by Geeta Khare, M.D.
I hear a lot about the health benefits of yogurt. What is this about?
Much of the discussion about the health benefits of yogurt have to do with the active cultures that are in yogurt and the way these cultures can help us stay well.
What conditions can be benefitted with active cultures?
There are a wide variety of conditions that seem to benefit from intake of cultures. Most of these conditions are primarily gastrointestinal illnesses but there are other conditions and illnesses that are also being studied. There are some studies to suggest that probiotics may be beneficial in hayfever and eczema. Though there needs to be more research. As the science continues in this area, there may be some studies that show benefit and some that do not. Over time, the data will reveal more information about which illnesses truly benefit from improving our gut flora.
What are active cultures?
Active cultures are the bacteria or other organisms (for example, yeast) that are used to ferment milk and turn it into yogurt, kefir and other specific dairy products. Other fermented foods also contain active cultures. These foods include certain types of bread, kimchi (a fermented Korean cabbage dish) and many other foods.
Bacteria? Can that really be good for you?
We are all colonized on our bodies with bacteria, viruses, and yeasts already. We have millions of these organisms on our skin, mouth, gut and other mucous membranes.
But I thought bacteria caused infection. Shouldn’t we try to kill these germs?
There is a difference between “commensals” and “pathogens”. Commensals are those organisms that live harmlessly on our bodies and pathogens are those that cause disease. Sometimes the commensals are referred to as “good bacteria” and pathogens are referred to as “bad bacteria”.
So if we already have good bacteria on our bodies anyway, why would we need to add bacteria with active cultures?
Various illness, stress, antibiotics and other medications can kill some of these good bacteria. When that happens, pathogens can take their place. Also, if one particular population of commensals over grow and disrupt the balance of all the different types of bacteria present, the commensal itself begins to behave like a pathogen.
What about other types of germs?
It is true that we are colonized not only with bacteria, but also with other microorganisms such as fungi/yeast and some viruses. There is ongoing research into these other members of our “normal flora” but at this point, more is known about the bacteria inhabiting our body.
Is there any particular brand of yogurt that is best?
There are many brands of yogurt and often some of these brands have “trademarked” bacteria used in them. It is unknown at this point if there is one particular bacterial species that is truly superior to another. Some people will respond better to one particular bacteria or another but this varies widely from person to person.
What about frozen yogurt?
In general, you need to use something in which the bacteria are alive. There is some concern that freezing, shipping, storage and similar can kill or otherwise disrupt the bacterial culture. It is best to use the freshest type of yogurt available. Some people will even make their own yogurt to make sure they are getting fresh, live, active cultures.
What do you do if you are allergic to dairy or don’t like yogurt?
If you cannot tolerate dairy products, you can try probiotic supplements which contain bacterial cultures. Of course, since these are “Dietary Supplements” there are issues of quality and purity since they are unregulated. Be sure to check with “watchdog groups” such as USP or ConsumerLab to find a high quality supplement.
Are there any risks of taking active cultures?
As with any medication or lifestyle change, there are always pros and cons. There is some concern about whether people with immunodeficiency (weakened immune system) should take probiotics. Talk to your doctor about these risks and benefits and find out which of them apply to your specific situation.