Lactobacillus acidophilus - The Popular Probiotic With Many Health Benefits

Lactobacillus acidophilus is probably the first name that people think of when they are asked to name a popular probiotic. L acidophilus has such widespread name recognition because it is know to have health benefits, even if people don't know what those benefits are. Read on and you'll be ahead of the crowd.

Why Lactobacillus acidophilus ?

Lactobacillus acidophilus means rod-shaped, lactic-acid producing bacteria that grow well in an acidic environment. It is one of the bacteria that give foods and drinks such as yogurt the tangy taste.

Yogurt can contain Lactobacillus acidophilus

It is also the bacterium in acidophilus milk that digests the lactose in the milk, making it easier for lactose-intolerant people to consume. Nowadays, acidophilus milk is not easy to find in stores. It has been replaced by lactose-free milk to which the lactose-degrading enzyme, lactase, extracted primarily from yeasts, has been added. There are no live bacteria used.

The lactose-digesting capabilites of L. acidophilus depend on the numbers of live bacteria and the conditions they live in, so taking extra Lactobacillus acidophilus does not necessarily mean that you’ll be able to digest lactose. Most of the time L. acidophilus reduce some of the lactose in the product they are manufactured in, but they can’t reduce any more than that with the small numbers of microbes in the product.

However, Lactobacillus acidophilus can utilize, at least in small amounts, many different sugars, from easily digested ones to sugars that humans cannot digest, so having it in your body is beneficial to you.

In the human body, Lactobacillus acidophilusis found throughout the gastrointestinal tract and in the female vagina and urinary tract. As a species, it has strong adhesion properties to intestinal tissue and mucus cells. In 1900, Dr. Ernst Moro (1874-1951) presented the first characterization of Lactobacillus acidophilus bacteria from infants, so the benefits of L. acidophilus have been known for a long time.

What Else Does L. acidophilus Do?

As a genus, Lactobacillus acidophilus are homofermentative, meaning that they produce one end product from glucose; their end-product is lactic acid. Lactic is considered to be a weak acid, but it is stronger than acetic acid (the short-chain fatty acid used in vinegar), all conditions being equal.

Lactic acid produced by Lactobacillus acidophilus lowers the pH in the body parts where it lives, making the living conditions too acidic for many pathogenic microbes. The lower pH also aids in mineral absorption from food. L. acidophilus also secretes chemicals that assist in intestinal electrolyte absorption.

Some scientists blame the acidity from L. acidophilus for contributing to dental caries because acid can dissolve enamel. However, the lactic acid produced from L. acidophilus is nothing compared to the acids from carbonic acid, phosphoric acid, and citric acid in carbonated drinks like Coca Cola, Pepsi, Mountain Dew, etc. that can give the drink a low pH of 2.5 (very acidic).

Tooth decay is a sign of overall health, not just acid etching

Additionally, the environment of the mouth is more complicated than some marketers would have you believe, so cavities are a sign of an imbalance of many factors in the body, not just the presence of L. acidophilus. However, if you let any acid sit long enough on enamel, eventually the acid will react with it, so you’ll still need to brush and floss your teeth.

Whether or not you need fluoride in your toothpaste is beyond the purpose of this site, but you can visit the Fluoride Action Network at http://www.fluoridealert.org .

Other Health Benefits

The family tree of L. acidophilus has had revisions over the years. Microbes that were considered to be “L. acidophilus” were found to be species of acidophilus, amylovarus, crispatus, galllinarum, gasseri and johnsonii. In March of 2020 the Lactobacillus genus was rigorously re-evaluated, and while many probiotics previously classified as Lactobacillus are now in other genera, acidophilus is one that remained in the genus.

There are numerous strains of L. acidophilus on the market, but some of them are more common than others. L. acidophilus 4356 is the type strain for the species which retained the acidophilus name in scientific analyses, but that may not mean that any product you buy that simply says, “L. acidophilus” is necessarily the 4356 strain. There’s no way to know without contacting the manufacturer.

Some of the results from studies on L. acidophilus show the importance of ingesting probiotics as part of your daily life as prevention, rather than trying to use them as drugs to treat infections and diseases. In general,L. acidophilus have:

  • The ability to produce lactic acid to lower the pH to make conditions inhospitable for many pathogenic microbes
  • The ability to produce bacteriocins
  • The ability to produce lactic acid to aid in mineral absorption from food
  • The ability to secrete special compounds to improve electrolyte absorption in the small intestine
  • The ability to reduce fecal enzymes that if left alone can change relatively harmless compounds into potentially harmful ones
  • The ability to ferment many different sugars, from easily digested ones to sugars that humans cannot digest
  • The ability to maintain the integrity of your intestines by interacting with your intestinal cells to prevent leaky gut
  • The ability to prevent the invasion and adhesion (ability to stick) of pathogenic microbes. An example of this is an S-layer protein in L. acidophilus CICC 6074 that shows the ability to prevent enteropathogenic Escherichia coli  from adhering to human cells in vitro by competitively excluding it.
  • The ability to help with blood glucose control and weight loss, as in this study on rats using L. plantarum and L. acidophilus.

L. acidophilus Strain Information

Sometimes specific strains of microbes are trademarked by food product and supplement manufacturing companies, and they become more popular due to the advertising and availability of the strains.

This sampling of strains of  Lactobacillus acidophilus have enough scientific publications about them to make them noteworthy (some of that research is funded by companies that use the bacteria in their products):

L. acidophilus DDS-1

L. acidophilusEr 317/402

L. acidophilus NCFM

L. acidophilus NAS

Go back to the Lactobacillus page.


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