Boosting the immune system
Last weekend we froze...this week calls for shorts and it is absolutely beautiful. What a change in the Florida temps. Regardless of where you live, the weather is going to change and you will likely find yourself around people fighting colds or the flu. I haven't gotten the flu shot in a good 5 years. I believe my immune system is pretty strong. Sure, exercise, good sleep and minimizing stress helps with maintaining a healthy immune system but more than anything, the diet plays a critical role in how our body fights off infection.
I find it amazing that I don't get sick. Despite training for Ironman's, working out in gyms, interning outside the home (school, nursing home, etc.) and traveling, I feel as if my immune system stays strong because of the foods I emphasize in my diet and because of the foods I de-emphasize in my diet. Yet another reason to take pride in wholesome and natural foods. Of course, even the most nutritious diet does not ensure that a person won't get sick but it can really help to prevent a weak immune system.
Sure, I've gotten a sniffle or sore throat here or there but in the last 4 years I have only been sick two times (for a total of 3 days) which caused me to be in bed, without energy. I guess when it rains, it pours.
There are a lot of claims on foods for "immune support" specifically during the fall and winter months. Because infectious diseases are the leading cause of morbidity in the world, it is important that you protect your body against the possible invasion of harmful substances such as bacterias, virus's, chemicals and possibly cancer. Also, a healthy immune system helps your skin, digestive system and inflammatory responses.
There was a great article in the Nov 2010 (volume 33, number 11) issue of Environmental Nutrition. Another great newsletter that comes to my mailbox on a monthly basis.
Since there is a lot of confusion (and misleading) when it comes to immune system defenses, I thought I'd provide you with a little of the article to help you build a powerful and healthy immune system.
Many people believe that vitamin C boosts immune function and help fights cold. Unfortunately, according to the National Institutes of Health, more than 30 clinical trials have examined the effects of vitamin C on cold prevention, yet overall they don't support a significant reduction in risk. Still there's no harm in pushing vitamin c-rich foods, such as papaya, red peppers, broccoli, strawberries , citrus, and tomatoes as part of your healthful diet.
Its documented role in the immune system has led immunology researchers to study vitamin E. In a 2004 study led by Meydani, published Aug, 18 2004 in The Journal of the American Medical Association, vitamin E supplementation was found to reduce the risk of upper respiratory infections in particular the common cold. Foods packed with vitamin E include nuts, olives and leafy greens.
Studies show that people with low serum zinc levels experience twice the frequency of pneumonia (as well as longer duration and more antibiotic use) compared with those who have adequate zinc levels, according to Meydani. But when it comes to the common cold, "the jury is still out. Some studies show zinc helps and reduces duration of colds, while other studies don't show the effect" says Meydani. Zinc food sources include red meat, poultry, seafood, beans, nuts and cheese.
While the evidence isn't strong, scientists recognize that the sunshine vitamin may have important functions within the immune system. In addition to sunlight, you can find Vitamin D in fortified dairy products and mushrooms, salmon and sardines.
These live microorganism can exert health benefits by improving the number of beneficial bacteria in the gut. "several studies show that the right types of probiotics increase the immune response" says Meydani. Only certain strains of probiotics have been tested for immune benefits, thus, it's important to look for clinical proof.
Curiously, mushrooms have captured scientists' attention in immune research.
The WHOLE FOOD approach. So should you take mega-doses of essential nutrients to boost your immune system? "We can't say with certainty. Sometimes if you supplement at more than the required level of nutrients, the immune function can decrease. It's not always the case that more is better," says Meydani. In addition, nutrients appear to impact people's immune system differently. Meydani explains that people can be "responders" or nonresponders to particular nutrients, depending on genetics.
Many food companies and the media have made overly exuberant claims about the ability of particular foods to power up the immune system. It's important to keep in mind that foods contain a synergy of nutrients that work in unison to provide health benefits versus supplements which only provide one or two nutrients. The best approach for fostering a healthy immune system is to eat a nutrient-rich diet that meets all of your body's needs. Here's more reason to make every bite count, with delicious, whole foods bursting with nutrients.
-Sharon Palmer, R.D
(Simin Meydani - D.V.M. Ph.D. director of the Jean Mayer USDA Human Nutrition Research Center on Again and the Nutritional Immunolgy Lab at Tufts.
Not sure if you noticed it, but I didn't see any suggestions for Special K cereals or bars, Smart Balance butter, Dannon Yogurt, Kashi cereals, agave sugar, almond milk, nature valley granola bars or Odwalla Pomegranate juice. Are these foods bad? Certainly not. Remember, there are no bad foods.
I think it is time for a fruit and vegetable revolution. No longer should fruits and veggies be viewed as "diet foods". The foundation of a lifelong diet should be plant-based. And to keep things balanced, society needs to realize the power in whole grains (carbs), healthy fats (unsaturated), low fat dairy and lean/vegetarian protein. It's time to stop counting/cutting out calories and feeling hungry all day. It's time to stop the sugar and salt cravings from processed food. Let's focus on the foods that we put in our body and whether or not they positively impact our lifestyle as well as our individual athletic and body composition goals. Happy eating!