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Lactic acid bacteria

Lactic acid bacteriaLactic acid bacteria are many different types of bacteria that produce lactic acid by fermenting carbohydrate. They are widespread in the kingdom of plants and animals. Lactic acid bacteria are also called probiotics which means "pro life" and constitute a vital part of our enormous intestinal microflora that contains more bacteria than body cells and weighs around two kilos.

Lactic acid bacteria also constitute an important part of the vaginal microflora. At birth, lactic acid bacteria and other vital micro organisms are transferred to the baby via the birth canal and via breast milk. The baby's microflora is considered to be fully developed around the age of three years.

Each human has its own unique microflora, and the many different species thrive in a delicate balance known as symbiosis. Certain intestinal bacteria and fungi may harm the digestion and turn into pathogens if they become too dominant, spread, and reach numbers that the beneficial lactic acid bacteria are unable to keep under control.

There are three main groups of beneficial bacteria: Acidophilus, Lactobacillus, and Bifidus

Functions and importance for

  • Healthy intestinal flora and good digestion
  • Production of lactic acid that lowers the pH value (acid environment)
  • Inhibition of growth of pathogen bacteria by producing anti-bacterial compounds
  • Displacement of harmful bacteria and fungi from the binding sites of the intestinal mucosa
  • Immune defence. A healthy microflora benefits the immune defence by influencing lymphoid cells in the intestinal wall, and these are important for the production of antibodies. The microflora may also help regulate intestinal permeability.
  • May counteract allergies and inflammatory diseases
  • May lower the risk of overweight

Deficiencies and poor utilisation may be caused by

  • Antibiotics
  • Refined diets
  • Lack of dietary fibre
  • Caesarean section
  • No breastfeeding

Deficiency symptoms

  • Poor digestion
  • Constipation
  • Diarrhea
  • Irritable colon
  • Vaginal symptoms including odor, stinging, itching, and discharge
  • Possibly overweight
  • Other complications caused by poor digestion

Intestinal flora and disease

A lot of research looks at the intestinal flora and its importance to our health and the risk of developing an array of diseases. Constipation compromises the immune defence because toxic waste compounds stay too long in our intestines. Irritable colon is considered a concealed type of constipation and must be treated as such. Studies suggest that many individuals with imbalances in their microflora have a more penetrable intestinal mucosa ("leaky gut") than normally. This means that undesirable substances can pass through more easily and enter the bloodstream. There is also evidence that diseases such as allergies, intolerance, chronic fatigue syndrome, fibromyalgia, and autism may originate from the intestines.
The intestinal microflora is different in those who are overweight or suffer from inflammatory bowel diseases.


Fermented dairy and soy products, sourdough, sauerkraut (pickled cabbage) and other fermented products - plus supplements containing lactic acid bacteria.

Milk and sour milk products

Lactic acid bacteria do not contain milk but they convert lactose (lactose) to lactic acid by means of fermentation. Modern sour milk products generally only contain a limited amount of the beneficial bacteria, simply because the fermentation is stopped sooner than in old days. Also, sour milk products often contain a lot of sugar that inhibits or destroys the lactic acid bacteria.

Increased need

  • Poor digestion
  • The above listed deficiency diseases
  • Prevention of traveler's diarrhea
  • Children who are born with caesarean section
  • Children who are not breastfed


Most supplements contain different strains of Lactobacillus species that mainly colonise the small intestine and Bifido strains that represent the major part of the microflora in the colon. Lactobacillus reuteri protectis is present throughout the entire gastro-intestinal tract and therefore has a much wider scope of action.

Special supplements are available for the digestion and for babies and infants, just like there are suppositories and capsules for vaginal insertion.


Like most other types of bacteria, lactic acid bacteria are sensitive to antibiotics. Antibiotic treatments do not only wipe out the harmful bacteria but also the beneficial lactic acid bacteria and the natural microflora.

It is therefore recommended as a preventative measure to take supplements with lactic acid bacteria three hours before or after taking antibiotics. It may even be a good idea to continue doing so for 1-2 weeks after the antibiotic treatment has been terminated, or at least until the microflora has been reestablished.

Farmers know that animals who get antibiotics (growth promoters) in their feed grow five to fifteen times in size. Human studies reveal that children who are treated with antibiotics during the first six-month period of their lives are at increased risk for overweight compared with children who are not given antibiotics.

Overdosing - side effects

No side effects have been reported with use of approved supplements. In rare cases, allergy towards lactic acid bacteria or one or several of the tablet excipients may occur.