Dr. Michael E. Rosenbaum, MD
With the New Year comes flu season. Because of this, the festive but not-so-healthy foods you may have been eating during the holidays can set you back before you even have a chance to work on your resolutions. That’s because what you eat can impact your immune system health dramatically.
As you’ll soon discover, how you feasted may determine whether you spend a week on the couch fighting the flu . . . or focused on your new goals and plans.
But don’t worry—by getting extra helpings of the five immune-supporting foods I mention here, you’ll be giving your immune system the nutrition it needs to do its job right. If you feast right this winter, you’ll keep your defenses strong.
But before we get into the stellar immune foods to load your plate up with, let’s start with something you should go light on . . .
Sugar: The Immune-Busting Food
It’s kind of a double whammy . . . Just when the threat of getting sick is at its highest, we get hit with a festive parade of holiday sweets. Why is this a problem? Sugar drops your immune system down to all-time lows.  It only takes about 75 grams of sugar (about two cans of soda) to decrease your white blood cells’ ability to attack and destroy invading bacteria. And even worse, these immune-busting effects last for several hours after you eat the sugar.
So perhaps a modest holiday treat here or there is okay. But beware . . . if you don’t exercise some caution with this dangerous sweet stuff, you might find yourself in bed with the flu, unable to enjoy the New Year at all.
Okay, enough said about the bad stuff. Let’s move onto the good stuff, starting with . . .
Immune-Boosting Food 1: Cranberries
While we usually associate these cheery berries with fighting urinary tract infections, they also have a mounting pile of evidence behind their immune boosting power. Research conducted at the University of Florida at Gainesville Food and Nutrition Institute showed that after just 8 weeks of eating them regularly, these bright little fruits enhanced immune cells and primed them to be ready to defend you. 
Cranberries as sauce, juice or even dried can all give you some of cranberry’s immune boosting help. But for best effects, look for recipes with minimal refined sugar, sweetened with other fruits or fruit juices instead.
Immune-Boosting Food 2: Squash
Just the sight of squash’s bright orange and yellows is enough to make you feel better. But it’s not just their looks. Squash is high in beta carotene. Your body turns beta carotene into vitamin A. Vitamin A plays a key role in helping your immune system cells differentiate. In other words, it helps your immune cells develop expert specializations so they can protect you better.
Do you love squash’s nutty sweetness so much you could you eat squash all winter long—not just over the holidays? You’re in luck! Apparently the beta carotene supplies in squash increase over time as they sit in storage. So save a few for a post-holiday immune fortification feast.
Immune-Boosting Food 3: Garlic
This spicy bulb is an immune powerhouse. When volunteers took a garlic supplement daily for three months, they experienced significantly fewer colds and spent significantly less time being sick than the placebo group. There’s a trick to using garlic to stay healthy, however. Garlic is really only effective when its unique sulfur compound, called allicin, starts to decompose. To get the decomposed allicin in your system, make sure you chop up your garlic and then wait for 10 minutes before cooking with it or mixing it with acids. This way you can be sure to get garlic’s full fortifying effects.
Immune-Boosting Food 4: Oats
Oatmeal is the perfect warming winter breakfast. And not just because it’s hot . . .
Oats are high in beta glucans, which are special carbohydrates that have been shown to help with immunity. Beta glucans seem to speed up your body’s ability to locate invaders. And they seem to boost some immune cells resistance to viruses. In one study on firefighters, researchers found taking beta-glucan supplements daily reduced their rate of getting a cold by 23 percent.
When you combine oatmeal’s immune-boosting beta-glucans with its heart-healthy fiber, you’ve got a great counterbalance to the holiday’s rich fare. Sprinkle in a few cranberries or stir in some pumpkin puree and you’ve made it even more of an immune-boosting superfood. (Hint: You can probably hold the garlic!)
Immune-Boosting Food 5: Chlorella
Chlorella alga has never been a traditional holiday food, mind you, although it is a festive green color. But there’s a reason I advocate chlorella so much, especially around the New Year. Chlorella . . .
• Gives you more beta carotene ounce per ounce than most vitamin-A rich foods.
• Boosts your immune system on many fronts.
• Is a rich source of defense fortifying beta-glucans.
And best of all—not only is chlorella outstanding nutrition for your immune health—it’s easy. You don’t have to bake or baste it. All you have to do is take a small handful of tablets in the morning . . . And oh yeah, and did I mention chlorella is sugar-free?
So don’t miss out on starting the New Year healthy and happy. Get second helpings of these immune boosting foods and be merry!
Dr. Michael E. Rosenbaum is a 35-year veteran and widely recognized pioneer in the field of nutritional medicine, alternative healthcare and medical acupuncture. As one of America’s most respected experts in natural health and healing, Dr. Rosenbaum has been a frequent lecturer to professional medical groups and has participated in numerous television and radio talk shows. He is also an esteemed member of the Sun Chlorella Advisory Board, which helps guide the medical innovation behind Sun Chlorella products. Visit his website at drmichaelrosenbaum.com.
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