Thursday, July 5, 2018

The Good, The Bad and The Ugly

The Good Gut Bacteria, the Bad Cholesterol and the Ugly Attitude About Germs
R. H. Bennett Ph.D.
Applied Life Sciences LLC

The Bad: LDL Cholesterol
Much is written about cholesterol, so it need not be belabored.  Suffice it to say some types of cholesterol are good and necessary.  One type the Low-Density Lipoprotein form of LDL is most likely not healthy when blood levels remain elevated for long periods of time.  It forms arterial plaque that is a risk factor for heart disease and more.  The drug industry has spent millions to convince us that LDL is dangerous and we must take some perilous drugs as the only means to lower the LDL.  The medical community echo’s the drug company line and pays little attention too alternative therapies.  Thus bad cholesterol inspired some bad or at least lazy medicine.
 The Ugly: Germ Attitude
Ever wonder why people of indigenous cultures have less of an issue with cholesterol. Indeed, it has a lot to do with diet.  They eat far less saturated fats and simple carbohydrates like sucrose.  They also have a very different microbiome.   How did those unique bacteria get there?  They are consumed daily in the foods and waters of their world.   If a Westerner could actually see the microbes they eat, many would be “grossed out."  Yet as Dr. Stuart Levi of Tufts University said many years ago, we don't need to be at war with the microbial world. ( 
Yet at war we are.  Take note of the myriad cleaning products that boast killing germs, 99.99% of them.  Some of these chemicals are corrosive, toxic and may actually promote antimicrobial resistance (Levy 2002). 
However, the bacteria in food and water are another matter. Our food is exceptionally low in extraneous microbes.  Given the scale of our food system, this is not a bad idea, from a public health perspective. But this broad-brush approach to control the pathogens by controlling all bacteria in food is likened to burning down the barn to kill a few mice.
  One large hamburger factory and one massive lettuce packing operation produce food for hundreds of thousands of people every day.   A few hundred pathogenic bacteria here and there in these processing plants can and has resulted in hundreds if not thousands of illnesses.
However, the economic reason that our food has so few microbes, in general, is product stability and shelf life, not food safety.
Retailers and manufacturers are always looking to extend the shelf life of products. Just a few days' more durability can translate into significant economic benefits. Shelf life depends on several factors, such as initial quality, supply chain conditions, packaging materials, and technology", writes a food scientist at Wageningen University.
One such technology for food preservation that is very effective and safe is UHT pasteurization.  It stands for Ultra High Temperature.  A notable example is UHT milk.  When you see milk, or soymilk and the like inbox on the shelf, it has undergone UHT processing.  The extremely fast heat treatment only approaches sterilization.
 Sterile is the absolute absence of life.  Something is sterile, or it is not”.
 For UTH products, as long as the package remains sealed it can reside in a warehouse or pantry for months, if not years.  Another technology that should raise eyebrows is food irradiation or Gamma irradiation.  Here the high-energy gamma radiation, very much stronger than radiation cancer therapy, does in fact sterilize.
Strawberries need to be irradiated?
Thus we can see one key to long shelf-life is to kill all the microbes including those that might be beneficial.   This aspect of food processing and its impact on the microbiome and health has fallen through the slats unnoticed.  When it becomes noticed the economics of food production will trump any serious attention to preserving beneficial microbes most foods.
The upshot of the public’s attitude about germs and the food industries zeal for profitability combines to limit if not completely remove beneficial microbes from our homes, our food, and water. 
"It may well be our food has too few beneficial microbes." 
The Good
By now readers of this Blog understand the importance of bacteria in and on our bodies.  They serve us well.  More and more people are finding ways to add beneficial bacteria back into their microbiome.  
Cultured foods and drink are popular and gaining greater use.  Probiotics command more and more shelf space and website offerings.  We read with interest about studies that suggest kids raised with pets are healthier and have fewer allergies (Nafstad 2001). 

