Biology/Bacteria
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Question
I've seen a lot of commercials about yogurt, that say that
it has "10 billion bacteria!" How does that bacteria
survive the acid in your stomach, and affect your immune
system?
Hi Tristan: Thanks for your question.
The short answer is that they don’t survive, at least not in high numbers. Aside from the acid in the stomach, they need to survive the bile salts secreted by the liver. These are potent bacteriocidal agents.
So if your dose were 10 billion bacteria that would be
10,000,000,000 (we scientists don’t write all those zeros, we use exponents) so it would be 10*9 ( for 9 zeros). So if only 10% of them made it through, that would be 10*8, or 1,000,000,000. Plenty of bacteria left to do the trick!
Here’s a reference:
http://www.ajcn.org/cgi/content/full/73/2/399S?maxtoshow=&HITS=&hits=&RESULTFORM...
Hope this helps, write back if you have more questions.
FM Rollwagen, PhD
*sorry, the format won't let me do exponents. So just imagine that the * is for exponent.
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Answers by Expert:
Florence M Rollwagen
Expertise
I can answer questions in biology, microbiology and immunology on the undergraduate or graduate level. I can also address medical and health concerns regarding alternative medicine, autoimmune diseases (lupus, MS) liver disease and intestinal problems.
Experience
I have over 20 years experience in research and teaching at the medical/graduate level, and 5 years teaching college biology and microbiology. My expertise is in microbiology and immunology, specifically the biology of cytokines and soluble immune response modifiers. I also carried out original research in blood substitutes and shock/trauma.
Organizations
American Association of Immunologists (AAI)
American Association for the Advancement of Science (AAAS)
Publications
Journal of Experimental Medicine, Journal of Immunology, Cytokine, Shock, Experimental Hematology
Education/Credentials
BS biology 1966
MS biology 1968
PhD immunology 1979
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