A: Some kinds of bacteria do cause illnesses and disease in humans. However, the majority of bacteria do not cause disease. In fact, there are types of bacteria that are actually beneficial. "Good" bacteria, known as probiotic bacteria, are used in the manufacturing of food beverages. Some examples of foods that have probiotic food ingredients are buttermilk, yogurt, cheese, sausage, and acidophilus milk.

These same kinds of probiotic bacteria are present in our intestines and help to keep the digestive system running by digesting food and processing waste.

A: Probiotics are live bacteria that are non-toxic and do not cause disease (non-pathogenic).¹

Some of the best-understood probiotic bacteria include members of the Lactobacillus and Bifidobacterium groups. Because of the Lactobacillus and Bifidobacterium's ability to break down lactose, these probiotic bacteria are also known as lactic acid bacteria. Both of these types of probiotic bacteria are well studied and are available in both food and dietary supplements.¹

A: Actually, the bacteria that is in yogurt, our intestine, and most natural supplements are the same types of probiotic bacteria, Lactobacillus acidophilus and Bifidobacteria longum. Because of this, these bacteria are referred in a generic sense as probiotics. So, the term probiotics may refer to the "good" bacteria that are present in food, or that live in our intestine, or that are part of a natural supplement.

A: Normal microflora (the term commonly used for intestinal bacteria) is associated with good health. An imbalance in this natural microflora (when the beneficial probiotics are outnumbered by the harmful bacteria) is frequently associated with various disease states such as yeast infections and colon cancer.²

Eating foods or taking a nutritional supplement containing probiotic bacteria can help support and modify the composition of the large intestine microflora.³ Microflora of the large intestine assist digesting through fermentation (by making the intestines more inhospitable to invading bacteria species), protection against disease-causing bacteria, and stimulation of the immune system.² The probiotics, Lactobacillus and Bifidobacteria, occupy a central role in the intestinal flora and provide health benefits.

A: Lactose is an important sugar that is converted to lactic acid by lactic acid bacteria. Lactose intolerance results from an inability to digest lactose, due to the failure of small intestine mucosal cells to produce lactase, an enzyme needed to digest lactose.⁴ This often results because of genetics, gastrointestinal disease, or because of the decline in the amount of intestinal lactase levels associated with aging.⁵ Lactase deficient people accumulate non-absorbed lactose in the gastrointestinal tract, which draws water and electrolytes into the gut and speeds waste through the intestines, leading to bloating, cramping, and diarrhea.^5,6

Approximately 50 million people in the United States have partial to complete lactose intolerance.

Lactic acid bacteria have been shown to help the breakdown of lactose, specifically by enhancing the activity of lactase (beta galactosidase), which improves lactose digestion and tolerance.^6,7 Furthermore, in a randomized, controlled clinical trial, Bifidobacteria longum was shown to assist in the breakdown of lactose and relieve the symptoms of lactose intolerance (flatulence) in people with lactose intolerance.⁸

A: Digestive enzymes, such as protease, amylase, and lipase, act upon food, breaking it down into simpler components that can be used by the body for energy.⁹ Without enzymes, digestion could not take place. Therefore, the food that we eat could not be absorbed and utilized by our bodies.

Probiotics help the enzymes to digest food and process waste. In essence, probiotic bacteria and enzymes work together to ensure that the digestive tract is running smoothly. When taken together, enzymes assure greater levels of digestion and absorption of your food, and probiotic bacteria aid the enzymes in digestion and keep problems in check.

A: Absolutely not! Probiotic bacteria, such as lactobacillus acidophilus, have been found to help prevent vaginal yeast infections in women that suffer from these reoccurring infections.¹⁰

Approximately 35% of vaginal infections are caused by the yeast, Candida albicans. Candida is a fungus that is a component of the normal gastrointestinal microflora.¹¹ However, Candida must not be allowed to increase in numbers. An overgrowth is associated with adverse health effects like vaginal infections, oral thrush, or even serious systemic yeast infections. Probiotics have been shown to keep levels of Candida in check.¹¹

Probiotic bacteria have also been demonstrated to have anti-cancer properties. In a clinical study, colon cancer patients given Lactobacillus acidophilus fermented milk showed a significant increase in numbers of intestinal Lactobacilli and a decrease in risk factors associated with colon cancer.

Patients suffering from inflammatory bowel diseases, such as ulcerative colitis and Crohn's disease, can benefit from probiotic bacteria supplementation. Studies have shown that probiotic bacteria assist in maintaining remission in ulcerative colitis and preventing reoccurrence of Crohn's disease. Manipulating the intestinal flora may prove to be more effective and better tolerated than the durgs that are conventionally give to treat these diseases.^12-16 In one study, Lactobacillus acidophilus was found to improve the intestinal barrier and clinical status in children suffering from Crohn's disease.¹²

Probiotics supplementation can also improve and prevent skin diseases, such as eczema. Studies have shown that probiotic bacteria can actually control inflammation associated with skin conditions.^17-19 In one study, infants with eczema who were given probiotic-supplemented formulas showed a significant improvement in skin condition.¹⁹

A: Probiotic bacteria do not permanently colonize in the body. They need to be replenished by the consumption of foods containing probiotic bacteria or by taking a probiotic natural supplement. Whatever form you choose to replenish the intestinal probiotics, they need to be ingested daily for their health-promoting effects to continue.