Inside each of us live vast numbers of bacteria without which we could not remain in good health. Before looking at the amazing things they do, reflect on just how many of them we house.

There are several thousand billion in each person (more than all the cells in the body) divided into four hundred species, most of them living in the digestive tract. If they were all placed together the total weight of this "friendly" bacteria would come to nearly four pounds and, in fact, about a third of the fecal matter (water removed) which you pass consists of dead or viable bacteria.

The Role of Friendly Bacteria in Health.

These bacteria are not parasites. They do not just take up residence and do nothing in return, but perform many important functions in the body. We live in true symbiosis with them. As long as we provide them with a reasonable diet and as long as they remain in good health, these bacteria provide excellent service in return.

However, not all of the friendly bacteria perform the same functions, some being far more useful and plentiful than others. These are the ones presented here. Certain bacteria help to maintain good health while others have a definite value in helping us regain health once it has been upset.

These dual protective and therapeutic roles help explain why the word "probiotics" was coined since it means "for life" :

• They manufacture some of the B Vitamins including niacin (B3), pyridoxine (B6), folic acid, and biotin.
• They manufacture the milk-digesting enzyme lactase which helps digest dairy products
• They actively produce antibacterial substances which kill or deactivate hostile disease-causing bacteria. They do this by changing the local levels of acidity, by depriving pathogenic (disease-causing) bacteria of their nutrients, or by actually producing their own antibiotic substances which can kill invading bacteria, viruses, and yeasts. Naturally enough they are doing this to preserve "their" territory.
• Some bacteria (such as bifidobacteria and acidophilus) have been shown to have powerful anticarcinogenic features which are active against certain tumors.
• They improve the efficiency of the digestive tract - when they are weakened, bowel function is poor.
• The effectively help to reduce high cholesterol levels
• They play an important part of the development of a baby's digestive function and immune system. Bifidobacteria infantis is aquired from breast milk. When it is in poor supply allergies and malabsorption problems are more common.
• They help protect against radiation damage and deactivate many toxic pollutants.
• They help to recycle estrogen (a female hormone) which reduces the likelihood of menopausal symptoms and osteoporosis
• Therapeutically they have been shown to be useful in the treatment of acne, psoriasis, eczema, allergies, migraine, gout (by reducing uric acid levels), rheumatic and arthritic conditions, cystitis, candidiasis, colitis, irritable bowel syndrome, and some forms of cancer.

Types of Friendly Bacteria

Of the friendly bacteria which help the human body most are the residents, while the others are transient visitors, staying in your digestive tract for a few weeks before passing on. The principle forms of friendly bacteria are :

Lactobacillus Acidophilus

This is the main inhabitant of the small intestine in humans and animals. It is also found in the mouth and vagina. Acidophilus manufactures lactase to digest milk sugar and produces lactic acid which suppresses undesirable bacteria and yeasts. Some strains produce natural antibiotics. They also lower cholesterol levels and kill candida yeasts, and are very susceptible to poor diet and stress conditions, pollution, and antibiotics such as penicillin.

Lactobacillus Bulgaricus

This is a transient but very important bacteria. Together with Streptococcus thermophilus it makes yogurt. Some strains of bulgaricus and thermophilus also produce antibiotics which kill harmful bacteria. By manufacturing lactic acid these bacteria encourage a good environment for the resident bacteria such as acidophilus and the bifidobacteria.

Bifidobacterium Bifidum and Bifidobacteriumlongum

These are the main inhabitants of the large intestine. Bifidobacterium Bifidum is also found in the vagina and the lower part of the small intestine. In breastfed infants and adolescents these make up 99% of the entire flora of the bowel. There is strong evidence that the numbers and efficient working of these bacteria decline as a person ages and with any decline in our health status.

The bacteria produce a number of specialized acids and use these to prevent colonization of the large intestine by invading bacteria, yeasts and some viruses. They also prevent potential toxicity from nitrites in food and manufacture B Vitamins as well as helping detoxify bile from which they recycle estrogen in women.

Bifidobacteria Infantis

This is the main inhabitant of every infant's intestines and is found in small amounts in the vagina. It's functions are very much the same as the other bifidobacteria. In a freeze-dried form it is the only probiotic product which should be supplemented to infants without professional guidance.

What Damages the Friendly Bacteria ?

