A Hawaii Health Guide Reader asks: I am taking an anti-biotic medication for a bacterial infection and now I have diarrhea. I was told to take some Probiotics. What are probiotics and what are they used for? Where do I find them, or are they in some kinds of food?

Great Question! Here are the basics on Probiotics

What are probiotics?

Probiotics are small organisms that help maintain the natural balance of organisms (microflora) in the intestines also known as gut flora.

The normal human digestive tract contains about 400 types of bacteria that reduce the growth of harmful bacteria and promote a healthy digestive system.

The largest group of probiotic bacteria in the intestine is lactic acid bacteria, of which Lactobacillus acidophilus, found in yogurt and keifer is the best known. Yeast is also a probiotic substance. Probiotics are also available as dietary supplements containing potentially beneficial bacteria or yeast, with lactic acid bacteria (LAB) as the most common microbes used.

LAB have been used in the food preperation and manufacturing for many years, because they are able to convert sugars (including lactose) and other carbohydrates into lactic acid and acts as a preservative by lowering the pH and creating fewer opportunities for spoilage organisms to grow. This organism is also responsible for thecharacteristic sour taste of fermented dairy foods such as yogurt,

What are probiotics used for?

In most circumstances, people use probiotics to treat the cause of the symptoms of bloating, flatulence of undigested food and diarrhea that can be a side effect of antibiotics. Flare-ups of inflammatory bowel disease (IBD), which causes diarrhea and abdominal pain.

Probiotics are also being studied to prevent colon cancer and treat Irritable bowel syndrome.

Antibiotics kill "good" (beneficial) bacteria along with the bacteria that cause illness.

A decrease in beneficial bacteria may also lead to development of other infections, such as vaginal yeast and urinary tract infections, and symptoms such as diarrhea.

Where do I find probiotics?

Fermented Dairy foods such as keifer and yoghurt are easy sources of ingesting probiotics.

However, look closely at the lable to determine if that yogurt is effective. To offer benefit, the yogurt must contain active cultures. Most yogurt containers indicate whether active cultures are present

Taking probiotic supplements (as capsules, powder, or liquid extract) can quickly help reestabilish the colonies of the lost beneficial bacteria and thus help prevent diarrhea, but in Hawaii, be sure and check that these sources have been refrigerated, as the cultures are considered "live" and will die if exposed to heat.

Are probiotics safe?
Probiotics are considered safe because they are a naturally occuring bacteria that already are neccessary part of the normal digestive system.

Probiotic bacterial cultures are intended to assist the body's naturally occurring gut flora to reestablish themselves. They are sometimes recommended by doctors, and, more frequently, by nutritionists, after a course of antibiotics, or as part of the treatment for gut related candidiasis. Claims are made that probiotics strengthen the immune system.

The rationale for probiotics is that the body contains a miniature ecology of microbes, collectively known as the gut flora. The number of bacterial types can be thrown out of balance by a wide range of circumstances including the use of antibiotics or other drugs, excess alcohol, stress, disease, exposure to toxic substances, or even the use of antibacterial soap. In cases like these, the bacteria that work well with our bodies may decrease in number, an event which allows harmful competitors to thrive, to the detriment of our health.

Maintenance of a healthy gut flora is, however, dependent on many factors, especially the quality of food intake. Including a significant proportion of prebiotic foods in the diet has been demonstrated to support a healthy probiotic flora and may be a more effective and sustainable means of achieving the desirable health benefits promised by probiotics.

What are some of the Potential Benefits of Probiotics?

Experiments into the benefits of probiotic therapies suggest a range of potentially beneficial medicinal uses for probiotics. For many of the potential benefits, research is limited and only preliminary results are available.

Managing Lactose Intolerance:
Because LAB convert lactose into lactic acid, their ingestion may help lactose intolerant individuals tolerate more lactose than what they would have otherwise.

Prevention of Colon Cancer:
In laboratory investigations, LAB have demonstrated anti-mutagenic effects thought to be due to their ability to bind with heterocylic amines; carcinogenic substances formed in cooked meat.

Animal studies have demonstrated that LAB can protect against colon cancer in rodents, though human data is limited and conflicting.

Most human trials have found that LAB may exert anti-carcinogenic effects by decreasing the activity of an enzyme called ß-glucuronidase[5] (which can generate carcinogens in the digestive system). Lower rates of colon cancer among higher consumers of fermented dairy products have been observed in some population studies.

Cholesterol Lowering:
Animal studies have demonstrated the efficacy of a range of LAB to be able to lower serum cholesterol levels, presumably by breaking down bile in the gut, thus inhibiting its reabsorption (which enters the blood as cholesterol).Some, but not all human trials have shown that dairy foods fermented with LAB can produce modest reductions in total and LDL cholesterol levels in those with normal levels to begin with, however trials in hyperlipidemic subjects are needed.

Several small clinical trials have shown that consumption of milk fermented with various strains of LAB can result in modest reductions in blood pressure. It is thought that this is due to the ACE inhibitor like peptides produced during fermentation.

