Most likely you've heard about probiotics and their health benefits - but what exactly are they and how can they help you? The scientific definition of a probiotic is a bit complicated. Live microorganisms, including Lactobacillus species, Bifidobacterium species and yeasts, that may beneficially affect the host upon ingestion by improving the balance of the intestinal microflora. The easy definition? "Friendly bacteria".

Good sources of probiotics include kefir, acidophilus milk and fermented foods such as miso and tempeh. You can also purchase nutritional supplements that contain probiotics. There is a misconception that grocery store style yogurts provide a significant amount of probiotics. However, yogurt starter cultures are not necessarily resistant to the digestive properties of the body, resulting in smaller numbers reaching the gastrointestinal tract.

Over the centuries, probiotics have been attributed to a multitude of health benefits. They are particularly helpful for gastrointestinal disorders such as diarrhea, traveler's diarrhea, peptic ulcers, irritable bowel syndrome and inflammatory bowel disease. Probiotics slow down the growth of harmful bacteria in your digestive system. They improve vitamin absorption and food digestion and stimulate your body's natural defense systems.

Over 50 million Americans suffer from high blood pressure. Probiotics have been associated with antihypertensive effects in both animals and adults with mild hypertension. Furthermore, many agree that taking probiotics may decrease your cancer risk. They can detoxify ingested carcinogens and produce compounds that inhibit the growth of tumor cells.

For the women, probiotics are a must when taking an antibiotic.  The antibiotic kills the bacteria causing your infection but while it kills the bad bacteria it is also killing your "good" bacteria. This results in an uncomfortable yeast infection and even more medicine to take. If you take probiotics while on an antibiotic regimen, you may avoid the inevitable trip to the drug store for a yeast infection treatment. Both men and women can benefit from probiotics during a round of antibiotics if they suffer from diarrhea during the course.

There are several ways you can include probiotics into your diet:

• Kefir - Kefir grains can be purchased in a live form or dried. Kefir looks a bit like a cottage cheese lump, and is fermented in milk at room temperature for about a day at a time. The kefir is strained and the milk is ready to drink. The grains are then placed in a new container of milk with a bit of the previous milk included. The taste is yeasty and milky, and can be either taken plain or mixed with honey, in smoothies, mixed with beans or more. Kefir contains more good bacteria than yogurt and also provides a complete protein, essential minerals and B vitamins.
• Acidophilus Milk- Acidophilus milk is whole milk with an added acidophilus culture. It is thicker than milk and contains this beneficial bacteria.
• Fermented Foods - Foods such as miso and tempeh contain probiotics. Fermented foods do not contain as much healthy bacteria as kefir and acidophilus milk, and therefore may not survive the entire intestinal track providing less benefit but certainly still beneficial.
• Probiotic Dietary Supplements - Bacteria can be purified, concentrated, dried and placed into powders, capsules or tablets.