More and more research is showing the importance of these good bacteria found in our digestive systems. They play a role in dissolution, absorption and digestion of nutrients, elimination of toxins, hormone balance for men and women, regulating cholesterol, immune system function, regulating blood sugar, helping decrease inflammation...and on and on the list goes.
Because all of us subject our bodies to things that decrease the population of the good bacteria, for example, stress, coffee, fast food, alcohol, OTC (over-the-counter) meds that decrease stomach acid and, most importantly, antibiotics.
Some foods that support our good bacteria are: garlic and onions, which act as fertilizer for them. Some food sources of probiotics are sauerkraut, kim chi, kefir, and yogurt. These are all fermented foods.
Yes! Probiotics are available in capsule, powder and liquid supplements. They are most often measured in billions, which indicates the actual number of bacterial population in the dose.
There is not a set Recommended Daily Allowance (RDA), but I usually recommend around 20 billion units per day with the evening meal.