Improving Immune Function and Preventing Infections:
LAB are thought to have several presumably beneficial effects on immune function. They may protect against pathogens by means of competitive inhibition (i.e., by competing for growth) and there is evidence to suggest that they may improve immune function by increasing the number of IgA-producing plasma cells, increasing or improving phagocytosis as well as increasing the proportion of T lymphocytes and Natural Killer cells.

Clinical trials have demonstrated that probiotics may decrease the incidence of respiratory tract infections[ and dental caries in children as well as aid in the treatment of Helicobacter pylori infections (which cause peptic ulcers) in adults when used in combination with standard medical treatments.

LAB foods and supplements have been shown to be effective in the treatment and prevention of acute diarrhea; decreasing the severity and duration of rotavirus infections in children as well as antibiotic associated and travelers diarrhea in adults.

Reducing Inflammation:
LAB foods and supplements have been found to modulate inflammatory and hypersensitivity responses, an observation thought to be at least in part due to the regulation of cytokine function. Clinical studies suggest that they can prevent reoccurrences of inflammatory bowel disease in adults, as well as improve milk allergies and decrease the risk of atopic eczema in children.

Improving Mineral Absorption:
It is hypothesized that probiotic lactobacilli may help correct malabsorption of trace minerals, found particularly in those with diets high in phytate content from whole grains, nuts, and legumes

Prevents Harmful Bacterial Growth Under Stress:
In a study done to see the effects of stress on intestinal flora, rats that were fed probiotics had little occurrence of harmful bacteria latched onto their intestines compared to rats that were fed sterile water.

Irritable Bowel Syndrome and Colitis:
B. infantis 35624, sold as Align, was found to improve some symptoms of irritable bowel syndrome in women in a recent study.[ Another probiotic bacterium, Lactobacillus plantarum 299V, was also found to be effective in reducing IBS symptoms. Additionally, a probiotic formulation, VSL3, was found to be effective in treating ulcerative colitis (source: Wikipedia)

Are there other non-dairy food sources of probiotics that I can eat

Most of the probiotic research to date has focused on dairy-based products. However, many other cultures have non-dairy foods/beverages containing microorganisms that might also serve as probiotics.

Taro has long been a traditional staple food to Hawaiians and is included in the list of Canoe Plants that were taken with the voyaging Polynesians across the Pacific.

(Colocasia esculenta L.) is a root belonging to the Araceae family that originated in Asia and is now found primarily in tropical and subtropical regions. Historically it has been a major dietary staple in the islands of the Pacific, especially Hawaii, New Zealand, and Indonesia. Poi is the starchy paste of taro corm and primarily provides carbohydrates as well as other nutrients.

Poi is made by cooking, crushing, and pounding the taro corms into a paste by adding water. The amount of water determines the thickness of poi that is then strained through a cloth.

Yeast and lactic acid bacteria naturally found on the plants surface ferment the mixture eventually leading to “sour” poi (approximately 3 or more days).

Fermentation proceeds without inoculated starter cultures and usually takes approximately two to three days. The fermentation of fresh poi is similar to that occurring in the preparation of yogurt and sauerkraut.

The acid production in poi changes the pH from 6.3 to 4.5 within 24 hours and reaches its lowest pH on the fourth or fifth day of fermentation. As early as 1933, Allen and Allen11 recognized that souring was the result of acid producing bacteria such as Lactobacillus and Streptococcus. These researchers identified three Lactobacillus species and two Streptococcus (recently renamed to Lactococcus). More recently Huang et al,10 identified the predominant species in sour poi as Lactococcus lactis. Unpublished reports indicate that poi made from different varieties of taro may differ slightly in the type and amount of bacteria.

Poi is being studied as a potential probiotic by studying if poi consumption changes the microflora environment of the gastrointestinal tract. Fermented dairy products such as yogurt have been used historically for their action as probiotics—foods with live microorganisms that may benefit the host’s health by improving its intestinal microbrial balance. Probiotics have been reported beneficial for health problems including diarrhea, gastroenteritis, irritable bowel syndrome, inflammatory bowel disease (Crohn’s disease and ulcerative colitis), cancer, improved immune function, lactase digestion, hyperlipidemia, hepatic diseases, Helicobacter pylori infections, and genitourinary tract infections.

Poi might also benefit patients through use as an allergy food substitute, and as a potential nutritional supplement for weight gain in patients with weight loss problems: failure-to-thrive, cancer cachexia, and pancreatitis/cystic fibrosis.

Poi has some potential advantages compared to yogurt in therapeutic use in cancer patients. Although the role of an alkaline ash diet in the treatment of cancer is debatable, poi contributes to an alkaline diet since its calories are primarily derived from starch rather than sugar and protein. Also, poi is easily digestible due to its very small starch granule size, and poi is culturally acceptable to many people of Hawaiian or Polynesian ancestry.