitamin inactivates histamine, the substance responsible for your runny
nose and congestion, and helps reduce the inflammation that accompanies colds and viruses. In
fact, according to a study at the University of California at Berkeley of 160 healthy adults, those
who took 500 milligrams of vitamin C a day for two months had a 24% drop in C-reactive protein,
a protein associated with inflammation and chronic disease. Brightly colored greens and other
vegetables also contain large doses of immune-enhancing antioxidants that help fight wintertime
illnesses. So, load up on strawberries, cantaloupe, blueberries, tomatoes, broccoli, and sweet
potatoes – all a boon for your immune system. To make winter and spring vegetables more
appealing, consider adding some to soups, stews and sauces. And down a glass of low-sodium
tomato or vegetable juice now and then – they’re both great sources of vitamin C.

5. Go Nuts
Instead of chips or cheese doodles for an afternoon snack, reach for a handful of nuts or
seeds.  Studies show vitamin E, a powerful antioxidant, fights respiratory infections, including
colds. It boosts the responses of antibodies and certain immune system cells when we’re under
stress – and who isn’t? A quarter cup of sunflower seeds has almost all the vitamin E you need
daily. A quarter cup of almonds provides 50% of your need. And Brazil nuts pack a whopping
dose of selenium, a mineral that also boosts wintertime defenses.

6. Hit the Spice Rack
Both garlic and onions contain compounds that rev up the activity of immune-system cells called
natural killer cells and T-helper cells.  While they’re fending off colds, they’re also helping
defend us from cancer and heart disease – not a bad side activity at all. If a cold does catch you
and you get stuffy, a bite of garlic will also help clear your nose (not to mention the room).

7. Spoon in the Yogurt
In a year-long study at the University of California, adults who ate three-fourths cup of yogurt a
day had 25% fewer colds that those who didn’t. The yogurt cranked up the production of a
substance called gamma interferon, which helps squelch virus reproduction, a death knell for
your cold.

Dehydration can also lower your defenses. Drink at least eight 8-ounce glasses of water and
other fluids every day. And if you’re already sick, double that.

Now you know what to eat. But what foods should you avoid?

Skip Sugar and Fat
Even as little as two sugary sodas a day can lower the power of your immune cells by 40%. And
animal studies have shown that diets high in both sugar and fat reduce the numbers of natural
killer cells.

For a healthy immune system, health experts also encourage reaching a healthy weight, taking
a multivitamin that provides essential minerals (like zinc and selenium), exercising 30 to 60
minutes most days, and sleeping at least eight hours every night.
A Healthy Immune System