By Helene Wechsler, MD and Michelle Simon, PhD, ND

My two sons are now grown, but I fondly remember the “back to school” days when we went to the store to get a long list of supplies and new clothes. I also remember dreading the seemingly endless array of germs that they would be exposed to every day, and often bring home.

Our immune system is amazingly complex. When working properly, it identifies and attacks foreign invaders such as bacteria, viruses and fungi. However, our children enter the world with an inexperienced immune system and, over time, build up their immunity by fighting these germs. Most pediatricians consider it normal for elementary school-age children to have six to eight colds a year.

A poor diet, chronic stress, and not getting enough sleep or exercise can result in a weakened immune system. Here are some tips I picked up along the way in an attempt to keep my children healthy.

Nine Healthy Habits to Adopt to Give your Child’s Immune System a Boost

1. Healthy Diet:

  • Eat a diet rich in fruits, vegetables, beans, fish, olive oil, nuts and grains. This type of diet is commonly called a Mediterranean diet. It has been studied extensively and has been repeatedly shown to enhance your immune system and help you live a longer, healthier life.1,2,3 Encourage your child to eat five servings of fruits and vegetables daily. This can be easily accomplished with a smoothie or by juicing. A diet rich in antioxidants can boost resistance to infection. Stay away from white foods such as sugar, white flour and white rice. Think about eating in color: dark green, red, yellow, and orange fruits and vegetables are packed with antioxidants. Other immune‐boosting foods include garlic, onions, ginger and mushrooms (reishi, maitake, and shiitake). In fact there are several studies evaluating the beneficial effects of old‐fashioned chicken soup.4,5
  • Eliminate toxic foods. Life is busy and it’s often hard to cook with fresh foods. As much as possible, avoid chemicals frequently found in commercial foods such as additives, artificial colors, flavors and preservatives.
  • Avoid sugar. Avoiding sugar is an important step in helping your kids thrive in school. The benefit of avoiding sugar was recognized as far back as 1976. Ringsdorf, Cheraskin and Ramsay found that drinking 24 ounces of sugared cola depressed the activity of bacteria eating neutrophils for a minimum of five hours.6 Eating sugar suppresses your immune system and your ability to fight infection, 7 which is especially important in the colder months.  Consuming sugar has been shown not only to decrease immune response, but also to increase systemic inflammation.8 Therefore, it will make your child  a good candidate for catching every cold and flu around.

2. Decrease stress:

  • Chronic stress is one of the biggest immune system-busters around. When we are under stress, our immune function is greatly impaired. Our body’s stress response of fight- or-flight releases cortisol, which in excess decreases our immune function. Periods of extreme stress can result in a lower natural killer cell count and sluggish killer T cells.9
  • Protect your child’s schedule. It is tempting to push our kids to be the best they can be, but our bodies react to over‐scheduling of activities with a stress response. Give your child time to play, relax and regenerate.
  • Be optimistic. A classic UCLA study in 1998 found that law students who began their first semester optimistic about the experience had more helper T cells mid-semester and more powerful natural killer cells than students who had a more pessimistic perspective.10
  • Laugh often. Researchers have found that the positive emotions associated with laughter decrease stress hormones and increase natural killer cell levels.11

3. Make sleep a priority:

Sleep is the way our bodies repair and heal. Do your best to make sure your children get enough sleep during cold and flu season. Sleep and the circadian system exert a strong regulatory influence on immune functions.12,13 How much sleep do kids need? A newborn needs up to 16 hours of sleep a day; toddlers require up to 13 hours,12 and preschoolers need about 10 hours. Adolescent and teenagers need nine hours of sleep daily. Teens also have a biological shift after puberty. They tend to fall asleep and wake up approximately two hours later than they did prior to puberty.14


4. Exercise as a family:

Moderate and fun exercise increases the number of natural killer cells and helps to de‐stress. It also releases endorphins that promote a sense of well-being and, in turn, enhances your immune system.15 To get your children into a lifelong fitness habit, plan fun family activities and be a good role model. Exercise with them, rather than just urge them to go outside and play.

 5. Get dirty:

The concept of exposing people to germs at an early age to build immunity is known as the ‘hygiene hypothesis.’ It is believed that early exposure to microbes is essential for normal immune development.16 So, start a garden and get yourself and your kids outside digging in the dirt.

6. Vaccinations:

Don’t forget to discuss the benefits and risks of vaccinations with your healthcare provider before school starts.

 7. Don’t overuse antibiotics:

  • The majority of childhood illnesses are caused by viruses. Antibiotics only treat diseases caused by bacteria. The use of antibiotics for treating uncomplicated viral infections is likely to do more harm than good. Antibiotics can create adverse reactions, as well as contribute to the development of drug-resistant bacteria and disrupt normal, healthy intestinal bacterial colonies.17,18
  • Instead of antibiotics, you could try supplements to boost your child’s immune system** such as: vitamin D19‐23, vitamin C24‐31, zinc32‐33, probiotics34‐36 and echinacea.37‐39
  • Honey is actually quite efficacious for cough symptoms in children older than 12 months. Three randomized, controlled trials were conducted that showed honey reduced the frequency and severity of coughs and improved sleep for patients and parents. Honey was found to be as effective as, and safer than, over the counter cough medication.40

 8. Put on a coat:

In July 2016, Yale researchers discovered that when human airway cells were infected with a rhinovirus (the virus that causes the common cold), the cells fought off the infection faster in warm body temperatures. When the cells were placed under below-normal body temperatures (91 degrees Fahrenheit), the cold virus replicated immediately; however, when the affected cells were placed under normal core body temperatures (98.6 degrees), the cold virus died off faster and was not able to replicate. Additionally, at warmer body temperatures the infected cells showed an enhanced activity of a crucial enzyme called RNAseL, which destroys and attacks viral genes.41 Therefore, it is important to make sure your kids bundle up in the winter.

9. Keep other members of the household healthy:

  • Guard against germ spread. Wash hands often with soap and water. There is no evidence that antibacterial soap is any more effective than regular soap and antibacterial soap can cause resistant strains of bacteria.42
  • Quit smoking and banish secondhand smoke. If you or your spouse smokes, quit. Cigarette smoke contains more than 4,000 toxins, most of which can irritate or kill a variety of cells in our body. Kids are more susceptible than adults to the harmful effects of secondhand smoke because they breathe at a faster rate and a child’s natural detoxification system is less developed. It is well known that secondhand smoke can increase your child’s risk of bronchitis, ear infections, and asthma.43


If all else fails, here’s a great recipe for “Greek Penicillin Soup”:

Avgolemono Soup (EggLemon Soup)

1 lb rice
2 lb chicken broth
I tsp black pepper
8 eggs, separated
Juice of 3 small lemons

Boil the rice, chicken broth and black pepper for about 15 to 18 minutes, or until rice is cooked. Beat the egg whites until frothy. In a separate bowl beat the egg yolks well and add them to the egg whites. While beating the egg mixture, add the lemon juice. With a small soup ladle take out some hot chicken broth from the soup pot and add it to the egg/lemon mixture slowly while constantly beating the mixture. Add the mixture slowly to the soup pot while stirring slowly. Remove from heat. Optional: Add 1 lb of diced white chicken meat to boil with the rice.


**As with any supplement, consult with your doctor and make sure the products you purchase are of the highest quality and purity.


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