You can beat the nasty bug that's going around right now -- without a flu shot!

JJ Virgin: Just when you think you're out of the woods for a few days and your son didn't pick up that nasty cold going around second grade, you hear a familiar cry: "Mommy, I don't feel so good." Now, it's your daughter who has the sniffles and a sore throat. You close your eyes, knowing that it won't take long until the entire house is reaching for a box of tissues and hunkering down under the covers for several miserable days.

Are there real ways to avoid colds and even this scary new flu through eating and exercise? You bet!

I have a few lifestyle strategies that you can start today to give your family a naturally healthy booster shot when it comes to good health during these winter months.

• Make sure you're getting enough vitamin D. For those who live in cold weather places, the vitamin D you naturally get from the sun goes away during the months that you hibernate indoors. Vitamin D is a very powerful immune system modulator. I suggest still making sure you get about 15 to 20 minutes of sun each day during a nice walk, but skip the sunscreen, which blocks vitamin D. You should also ask your doctor to check your family's 25-hydroxy vitamin D levels. If you are low, you may need to supplement, but please be sure to do so with the advice of a professional.
• Calm down. Stress is very tough on your immune system at any time of the year, but it's also a great way to throw open the gates and invite a cold in. Stress reduces your natural killer cell activity and depletes vitamin C. Work on ridding your life of unnecessary stresses, and say "no" to that bake sale or babysitting your neighbor's five children. Also add fun activities to your day like a silly movie, because laughter reduces stress. Run around the yard with the dog or play a game as a family. Anything that chills you out will keep the chills of a fever at bay.
• Sleep more. Sleep is a wonderful way to rejuvenate and repair all of your cells. Lack of sleep lowers your immune system, which is especially dangerous this time of the year. Make sure you get seven to nine hours of high-quality sleep each night so your body can go through all of the important repairing sleep cycles. Cat naps do not count. Even one night of less than 7-9 hours of slumber can impact your immune system in a significant way.
• Get rid of the sugar. If you eat sugar, it will lower the ability of your white blood cells to kill germs by as much as 40 percent. This is the time to make a nice lateral dessert shift to delicious berries instead of cookies. Add some slivered almonds to the top. Yum!
• Exercise. Do high-intensity burst exercises to blast fat and boost your immune system. Steady endurance training like jogging or cycling can lower your immune system directly after your workout. When you do bursting or interval training (a fast burst for 30 to 60 seconds), recover for twice as long, and repeat to accumulate four to eight minutes of bursts, then you're teaching your body how to handle stress better without compromising your immune system.

JJ Virgin, PhD, CNS is a celebrity health and nutrition expert, author, public speaker and media personality. She is internationally recognized as the creator of the Weight Loss Resistance Revolution™ and trains other health care professionals in her program. JJ is the President of the National Association of Nutrition Professionals, nanp.org