Primer on Probiotics

Good article by by Katherine Fisher in the HawaiiHealthGuide.com.

A reader writes in to say that she had taken a course of antibiotics and now had diarrhea. Because antibiotics indiscriminately kill off intestinal bacteria, the good as well as the bad, the result is often symptoms of lactose intolerance even in people who usually don't show those symptoms.

The explanation and recommendations are good, so I'll excerpt extensively:

What are probiotics?

Probiotics are small organisms that help maintain the natural balance of organisms (microflora) in the intestines also known as gut flora.

The normal human digestive tract contains about 400 types of bacteria that reduce the growth of harmful bacteria and promote a healthy digestive system.

The largest group of probiotic bacteria in the intestine is lactic acid bacteria, of which Lactobacillus acidophilus, found in yogurt and kefir is the best known. Yeast is also a probiotic substance. Probiotics are also available as dietary supplements containing potentially beneficial bacteria or yeast, with lactic acid bacteria (LAB) as the most common microbes used.

LAB have been used in the food preparation and manufacturing for many years, because they are able to convert sugars (including lactose) and other carbohydrates into lactic acid and acts as a preservative by lowering the pH and creating fewer opportunities for spoilage organisms to grow. This organism is also responsible for the characteristic sour taste of fermented dairy foods such as yogurt.

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Where do I find probiotics?

Fermented Dairy foods such as kefir and yoghurt are easy sources of ingesting probiotics.

However, look closely at the label to determine if that yogurt is effective. To offer benefit, the yogurt must contain active cultures. Most yogurt containers indicate whether active cultures are present

Taking probiotic supplements (as capsules, powder, or liquid extract) can quickly help reestablish the colonies of the lost beneficial bacteria and thus help prevent diarrhea, but in Hawaii, be sure and check that these sources have been refrigerated, as the cultures are considered "live" and will die if exposed to heat.

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Managing Lactose Intolerance:

Because LAB convert lactose into lactic acid, their ingestion may help lactose intolerant individuals tolerate more lactose than what they would have otherwise.

There's much other good information in that article. You should take a look.