Probiotics are healthy bacteria that live in the intestines and maintain the balance of beneficial microflora in the body.  Balanced microflora maintains a healthy digestive tract, decreases chances of intestinal infection, it eases IBS symptoms like gas and bloating, and they promote a healthy immune system.  It is not a cure all, and I recommend discussing the underlying causes of intestinal issues with your PCP (primary care physician) to ensure you're taking the right probiotics for your personal needs.

How are probiotics preventative medicine? 
From a microbiological stand point, "good" bacteria reproduces and spreads throughout the intestine, colonizing the colon preventing bad bacteria from  being able to reproduce and grow in the intestines.  Imagine a busy city where there are people everywhere, it is crowded and very difficult to gain space to spread out; 2 people cannot occupy the same space. Bacteria is the same way.  Your intestines is the big busy city, the more there is "good" bacteria in the city, the less bad bacteria can spread out to occupy the space.  This prevents infection.

When should you include probiotics in your diet?
As often as you can is my answer.  Especially during the cold and flu season and/or when you are taking antibiotics.  Why?  Because antibiotics are designed to KILL bacteria, which  is great if you have pneumonia, but they are not selective in the bacteria that they kill.  They kill good and bad bacteria alike, so when you take Amoxicillin, or Cipro, or a Z-pack, you are not only killing the bad bacteria, you are killing the beneficial bacteria, so you need to replace the good ones.  I prefer food sources to supplements, and to encourage their propagation, you can eat PREBIOTICS, that's foods that the bacteria love to eat and includes anything in the garlic and onion family.

What food sources include probiotics?
The easy answer is anything fermented.  Pickles, sauerkraut, kombucha, yogurt, cottage cheese, cultured milk or raw milk, etc.  Anything that says "live and active cultures".  In addition, you can ferment or pickle anything, pickled eggs, pickled asparagus (recipe posted earlier in this blog), pickled peppers or any other pickled vegetables. If you make your own fermented or pickled vegetables, make sure you follow a recipe that is tried and true to ensure that you safely ferment your vegetables.  There are bad strands of bacteria that can get in food. I recommend getting a recipe so you can try many recipes safely.  Once you are familiar with how to pickle and ferment vegetables, you can have allot of fun with it.  I know I do.  You can also make your own yogurt safely and easily.  Then you can add all your own fruits or honey to your home-made yogurt for a custom made easy breakfast.  Enjoy!