1. Chemical Pollution.There are more than 85,000 new synthetic chemicals in the environment today that human immune systems never had to deal with before.

2. Imbalanced Gut Bacteria. In health, there are more bacteria in the digestive tract than there are cells in the rest of the entire body! So it should come as no surprise that the largest portion of immune activity is generated in the gut.

Healthy bacteria in the gut (i.e., probiotics) work hand in hand with your immune system to keep out 'bad guy' infections. Unfortunately, the widespread use of antibiotics and antacids, along with a diet loaded with Candida-feeding sugar, has disrupted the bacterial balance, leading to an overgrowth of unhealthy bacteria and Candida — and a weakened immune system.

Probiotics can be very helpful, but it is critical to use a brand that has an enteric coating to protect the healthy probiotics as they pass through the stomach. Otherwise, they will be killed by your stomach acid, making them unable to fight off the bad guys.

3. Food Stripped of Enzymes and Nutrients. The enzymes that cause food to ripen are also needed by our body to digest the food. But food manufacturers have figured out that removing those enzymes during food processing prolongs shelf life.

This widespread practice has dramatically increased problems with not only digestion, but also immunity. Why? Without these enzymes, the proteins in food are only partially digested. And then those protein particles enter the bloodstream, where they're mistakenly identified as outside invaders — further stressing an already overtaxed immune system.

To put it in perspective, the weight of the protein in a hamburger can be thousands of times the total weight of all the viral particles when one has the flu.

4. Leaky Gut. To make matters worse, intestinal overgrowth of bacteria and fungi (yeast) like candida also weaken the barrier formed by our intestinal wall. This leaves our "border crossings" wide open for partially digested proteins to enter the bloodstream. (Candida is particularly tough for your immune system to handle because it's such a BIG organism. Think of a virus as the size of a period at the end of sentence. Now think of candida as the size of a house.)

5. Poor Sleep. Sleep rests and regenerates the immune system. In fact, sleep deprivation is a well-known method for weakening immunity, and the 21st century is a sleep deprivation experiment on a massive scale! In the last 130 years, the average night's sleep has plummeted from 9 hours to 6 3/4 hours, which has further weakened our immunity.

6. Sugar Overload. The amount of sugar in a can of soda can suppress immune function by 30% for three hours. The average American consumes 150 pounds of sugar added to their diet in food processing per year, which sours the disposition of the immune system. (Excess sugar also feeds candida, promoting yeast overgrowth.)

7. Zinc Deficiency. Zinc is a key player in keeping a healthy immune system. But this trace mineral is a frequent victim of food processing. In addition, but chronic infections and inflammation lead to further zinc losses in the body. This sets up a vicious cycle of low zinc causing more infections causing more zinc loss.

8. Imbalanced Hormones. Healthy functioning of your adrenal glands is a must for strong immunity. But because of non-stop stress, poor sleep, excess sugar and other factors, many people have either under- or overactive adrenal glands.