Wednesday, September 12, 2012

Microbes for Breakfast!

On the breakfast buffet table was a big bowl of white stuff the consistency of thick whipped cream.  The little sign beside it said "Yogurt." Normally I would have moved right on to the real food, since at that time I placed yogurt in the same "not-past-my-lips" category as cottage cheese (what are all those lumps, anyway?) and buttermilk (anything that leaves scum that thick on the empty glass can't be good).

This was in 2003, on our third trip to France. Previous visits had introduced me to some fabulous French food and although for most of my life I've not been very adventurous when it comes to eating I tend to throw caution to the wind when traveling there.  And so I tasted it.

Well, as has happened a few other times in France, I thought I had died and gone to heaven (two other occasions were when I tried my first chocolate croissant and when I took my first bite of Roquefort cheese).  This homemade yogurt stuff was rich and creamy and smooth and not quite like anything I had ever tasted before -- I loved it.  Wow, me eating yogurt -- wonders will never cease!

Since then I have become a real yogurt fan, and now I have it for breakfast (usually with granola my wife makes) almost every day, and when we travel I seek it out whenever possible. But those who know me will understand that I don't just eat it -- I've had to investigate it and research it so I can justify my recent passion for something I rejected for most of my life.  And what I've learned is that (a) yogurt is one of nature's most perfect foods and (b) many of its beneficial qualities come from a most unlikely source -- microbes, aka "germs."

Webster's defines yogurt as "a fermented slightly acid often flavored semisolid food made of milk and milk solids to which cultures of two bacteria (Lactobacillus bulgaricus and Streptococcus thermophilus) have been added."  Sometimes other strains of bacteria are also added.  Sounds yummy, right?  Fermented....semi-solid...bacteria...... Had I read this first I would never have tried it.

Yogurt can be made from the milk of cows (most common in the U.S. and Europe), sheep or goats (common in Turkey, where yogurt probably originated), and water buffalo (India & Egypt). Each of these has a different flavor and texture.  Greek style yogurt is strained to remove some of the liquid and is therefore thicker and a bit more tart.  Yogurt can be made from whole milk or from reduced-fat milk.  When the source is low-fat or non-fat milk the resulting yogurt has almost no cholesterol and the calories it contains are nearly all from protein, a very good thing from a health viewpoint (though there is some loss of flavor -- let's face it, fat tastes goooood).  Assuming the yogurt hasn't been adulterated by adding sweeteners, the nutritional qualities are remarkable.  It is a food that is high in protein, calcium, and several vitamins but low in fat and cholesterol.