Many factors influence just how healthy the flora are. While the type of friendly bacteria living in a region may seem much the same in health and disease, the tasks they perform change according to circumstances. For example, when bifidobacteria are in a good state of health they will detoxify pollutants and carcinogens as well as manufacture various B Vitamins. When in a poor state of health, however, they just cannot do these jobs as well or at all.

What Makes Friendly Bacteria Function Less Efficiently ?

The level of local acidity is one major influence upon the function of the friendly bacteria and this is contributed to by diet, digestive function, and stress. Another important influence is the speed of peristalsis (the wavelike contraction of the intestines) which moves food along the digestive tract. If it is too rapid (as in diarrhea, irritable bowel syndrome, or colitis) this severely reduces the efficiency of the flora. If it is too slow (as in atonic or spastic constipation) this too causes changes in their function.

The type of diet you eat is a major influence on bacterial health. The bacteria are healthier on a diet rich in complex carbohydrates (vegetables, whole grains, legumes) and low in animal fats, fatty meat, sugars, and cultured dairy products (especially "live" yogurt and cottage cheese). Not surprisingly, the diet which is best for people is also ideal for healthy bacteria.

They are also influenced to a major extent by the degree of infection by yeasts and bacteria to which the bowel is subjected. Certain drugs, especially antibiotics, can severely upset this delicate balance (penicillin will kill friendly bacteria just as efficiently as it will kill disease-causing bacteria). Steroids (hormonal drugs such as cortisone, ACTH, prednisone, and birth control pills) also cause great damage to the bowel flora.

Damaged friendly bacteria can regain health and efficiency by dealing with any of the factors listed above, especially diet and stress reduction, and by supplementing good quality freeze-dried bacteria such as Lactobacillus Acidophilus or Lactobacillus Bulgaricus. The way the products are made is important :

• When being seperated from the "soup" in which they are cultured, some manufacturers spin the bacteria in a centrifuge. This damages the delicate chains of bacteria, which does not happen when a slower (and therefore more expensive) filtration process is used. This information should be on the container.
• It is preferable to take the friendly bacteria as a powder, as similar damage can occur if the bacteria are in a capsule or tablet form. The bacteria should be stored in a dark glass (never plastic) container.
• Viable cultures of the particular bacteria you want, which are capable of recolonizing the intestines, as a rule need to be refrigerated after the opening of their container. They should not be taken at meal times to avoid the extreme acidity of the stomach when it has food in it.
• All good products should carry a guarantee of viable colonizing bacteria up to a specific expiration date.

When to Use Probiotic Supplements

Probiotics may be used in the following cases :

• Under professional guidance if there are chronic bowel problems or ongoing infections such as candidiasis.
• As a preventive against food poisoning when travelling (bifidobacteria and acidophilus kill most food poisoning bacteria)
• By all premenopausal and menopausal women to reduce chances of osteoporosis
• By anyone with high cholesterol problems
• By anyone with chronic health problems (acne, skin problems, allergies, arthritis, cancer, ect...) under professional guidance
• By anyone receiving radiation treatment
• By anyone having reccurent vaginal or bladder infections (thrush or cystitis)
• Bifidobacteria Infantis should be given to all babies.

Which Bacteria Can the Friendly Flora Control ?

• In nineteen cases of non-specific infection of the vagina treated with acidophilus (doderlein bacillus strain) 95% were cured.
• In twenty five cases of Monilia vaginitis 88% were cured and 12% relieved of symptoms. In 444 cases of trychomas vaginitis 92% were cured and remained infection free up to a year later.
• The cidophilin antibiotic which Lactobacillus acidophilus produces will kill 50% of twenty seven different disease causing bacteria.
• Sixteen children with salmonella poisoning and fifteen with shigella infections were cleared of all symptoms using acidophilus. Bifidobacterium Bifidum effectively kills or controls E. coli. Straphylococcus Aureus (cause of toxic shock syndrome), and shigella. Acidophilus can also control viruses such as herpes.

Breast Milk and the Health of Intestinal Flora

German research shows that the state of the intestinal flora in most breastfed babies today is similar to that of formula fed babies forty years ago. The result is malabsorption and food sensitivity problems as well as increase in allergies and susceptibility to infection. Further research has pointed to contamination of breast milk with pollutants such as DDT and dioxin. This suggests that supplementation of all babies with Bifidobacteria Infantis may be a helpful strategy.