Dear Dr. Klaper:

I’ve been told to consume acidophilus bacteria after taking antibiotics. What is the best kind of acidophilus and how do I know if the bacteria I have purchased are really alive? – B.P.

Dr. Michael Klaper answers questions on a wide variety of health and nutrition-related subjects.
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Dear B.P.,

Keeping the resident population of bacteria in the intestinal tract healthy is essential, especially after taking a course of antibiotics. A population of “friendly” bacteria is required not only for the health of the intestines, but also to inhibit overgrowth with yeast and “unfriendly,” pathogenic bacteria. Normal bacterial flora also help to prevent increased intestinal permeability (“leaky-gut syndrome”), which can lead to joint inflammation and autoimmune diseases. Consequently, ingesting a preparation containing health-enhancing bacteria is often a very good idea.

The most health-promoting organisms in our intestines are the family of Lactobacillus bacteria, especially Lactobacillus acidophilus, along with its friendly cousins, L. plantarum, L. salivarius, L. bulgaricus, L. casei, L. bifidus, and others. Although not scientifically quite accurate, the Lactobacillus family of bacteria has come to be known as “acidophilus.”

The product with these beneficial organisms, combined with nutrients such as fructo-oligosaccharides (F.O.S.) and other substances to support their growth, is called a “probiotic.” The growth-supporting nutrients alone are termed “pre-biotics.” (If you have colitis, Crohn’s disease, or another condition involving inflammation of the intestinal tract, you should purchase acidophilus without F.O.S., since sugars of most kinds tend to make these inflammatory conditions worse.)

Certain organisms appear to be especially beneficial for specific conditions: 

• Lactobacillus plantaris has anti-inflammatory properties, making it especially valuable for people with inflammatory bowel disease, like Crohn’s disease or ulcerative colitis.

• Lactobacilis acidophilus is valuable for rebalancing the bowel after taking antibiotics, and for thwarting recurring urinary infections in women.

• Sacchromyces boulardii is effective in stopping diarrhea, either from antibiotics, radiation to the pelvis, or “travelers’ diarrhea.” It can be used as a preventative if one is traveling to a destination where contracting diarrhea is a strong possibility, in which case it can be started 2 to 3 days before departure and taken each day while traveling.

The beneficial organisms must be put into the gut in substantial numbers. A good probiotic product has between 3 and 15 BILLION organisms per dose. (This is often expressed as colony forming units or cfu’s.) For severe derangements of the intestinal flora, this dose may need to be doubled. This is why I think eating yogurt as a probiotic is pointless. Standard, commercial yogurt is pasteurized to kill bacteria before it is sold, so it is useless as a probiotic source. The “cultured” or “bacteria-fortified” yogurt products have a few million organisms, at best. Thus, you would need to consume dozens of tubs of yogurt to produce any beneficial effect. Why consume all the dairy protein and sugar inherent in these products when all you really want is the beneficial organisms you can purchase purely in a good probiotic product?

It is very important to be sure that the acidophilus product you’re paying for and ingesting really contains live, beneficial bacteria. That is, the organisms may have been quite viable when they left the factory, but if they were stored in an unrefrigerated warehouse and/or shipped on an unrefrigerated truck, by the time they get to the shelf of your neighborhood health food store, it may be dead, white powder. So, how do you tell?

Test it!

You can determine the “vitality” of your acidophilus product with a simple kitchen “experiment.” Start by pouring one quarter cup of soy milk (cow’s milk will also work) into each of two small bowls and then stirring in one teaspoon of acidophilus powder (or the contents of 4-6 “Vegicaps”) into one of the bowls.

If your probiotic comes in tablets or “enteric pearls” you must crush them up into a powder to assure adequate contact with the milk. Do not just drop an intact tablet into the bowl. Place the tablet in a plastic bag and using a hammer wrapped in a thin towel or the bottom of a heavy drinking glass, pound the tablet into a powder, and then add it to the milk.

Allow both bowls to sit out at room temperature overnight. When you examine the bowls in the morning, the milky contents should not look the same. Since Lactobacillus acidophilus is the bacteria that curdles milk, there should be signs of bacterial activity in the bowl containing the acidophilus. You should see either (a) lumps of curdled soymilk, or (b) a film of yogurt, or (c) bubbles of carbon dioxide, and if you put your nose near the milk, it should smell like sour milk.

If both bowls look the same, let them sit out on the counter one more night. The next morning, when you pour the contents of both bowls down the sink, if the physical characteristics of the white liquids appear to be the same, you have a non-viable product and should get a fresh supply, a different brand, or your money back.

Probiotics are best consumed one hour before meals or two hours after eating. The rationale for this is because you want to have as many live bacteria as possible pass through the stomach into the small intestine. When you eat a meal, your stomach fills up with hydrochloric acid which would kill most of the beneficial organisms. So, to “sneak” the bacteria through the acid vat of your stomach, it is wise to ingest the acidophilus prior to eating, before the stomach fills up with acid – or well after it has emptied.

Since modern life – with its steady stream of chlorinated drinking water, alcoholic beverages, antibiotic-laced foods, etc. – often presents an intensive assault on our normal intestinal flora, everyone could probably benefit from a “freshening up” of their intestinal bacteria with a brief one to two-week course of acidophilus, several times per year. Certainly, after a course of medically-prescribed antibiotic therapy, the healthy balance of bacteria should be re-created in the intestine by consuming an acidophilus preparation for two to four weeks after the last dose is taken. It is okay to take the probiotic while you are taking the antibiotic, just space them out in time – that is, if you take the antibiotic mid-day, take the probiotic in the morning and/or evening.

Probiotics are more likely to retain their potency when kept in the refrigerator, though not all brands require this. If there is any question about the potency of the product you have purchased – test it! Try to consume the entire product within a few weeks of purchase, so that it does not lose its potency in the refrigerator or on the shelf.

Yours in health,

Dr. Michael Klaper

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