But that's not all.  What about those bacteria?  It may be obvious that they are responsible for the fermentation process that results in yogurt, just like microbes are used to make beer, cheese, and wine.  However, in those cases the bacteria are pretty much finished once the job is done and they convey no particular health benefits of their own.  In yogurt, though, they continue to produce benefits even after the yogurt is consumed, assuming they are still alive (some manufacturers heat the finished yogurt, which kills the bacteria).  That's right, it is healthier to eat live germs than dead ones.  Here are some of the health benefits that research has shown derive directly from the live bacteria, excerpted from a summary by the Dr. Sears Health Group:
  • Yogurt is easier to digest than milk. Many people who cannot tolerate milk, either because of a protein allergy or lactose intolerance, can enjoy yogurt. The culturing process makes yogurt more digestible than milk. The live active cultures create lactase, the enzyme lactose-intolerant people lack, and another enzyme contained in some yogurts (beta-galactosidase) also helps improve lactose absorption in lactase-deficient persons. Bacterial enzymes created by the culturing process, partially digest the milk protein casein, making it easier to absorb and less allergenic.
  • Yogurt contributes to colon health.  ... yogurt contains lactobacteria, intestines-friendly bacterial cultures that foster a healthy colon, and even lower the risk of colon cancer. Lactobacteria, especially acidophilus, promotes the growth of healthy bacteria in the colon and reduces the conversion of bile into carcinogenic bile acids. The more of these intestines-friendly bacteria that are present in your colon, the lower the chance of colon diseases. Basically, the friendly bacteria in yogurt seems to deactivate harmful substances (such as nitrates and nitrites before they are converted to nitrosamines) before they can become carcinogenic...For senior citizens, who usually have more sensitive colons or whose intestines have run out of lactase, yogurt is also a valuable food. Elderly intestines showed declining levels of bifidus bacteria, which allow the growth of toxin-producing and, perhaps, cancer-causing bacteria. [my italics]
  • Yogurt improves the bioavailability of other nutrients. Culturing of yogurt increases the absorption of calcium and B-vitamins. The lactic acid in the yogurt aids in the digestion of the milk calcium, making it easier to absorb.  
  • Yogurt can boost immunity. Researchers who studied 68 people who ate two cups of live-culture yogurt daily for three months found that these persons produced higher levels of immunity boosting interferon. The bacterial cultures in yogurt have also been shown to stimulate infection-fighting white cells in the bloodstream. Some studies have shown yogurt cultures to contain a factor that has anti-tumor effects in experimental animals.
  • Yogurt is a rich source of calcium. An 8-ounce serving of most yogurts provides 450 mg. of calcium, one-half of a child's RDA and 30 to 40 percent of the adult RDA for calcium. Because the live-active cultures in yogurt increase the absorption of calcium, an 8-ounce serving of yogurt gets more calcium into the body than the same volume of milk can.  [my italics]
  • Yogurt is an excellent source of protein. ...Besides being a rich source of proteins, the culturing of the milk proteins during fermentation makes these proteins easier to digest. For this reason, the proteins in yogurt are often called "predigested." 
  • Yogurt can lower cholesterol. There are a few studies that have shown that yogurt can reduce the blood cholesterol. This may be because the live cultures in yogurt can assimilate the cholesterol or because yogurt binds bile acids, (which has also been shown to lower cholesterol), or both. 
So the lesson here is that although there are plenty of nasty microbes out there that will kill us or make us very sick, there are many that do the opposite.  In fact, as detailed in my blog "How About A Fecal Transplant?"  we apparently can't live without some of them residing in our guts.

And of course the additional lesson of yogurt is that these little critters can be very tasty, too.

Some additional info:
A summary of research studies on the benefits of yogurt from the National Yogurt Association.

WebMD's summary of yogurt benefits.


Randy Phillips said...

Thanks for the research! My wife and I love yogurt and consume it daily. Just recently we started to make our own via a friend who gave us a culture that came from Japan. There it is called "Caspian Sea" yogurt. We like it better than any yogurt commercially available. We usually have it with home-made granola and often in a "papaya boat" - half a papaya with the seeds removed, granola and topped off with home made yogurt. Can't be beat!

Christian said...

I too just started eating yogurt - love the key lime pie. I also avoid cottage cheese and I am pretty sure I won't ever come around on that stuff.

Hope all is well!

PaddleDoc said...

Good grief! My Turkish friend was 18 when he came to live with us in 1984. He spotted a small round cylinder in our reefer that said yogurt. As your research found, Turks love yogurt and might have started the whole trend. He opened it and said emphatically, "It is green!" Which I took to mean it was not commonly green in Turkey. Being of the sporting sort, he tasted it and next said, "It is sweet!" There was no question that the way he pronounced this that it was WRONG! Soon after he began making his own yogurt as he could not tolerate what we had been eating. The Good Grief, well, I've been close to vegan lately and now I might go back to yogurt given your explanation. Most of this I knew, but the benefits sound new again, so ...we'll see.

Coleen Hanna said...

I've eaten yogurt all my life, to the point where I am just sick of it. But after reading this, I think I'll go back to it. Apparently western New York is beginning to be the place for yogurt production, so there are all kinds of varieties here, especially at the local Wegman's. I'm looking for anything that is healthy and palatable at my age. The body is much more sensitive now.