Many companies offer probiotic and prebiotic combinations, called synbiotics, as a means to more effectively reestablish a healthy microbiome.  Several probiotic manufactures provide probiotics in microcapsules.  This encapsulation protects the bacteria such that they may reach the colon alive and more effectively than other delivery means.
Good Bugs versus Bad Cholesterol
Here is where the story takes a turn and where the Good, Bad and Ugly come together.  Researchers document that certain strains of bacteria and their enzymatic capacity to degrade and alter cholesterol.  To understand this, we need to look at cholesterol physiology a bit.
The liver synthesizes cholesterols of many types.  It also excretes them in the bile.  The Bile Duct trains the cholesterol-containing bile into the Small Intestine. Some of this cholesterol is reabsorbed back into the blood, and some is excreted in the feces after being changed in form by the GOOD bacteria
Some people are very efficient in reabsorbing cholesterol.  Others due to the microbes and the diet are better at excreting cholesterol.  Some types of dietary soluble fiber, such as those found in oats will bind cholesterol and facilitate its excretion (Behall 1007).  Beta Glucans from oat
bind LDL cholesterol and prevent its reabsorption.   Many foods contain Beta Glucans, but it is not clear if these will be as effective as the oat glucan.
Certain bacteria in the small intestine have a positive documented role in reducing reabsorption of LDL Cholesterol. Remarkably, the good HDL is unaffected.    Strains of Lactobacillus and Bifidobacterium reveal in clinical trials to significantly reduce serum HDL in subjects with high blood HDL (Xiao 2003, Rerksuppaphol 2015).  Even the medically conservative American Heart Association reports the benefits of probiotics on serum cholesterol.  In this study HDL, Cholesterol decreased by almost 12% but had no effect on the good cholesterol (Am Heart Assn. 2012).
The Good in the Small Intestine.
Almost all of the science on the microbiome focuses on the large intestine or colon.  It is where the trillions of bacteria reside and operate.  Bile secretion and cholesterol reabsorption occurs in the small intestine.   It is there the probiotics have their cholesterol-lowering effect.   Many companies target the colon with unique delivery systems like microencapsulation.  These systems may not improve small intestine delivery at all.   Thus products that have the potential to act on cholesterol in the small intestine will be those that deliver billions of organisms directly into the stomach and hence the small intestine.  Since these microbes do not thrive in the small intestine, they need to be consumed daily.  In folks with very high cholesterol, they may need to take the dose twice a day to get the maximum benefit.

Another possible delivery of probiotics to the small intestine may be homemade yogurts and kefir.   Commercial probiotic strains shown to metabolize cholesterol can readily be grown in yogurt incubators and the like.   The use of UTH milk or soymilk is recommended, as it will have little or no bacteria in it that may confound or interfere with the desired cultures.  To select a product to take or, use as seed cultures the following table may be useful.  Clinical studies suggest a probiotic dose of at least one billion CFU or organisms.  This dose is achievable in many products or in home prepared cultures.

Which Species Metabolize Bile  (Kumor 2012)

HATS Probiotics:  Human Adapted, Targeted, Symbiotic

The ability of a probiotic to break down or hydrolyze bile is a feature of HATS microbes.   Thus any HATS probiotic take at large doses at least once or twice per day has good potential to reduce HDL cholesterol.
 Given the somewhat dangerous side effects of the Statin drugs prescribed for high cholesterol; this is good news in a bad and ugly game.


American Heart Association. (2012, November 5). Daily doses of a new probiotic reduces 'bad' and total cholesterol. ScienceDaily. Retrieved July 1, 2018 from

Behall, Kay M., Daniel J. Scholfield, and Judith Hallfrisch. "Effect of beta-glucan level in oat fiber extracts on blood lipids in men and women." Journal of the American College of Nutrition 16.1 (1997): 46-51.

Levy, Stuart B. "Factors impacting on the problem of antibiotic resistance." Journal of Antimicrobial Chemotherapy 49.1 (2002): 25-30.
Kumar, Manoj, et al. "Cholesterol-lowering probiotics as potential biotherapeutics for metabolic diseases." Experimental diabetes research 2012 (2012).

Nafstad, P., et al. "Exposure to pets and atopyrelated diseases in the first 4 years of life." Allergy 56.4 (2001): 307-312.

Rerksuppaphol, Sanguansak, and Lakkana Rerksuppaphol. "A randomized double-blind controlled trial of Lactobacillus acidophilus plus Bifidobacterium bifidum versus placebo in patients with hypercholesterolemia." Journal of clinical and diagnostic research: JCDR 9.3 (2015): KC01.

Xiao, J. Z., et al. "Effects of milk products fermented by Bifidobacterium longum on blood lipids in rats and healthy adult male volunteers." Journal of dairy science 86.7 (2003): 2452-2461.


  1. Excellent information Dr. Bennett , I really enjoy your blog !!!!

  2. Thanks Michael. Glad to know its valuable